Adult Renal Sarcoma: Clinical Features and Survival in a Series of Patients Treated at a High-volume Institution

Epidemiology, treatment and outcomes of primary renal sarcomas in adult patients

To assess epidemiology, clinical presentation, treatment and overall survival of adult patients with renal sarcomas, the 2004-2016 SEER and NCDB databases were queried for adult patients diagnosed with renal sarcoma, calculating average annual age-adjusted incidence rates (AAIR) and average annual percentage change (AAPC) as well as overall survival (OS). In n = 1279 included renal sarcoma patients, AAIR remained constant over the study period (average 0.53 cases/1million; AAPC = 0.7, p = 0.6). Leiomyosarcoma (AAIR 0.14 cases/1 million) and malignant rhabdoid tumors (0.06 cases/1 million) were most common. Sarcoma histiotypes demonstrated considerable heterogeneity regarding demographic and cancer-related variables. Patients presented with advanced local extent (T3 33.3%; T4 14.2%) or distant metastases (29.1%) and commonly underwent surgical resection (81.6%). Longer OS was independently associated with younger age, female sex, lower comorbidity index, low T stage, negative surgical margins, absence of tumor necrosis or distant metastases and leiomyosarcoma histiotype (multivariable p < 0.05 each). Treatment efficacy varied according to sarcoma histiotype (interaction p < 0.001). Accounting for 0.25% of renal malignancies, renal sarcomas include 43 histiotypes with distinct epidemiology, clinical presentation, outcomes and sensitivity to systemic therapy, thereby reflecting soft-tissue sarcoma behavior. Renal sarcoma treatment patterns follow recommendations by renal cancer guidelines with surgical resection as the cornerstone of therapy.

Soft-Tissue Sarcomas of the Genitourinary Tract with Radiologic-Pathologic Correlation

Genitourinary tract soft-tissue sarcomas are rare neoplasms with varied pathologic and clinical features. While some of these tumors may be aggressive high-grade malignancies, others are low grade with a relatively better prognosis. Given that the grade and extent of the disease are important prognostic factors in these tumors, timely diagnosis is crucial. Unfortunately, most imaging features of these malignancies are not pathognomonic, and various histologic subtypes do not manifest with typical classic imaging features. Therefore, reliable differentiation of the various histologic tumor types is not always possible based solely on the radiologic manifestations. Imaging findings need to be considered in the context of clinical history in corroboration with radiologic-pathologic correlation. The authors discuss the specific imaging and pathologic characteristics of various genitourinary tract soft-tissue sarcomas, emphasizing diagnostic difficulties and differential diagnoses. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Renal Sarcoma: A Population-Based Study

INTRODUCTION

Renal sarcomas are exceedingly rare and lack a prognostic stage classification. We thus aimed to investigate the contemporary clinicopathologic characteristics and outcomes of renal sarcomas at a national level.

PATIENTS AND METHODS

We utilized the Surveillance, Epidemiology, and End Results database to extract data on patients with renal sarcoma diagnosed between 2004 and 2015. We estimated median, 1-, 3-, and 5-year overall survival (OS) probabilities via Kaplan-Meier curves and used multivariable regression to compare OS between different patient groups.

RESULTS

We identified 365 patients; at diagnosis, 104 patients (28.5%) had stage I disease (T1N0M0), 133 patients (36.4%) patients had stage II disease (T2-4N0M0), and 117 patients (32.1%) patients had stage III disease (any T, N1, or M1). Median survival was 105 months (interquartile range [IQR], 29 - not reached) for stage I disease, 46 months (IQR 14-118 months) for stage II disease, 8 months (IQR 3-28 months) for stage III disease, and 32 months (IQR, 8-116 months) for the entire cohort. Patient age (hazard ratio [HR] for death [per year] 1.02, 95% confidence interval [95% CI] 1.00-1.04), stage (II vs. I: HR 1.71, 95% CI 1.00-2.92; III vs. I: HR 4.93, 95% CI 2.68-9.05), grade (grade 3 vs. grade 1: 3.07, 95% CI 1.18-8.00; grade 4 vs. grade 1: HR 3.66, 95% CI 1.41-9.49), and possessing medical insurance (HR 0.40, 95% CI 0.16-0.94) were independently and significantly associated with OS. Performance of nephrectomy also trended towards independently improving OS (HR 0.23, 95% CI 0.05-1.09).

