Treatment and outcomes of clear cell sarcoma of the kidney: A report from the Children's Oncology Group studies AREN0321 and AREN03B2.

BACKGROUND: On the fifth National Wilms Tumor Study, treatment for clear cell sarcoma of the kidney (CCSK) included combined vincristine, doxorubicin, cyclophosphamide, and etoposide (regimen I) plus radiation therapy (RT), yielding 5-year event-free survival (EFS) rates of 100%, 88%, 73%, and 29% for patients who had with stage I, II, III, and IV disease, respectively. In the Children's Oncology Group study AREN0321 of risk-adapted therapy, RT was omitted for stage I disease if lymph nodes were sampled, and carboplatin was added for stage IV disease (regimen UH-1). Patients who had stage II/III disease received regimen I with RT. METHODS: Four-year EFS was analyzed for patients enrolled on AREN0321 and on those enrolled on AREN03B2 who received AREN0321 stage-appropriate chemotherapy. RESULTS: Eighty-two patients with CCSK enrolled on AREN0321, 50 enrolled on AREN03B2 only. The 4-year EFS rate was 82.7% (95% confidence interval [CI], 74.8%-91.4%) for AREN0321 and 89.6% (95% CI, 81.3%-98.7%) for AREN03B2 only (p = .28). When combining studies, the 4-year EFS rates for patients who had stage I (n = 10), II (n = 47), III (n = 65), and IV (n = 10) disease were 90% (95% CI, 73.2%-100.0%), 93.4% (95% CI, 86.4%-100.0%), 82.8% (95% CI, 74.1%-92.6%), and 58.3% (95% CI, 34%-100.0%), respectively. There were no local recurrences among seven patients with stage I disease who were treated without RT. One stage I recurrence occurred in the brain, which was the most common site of relapse overall. Among patients with local stage III tumors, neither initial procedure type, margin status, nor lymph node involvement were prognostic. CONCLUSIONS: Patients with stage I CCSK had excellent outcomes without local recurrences when treated without RT. Patients with stage IV disease appeared to benefit from a carboplatin-containing regimen, although their outcomes remained unsatisfactory. Further research is needed to improve outcomes for patients with advanced-stage disease (ClinicalTrials.gov identifiers NCT00335556 and NCT00898365).

Clear cell sarcoma of the kidney in Austrian children: Long-term survival after relapse.

INTRODUCTION: Clear cell sarcoma of the kidney (CCSK) is a rare malignant childhood renal tumour. Recently, the central nervous system (CNS) was found to be the most frequent site of relapse associated with a poor outcome. Optimal treatment strategies are scarce. PATIENTS AND METHODS: Retrospective data analysis of all Austrian children with CCSK. They were enrolled in the Austrian-Hungarian Wilms Tumour Study (AHWTS) 1989, the SIOP93-01 or the SIOP2001 study between 1990 and 2019. Demographic, diagnostic, treatment-related variables and survival data were analysed. RESULTS: We identified 12 children with CCSK (M = 7, F = 5; median age 1.6 years). All had localised disease (stage I: 2; stage II: 2; stage III: 8) at diagnosis, and a first complete remission (CR1) was achieved in 12/12. Six patients are in an ongoing CR1 (median follow-up 10 years). Six other patients had a relapse (local 1; brain 5) a median time of 2.4 years from diagnosis. Two patients died of the disease 4 months and 2.8 years after first relapse. Four of five patients with CNS relapse are in CR2 with a median follow-up time of 9.3 years after relapse diagnosis. Relapse treatment included a combination of chemotherapy, radiation and surgery. Two children received high-dose chemotherapy followed by autologous stem cell rescue, and one child received intrathecal mafosphamide. Long-term side effects after treatment were impaired tubular renal function (n = 4), cardiomyopathy (n = 1) and growth disorders (n = 1). CONCLUSIONS: In this series, the brain was the most common site of relapse. Long-term survival after recurrence was achievable with intensive multimodal therapy.

