BACKGROUND Plasma cell myeloma is a neoplastic plasma cell disorder that usually presents after the fifth decade of life; it is rarely described in younger population especially under 30 years of age. However, there are conflicting reports in the literature about the clinical behavior and overall survival in younger age groups. In approximately 2% of plasma cell myeloma, the morphology of the neoplastic cells is highly pleomorphic, quite anaplastic, and may resemble metastatic tumor cells. While this poses a challenge for morphological interpretation during diagnosis, it has been demonstrated that bone marrow morphologic features (including diffuse sheet growth pattern, immature cell morphology and high mitotic index) significantly correlates with high risk disease. Moreover, there is limited description available about the morphology of the neoplastic cells when correlating the age at presentation with the clinical outcome/biological behavior; hence, the need to report and collect such cases. CASE REPORT We report a case of plasma cell myeloma in a 22-year-old male who presented with non-specific clinical features and posed a diagnostic challenge during clinical, radiological, and laboratory examination. The pathology specimens showed anaplastic morphology. Unfortunately, after diagnosis, despite treatment with brotezomib, his disease had an aggressive clinical course and he passed away 4 months after diagnosis. CONCLUSIONS Although plasma cell myeloma is rare in patients younger than 30 years, it must be considered in the differential diagnosis and investigated properly especially in patients with clinical suspicion of a metastatic non-hematological tumor. The anaplastic variant in a young patient is a diagnostic challenge and is associated with bizarre morphology, aggressive presentation, adverse cytogenetics, resistance to chemotherapy, and poor, short-term, survival.

Multiple myeloma is a neoplasm of plasma cells characterised by the presence of M protein in serum and urine. Angiogenesis and proliferation play a major role in the pathogenesis of various neoplasms. The study evaluated proliferation and angiogenesis in 48 cases of myeloma, and correlated it with morphological and clinical parameters. The histomorphological features like plasma cell morphology, percentage of plasma cells and pattern of infiltration were studied in the bone marrow aspirate and trephine biopsy. Angiogenesis was assessed by calculating the microvessel density (MVD) using immunohistochemistry for CD34. Proliferation was assessed using Ki67 and CD38 highlighted the plasma cells. The mean Ki67 % was found to be significantly higher (19.6 % range 2-40 %) in poorly differentiated morphology compared to well differentiated morphology (4.06 % range 0.2-20 %) (p = 0.003). The mean MVD in the well differentiated morphology was 10.6 (range 1.2-47.4) compared to 20.3 (range 6.9-39.6) in the poorly differentiated morphology (p = 0.04). The mean MVD was 5.7 (range 1.2-12.8) in the interstitial pattern of infiltration compared to 20.04 (2.9-47.4) in the diffuse pattern (p < 0.0001). The mean MVD was 6.4 in cases with serum albumin >3.5 gm/dl compared to 13.3 in cases with serum albumin <3.5 gm/dl (p = 0.009). Both the Ki67 and MVD showed an increasing trend with the clinical staging. Thus the study of proliferation and angiogenesis in bone marrow biopsy is useful for prognosticating patients with multiple myeloma.

Over 100 broadly neutralizing antibodies have been isolated from a minority of HIV infected patients, but the steps leading to the selection of plasma cells producing such antibodies remain incompletely understood, hampering the development of vaccines able to elicit them. Rhesus macaques have become a preferred animal model system used to study SIV/HIV, for the characterization and development of novel therapeutics and vaccines as well as to understand pathogenesis. However, most of our knowledge about the dynamics of antibody responses is limited to the analysis of serum antibodies or monoclonal antibodies generated from memory B cells. In a vaccine setting, relatively little is known about the early cellular responses that elicit long-lived plasma cells and memory B cells and the tools to dissect plasmablast responses are not available in macaques. In the current study, we show that the majority (>80%) of the vaccine-induced plasmablast response are antigen-specific by functional ELISPOT assays. While plasmablasts are easily defined and isolated in humans, those same phenotypic markers have not been useful for identifying macaque plasmablasts. Here we describe an approach that allows for the isolation and single cell sorting of vaccine-induced plasmablasts. Finally, we show that isolated plasmablasts can be used to efficiently recover antigen-specific monoclonal antibodies through single cell expression cloning. This will allow detailed studies of the early plasmablast responses in rhesus macaques, enabling the characterization of both their repertoire breadth as well as the epitope specificity and functional qualities of the antibodies they produce, not only in the context of SIV/HIV vaccines but for many other pathogens/vaccines as well.

Tumor-lysis syndrome is a rare complication in patients with multiple myeloma. However, bortezomib treatment for myeloma is often associated with tumor-lysis syndrome.