CONCLUSION

A novel staging classification for renal sarcomas into a 3-stage system based on Tumor Node Metastasis (TNM) criteria produces distinct survival curves, although further studies are needed to robustly assess its validity.

Development and validation of a prognostic nomogram for adult patients with renal sarcoma: A retrospective study based on the SEER database

Background

Renal sarcoma (RS) is rarely seen in clinical practice. The purpose of this study was to develop a prognostic nomogram model, which could predict the probability of overall survival (OS) and cancer-specific survival (CSS) in adult patients with RS.

Methods

Patients diagnosed with RS were recruited from the SEER database between 2004 and 2015, and randomized to two cohorts: the training cohort and the validation cohort. Uni- and multivariate Cox regression analyses in the training cohort were used to screen independent prognostic factors for OS and CSS. Prognostic nomograms for OS and CSS were created separately for adult RS patients based on independent risk factors. The area under the receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA) were used to validate the nomograms.

Results

A total of 232 eligible patients were recruited, including 162 in the training cohort and 70 in the validation cohort. Sex, histological type, SEER stage, and surgery were independent prognostic factors for OS, while histological type, SEER stage, surgery, chemotherapy were independent prognostic factors for CSS. Based on the above independent prognostic factors, prognostic nomograms for OS and CSS were created respectively. In the training cohort, the AUCs of the nomograms for OS and CSS were 0.742 and 0.733, respectively. In the validation cohort, the AUCs of the nomograms for OS and CSS were 0.837 and 0.758, respectively. The calibration curves of the nomograms showed high consistencies between the predicted and actual survival rates. Finally, the DCA demonstrated that the nomograms in the wide high-risk threshold had a higher net benefit than the SEER stage.

Conclusion

A prognostic nomogram for renal sarcoma was created and validated for reliability and usefulness in our study, which assisted urologists in accurately assessing the prognosis of adult RS patients.

Primary renal sarcomas: imaging features and discrimination from non-sarcoma renal tumors

OBJECTIVES

To assess imaging features of primary renal sarcomas in order to better discriminate them from non-sarcoma renal tumors.

METHODS

Adult patients diagnosed with renal sarcomas from 1995 to 2018 were included from 11 European tertiary referral centers (Germany, Belgium, Turkey). Renal sarcomas were 1:4 compared to patients with non-sarcoma renal tumors. CT/MRI findings were assessed using 21 predefined imaging features. A random forest model was trained to predict "renal sarcoma vs. non-sarcoma renal tumors" based on demographics and imaging features.

RESULTS

n = 34 renal sarcomas were included and compared to n = 136 non-sarcoma renal tumors. Renal sarcomas manifested in younger patients (median 55 vs. 67 years, p < 0.01) and were more complex (high RENAL score complexity 79.4% vs. 25.7%, p < 0.01). Renal sarcomas were larger (median diameter 108 vs. 43 mm, p < 0.01) with irregular shape and ill-defined margins, and more frequently demonstrated invasion of the renal vein or inferior vena cava, tumor necrosis, direct invasion of adjacent organs, and contact to renal artery or vein, compared to non-sarcoma renal tumors (p < 0.05, each). The random forest algorithm yielded a median AUC = 93.8% to predict renal sarcoma histology, with sensitivity, specificity, and positive predictive value of 90.4%, 76.5%, and 93.9%, respectively. Tumor diameter and RENAL score were the most relevant imaging features for renal sarcoma identification.

CONCLUSION

Renal sarcomas are rare tumors commonly manifesting as large masses in young patients. A random forest model using demographics and imaging features shows good diagnostic accuracy for discrimination of renal sarcomas from non-sarcoma renal tumors, which might aid in clinical decision-making.

KEY POINTS

• Renal sarcomas commonly manifest in younger patients as large, complex renal masses. • Compared to non-sarcoma renal tumors, renal sarcomas more frequently demonstrated invasion of the renal vein or inferior vena cava, tumor necrosis, direct invasion of adjacent organs, and contact to renal artery or vein. • Using demographics and standardized imaging features, a random forest showed excellent diagnostic performance for discrimination of sarcoma vs. non-sarcoma renal tumors (AUC = 93.8%, sensitivity = 90.4%, specificity = 76.5%, and PPV = 93.9%).

