Kagawa S, Shigeyasu K, Ishida M, Watanabe M, Tazawa H, Nagasaka T, Shirakawa Y, Fujiwara T. Molecular diagnosis and therapy for occult peritoneal metastasis in gastric cancer patients. World J Gastroenterol 2014; 20(47): 17796-17803
Corresponding Author of This Article
Shunsuke Kagawa, MD, PhD, Associate Professor, Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan. email@example.com
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Shunsuke Kagawa, Kunitoshi Shigeyasu, Michihiro Ishida, Megumi Watanabe, Hiroshi Tazawa, Takeshi Nagasaka, Yasuhiro Shirakawa, Toshiyoshi Fujiwara, Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama 700-8558, Japan
ORCID number: $[AuthorORCIDs]
Author contributions: Kagawa S wrote the manuscript; Shigeyasu K, Ishida M, Watanabe M and Tazawa H contributed to review and interpretation of the literatures; Nagasaka T, Shirakawa Y and Fujiwara T supervised the review; all authors have read and approved the final version to be published.
Supported by Grants from Ministry of Education, Science, and Culture, Japan (to Kagawa S) and JSPS KAKENHI, No. 23591932
Correspondence to: Shunsuke Kagawa, MD, PhD, Associate Professor, Department of Gastroenterological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan. firstname.lastname@example.org
Telephone: +81-86-2357257 Fax: +81-86-2218775
Received: April 16, 2014 Revised: June 7, 2014 Accepted: June 25, 2014 Published online: December 21, 2014
To apply an individualized oncological approach to gastric cancer patients, the accurate diagnosis of disease entities is required. Peritoneal metastasis is the most frequent mode of metastasis in gastric cancer, and the tumor-node-metastasis classification includes cytological detection of intraperitoneal cancer cells as part of the staging process, denoting metastatic disease. The accuracy of cytological diagnosis leaves room for improvement; therefore, highly sensitive molecular diagnostics, such as an enzyme immunoassay, reverse transcription polymerase chain reaction, and virus-guided imaging, have been developed to detect minute cancer cells in the peritoneal cavity. Molecular targeting therapy has also been spun off from basic research in the past decade. Although conventional cytology is still the mainstay, novel approaches could serve as practical complementary diagnostics to cytology in near future.
Core tip: For patients with gastric cancer, cytological detection of cancer cells in the peritoneal cavity is important to predict future manifestation of peritoneal recurrence. However, its improvement has been a matter of research, because of its low sensitivity and specificity. The new diagnostic modalities have been investigated along with the development of modern molecular biology. The recent innovative challenges regarding molecular diagnosis of intra-peritoneal gastric cancer cells have been thoroughly covered and summarized. The new therapies for gastric cancer with peritoneal spreads were also referred.
Citation: Kagawa S, Shigeyasu K, Ishida M, Watanabe M, Tazawa H, Nagasaka T, Shirakawa Y, Fujiwara T. Molecular diagnosis and therapy for occult peritoneal metastasis in gastric cancer patients. World J Gastroenterol 2014; 20(47): 17796-17803
Gastric cancer is one the leading causes of death in the world, and the most prevalent cancer in Eastern Asia. Although the radical resection of cancerous lesions is the only cure for gastric cancer, multi-disciplinary therapy for advanced disease can palliate the disease and even prolong life[3,4]. Therefore, the accurate and appropriate diagnosis of the disease entity is required so that an individualized oncological approach can be used. The tumor-node-metastasis (TNM) staging system is the universally accepted method to describe the degree of cancer advancement[5,6]. As with other cancers, gastric cancer has disease-specific factors in its staging. One of them is the cytology of a peritoneal wash or ascites because peritoneal metastasis is the most frequent mode of distant metastasis and post-surgical recurrence. However, it is often difficult to diagnose peritoneal metastasis by conventional imaging modalities, such as computed tomography and positron emission tomography. The cytological detection of free cancer cells in the peritoneal cavity is a very important finding in gastric cancer. Positive cytology means that peritoneal metastasis exists anywhere in the peritoneal cavity even if it is invisible, so it implies a high probability of future manifestations of peritoneal metastasis[7-12]. Therefore, peritoneal lavage cytology findings as well as peritoneal metastasis are factors in gastric cancer staging in Japan as stage 4 disease. The most recent TNM classification system includes intraperitoneal cancer cell detection as part of the staging process, denoting metastatic disease.