We developed an index called the rapid anemia progression index, which represents the duration and progression of anemia, to evaluate risk factors for tumor-lysis syndrome. We retrospectively reviewed 35 relapsed or refractory myeloma patients treated with bortezomib-containing treatment in our institution. We analyzed various parameters, including albumin, lactase dehydrogenase, β2-microglobulin and creatinine, similar to the rapid anemia progression index, and evaluated the risk factors for tumor-lysis syndrome associated with bortezomib by the Cairo-Bishop definition.

Clinical tumor-lysis syndrome occurred in six patients (17.1%). Tumor-lysis syndrome occurred during the first course of bortezomib-containing treatment among all the patients. The result of the area under the receiver operating characteristic curve for the rapid anemia progression index was 0.759 (P = 0.049). The rapid anemia progression index was more accurate than the index of lactate dehydrogenase, β2-microglobulin, albumin and creatinine according to the receiver operating characteristic curve. For a cut-off point of -1.12 for the rapid anemia progression index, the sensitivity and specificity were 66.7 and 82.8%, respectively.

The rapid anemia progression index is related to clinical tumor-lysis syndrome associated with bortezomib treatment for multiple myeloma patients with a cut-off point of -1.12 g/dl/month.

Soluble interleukin-6 receptor (sIL-6R) is part of IL-6 receptor that may stimulate cells that do not express the whole molecule. It may enhance myeloma cell proliferation and furthermore angiogenesis. The aim of the study was to evaluate the clinical significance and the relationship between serum levels of sIL-6R, with various stimulators of angiogenesis, such as hepatocyte growth factor (HGF) and interleukin-18 (IL-18) and with markers of proliferation, such as beta-2 microglobulin (B2M) levels and plasma cell Ki-67 proliferation index in the bone marrow, in patients with multiple myeloma (MM). We studied 45 newly diagnosed MM patients. Serum levels of sIL-6R, HGF, IL-18, and B2M and Ki-67 proliferation index (Ki-67 PI) in bone marrow's plasma cells were determined. The mean concentrations of sIL-6R, HGF, IL-18, and B2M and the value of Ki-67 were significantly higher in the patients compared to controls and with increasing disease stage. sIL-6R was strongly positively correlated with HGF, IL-18, B2M, and Ki-67 PI. There is a positive correlation between plasma cell growth, as determined by Ki-67 PI, and different angiogenic cytokines, such as HGF and IL-18, with sIL-6R. This relationship suggests the significant role of these cytokines in the proliferation and disease activity in MM patients.

Histological diagnosis of burn depth lacks consensus. The purpose of this study was to determine whether Ki-67, a cell proliferation marker, provides an index of integument viability after burn injury. Induction of thermal burn injuries (3, 12, 20, 30, 75, 90, and 120 seconds) were made with a brass rod heated to 100°C on the dorsal trunk of the swine. Controls were created with a brass rod heated to 37.5°C. Four 6-mm biopsies were obtained from each site for histological analysis of Ki-67. Biopsies were taken at the following times postinjury: 1, 12, 24, 36, 48, 72, and 96 hours. The results illustrate a characteristic Ki-67 nuclear staining in the basal layer of the epidermis and in the hair follicle. With increasing thermal injury, the nuclei of the cells changed morphology: condensing, fragmenting, and elongating. The uniqueness of the labeling index was to include only morphologically intact nuclei as having capacity to proliferation. Quantitative analysis showed a reduction in the mean number of Ki-67-positive cells, suggesting a reduced regenerative capacity. This study supports using this index as a means of performing histology for burn depth analysis. In future studies, determining viability of partial-thickness burns will require multiple histological markers such as Ki-67 in addition to hematoxylin and eosin staining.

A proliferation-inducing ligand (APRIL) promotes survival and drug resistance in multiple myeloma (MM) cell lines. We studied the effect of APRIL on cell-cycle behavior in primary MM cells and correlated our findings with D-type cyclin expression by immunohistochemistry and/or Western blotting. In MM cases, expressing cyclin D2 APRIL significantly increased the percentage of CD138(+) cells in S + G(2)/M phase (from 8.4% ± 1.9% to 14.3% ± 2.6%, n = 15, P < .01), whereas a lesser effect was seen in cases expressing cyclin D1 (n = 18). Cell-cycle response to APRIL was most marked for cyclin D2-expressing cases with IgH translocations (P < .01) and was accompanied by increased expression of cyclin D2, CDK4, CDK6, and phospho-retinoblastoma protein. Cell-cycle proteins in cyclin D1(+) cells were not modulated by APRIL. Surface expression of B-cell maturation antigen and transmembrane activator and calcium-modulating cyclophilin ligand interactor was not significantly different between cyclin D1(+) and D2(+) MM cells. We observed activation of nuclear factor-κB and PI3-kinase pathways in response to APRIL in both cyclin D1(+) and D2(+) MM cells. In conclusion, APRIL stimulates G(1)/S progression in cyclin D2(+) MM cells bearing IgH translocations but has minimal effect on cyclin D1(+) cells, suggesting MM cells from different cyclin D/translocation classes rely on different mechanisms for cell-cycle re-entry.