Renal liposarcoma: case report and review of systemic treatment

Liposarcomas are malignant mesenchymal tumours usually located in the retroperitoneum, rarely occurring as a single lesion in the kidney. We present a case of a 59-year-old male patient with a left renal mass detected by computed tomography scan. He underwent radical nephrectomy and the histopathological study reported a primary undifferentiated liposarcoma of the kidney without nodal involvement. After 15 months of surgery, he remained asymptomatic and without evidence of disease recurrence. The objective of this report is to present a case and literature review with current evidence of treatment options and prognostic factors for survival.

Adult genitourinary sarcoma: The era of optional chemotherapeutic agents for soft tissue sarcoma

OBJECTIVE

To report our institutional experience with treatment of primary genitourinary soft tissue sarcoma.

METHODS

We retrospectively reviewed the medical records of adult soft tissue sarcoma patients treated between March 2005 and May 2019. The primary tumor sites included the prostate, kidney, urinary bladder and the paratesticular structures.

RESULTS

A total of 19 patients - 16 men (84%) and three women (16%) - were enrolled in the study. The median age was 41 years (range 20-79 years). The most common primary site was the prostate (in eight patients; 42%), and prostatic sarcoma patients were younger than patients with sarcomas of other origins. The most common histological subtype was leiomyosarcoma (in five patients; 26%). The overall survival rates after 1, 3 and 5 years were 61.5%, 34.4% and 25.8%, respectively. The median survival time was 20.7 months (95% confidence interval 5.9-35.5 months). Univariate analysis showed that an absence of metastasis at diagnosis and complete surgical resection were predictive of favorable survival. In the chemotherapy group, the objective response rate was 20.5%. Pazopanib was administered to nine patients in the late-line setting, and the objective response rate was 11.1%; six grade ≥3 adverse events were observed in three patients.

CONCLUSIONS

Inoperable metastatic genitourinary soft tissue sarcoma remains difficult to treat, as previously reported. Further investigation on this malignancy, including optimization of currently available antitumor drugs and the development of novel therapeutic agents, is required.

Malignant pulmonary embolism associated with renal sarcoma: A case report

RATIONALE

The preoperative diagnosis of massive pulmonary tumor embolism associated with renal neoplasms is relatively rare. In most cases, pulmonary tumor embolism is detected intraoperatively during renal tumor resection. Moreover, primary renal sarcoma is rare, and primary renal sarcoma complicated by pulmonary tumor embolism is extremely rare; accordingly, there is no optimal treatment for such cases. Herein, we report a case of renal sarcoma associated with pulmonary tumor embolism.

PATIENT CONCERNS

A 39-year-old man was admitted to the emergency room owing to the sudden onset of dyspnea and palpitation.

DIAGNOSIS

Contrast-enhanced computed tomography (CT) revealed a large mass in the right kidney involving the infrahepatic inferior vena cava, with massive pulmonary emboli in both the pulmonary arteries.

INTERVENTIONS

Emergency pulmonary embolectomy with radical nephrectomy was performed.

OUTCOMES

The patient experienced apparent remission of dyspnea, and resolution of right ventricle dysfunction. However, although remnant emboli were detected in the segmental arteries on postoperative CT, complete resolution of pulmonary embolism was observed after adjuvant chemotherapy.

LESSONS

Thus, concomitant cytoreductive nephrectomy with pulmonary embolectomy along with chemotherapy may be effective for patients with renal sarcoma with pulmonary tumor embolism.

Case Report: Partial nephrectomy in primary renal sarcoma presenting as Wunderlich syndrome; a rare tumour with rare presentation managed atypically

Spontaneous retroperitoneal haemorrhage also called Wunderlich Syndrome (WS) may be caused by various aetiologies. One of the most common causes is renal tumour. Renal sarcoma is a rare cause of WS, and renal sarcoma in itself is a rare entity. In the era of nephron-sparing surgery, optimum management of primary renal sarcoma remains a dilemma as there are limited number of cases available in the literature. Nevertheless, radical nephrectomy remains the recommended treatment, keeping in mind the aggressiveness of the tumour. We report a case of primary undifferentiated renal sarcoma, which presented as WS, and which was managed by partial nephrectomy.