Peritoneal carcinomatosis is an incurable disease with poor prognosis. In cases of peritoneal carcinomatosis, although debate about surgical application still remains, palliative chemotherapy would be preferred[14-17]. From this point of view, peritoneal carcinomatosis needs to be precisely diagnosed before surgery or at the beginning of surgery for surgeons to determine the most appropriate therapeutic approach. However, in reality, the uneven shape of the peritoneal cavity makes it impossible for the entire cavity to be thoroughly inspected and difficult for the surgeon to definitively judge whether the peritoneal cavity is completely free of metastatic foci. Consequently, peritoneal lavage cytology is needed for the indirect diagnosis or prediction of peritoneal metastasis, and it must be as accurate as possible. The accuracy in peritoneal lavage cytology depends greatly upon the experience of the cytopathologist; therefore, the diagnosis remains inevitably subjective. In addition, several studies indicate that the sensitivity and specificity of peritoneal lavage cytology is unsatisfactory and that there is still room for improvement. Over the past decade, several new diagnostic approaches have been studied. As an alternative to conventional cytology by Papanicolaou staining, immunocytochemistry or PCR-based genetic detection of epithelial or malignant cells in the peritoneal fluid has emerged (Table 1). There are advantages and shortcomings of each approach. In this review, we examine recent studies, summarize findings on the molecular biology-based diagnosis of peritoneal cancer cell existence, and discuss recent advances in the treatment of peritoneal carcinomatosis.
Table 1 List of published studies regarding the molecular diagnosis of peritoneal fluid in gastric cancer.
Since the method of lavage cytology was described by Moore et al in 1961, several clinical studies have demonstrated the prognostic significance of intraperitoneal free cancer cells at the time of surgery[7,10,12,16,17,22-25]. The Japanese Classification of Gastric Carcinoma (2nd English edition) first included the result of peritoneal cytology as one of the staging parameters in 1999; since then, the Japanese Gastric Cancer Association includes peritoneal cytology in their staging system. Although the most recent TNM classification has included the detection of intraperitoneal free cancer cells as part of the staging process, denoting M1 disease, the application of peritoneal cytology in preoperative staging is still controversial. The European Society for Medical Oncology practice guidelines recommend laparoscopy, but regard cytology as optional, and the current National Comprehensive Cancer Network (NCCN) guidelines also do not include cytology in the treatment algorithm. Nevertheless, peritoneal cytology has important clinical implications in the management of advanced gastric cancer[7,28].
In gastric cancer surgery, by either laparotomy or laparoscopic approach, about 100-200 mL of saline is usually instilled into the Douglas pouch (and occasionally into the left subphrenic space) and gently stirred. A washing sample is then aspirated and subjected to cytology. Traditionally, Papanicolaou or Giemsa stainings are employed, and specimens are diagnosed by experienced cytopathologists. The accuracy, sensitivity, and specificity of conventional cytology in predicting peritoneal recurrence was 73.0%-91.9%, 11.1%-80.0%, and 86.4%-100.0%, respectively. Thus, sensitivity had a particularly wide range, which indicated the need for further advanced techniques.
CARCINOEMBRYONIC ANTIGEN IN PERITONEAL LAVAGE
Kanetaka et al recently reported that the measurement of carcinoembryonic antigen (CEA) level in peritoneal lavage (pCEA) by an enzyme immunoassay can predict poor prognosis and may help to elucidate a cohort who need more intensive adjuvant chemotherapy to improve their prognosis. Since Asao et al first reported that the CEA antigen level in peritoneal lavage could reflect the presence of peritoneal metastasis more accurately than conventional cytology in 1991, other investigators have demonstrated the clinical significance of pCEA levels[31-35]. Most of these reports showed a significant correlation between pCEA level and survival after surgery, implying that pCEA could be a potential predictor of poor prognosis. However, the pCEA level may reflect both the production of CEA in the peritoneal cavity and the serum CEA level and may not be specific as a marker for the existence of intraperitoneal free cancer cells or occult peritoneal metastasis.
GENETIC DETECTION OF INTRAPERITONEAL GASTRIC CANCER CELLS
Molecular diagnosis with reverse transcriptase-polymerase chain reaction (RT-PCR) has been employed for the detection of minimal cancer cells due to its high sensitivity. Among the messenger RNA (mRNA) specific to cancer cells or epithelial cells, the most common target molecule is CEA mRNA. PCR evaluation of CEA mRNA in peritoneal fluid has increased sensitivity for the detection of peritoneal cancer cells as compared to cytology[36,37], and positive results have been associated with poor survival. Kodera et al demonstrated that CEA PCR-positive patients had significantly worse overall survival and recurrence-free survival as compared to PCR-negative patients, independently of cytology. PCR appears to increase the accuracy of detection of occult disease.
In addition, molecular targets for PCR other than CEA have been investigated and include metalloprotease-7 and cytokeratin 20[40,41]. The expression level of a single gene was heterogeneous, so limited sensitivity hinders its use alone. To further improve the sensitivity and specificity of the mRNA detection approach, multiplex PCR may prove to be more clinically useful in capturing intraperitoneal free cancer cells[41-43].
Mori et al tried to select marker candidates out of tens of thousands of genes with microarray analysis, and they identified the genes specific to cytology-positive samples. They further manufactured a microarray chip containing 10 marker genes as a “MiniChip” and demonstrated that the MiniChip assay has a sensitivity and specificity equal to or better than conventional cytology in detecting minimal free cancer cells in peritoneal fluid.