Patient tailored therapy will serve the fundamentals of future cancer treatment. For this it will be imperative to characterize the tumor and to acquire precise predictive and prognostic information. We can achieve this by using not only monogenic (like ER, PR, HER-2, Ki-67) but also multigene assays, which can provide answers to several diagnostic questions simultaneously. We present a summary of currently available RT-PCR and microarray based multigene tests including MammaPrint, Oncotype DX, BLN Assay, Theros Breast Cancer Index SM, MapQuant DX, ARUP Breast Bioclassifier, Celera Metastatic Score, eXagen BCtm, Invasive Gene Signature, Wound Response Indicator and Mammostrat. Two of these (Oncotype DX and MammaPrint) are already incorporated in several diagnostic protocols. However, multiple unsolved issues deteriorate the value of these tests: generally the validation is poor, the gene sets do not confirm each other, the associated costs are high and the necessary bioinformatics is highly complex.

The current most powerful prognostic model in Multiple Myeloma (MM) combines beta-2 microglobulin (b2m) with albumin, corresponding to the International Staging System (ISS). However, the prognosis of patients within the ISS stage I (high albumin and low b2m) may vary. Ki-67 is a nuclear protein associated with cell proliferation. We retrospectively evaluated the percentage of bone marrow plasma cells expressing Ki-67 antigen (Ki-67 index) in a series of 174 untreated MM patients at diagnosis. Median survival was 51, 41 and 20 months respectively, and median Ki-67 index was 3.0%, 6.1% and 6.5% in ISS stages I, II, and III respectively. Independently of ISS, Ki-67 index > or =4% was highly predictive of adverse prognosis. Ki-67 index correlated with markers of intrinsic malignancy and with markers of tumour burden. Within ISS stage I, median survival was of 31 months (RR of death 2.65) in patients with Ki-67 index > or =4%. Eventually, the combination of Ki-67 with b2m produced an efficient prognostic model, which appeared most effective in our series when compared with b2m and KI-67 with chromosome 13 deletion models. In this series, we demonstrated that a proliferation marker provides clear-cut additional survival prognostic information to b2m into the ISS model.

Multiple myeloma is a malignant plasma-cell proliferative disease with an expected 15,270 new cases and 11,070 deaths in the USA in 2004 alone. This accounts for 1% of all malignancies and slightly more than 10% of all hematologic malignancies in Caucasians and 20% in African Americans. The diagnosis is based on the presence of bone pain, anemia, and plasma-cell infiltrate in the bone marrow or within bone lesions. It is essential that the spectrum of plasma-cell proliferative disorders be recognized: monoclonal gammopathy of undetermined significance (MGUS), smoldering (asymptomatic) multiple myeloma (SMM), and active (symptomatic) MM. These distinctions affect important management decisions. Other related disorders include primary systemic amyloidosis, POEMS syndrome, and acquired Fanconi syndrome.

Plasmablastic lymphoma is an aggressive neoplasm that shares many cytomorphologic and immunophenotypic features with plasmablastic plasma cell myeloma. However, plasmablastic lymphoma is listed in the World Health Organization (WHO) classification as a variant of diffuse large B-cell lymphoma. To characterize the relationship between plasmablastic lymphoma and plasmablastic plasma cell myeloma, we performed immunohistochemistry using a large panel of B-cell and plasma cell markers on nine cases of plasmablastic lymphoma and seven cases of plasmablastic plasma cell myeloma with and without HIV/AIDS. The expression profiles of the tumor suppressor genes p53, p16, and p27, and the presence of Epstein-Barr virus (EBV) and human herpes virus type 8 (HHV-8) were also analyzed. All cases of plasmablastic lymphoma and plasmablastic plasma cell myeloma were positive for MUM1/IRF4, CD138, and CD38, and negative for CD20, corresponding to a plasma cell immunophenotype. PAX-5 and BCL-6 were weakly positive in 2/9 and 1/5 plasmablastic lymphomas, and negative in all plasmablastic plasma cell myelomas. Three markers that are often aberrantly expressed in cases of plasma cell myelomas, CD56, CD4 and CD10, were positive in 5/9, 2/5, and 6/9 plasmablastic lymphomas, and in 3/7, 1/5, and 2/7 plasmablastic plasma cell myelomas. A high Ki-67 proliferation index, overexpression of p53, and loss of expression of p16 and p27 were present in both tumors. No evidence of HHV-8 infection was detected in either neoplasm. The only significant difference between plasmablastic lymphoma and plasma cell myeloma was the presence of EBV-encoded RNA, which was positive in all plasmablastic lymphoma cases tested and negative in all plasma cell myelomas. In conclusion, most cases of AIDS-related plasmablastic lymphoma have an immunophenotype and tumor suppressor gene expression profile virtually identical to plasmablastic plasma cell myeloma, and unlike diffuse large B-cell lymphoma. These results do not support the suggestion in the WHO classification that plasmablastic lymphoma is a variant of diffuse large B-cell lymphoma.