Comprehensive Genomic Profiling of Adult Renal Sarcomas Provides Insight into Disease Biology and Opportunities for Targeted Therapies

BACKGROUND

Primary adult renal sarcomas (RSs) are rare aggressive neoplasms. Clinical outcomes are extremely poor, and optimal treatment remains challenging.

OBJECTIVE

To identify genomic alterations (GAs) in patients with RSs.

DESIGN, SETTING, AND PARTICIPANTS

Comprehensive genomic profiling (CGP) was conducted on DNA/RNA extracted from formalin-fixed paraffin-embedded tissue using the FoundationOne Heme/Sarcoma assay in 13 adult, locally advanced or metastatic RSs of various histologic types.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

All classes of GAs, including base substitutions, small indels, rearrangements, copy number alterations, tumor mutational burden (TMB), and microsatellite instability (MSI), were analyzed.

RESULTS AND LIMITATIONS

CGP revealed 55 GAs (4.2 per tumor), 29 of which were clinically relevant genomic alterations (CRGAs; 2.2 per tumor). At least one CRGA was detected in nine (69%) cases. High-level amplifications (more than six copies) involving 4q12 amplicon of the KIT and PDGFRA genes were identified in four (31%) cases (two undifferentiated pleomorphic sarcomas [UPSs], one sarcomatoid renal cell carcinoma, and one myxofibrosarcoma). Both UPSs also had KDR gene amplification in addition to KIT and PDGFRA. Additional CRGAs were found in CDKN2A/B (23%), NF1 (23%), and MET (8%). All RSs were MSI stable, the mean TMB was 3.5 mutations/megabase (Mb), and none (0%) featured TMB >10 mutations/Mb. Limitations include the small sample size.

CONCLUSIONS

RSs are characterized by diverse histology and genomic profiles including 31% of cases with 4q12 amplification harboring the KIT/PDGFRA/KDR genes. Of the tumors, 69% carry CRGAs, which could lead to potential benefit from targeted therapies; however, a low TMB also suggests that these cases are unlikely to respond to checkpoint inhibitors.

PATIENT SUMMARY

This study provides insights into molecular biology of renal sarcoma, a rare aggressive subtype of kidney tumors. We demonstrated that renal sarcomas harbor unique, recurrent, clinically relevant molecular abnormalities that provide new opportunities for targeted therapies.

Adult renal sarcoma: A rare case of recurrence 13 years after initial resection

Renal sarcoma is a rare and aggressive malignancy without proper guidelines for treatment. Due to the aggressiveness of this disease and the potential for recurrence, we believe that extensive surgical resection with healthy margins may be the best option to treat this condition during both initial resection and resection of the recurrent lesion. Clinical follow-up is also important to monitor for tumor recurrence.

Renal capsule metastasis from renal pelvic cancer: a case report

Background

Metastatic renal cancers are relatively common. Most are metastases to the renal parenchyma via a hematogenous route and are derived from lung, breast, and gastrointestinal cancer, malignant melanoma, and hematologic malignant cancer. However, little is known about renal capsule metastasis from other cancers.

Case presentation

We report a 71-year-old woman with breast cancer who was treated with endocrine therapy. She presented with gross hematuria and was diagnosed as having right renal pelvic cancer and renal cell cancer. She underwent right laparoscopic radical nephroureterectomy. Pathological findings revealed right pelvic cancer and renal capsule metastasis.

Conclusion

Renal capsule metastasis derived from renal pelvic cancer is very rare. When diagnosing renal capsule cancer, we believe that renal capsule metastasis should also be taken into consideration. Clinical and radiological differential diagnosis of renal capsule metastasis from renal cell cancer and primary renal capsule cancer is difficult. Assessment of the histopathological findings of the surgical specimens seems to be the only realistic approach to achieving the correct diagnosis.

Sarcomatoid Variant of Urothelial Carcinoma of the Renal Pelvis with Inferior Vena Cava Tumour Thrombus: A Case Report and Literature Review

Sarcomatoid variant of urothelial carcinoma (SVUC) of the renal pelvis is a rare entity. To the best of our knowledge, around 25 cases of this neoplasm have been reported in the literature to date, most of which were of high stage. The inferior vena cava tumour thrombus, which is a hallmark of renal cell carcinoma (RCC), may rarely be found in urothelial carcinoma of renal pelvis. In this report, a case of SVUC associated with tumour extension to inferior vena cava is documented. This association has been encountered in only one previously reported case. The possibility of urothelial carcinoma of the renal pelvis should therefore be included in the differential diagnosis of tumour thrombus of the inferior vena cava.