Recently, a new rapid genetic diagnostic technique to detect minute cancer cells has been developed and applied in the sentinel node navigation surgery as surgical decision making[45-48]. One-step nucleic acid amplification (OSNA) uses reverse transcription loop-mediated isothermal amplification (RT-LAMP) to detect mRNA expression of target sequences from crude samples without RNA purification. The reaction can be completed in a single test tube and within 1 h. Kumagai et al reported a multicenter study evaluating the clinical performance of the OSNA assay that detects cytokeratin 19 (CK19) mRNA in detecting lymph node (LN) metastases in gastric cancer patients, and this method showed high concordance rate to pathology. Although the OSNA assay is useful in the intraoperative rapid diagnosis of LN metastasis for gastric cancer, it remains unproven if this technique could be applied to detect intra-peritoneal free cancer cells. It needs to be determined how the different properties of cells in the peritoneal cavity interfere with the reaction and what the minimal number of cancer cells is for detection by this method.
DNA methylation is an important epigenetic change in cancer that leads to the recruitment of transcription repressors and chromatin changes, so methylation analysis has been used as a diagnostic modality for various cancers. Hiraki et al[52,53] assessed whether gene methylation in peritoneal ﬂuid from gastric cancer patients is clinically feasible for determining the peritoneal metastasis in gastric cancer. By using quantitative methylation-specific PCR to compare aberrant methylation status in gastric cancer, they isolated 6 genes (BNIP3, CHFR, CYP1B1, MINT25, RASSF2 and SFRP2) as having cancer-speciﬁc DNA methylation, and they observed that there was a significant correlation between positive methylation in any of these 6 genes and peritoneal recurrence. Thus, methylation analysis might improve the positive detection of gastric cancer cells in peritoneal lavage.
TELOMERASE ACTIVITY IN THE PERITONEAL FLUID
Telomerase activity in cancer cells has been examined as a tag to detect cancer cells in the peritoneal cavity. Telomerase activity is one of the hallmarks of cancer and can be used to discriminate malignant cells from normal ones[54,55]. Mori et al analyzed peritoneal lavage fluid employing a TRAP assay that reflects telomerase activity. To improve the efficacy of the assay, they enriched cancer cells with immunomagnetic beads coated with anti-Ber-EP4 antibody. Then, they successfully detected telomerase activity in the samples from gastric cancer patients with serosal or subserosal invasions, and they found some concordance with the results of cytology. Da et al have also investigated the telomerase activity in peritoneal lavage from gastric cancer patients without enrichment of cancer cells. Although the sample size was relatively small, their data demonstrated that all patients with peritoneal metastasis had detectable telomerase activity in peritoneal lavage fluid, and they found significant correlations between positive rate of telomerase activity and invasion depth, serosa-involved areas, and the presence and extent of peritoneal metastasis. While these methods were unique and appeared to be sensitive, they were not significantly superior to conventional cytology by itself. Nevertheless, telomerase activity analysis in peritoneal lavage fluid might be a helpful adjunct for the cytology in the diagnosis of occult peritoneal metastasis of gastric cancer.
FLOW CYTOMETRIC ANALYSIS OF FREE CANCER CELLS IN PERITONEAL LAVAGE FLUID
Kitayama et al tried to quantify the free cancer cells recovered from ascites or peritoneal lavage fluid from gastric cancer patients by conventional flow cytometry. The peritoneal lavage fluid from gastric cancer patients contains erythrocytes, leukocytes, dissociated peritoneal mesothelium, and a small number of cancer cells. Therefore, molecular detection needs to distinguish cancer cells from normal cells co-existing in the peritoneal cavity. Kitayama et al stained the cells with monoclonal antibodies to CD45 and CD326 (EpCAM), and CD326-positive and CD45-positive cells were classified as either cancer cell or leukocytes. Instead of using the total number of cancer cells, they calculated the cancer cell/leukocyte ratio and demonstrated that the ratio was significantly higher in the patients with peritoneal metastasis and positive cytology than in those without peritoneal spread. They further showed the ratio to reflect well the effect of intraperitoneal chemotherapy. They thus proposed that the flow cytometry-based measurement of the intraperitoneal CD326(+)/CD45(+) ratio could be a diagnostic marker that reflects the severity of peritoneal metastasis as well as the effectiveness of intraperitoneal chemotherapy.
Besides gastric cancer, ovarian cancer also often forms excess ascites due to peritoneal metastasis, which is routinely drained and discarded for symptomatic relief. Peterson et al regard the ascites as a source of cancer cells for monitoring the treatment response of ovarian cancer. Miniaturizing and advancing flow cytometric technology, they developed and tested a new microfluidic chip to capture, enrich and analyze ascites tumor cells in ovarian cancer patients. This technology allows the detection of occult cancer cells and enables the molecular profiling of individual cells. The microfluidic chip might be applicable to the diagnostic and molecular analysis of peritoneal fluid from gastric cancer patients.
