Primary uterine sarcomas are infrequent neoplasms and most commonly leiomyosarcomas or endometrial stromal sarcomas. We report a rare case of primary uterine osteosarcoma discovered in a woman in her 60s following staging CT imaging for bilateral breast carcinomas. Examination of the subsequent hysterectomy specimen showed a tumour composed of malignant spindle cells and osteoclast-like giant cells associated with osteoid and neoplastic bone, in keeping with primary uterine osteosarcoma. Distinction of osteosarcoma from the more common carcinosarcoma is important due to the worse prognosis impacting on treatment decisions. In addition, synchronous presentation of this unusual tumour with bilateral breast carcinomas raises the possibility of a mutual genetic pathogenesis.

To determine whether cytoreduction is associated with improved outcome in patients newly diagnosed with metastatic uterine leiomyosarcoma (LMS).

We retrospectively identified all patients treated at our institution for high-grade uterine LMS with extrauterine disease at the time of initial diagnosis from 7/1/82 to 7/31/07. Pattern of disease spread was classified as intraperitoneal (IP) or extraperitoneal (EP). Progression-free survival (PFS) and overall survival (OS) were determined from date of initial surgery using Kaplan-Meier estimates.

We identified 96 cases. Median age was 54 years (range, 23-81). IP disease was seen in 48 (50%) and EP in 48 (50%). A complete gross resection of all tumor was achieved in 41/84 (49%). Recurrence or progression was noted in 93 (97%); 81 (84%) have died. Median PFS and OS for the entire cohort was 9.7 months (range, 6.7-10.9) and 20.2 months (range, 15.5-24.8), respectively. All 8 non-surgical cases died within 30 months of diagnosis. Median PFS was 14.2 months (range, 11.4-16.9) for those with a complete gross resection versus 6.8 months (range, 4.1-9.5) for those with any residual disease (P=0.002). Median OS was 31.9 months (range, 3.3-60.4) versus 20.2 months (range, 11.8-28.6), respectively (P=0.04). On multivariate analysis, no residual disease was independently associated with PFS when adjusting for disease distribution (IP vs EP) and the use of chemotherapy but not OS.

Surgical cytoreduction of metastatic uterine LMS was independently associated with PFS but not OS in cases selected for surgery. The improvement in PFS must be weighed against the morbidity of surgery.

The clinical course of patients with uterine leiomyosarcoma (LMS) is difficult to predict with the currently available categorical staging systems of the American Joint Committee on Cancer (AJCC) and the International Federation of Gynecology and Obstetrics (FIGO). The objective of the current study was to develop and validate a novel, clinically relevant, individualized prognostic model for patients with uterine LMS.

Patients with uterine LMS who presented at the authors' institution from 1982 to 2008 were analyzed. The nomogram model was chosen based on the clinical evidence and statistical significance of the predictors, including age at diagnosis, tumor size, histologic grade, uterine cervix involvement, extrauterine spread, distant metastases, and mitotic index. Five-year overall survival (OS) was the predicted endpoint. The concordance probability (CP) was used as a predictive accuracy measure and compared with the CP of current staging systems. The model was internally validated using 200 bootstrap samples to correct for over fitting.

One hundred eighty-five of 270 patients were eligible for the nomogram analysis. The median follow-up was 5.4 years, and the median OS was 3.75 years (95% confidence interval, 3-6 years). The CP of the newly developed nomogram was 0.67 (95% confidence interval, 0.63-0.72). This was superior to predictions based on AJCC and FIGO staging. The bootstrap-validated CP was 0.65 with good calibration accuracy.

The authors developed and internally validated a uterine LMS-specific nomogram to predict 5-year OS. This novel, individualized prognostic model outperforms traditionally used categorical staging systems and may be useful for patient counseling and for better selection of patients for adjuvant therapy trials.

Uterine leiomyosarcoma (LMS) is staged by the modified International Federation of Gynecology and Obstetrics (FIGO) staging system for uterine cancer. We aimed to determine whether the American Joint Committee on Cancer (AJCC) soft tissue sarcoma (STS) staging system is more accurate in predicting progression-free survival (PFS) and overall survival (OS).

Patients with uterine LMS who presented at our institution from 1982 to 2005 were staged retrospectively according to a modified FIGO staging system and the AJCC STS staging system. The predictive accuracy of the two staging systems was compared using concordance estimation.

Two hundred nineteen patients had sufficient clinical and pathologic information to be staged under both systems; 132 patients were upstaged using the AJCC staging system, whereas only four were downstaged. Stage-specific PFS and OS rates for stages I, II, and III differed substantially between the two staging systems. In both systems, there was prognostic overlap between stages II and III. Thus, despite the marked stage-specific differences in 5-year PFS and OS rates for stages I, II, and III, both systems had similar concordance indices.

Estimates of stage-specific PFS and OS for uterine LMS were altered substantially when using the AJCC versus FIGO staging system. Adjuvant treatment strategies should be tested in patients at substantial risk for disease progression and death. Neither the FIGO nor AJCC staging system is ideal for identifying such patients, suggesting a need for a uterine LMS-specific staging system to better target patients for trials of adjuvant therapies.