Adult genitourinary sarcoma: Clinical characteristics and survival in a series of patients treated at a high-volume institution

OBJECTIVES

To report our institutional experience in the management of adult genitourinary sarcoma.

METHODS

This was a retrospective analysis of data on adult genitourinary sarcoma treated at the West China Hospital, Sichuan University, Chengdu, Sichuan, China from 1985 to 2010. Clinicopathological parameters were analyzed to determine their impact on overall, recurrence-free and metastasis-free survivals.

RESULTS

A total of 46 women and 142 men were included, with a median age of 42 years. Of these, 152 cases were high-grade. The most common site was the paratesticular region. Surgical resection was carried out in 155 patients (82.4%), with negative margin in 106. After a minimum follow up of 5 years, 20 patients (11.6%) survived disease-free, 14 (8.1%) were alive with disease and 138 (80.2%) died of disease. Survival rates at 1, 3 and 5 years were 91.3%, 64.0% and 47.7%. In univariate analyses, liposarcoma, high grade, metastasis at diagnosis, a lack of surgical resection and positive margin were predictive of unfavorable survival. In multivariate analyses, high grade, a lack of surgical resection and chemotherapy were independent predictors of poor survival.

CONCLUSIONS

Adult genitourinary sarcoma is an aggressive malignancy, usually presenting at advanced stage, with a high incidence of recurrence and metastasis. Complete resection and selective combination of chemotherapy and radiotherapy might constitute the optimal treatment for this disease.

Clinicopathologic characteristics and survival for adult renal sarcoma: A population-based study

INTRODUCTION

To analyze the association of clinicopathologic characteristics and treatment modality with survival among adult patients with renal sarcoma.

METHODS

We identified 489 adults diagnosed with renal sarcoma from the Surveillance, Epidemiology and End Results registry between 1973 and 2011. Cancer-specific survival was estimated using the Kaplan-Meier method and was compared between groups with log rank and Cox models.

RESULTS

Median age at diagnosis was 61 years, while median tumor size was 11 cm. Tumor histology was leiomyosarcoma in 175, liposarcoma in 100, other subtypes in 129, and unknown in 85 cases. Tumor stage at diagnosis was nonmetastatic in 322 (67%) and metastatic in 167 (33%) cases. Treatment of nonmetastatic disease was surgical resection in 171 patients, radiation in 24, both in 35, neither in 18, and unknown in 74 cases. Treatment of metastatic disease was surgery in 39 patients, radiation in 27, both in 11, neither in 42, and unknown in 48. For nonmetastatic and metastatic disease, 5-year cancer-specific survival rates were 58% and 16%, respectively. On multivariable analysis, surgery was associated with decreased cancer-specific mortality among both patients with nonmetastatic disease (hazard ratio = 0.34; 95% CI: 0.14-0.85) and those with metastatic disease (hazard ratio = 0.38; 95% CI: 0.18-0.77). Age, race, tumor size, and tumor grade were independently associated with cancer death in nonmetastatic disease, whereas race and tumor histology remained associated with mortality in metastatic disease (all P < 0.05).

CONCLUSION

Although metastatic renal sarcoma has an ominous prognosis, durable survival may be achieved for localized tumors. Although we recognize the potential for selection bias, our results suggest an association between surgical resection and decreased mortality for both nonmetastatic and metastatic renal sarcoma.

Adult Urological Soft Tissue Sarcomas: A Multicenter Study of the Anatolian Society of Medical Oncology (ASMO)

OBJECTIVE

To analyze clinicopathological characteristics, prognostic factors and survival rates of the patients with urological soft tissue sarcomas treated and followed up in Turkey.

MATERIALS AND METHODS

For overall survival analyses the Kaplan-Meier method was used. From medical records, nine prognostic factors on overall survival were analysed.