DIAGNOSTIC POTENTIAL OF THE VISUAL DETECTION OF CANCER CELLS IN PERITONEAL CYTOLOGY SAMPLES
As a unique approach, several groups examined virus-mediated fluorescent gene expression to visually detect rare cancer cells in the body fluid or the cytology samples against millions of normal cells[55,60,61]. Wong et al evaluated a novel detection technique for intraperitoneal free cancer cells by using Newcastle disease virus-green fluorescent protein (NDV-GFP), which is genetically modified NDV that expresses the green fluorescent protein gene. Newcastle disease virus has been studied since the 1950s for its ability to infect and replicate specifically in tumors. NDV-GFP targets and infects specifically cancer cells, resulting in specific GFP expression. Wong et al evaluated peritoneal lavage samples from 30 gastric cancer patients undergoing staging laparoscopy with NDV-GFP. They found that NDV-GFP-mediated detection offers a more sensitive method of identifying free peritoneal gastric cancer cells in peritoneal lavage fluid as compared to conventional Pap staining cytology to demonstrate that NDV-GFP could be used diagnostically.
WHAT IS NEXT FOR THE IMPROVEMENT OF INTRAPERITONEAL DIAGNOSIS?
As described above, numerous efforts have been made to improve the detection of intraperitoneal free cancer cells. The purpose of most of these studies appeared to primarily be an improvement of the accuracy in cytology. The secondary purpose will be to make diagnosis more convenient and automatic than subjective conventional cytology. Once the accuracy and procedure is essentially improved over the conventional cytology, what should we do next? The identification of intraperitoneal free cancer cells confers poor prognosis. In patients with positive cytology without macroscopic peritoneal metastasis, the benefit of radical or aggressive surgery is still a matter of debate. While some of these patients are palliated, others may undergo more aggressive therapies. Along with the improved diagnostic modality, the treatment strategy would also have to be a coupled issue.
MULTIMODAL CLINICAL APPROACH FOR PERITONEAL SPREAD OF GASTRIC CANCER
Surgeons have witnessed some patients with peritoneal spread of gastric cancer who underwent radical surgery and experienced cures due to the recent improvements in multimodal treatment. A phase II study of whether gastrectomy with curative intent would be beneficial for patients with positive cytology but absence of macroscopic peritoneal seeding has been conducted[63,64]. The study showed that median overall survival time was 705 d, and the 5-year survival rate was 26% in the patients with positive cytology with no other non-curative factors, suggesting that surgery with curative intent could be indicated even for patients with positive cytology[63,64]. For gastric cancer patients with macroscopic peritoneal metastasis, Yamaguchi et al evaluated intraperitoneal chemotherapy along with systemic chemotherapy as a phase II study. They reported a 1-year survival rate of 77.1%, which is surprisingly high. The same group also reported salvage gastrectomy after intravenous and intraperitoneal chemotherapy for the patients who had peritoneal metastasis but showed apparent shrinkage of their peritoneal nodules as well as negative cytology by the treatment. Those patients who underwent salvage gastrectomy exhibited a 26.4-mo median survival period and 82% of 1-year overall survival. Those results suggested that the more sensitive and specific peritoneal diagnosis with the molecular approach might allow gastric cancer patients to receive more suitable individualized multimodal therapies.
A NEW MOLECULAR-TARGETING THERAPY FOR INTRAPERITONEAL SPREAD OF GASTRIC CANCER
Along with the research for the improvement in detection of intraperitoneal cancer cells, molecular targeting therapies might be derived from the results of basic research. One of the molecular targets is epithelial cell adhesion molecule (EpCAM), a type I transmembrane glycoprotein functioning as a homotypic intercellular adhesion molecule. High-level EpCAM expression was observed in 90.7% of gastric cancer. Catumaxomab is an artificially engineered, tri-functional bispecific monoclonal antibody; Fab binding sites bind to EpCAM on cancer cells and CD3 on T cells, and the Fc region binds and activates accessory immune cells. The tri-cell complex of T-cells, tumor cells and accessory cells induces MHC-unrestricted but specific efficient tumor cell killing. The therapeutic benefit of Catumaxomab for patients with malignant ascites including gastric cancer patients has been reported in a pivotal clinical trial, which led to approval of Catumaxomab by the European Medicines Agency (EMA) in 2009. Intraperitoneal Catumaxomab treatment has been shown to trigger the activation of immune effector cells in the peritoneal cavity resulting in the depletion of EpCAM-positive tumor cells. Thus, local strategies with molecular targeting agents might represent the appropriate option for treatment of the peritoneal spread of gastric cancer.
In the past decade, enormous strides have been made in the research for molecular detection of intraperitoneal free gastric cancer cells, and many new strategies have been clinically tested in gastric cancer patients. As with the conventional cytology, none of the candidate alternatives to conventional cytology are a perfect modality yet, whereas most of them would potentially be conducive to improve the conventional diagnosis and to predict prognosis. The uncertainty of a definition of positivity in these novel approaches and their clinical relevance remain potential limitations to the practical clinical use of these technologies. Too highly sensitive techniques such as PCR may result in the detection of clinically irrelevant metastatic disease, which could lead to either overtreatment with unnecessary chemotherapy, or worse, the withdrawal of potentially curative surgical treatment. Nevertheless, the development of more sensitive and rapid diagnostics in evaluating minimal peritoneal disease is needed for patients to be properly treated. Since peritoneal lavage cytology has recently been included in the staging criteria of gastric cancer, the cytology diagnosis has been focused on as having an important predictive role in gastric cancer treatment, and the molecular diagnosis has undergone tremendous challenges. With the accumulated evidence, the molecular diagnosis of peritoneal cytology may be a reality in future gastric cancer practice.