In this study we analyzed proliferative activity of myeloma cells and a possible correlation with selected clinical data, histological features and survival in 59 patients with newly diagnosed multiple myeloma (27 females and 32 males, mean age 62 years). Imunohistochemical method was applied using Ki-67 antibody on B5-fixed and paraffin-embedded bone marrow specimens to evaluate growth fraction of myeloma cells. Clinical staging was done according to the Durie-Salmon classification (4 patients had stage I disease, 16 patients stage II and 39 patients stage III). The number of Ki-67+ myeloma cells ranged from 1% to 36% (mean value 7%). In 39 of 59 patients (66.1%) number of Ki-67+ cells was less than 10% (cases with low proliferative index). Ki-67 expression significantly correlated with the clinical stage, beta2-microglobulin level, plasma cell morphology, volume of myeloma infiltration and the extent of osteolytic lesions. Patients with increased proliferative index (Ki-67+ cells > or = 10%) showed a significantly shorter survival compared to those with low proliferative index (14 months vs. 36 months, p = 0.023). However, this difference was not shown in multivariate analysis, particularly due to the high correlation between proliferative activity and plasma cell morphology and the volume of myeloma infiltration.

Angiogenesis correlates with disease progression in various haematological malignancies. This study investigated the association between microvascular density (MVD) and the Ki-67 proliferation index (Ki-67 PI), bone marrow infiltration, and C reactive protein (CRP) in patients with multiple myeloma.

Bone marrow MVD was examined in 44 biopsies at diagnosis and 15 in plateau phase by immunostaining the endothelial cells with a monoclonal antibody to CD34. The Ki-67 PI was evaluated by a double immunostaining technique using the monoclonal antibodies MIB-1 and CD38.

MVD, Ki-67 PI, bone marrow infiltration, and CRP were significantly higher in pretreatment patients than in controls and decreased in patients achieving plateau phase. MVD significantly correlated with Ki-67 PI and infiltration, and Ki-67 correlated with infiltration.

In multiple myeloma, apart from being a marker of proliferative activity, Ki-67 is also associated with bone marrow angiogenesis and tumour burden.

The nuclear protein Ki-67 is a proliferation index, as it is expressed only by dividing cells. In this study, we investigated the clinical significance of Ki-67 determination on bone marrow biopsies of 35 patients with newly diagnosed multiple myeloma (MM). We examined the correlation of Ki-67 with other MM proliferation-related factors: interleukin-6 (IL-6), IL-10, bone marrow infiltration by plasma cells, serum lactate dehydrogenase (LDH), and beta 2 microglobulin (b2M). Ki-67 expression was also correlated with the survival rate of the patients. The results showed that Ki-67 expression increases with increasing stage of disease according to Durie-Salmon (classification stage III vs. I and II, p < 0.001). Furthermore, infiltration, IL-6, LDH, and b2M increase significantly with advancing stage of disease (p < 0.004). All parameters studied were significantly higher in patients versus controls. Ki-67 correlated with IL-6 (r: 0.422, p < 0.01), LDH (r: 0.437, p < 0.01), and b2M (r: 0.478, p < 0.004). There was a marked difference in survival between patients with MM with Ki-67 greater than 8% and patients with Ki-67 less than 8%, in favor of the latter (p < 0.07). We conclude that Ki-67 determination during routine pathological analysis of bone marrow in newly diagnosed MM could provide useful information about the proliferative activity and prognosis of the disease.

The application of immunohistology to the spectrum of plasma cell disorders has yet to be incorporated widely into routine haematology practice. This technique enables the direct visualisation of specific surface and cytoplasmic antigens in the context of the individual cell and the surrounding anatomical neighbourhood. This review outlines the role of bone marrow immunohistology in the laboratory evaluation of patients with suspected and established plasma cell neoplasms and its emerging role in understanding myeloma biology for possible future therapeutic application.