RESULTS

For the 53 patients (34 males, 19 females) whose charts were reviewed, the median age was 53 (range 22 to 83) years. Most frequently renal location (n=30; 56.6%) was evident and leiomyosarcoma (n=20, 37.7%) was the most frequently encountered histological type. Median survival time of all patients was 40.3 (95% CI, 14.2-66.3) months. In univariate analysis, male gender, advanced age (≥50 years), metastatic stage, unresectability, grade 3, renal location were determined as worse prognostic factors. In multivariate analysis, metastatic stage, unresectability and grade 3 were determined as indicators of worse prognosis.

CONCLUSIONS

Urological soft tissue sarcomas are rarely seen tumours in adults. The most important factors in survival are surgical resection, stage of the tumour at onset, grade and location of the tumour, gender and age of the patients.

Twenty-five cases of adult prostate sarcoma treated at a high-volume institution from 1989 to 2009

OBJECTIVE

To analyze the clinical characteristics, treatment modalities, and outcomes of adult prostate sarcoma treated at our institution.

MATERIALS AND METHODS

The medical records of 25 adult patients with prostate sarcoma were obtained from January 1989 to December 2009. The clinicopathologic parameters were evaluated to determine their effect on survival.

RESULTS

The median age was 37 years (range 18-81). The median tumor size was 9.5 cm (range 4-25). The median serum prostate-specific antigen level was 1.39 ng/mL (range 0.39-33.20). The most common symptom was dysuria (72%). Transrectal ultrasound-guided needle biopsy was used to diagnose 22 sarcomas, transurethral resection of the prostate to diagnose 2, and open surgery to diagnose 1. The predominant histologic subtype was leiomyosarcoma (40%); 21 (88%) were high grade and 6 patients had metastatic disease. Surgical resection of curative intent was performed in 14 patients, with negative margins in 10. After a median follow-up of 21 months (range 5-63), 2 patients were disease free, 4 were alive with disease, and 19 had died of their disease. Overall, the 1-, 2-, 3-, and 5-year survival rate was 80.0%, 47.4%, 22.6%, and 11.3%, respectively, and the median survival time was 23 months. The median survival time after recurrence was 20 months (range 9-39) and that after metastasis was 10 months (range 3-23). Age >50 years, metastasis at presentation, and a lack of surgery with curative intent were independently predictive of an unfavorable outcome.

CONCLUSION

Adult prostate sarcoma accounted for 0.7% of primary prostate malignancies and carried a poor prognosis. Early diagnosis and surgical resection with curative intent offer patients the best chance of survival.

Sarcomas of abdominal organs: computed tomography and magnetic resonance imaging findings

Sarcomas originating from abdominal organs are extremely rare, and literature in which investigators focus on their imaging features is scarce. This article aims to review the computed tomography and magnetic resonance imaging features of these rare tumors and to help in clinical diagnosis. Various sarcomas (eg, angiosarcoma, undifferentiated embryonal sarcoma, leiomyosarcoma, carcinosarcoma, rhabdomyosarcoma) originating, respectively, from different abdominal visceral organs (liver, pancreas, spleen, kidney, adrenal gland, uterus, and prostate gland) are reviewed along with cases we encountered.

Adult urologic sarcoma: experience during 2 decades

OBJECTIVE

To identify factors associated with long-term outcome and to report possibly meaningful clinical features in a unicentric sample of adult urologic sarcomas.

MATERIALS AND METHODS

Thirty-five patients treated between 1992 and 2011 were studied. Except for 3 patients, surgery was the initial treatment. The median follow-up in the surviving (censored) patients was 11.3 years. Kaplan-Meier method and competing risk analysis were used to evaluate outcome. Disease recurrence, disease-specific mortality, and overall mortality were the study endpoints. Comparisons were made with the log rank and the Pepe-Mori tests. Cox proportional hazard models were used to identify independent predictors of disease recurrence.

RESULTS

Only disease grade was significantly associated with all 3 study endpoints. The primary tumor site was significantly associated with disease-specific and recurrence-free survival but did not reach the significance level concerning overall survival. In the multivariate analysis, primary site and tumor grade were identified as predictors of disease recurrence. Whereas 10-year disease-specific survival was 100% in patients with low grade inguinoscrotal tumors, it was 0% in patients with high grade disease arising from other sites.

CONCLUSIONS

Low grade and inguinoscrotal origin are factors associated with favorable outcome in urologic sarcomas. Repeat interventions to remove or to inactivate recurrent tumors or metastases seem to provide clinical benefit in individual cases.