P- Reviewer: Bentrem D, Majumdar APN S- Editor: Ding Y L- Editor: A E- Editor: Liu XM
Ferlay J, Shin H, Bray F, Forman D, Mathers C, Parkin D. GLOBOCAN 2008 v2.0, Cancer incidence and mortality worldwide: IARC Cancer Base No.10.
Available from: http://globocan.iarc.fr.
Bray F, Ren JS, Masuyer E, Ferlay J. Global estimates of cancer prevalence for 27 sites in the adult population in 2008.Int J Cancer. 2013;132:1133-1145.
Coburn N, Seevaratnam R, Paszat L, Helyer L, Law C, Swallow C, Cardosa R, Mahar A, Lourenco LG, Dixon M. Optimal management of gastric cancer: results from an international RAND/UCLA expert panel.Ann Surg. 2014;259:102-108.
Brar SS, Mahar AL, Helyer LK, Swallow C, Law C, Paszat L, Seevaratnam R, Cardoso R, McLeod R, Dixon M. Processes of care in the multidisciplinary treatment of gastric cancer: results of a RAND/UCLA expert panel.JAMA Surg. 2014;149:18-25.
Washington K. 7th edition of the AJCC cancer staging manual: stomach.Ann Surg Oncol. 2010;17:3077-3079.
Sobin L GM, Wittekind C. TNM Classiﬁcation of Malignant Tumours, 7th ed. Oxford: Wiley-Blackwell; 2009;.
Lee SD, Ryu KW, Eom BW, Lee JH, Kook MC, Kim YW. Prognostic significance of peritoneal washing cytology in patients with gastric cancer.Br J Surg. 2012;99:397-403.
La Torre M, Ferri M, Giovagnoli MR, Sforza N, Cosenza G, Giarnieri E, Ziparo V. Peritoneal wash cytology in gastric carcinoma. Prognostic significance and therapeutic consequences.Eur J Surg Oncol. 2010;36:982-986.
Nakagohri T, Yoneyama Y, Kinoshita T, Konishi M, Inoue K, Takahashi S. Prognostic significance of peritoneal washing cytology in patients with potentially resectable gastric cancer.Hepatogastroenterology. 2008;55:1913-1915.
Euanorasetr C, Lertsithichai P. Prognostic significance of peritoneal washing cytology in Thai patients with gastric adenocarcinoma undergoing curative D2 gastrectomy.Gastric Cancer. 2007;10:18-23.
Yajima K, Kanda T, Ohashi M, Wakai T, Nakagawa S, Sasamoto R, Hatakeyama K. Clinical and diagnostic significance of preoperative computed tomography findings of ascites in patients with advanced gastric cancer.Am J Surg. 2006;192:185-190.
Kodera Y, Yamamura Y, Shimizu Y, Torii A, Hirai T, Yasui K, Morimoto T, Kato T. Peritoneal washing cytology: prognostic value of positive findings in patients with gastric carcinoma undergoing a potentially curative resection.J Surg Oncol. 1999;72:60-64; discussion 64-65.
Japanese Gastric Cancer Association. Japanese classification of gastric carcinoma: 3rd English edition.Gastric Cancer. 2011;14:101-112.
Japanese Gastric Cancer Association. Japanese gastric cancer treatment guidelines 2010 (ver. 3).Gastric Cancer. 2011;14:113-123.
Mezhir JJ, Shah MA, Jacks LM, Brennan MF, Coit DG, Strong VE. Positive peritoneal cytology in patients with gastric cancer: natural history and outcome of 291 patients.Indian J Surg Oncol. 2011;2:16-23.
Fukagawa T, Katai H, Saka M, Morita S, Sasajima Y, Taniguchi H, Sano T, Sasako M. Significance of lavage cytology in advanced gastric cancer patients.World J Surg. 2010;34:563-568.
Miyashiro I, Takachi K, Doki Y, Ishikawa O, Ohigashi H, Murata K, Sasaki Y, Imaoka S, Nakaizumi A, Takenaka A. When is curative gastrectomy justified for gastric cancer with positive peritoneal lavage cytology but negative macroscopic peritoneal implant?World J Surg. 2005;29:1131-1134.
Mezhir JJ, Posner MC, Roggin KK. Prospective clinical trial of diagnostic peritoneal lavage to detect positive peritoneal cytology in patients with gastric cancer.J Surg Oncol. 2013;107:794-798.
Fujiwara Y, Doki Y, Taniguchi H, Sohma I, Takiguchi S, Miyata H, Yamasaki M, Monden M. Genetic detection of free cancer cells in the peritoneal cavity of the patient with gastric cancer: present status and future perspectives.Gastric Cancer. 2007;10:197-204.
Leake PA, Cardoso R, Seevaratnam R, Lourenco L, Helyer L, Mahar A, Rowsell C, Coburn NG. A systematic review of the accuracy and utility of peritoneal cytology in patients with gastric cancer.Gastric Cancer. 2012;15 Suppl 1:S27-S37.