Plasma cell neoplasia occurs much less frequently than high-grade B-cell non-Hodgkins lymphoma in HIV-infected patients, but is nevertheless an AIDS-associated malignancy. In this report, we describe the fine-needle aspiration (FNA) findings of a mass in the left parotid region with plasmablastic features that occurred in a 41-yr-old HIV-infected homosexual man whom we diagnosed as having anaplastic myeloma. The patient had normochromic, normocytic anemia with a hematocrit of 21%, a white blood count of 2.2 x 10(9)/l with 76% neutrophils, and a CD4 count of 31%. He also had elevated levels of calcium (13.2 mg/dl), alkaline phosphatase (25,400 IU/l), blood urea nitrogen (2,600 mg/dl), and creatinine (2.5 mg/dl). Serum protein electrophoresis showed polyclonal hypergammaglobulinemia without any monoclonal component. A bone survey revealed multiple punched-out lytic lesions. FNA smears showed large plasmacytoid cells with eccentrically placed nuclei, prominent nucleoli, and moderate amounts of basophilic cytoplasm. By immunocytochemical staining, tumor cells were negative for CD19, CD20, and leukocyte-common antigen (LCA), but strongly positive for CD38 and kappa light chain. Anaplastic myeloma and plasmablastic lymphoma were considered in the differential diagnosis. Although the cytomorphologic and immunophenotypic findings of our case overlapped with those of plasmablastic lymphoma, the pattern of bone involvement with punched-out lytic lesions and absence of localization of the tumor to the mucosa of the oral cavity led us to a diagnosis of anaplastic myeloma. The patient initially received antiretroviral therapy followed by thalidomide and pulse dexamethasome therapy, but his response was poor. His HIV load increased, and his malignancy rapidly progressed with the development of multiple vertebral lesions, extraosseous extension, and eventually cord compression. He died of the disease less than 2 mo after presentation.

Complete or partial deletion of chromosome 13 or translocations involving 13q (delta13) by conventional cytogenetic analysis confers a poor prognosis in multiple myeloma (MM) patients, even with timely application of tandem autologous transplants. It was recently suggested that the prognostic significance of delta13 is related to its frequent association with hypodiploidy but by itself does not have a poor prognostic significance. We therefore analysed our experience in 1475 consecutive MM patients in whom we intended treatment with tandem transplants after a melphalan-based conditioning regimen. Patients with abnormal cytogenetic analysis were grouped into hypodiploid/hypotetraploid, pseudodiploid and hyperdiploid groups, according to their modal chromosome number. Their event-free and overall survival were compared with those of patients with a normalkaryotype. Both hypodiploidy and delta13 were found to independently confer poor prognosis in MM patients. Furthermore, these parameters in combination with easily obtained pretransplant levels of beta-2 microglobulin and albumin define three groups of MM patients with clearly distinct outcomes.

According to the widely accepted myeloma staging system, the bulk of paraprotein is the main determinant of disease stage. However, myelomatous plasma cells differ considerably in their ability to synthesize and secrete monoclonal paraprotein. We determined plasma cell secreting potential (PCSP) as the amount of M-component, divided by the percentage of marrow plasmacytic infiltration, in 240 patients with myeloma, and correlated our results with chain isotype, plasma cell morphology, severity of bone disease, well-recognized prognostic factors, such as serum LDH, CRP, albumin and beta2-microglobulin, treatment response and overall survival. PCSP was higher in IgG than in other myeloma types, and was an almost constant parameter for each individual patient, in 134/166 cases. A > 10% decrease of PCSP in 26 patients was associated with disease aggressiveness and treatment failure. Patients with MGUS had significantly higher PCSP than those with myeloma of the same chain type. Higher PCSP was associated with stage I, absence of Bence-Jones proteinuria and indolent forms of disease with lower proliferating cell nuclear antigen (PCNA) positivity, serum LDH, alpha2-globulins, CRP and beta2-microglobulin and higher albumin levels. Conversely, patients with immature/plasmablastic morphology and those with severe bone disease had lower PCSP. Good responders to treatment had significantly higher PCSP than moderate and poor responders and PCSP was strongly correlated with overall survival in IgG and IgA myeloma. In conclusion, PCSP reflects the maturation status of myelomatous cells and therefore can be used as a prognostic factor, since patients with high secreting potential represent a lower malignancy group, in comparison to those with a low secreting potential.

Abnormalities involving proliferation, apoptosis, and angiogenesis are important in tumorigenesis. The purpose of this study was to examine these three biological processes, and their relation with the clinical stage and cytological grade in multiple myeloma (MM).