Moore GE, Sako K, Kondo T, Badillo J, Burke E. Assessment of the exfoliation of tumor cells into the body cavities.Surg Gynecol Obstet. 1961;112:469-474.
Suzuki T, Ochiai T, Hayashi H, Nakajima K, Yasumoto A, Hishikawa E, Shimada H, Horiuchi F, Ohki S, Isono K. Importance of positive peritoneal lavage cytology findings in the stage grouping of gastric cancer.Surg Today. 1999;29:111-115.
Makino T, Fujiwara Y, Takiguchi S, Miyata H, Yamasaki M, Nakajima K, Nishida T, Mori M, Doki Y. The utility of pre-operative peritoneal lavage examination in serosa-invading gastric cancer patients.Surgery. 2010;148:96-102.
Bonenkamp JJ, Songun I, Hermans J, van de Velde CJ. Prognostic value of positive cytology findings from abdominal washings in patients with gastric cancer.Br J Surg. 1996;83:672-674.
Bando E, Yonemura Y, Takeshita Y, Taniguchi K, Yasui T, Yoshimitsu Y, Fushida S, Fujimura T, Nishimura G, Miwa K. Intraoperative lavage for cytological examination in 1,297 patients with gastric carcinoma.Am J Surg. 1999;178:256-262.
Japanese Gastric Cancer Association. Japanese Classification of Gastric Carcinoma - 2nd English Edition -.Gastric Cancer. 1998;1:10-24.
Wu CC, Chen JT, Chang MC, Ho WL, Chen CY, Yeh DC, Liu TJ, P’eng FK. Optimal surgical strategy for potentially curable serosa-involved gastric carcinoma with intraperitoneal free cancer cells.J Am Coll Surg. 1997;184:611-617.
Kanetaka K, Ito S, Susumu S, Yoneda A, Fujita F, Takatsuki M, Kuroki T, Eguchi S. Clinical significance of carcinoembryonic antigen in peritoneal lavage from patients with gastric cancer.Surgery. 2013;154:563-572.
Asao T, Fukuda T, Yazawa S, Nagamachi Y. Carcinoembryonic antigen levels in peritoneal washings can predict peritoneal recurrence after curative resection of gastric cancer.Cancer. 1991;68:44-47.
Abe N, Watanabe T, Toda H, Machida H, Suzuki K, Masaki T, Mori T, Sugiyama M, Atomi Y, Nakaya Y. Prognostic significance of carcinoembryonic antigen levels in peritoneal washes in patients with gastric cancer.Am J Surg. 2001;181:356-361.
Irinoda T, Terashima M, Takagane A, Sasaki N, Abe K, Araya M, Nishizuka S, Yonezawa H, Nakaya T, Shimooki O. Carcinoembryonic antigen level in peritoneal washing is a prognostic factor in patients with gastric cancer.Oncol Rep. 1998;5:661-666.
Yamamoto M, Baba H, Toh Y, Okamura T, Maehara Y. Peritoneal lavage CEA/CA125 is a prognostic factor for gastric cancer patients.J Cancer Res Clin Oncol. 2007;133:471-476.
Cetin B, Atalay C, Aslan S, Babacan B, Hatipoğlu C, Akinci M, Cetin A. Peritoneal carcinoembryonic antigen level for predicting locoregional and distant spread of gastric cancer.Surg Today. 2005;35:919-924.
Li JK, Zheng M, Miao CW, Zhang JH, Ding GH, Wu WS. Peritoneal lavage cytology and carcinoembryonic antigen determination in predicting peritoneal metastasis and prognosis of gastric cancer.World J Gastroenterol. 2005;11:7374-7377.
Wang JY, Lin SR, Lu CY, Chen CC, Wu DC, Chai CY, Chen FM, Hsieh JS, Huang TJ. Gastric cancer cell detection in peritoneal lavage: RT-PCR for carcinoembryonic antigen transcripts versus the combined cytology with peritoneal carcinoembryonic antigen levels.Cancer Lett. 2005;223:129-135.
Dalal KM, Woo Y, Kelly K, Galanis C, Gonen M, Fong Y, Coit DG. Detection of micrometastases in peritoneal washings of gastric cancer patients by the reverse transcriptase polymerase chain reaction.Gastric Cancer. 2008;11:206-213.
Kodera Y, Nakanishi H, Ito S, Yamamura Y, Kanemitsu Y, Shimizu Y, Hirai T, Yasui K, Kato T, Tatematsu M. Quantitative detection of disseminated free cancer cells in peritoneal washes with real-time reverse transcriptase-polymerase chain reaction: a sensitive predictor of outcome for patients with gastric carcinoma.Ann Surg. 2002;235:499-506.
Yonemura Y, Fujimura T, Ninomiya I, Kim BS, Bandou E, Sawa T, Kinoshita K, Endo Y, Sugiyama K, Sasaki T. Prediction of peritoneal micrometastasis by peritoneal lavaged cytology and reverse transcriptase-polymerase chain reaction for matrix metalloproteinase-7 mRNA.Clin Cancer Res. 2001;7:1647-1653.