Fifty four newly diagnosed patients with MM were studied by immunohistochemistry using bone marrow clot sections. Proliferation and apoptosis were evaluated for the proportion of MM cells (indicated by morphology and CD138 reactivity) positive for the Ki67 antigen and single stranded DNA (ssDNA), respectively. Angiogenesis was evaluated by measuring the intratumoral microvessel density (IMVD) and by assessing the immunoreactivity of vascular endothelial growth factor (VEGF).

There were 30 men and 24 women (median age, 65 years; range, 37-84). At initial presentation, 15 (28%) were in Durie stage I, 15 (28%) in stage II, and 24 (44%) in stage III. Advanced clinical stage correlated with high cytological grade (p < 0.03). The medians for Ki67, ssDNA, and IMVD were 4.4% (range, 0-15%), 0.2% (range, 0-2.8%), and 15.5 (range, 0-63), respectively. Among these three continuous parameters, the only significant correlation was that between Ki67 and IMVD (p < 0.0001). Both Ki67 and IMVD also correlated with the clinical stage, cytological grade, and VEGF positivity (p <0.05). No correlation was found between ssDNA and all of the other parameters.

These data suggest that proliferation is associated with angiogenesis in MM. Furthermore, proliferation and angiogenesis, but not apoptosis, may be important in disease progression. Lastly, increased production of VEGF may be one of the contributing factors to the increase in intratumoral vascularity seen in advanced MM.

Intracranial plasmacytomas are rare lesions that can arise from the calvarium, dura, or cranial base and exhibit a benign course unless associated with myeloma. Attention has recently been focused on the role of the cell adhesion molecules CD56 and CD31 in the pathogenesis of myeloma. No such information is available for intracranial plasmacytomas and myeloma-associated lesions.

We investigated the relationship between CD56 and CD31 expression, intracranial location, and progression to myeloma for a series of nine intracranial plasmacytomas (three dural, one calvarial, and five cranial base lesions). These parameters were also correlated with proliferation indices, as assessed by MIB-1 immunostaining of the histological sections. A single pathologist (AO) performed immunohistochemical analyses and reviewed all slides.

Intracranial plasmacytomas presented more commonly in female patients (89%). The three dural lesions were CD56- and CD31-negative and exhibited MIB-1 staining of less than 10%; no patient developed myeloma or recurrence. Of the five cranial base lesions, three were CD56-positive, none was CD31-positive, and two exhibited MIB-1 labeling of more than 45%, with plasmablastic morphological features. Compared with other intracranial plasmacytomas, five of five patients with cranial base lesions developed bone marrow biopsy-proven myeloma (P < 0.05) within 8 months. The calvarial lesion was CD56- and CD31-positive, and the patient developed myeloma soon after diagnosis. Both of the two highly proliferative plasmablastic lesions recurred, one after gross total resection without radiotherapy and the other after a biopsy and 2000-cGy radiotherapy.

Among intracranial plasmacytomas, cranial base location was the strongest predictor of the development of multiple myeloma. Expression of the cell adhesion molecules CD31 and CD56 was not predictive of outcome. Extramedullary dural-based lesions were CD56-negative and were not associated with myeloma. A high proliferation index and plasmablastic morphological features were predictive of a short time to recurrence and aggressive behavior. We recommend 4050- to 5040-cGy fractionated radiotherapy for all intracranial plasma cell neoplasms and gross total resection for non-cranial base lesions.

The expression of the human Ki-67 protein is strictly associated with cell proliferation. During interphase, the antigen can be exclusively detected within the nucleus, whereas in mitosis most of the protein is relocated to the surface of the chromosomes. The fact that the Ki-67 protein is present during all active phases of the cell cycle (G(1), S, G(2), and mitosis), but is absent from resting cells (G(0)), makes it an excellent marker for determining the so-called growth fraction of a given cell population. In the first part of this study, the term proliferation marker is discussed and examples of the applications of anti-Ki-67 protein antibodies in diagnostics of human tumors are given. The fraction of Ki-67-positive tumor cells (the Ki-67 labeling index) is often correlated with the clinical course of the disease. The best-studied examples in this context are carcinomas of the prostate and the breast. For these types of tumors, the prognostic value for survival and tumor recurrence has repeatedly been proven in uni- and multivariate analysis. The preparation of new monoclonal antibodies that react with the Ki-67 equivalent protein from rodents now extends the use of the Ki-67 protein as a proliferation marker to laboratory animals that are routinely used in basic research. The second part of this review focuses on the biology of the Ki-67 protein. Our current knowledge of the Ki-67 gene and protein structure, mRNA splicing, expression, and cellular localization during the cell-division cycle is summarized and discussed. Although the Ki-67 protein is well characterized on the molecular level and extensively used as a proliferation marker, the functional significance still remains unclear. There are indications, however, that Ki-67 protein expression is an absolute requirement for progression through the cell-division cycle.