Kodera Y, Nakanishi H, Ito S, Yamamura Y, Fujiwara M, Koike M, Hibi K, Ito K, Tatematsu M, Nakao A. Prognostic significance of intraperitoneal cancer cells in gastric carcinoma: detection of cytokeratin 20 mRNA in peritoneal washes, in addition to detection of carcinoembryonic antigen.Gastric Cancer. 2005;8:142-148.
Sugita Y, Fujiwara Y, Taniguchi H, Mori T, Ishii T, Niwa H, Okada Y, Takiguchi S, Yasuda T, Yano M. Quantitative molecular diagnosis of peritoneal lavage fluid for prediction of peritoneal recurrence in gastric cancer.Int J Oncol. 2003;23:1419-1423.
Takata A, Kurokawa Y, Fujiwara Y, Nakamura Y, Takahashi T, Yamasaki M, Miyata H, Nakajima K, Takiguchi S, Mori M. Prognostic value of CEA and CK20 mRNA in the peritoneal lavage fluid of patients undergoing curative surgery for gastric cancer.World J Surg. 2014;38:1107-1111.
Mori K, Suzuki T, Uozaki H, Nakanishi H, Ueda T, Matsuno Y, Kodera Y, Sakamoto H, Yamamoto N, Sasako M. Detection of minimal gastric cancer cells in peritoneal washings by focused microarray analysis with multiple markers: clinical implications.Ann Surg Oncol. 2007;14:1694-1702.
Mori K, Aoyagi K, Ueda T, Danjoh I, Tsubosa Y, Yanagihara K, Matsuno Y, Sasako M, Sakamoto H, Mafune Ki. Highly specific marker genes for detecting minimal gastric cancer cells in cytology negative peritoneal washings.Biochem Biophys Res Commun. 2004;313:931-937.
Castellano I, Macrì L, Deambrogio C, Balmativola D, Bussone R, Ala A, Coluccia C, Sapino A. Reliability of whole sentinel lymph node analysis by one-step nucleic acid amplification for intraoperative diagnosis of breast cancer metastases.Ann Surg. 2012;255:334-342.
Matsuzuka T, Takahashi K, Kawakita D, Kohno N, Nagafuji H, Yamauchi K, Suzuki M, Miura T, Furuya N, Yatabe Y. Intraoperative molecular assessment for lymph node metastasis in head and neck squamous cell carcinoma using one-step nucleic acid amplification (OSNA) assay.Ann Surg Oncol. 2012;19:3865-3870.
Tamaki Y, Sato N, Homma K, Takabatake D, Nishimura R, Tsujimoto M, Yoshidome K, Tsuda H, Kinoshita T, Kato H. Routine clinical use of the one-step nucleic acid amplification assay for detection of sentinel lymph node metastases in breast cancer patients: results of a multicenter study in Japan.Cancer. 2012;118:3477-3483.
Yaguchi Y, Sugasawa H, Tsujimoto H, Takata H, Nakabayashi K, Ichikura T, Ono S, Hiraki S, Sakamoto N, Horio T. One-step nucleic acid amplification (OSNA) for the application of sentinel node concept in gastric cancer.Ann Surg Oncol. 2011;18:2289-2296.
Muto Y, Matubara H, Tanizawa T, Nabeya Y, Kawahira H, Akai T, Hoshino I, Hayashi H. Rapid diagnosis of micrometastasis of gastric cancer using reverse transcription loop-mediated isothermal amplification.Oncol Rep. 2011;26:789-794.
Kumagai K, Yamamoto N, Miyashiro I, Tomita Y, Katai H, Kushima R, Tsuda H, Kitagawa Y, Takeuchi H, Mukai M. Multicenter study evaluating the clinical performance of the OSNA assay for the molecular detection of lymph node metastases in gastric cancer patients.Gastric Cancer. 2014;17:273-280.
Nagasaka T, Tanaka N, Cullings HM, Sun DS, Sasamoto H, Uchida T, Koi M, Nishida N, Naomoto Y, Boland CR. Analysis of fecal DNA methylation to detect gastrointestinal neoplasia.J Natl Cancer Inst. 2009;101:1244-1258.
Hiraki M, Kitajima Y, Koga Y, Tanaka T, Nakamura J, Hashiguchi K, Noshiro H, Miyazaki K. Aberrant gene methylation is a biomarker for the detection of cancer cells in peritoneal wash samples from advanced gastric cancer patients.Ann Surg Oncol. 2011;18:3013-3019.
Hiraki M, Kitajima Y, Sato S, Nakamura J, Hashiguchi K, Noshiro H, Miyazaki K. Aberrant gene methylation in the peritoneal fluid is a risk factor predicting peritoneal recurrence in gastric cancer.World J Gastroenterol. 2010;16:330-338.
Kishimoto H, Kojima T, Watanabe Y, Kagawa S, Fujiwara T, Uno F, Teraishi F, Kyo S, Mizuguchi H, Hashimoto Y. In vivo imaging of lymph node metastasis with telomerase-specific replication-selective adenovirus.Nat Med. 2006;12:1213-1219.
Kojima T, Hashimoto Y, Watanabe Y, Kagawa S, Uno F, Kuroda S, Tazawa H, Kyo S, Mizuguchi H, Urata Y. A simple biological imaging system for detecting viable human circulating tumor cells.J Clin Invest. 2009;119:3172-3181.
Mori N, Oka M, Hazama S, Iizuka N, Yamamoto K, Yoshino S, Tangoku A, Noma T, Hirose K. Detection of telomerase activity in peritoneal lavage fluid from patients with gastric cancer using immunomagnetic beads.Br J Cancer. 2000;83:1026-1032.
Da MX, Wu XT, Guo TK, Zhao ZG, Luo T, Qian K, Zhang MM, Wang J. Clinical significance of telomerase activity in peritoneal lavage fluid from patients with gastric cancer and its relationship with cellular proliferation.World J Gastroenterol. 2007;13:3122-3127.
Kitayama J, Emoto S, Yamaguchi H, Ishigami H, Kamei T, Yamashita H, Seto Y, Matsuzaki K, Watanabe T. Flow cytometric quantification of intraperitoneal free tumor cells in patients with peritoneal metastasis.Cytometry B Clin Cytom. 2014;86:56-62.
Peterson VM, Castro CM, Chung J, Miller NC, Ullal AV, Castano MD, Penson RT, Lee H, Birrer MJ, Weissleder R. Ascites analysis by a microfluidic chip allows tumor-cell profiling.Proc Natl Acad Sci USA. 2013;110:E4978-E4986.
Adusumilli PS, Gholami S, Chun YS, Mullerad M, Chan MK, Yu Z, Ben-Porat L, Rusch VW, Fong Y. Fluorescence-assisted cytological testing (FACT): Ex Vivo viral method for enhancing detection of rare cancer cells in body fluids.Mol Med. 2011;17:628-634.
Maida Y, Kyo S, Sakaguchi J, Mizumoto Y, Hashimoto M, Mori N, Ikoma T, Nakamura M, Takakura M, Urata Y. Diagnostic potential and limitation of imaging cancer cells in cytological samples using telomerase-specific replicative adenovirus.Int J Oncol. 2009;34:1549-1556.
Wong J, Schulman A, Kelly K, Zamarin D, Palese P, Fong Y. Detection of free peritoneal cancer cells in gastric cancer using cancer-specific Newcastle disease virus.J Gastrointest Surg. 2010;14:7-14.
Kodera Y, Ito S, Mochizuki Y, Ohashi N, Tanaka C, Kobayashi D, Kojima H, Matsui T, Kondo K, Fujiwara M. Long-term follow up of patients who were positive for peritoneal lavage cytology: final report from the CCOG0301 study.Gastric Cancer. 2012;15:335-337.
Kodera Y, Ito S, Mochizuki Y, Kondo K, Koshikawa K, Suzuki N, Kojima H, Kojima T, Matsui T, Takase T. A phase II study of radical surgery followed by postoperative chemotherapy with S-1 for gastric carcinoma with free cancer cells in the peritoneal cavity (CCOG0301 study).Eur J Surg Oncol. 2009;35:1158-1163.
Yamaguchi H, Kitayama J, Ishigami H, Emoto S, Yamashita H, Watanabe T. A phase 2 trial of intravenous and intraperitoneal paclitaxel combined with S-1 for treatment of gastric cancer with macroscopic peritoneal metastasis.Cancer. 2013;119:3354-3358.
Kitayama J, Ishigami H, Yamaguchi H, Yamashita H, Emoto S, Kaisaki S, Watanabe T. Salvage gastrectomy after intravenous and intraperitoneal paclitaxel (PTX) administration with oral S-1 for peritoneal dissemination of advanced gastric cancer with malignant ascites.Ann Surg Oncol. 2014;21:539-546.
Litvinov SV, Velders MP, Bakker HA, Fleuren GJ, Warnaar SO. Ep-CAM: a human epithelial antigen is a homophilic cell-cell adhesion molecule.J Cell Biol. 1994;125:437-446.
Went P, Vasei M, Bubendorf L, Terracciano L, Tornillo L, Riede U, Kononen J, Simon R, Sauter G, Baeuerle PA. Frequent high-level expression of the immunotherapeutic target Ep-CAM in colon, stomach, prostate and lung cancers.Br J Cancer. 2006;94:128-135.
Heiss MM, Murawa P, Koralewski P, Kutarska E, Kolesnik OO, Ivanchenko VV, Dudnichenko AS, Aleknaviciene B, Razbadauskas A, Gore M. The trifunctional antibody catumaxomab for the treatment of malignant ascites due to epithelial cancer: Results of a prospective randomized phase II/III trial.Int J Cancer. 2010;127:2209-2221.
Jäger M, Schoberth A, Ruf P, Hess J, Hennig M, Schmalfeldt B, Wimberger P, Ströhlein M, Theissen B, Heiss MM. Immunomonitoring results of a phase II/III study of malignant ascites patients treated with the trifunctional antibody catumaxomab (anti-EpCAM x anti-CD3).Cancer Res. 2012;72:24-32.