There is significant variation in the survival of patients with myeloma. This article reviews the major prognostic factors in myeloma and the evidence supporting their usefulness in clinical practice and research. The factors reviewed include serum beta 2-microglobulin, bone marrow plasma cell labeling index, cytogenetics, plasmablastic morphology, and other standard clinical laboratory variables. Novel factors such as bone marrow angiogenesis are also discussed. A combination of independent factors provides greater prognostic information than any one factor alone, and survival data using various combinations of prognostic factors are presented.

Here the current studies in cell DNA content of plasma cells (PC), from multiple myeloma (MM) patients is reviewed, focusing on two complementary aspects the detection of clonal abnormalities and the identification of the proliferative rate of PC. There is accumulating evidence that the measurement of cell DNA content by flow cytometry (FCM) is a useful parameter in the clinical evaluation of MM patients. Between 50 and 70% of MM patients display DNA aneuploidy, the majority of them being hyperdiploid. Comparing hyperdiploid with diploid patients, the former seem to display a better prognosis. Fluorescence in situ hybridization studies have confirmed that there is a high incidence of numerical chromosome abnormalities in MM and that trisomies are significantly more common than monosomies (84% vs 14%). The most frequent gains can be seen in chromosome 9 and 15 while the most common monosomies are those of chromosome 13 and X in females. The possibility of analysing the cell cycle distribution by using a propidium iodide (PI)/CD38 double staining technique may be an alternative to other more laborious methods of assessing the PC labelling index. Thus, patients with > 3% S-phase PC detected by FCM have an adverse prognosis and this parameter is one of the most important independent prognostic criteria for predicting survival in MM patients. Moreover, the number of S-phase PC, together with other prognostic factors, such as beta 2microglobulin, age and performance status can be a very useful tool for stratifying patients into groups in order to establish risk-directed therapeutic protocols.

The correlation between the bromodeoxiuridine (BrdU)-labelling index (LI) of plasma cells and a new proliferation marker, the Argyrophilic Nucleolar Organizer Regions (AgNORs), was investigated in 44 myeloma patients at diagnosis. A preliminary analysis was made to verify the reproducibility of the assessment of plasma cell infiltration (PC%) in bone marrow aspirates, used to collect cells for LI determination, and in bone marrow biopsies, used for AgNORs evaluation. Although an overall good correlation was observed between PC% in biopsies and aspirates (r=0.58, p=0.001), the ratio between PC% in biopsies and in aspirates ranged form 0.35 to 7.5. Only 17 patients (38.6%) were within the 0.5-1.5 range. A positive correlation between LI and AgNORs was observed in these patients (r=0.68, p=0.003), whereas the correlation was lost in patients with higher ratio between PC% in biopsies and in aspirates (r=0.08, p=0.69). The prognostic significance of AgNORs was confirmed by survival analysis, showing a reduced survival for patients with high (>4.4) AgNOR counts (14 months vs 35 months, p=0.004). The AgNORs analysis therefore allows the simultaneous evaluation of myeloma cell infiltration, degree of differentiation and kinetics of growth in bone marrow biopsies. AgNOR counts deserve to be included in the procedures for diagnosis and prognostic evaluation of myeloma patients.

In this paper three different areas of the biology of multiple myeloma (MM) are reviewed: (1) the immunophenotypic characteristics of plasma cells (PC), (2) the changes in the immunoregulatory cells, and (3) the cell DNA content of PC. Myelomatous PC display a heterogeneous phenotype not only between different patients but also within each patient consistent with the fact that the neoplastic clone is able to undergo a certain degree of differentiation. In addition, PC generally lack surface B cell associated antigens and infrequently show reactivity for non-lineage restricted markers. The B-B4 and CD38 are the two best markers for identifying PC which are crucial for the correct assessment of other antigens by multiple staining procedures. Moreover, some of the antigens present in PC such as CD56, CD20, CD10, CD28 and SIg may have prognostic implications. Whether or not normal PC are phenotypically different from myelomatous PC remains controversial although some antigenic combinations such as CD19-/CD56++ could probably help to identify the malignant nature of PC. Both T and NK cells are markedly altered in MM patients probably reflecting a host-tumour immunological interaction. The reduction in CD4 cells correlates both with advanced clinical stage and poor survival. As far as NK cells are concerned, there is an overall increase in peripheral blood and BM in MM patients but the changes observed are heterogeneous, reflecting the existence of different NK cell subsets. This fact could explain the contradictory results observed in the literature. Accumulating evidence exists that the measurement of cell DNA content by flow cytometry is a useful parameter in the clinical evaluation of MM patients. Between 50 and 70% of MM patients display DNA aneuploidy with the majority of them hyperdiploid. Upon comparing hyperdiploid with diploid patients, the former usually display a better prognosis. The possibility of analysing the cell cycle distribution by using a PI/CD38 double staining technique may be an alternative to other more laborious methods of assessing the PC labelling index. In our experience, patients with > 3% S phase PC have an adverse prognosis and this parameter was the most important independent prognostic criteria for predicting survival.

In this study the incidence of DNA aneuploidy in a large series of untreated multiple myeloma (MM) patients was assessed in order to determine its clinical and prognostic significance. A total of 156 MM patients were included in the study. DNA measurements were performed in all cases at diagnosis using two different flow cytometry methods: (1) propidium iodide (PI) staining on isolated nuclei, and (2) CD38/PI double staining on whole cells. The DNA ploidy status was correlated with the most relevant clinical and haematological disease characteristics. From the 156 cases analysed, 91 (58%) were aneuploid (56% hyperdiploid and 2% hypodiploid). The correlation between the two techniques on the detection of DNA aneuploidy was excellent, although CD38/PI double staining would be preferable in cases with < 5% of DNA aneuploid plasma cells (PC). Upon comparing the clinical and haematological disease characteristics of hyperdiploid versus diploid cases, the former group was characterized by a lower age, reduced incidence of anaemia, lower beta 2M levels, higher proliferative activity within the residual normal haemopoietic cells, increased expression of CD56 antigen in PC, and higher proportion of PB CD4+ T cells. In contrast, diploid cases had a higher expression of the CD10, CD20 and CD15 antigens and greater numbers of PB CD56+CD3- NK cells (P < 0.05). Circulating PC were identified in six cases, all being diploid. Overall survival was significantly longer in hyperdiploid compared to diploid MM (P = 0.02). These results show that over 50% of MM patients are aneuploid, almost all of them being hyperdiploid. This characteristic is associated with better prognosis.

To review biologic factors that may be useful in determining prognosis in patients with myeloma.

The currently available clinical variables and staging systems were assessed for their predictive value in myeloma, and newly proposed prognostic factors were summarized.

Because some patients with myeloma may potentially benefit by new, more intensive therapies such as stem cell transplantation or may have prolonged survival with standard therapy, determining factors that would distinguish such patients is important. Independent prognostic factors such as the plasma cell labeling index and beta 2-microglobulin have repeatedly outperformed other prognostic clinical variables and can be combined into a system that identifies poor, intermediate, and good prognostic groups of patients with myeloma. New factors are needed to improve on the predictive value of these two variables. Studies of the biologic features of myelomas have led to the discovery of soluble interleukin 6 receptor (sIL 6R) in the serum. sIL 6R enhances the myeloma cell response to interleukin 6, a central growth factor that affects myeloma cell proliferation. Preliminary studies by the Eastern Cooperative Oncology Group show that sIL 6R predicts survival independent of the plasma cell labeling index and beta 2-microglobulin. Other proposed independent prognostic factors include cytokines and their soluble receptors, regulatory T cells, circulating myeloma cells, myeloma cell precursors, and markers of proliferation, apoptosis, and drug resistance.

Because of wide variation in duration of survival, the prognosis of patients with myeloma, a fatal bone marrow plasma cell neoplasm, cannot yet be adequately predicted. Better prognostic factors are needed for stratification in clinical trials, counseling of patients, and designing of new therapeutic trials.

This study aimed at optimizing the conditions for flow cytometric detection of myeloperoxidase (MPO), cytoplasmic CD3 (cCD3), and cytoplasmic CD22 (cCD22), which seem to be more reliable lineage-associated markers in acute leukemia than surface antigens. Fixation methods employing saponin as detergent resulted in accurate detection of MPO and cCD3, whereas cCD22 was detectable only after buffered-formaldehyde-acetone fixation. MPO was detected in 16/17 AML, but only in 1/6 ALL, the MPO positive ALL being also CD13 positive. MPO was detectable in 3/4 AML with T-lymphoid features; a case of myeloid antigen-positive T-ALL, however, was MPO-negative. cCD3 was expressed only in T-ALL, and five cases of lymphoid antigen-positive AML were cCD3-negative. We suggest that these flow cytometric assays are useful for the lineage assignment of poorly differentiated leukemias and contribute to the identification of truly biphenotypic acute leukemias.