Primary Cutaneous Clear Cell Sarcoma, Clinical Outcome With Sentinel Lymph Nodes Status.

OBJECTIVES: Primary cutaneous clear cell sarcoma (PCS) is a rare malignancy and difficult to differentiate from melanoma. We investigated factors influencing survival and recurrence. METHODS: An institutional cancer registry and literature search were used for a retrospective study. Only clear cell sarcoma cases with a primary site of skin and subcutaneous tissue were included. Kaplan-Meier and Cox regression analyses were used to assess survival time and hazard ratios. RESULTS: Three eligible cases were identified at our institution. In addition, the PubMed and Google Scholar reviews identified 1,878 items, with 23 patients with PCS. The median age was 25 years with 62% female. The tumors ranged in size from 0.4 to 4.5 cm. Cytogenetics showed t(12;22)(q13;q12) in all cases and a unique variant of t(2;22)(q32.3;q12) in one case. Surgery was the most common treatment, followed by chemotherapy/radiation. PCS recurred in 46% of patients with a median relapse-free survival time of 15 months. Only two known PCS-related mortalities were recorded, at 38 and 60 months following initial diagnosis. Smaller tumor size and negative sentinel lymph node biopsy (SLNB) status were significantly associated with a better disease-free survival. CONCLUSIONS: Tumor size and SLNB status influence PCS survival and recurrence. More research is needed due to the rarity of this disease.

Prognostic Factors for Survival in Patients with Clear Cell Sarcoma: An Analysis of the Surveillance, Epidemiology, and End Results (SEER) Database.

BACKGROUND Clear cell sarcoma (CCS) of soft tissue, or malignant melanoma of soft parts, is a rare disease. We aimed to identify prognostic factors linked to patient survival in CCS by analyzing demographic and clinical features using the Surveillance, Epidemiology, and End Results (SEER) database. This study aimed to identify prognostic factors associated with CCS that would be of clinical value. MATERIAL AND METHODS We collected data from patients diagnosed with CCS between 1973 and 2009 from the SEER database. The Kaplan-Meier method and Cox regression analysis were performed to identify prognostic factors for patient survival. RESULTS A total of 175 patients with CCS were identified from the SEER database. The 5-year survival rate was 62.9%, and the 10-year survival rate was 51.3%. Patients with CCS with local stage, and with tumor size ≤3 cm were more likely to have good survival rates. CONCLUSIONS The findings from this study showed that the identifiable prognostic factors in patients with CCS were stage and tumor size. Local stage and tumor size ≤3 cm were favorable prognostic factors for patient survival in CCS.

Prognostic analysis of surgically treated clear cell sarcoma: an analysis of a rare tumor from a single center.

BACKGROUND: The objective of this retrospective study was to evaluate the prognostic value of various factors in clear cell sarcoma patients after radical surgery. METHODS: Forty-two clear cell sarcoma patients from August 2006 to March 2018 were included in the study. Curves of disease-free survival and overall survival were calculated using the Kaplan-Meier method, and univariate and multivariate analyses of various prognostic factors were performed using a Cox proportional hazard regression model. Laboratory test of peripheral blood was recorded before surgery. The optimal cutoff value of systemic inflammatory markers was defined by receiver-operating curve analysis. RESULTS: The 5-year DFS and 5-year OS rate were 22% and 46%, respectively. The median DFS and OS times were 12 and 41.5 months, respectively. In univariate analysis, there was a significant association between shorter DFS and tumor size larger than 5 cm (p = 0.0043), positive surgical margin (p = 0.0233), and the neutrophil-to-lymphocyte ratio (NLR) higher than 2.73 (p = 0.0009). Furthermore, we observed a significant association between shorter OS and tumor size larger than 5 cm (p = 0.0075), positive surgical margin (p = 0.0101), NLR higher than 2.73 (p = 0.0126), the platelet-to-lymphocyte ratio (PLR) higher than 103.89 (p = 0.0147) and the lymphocyte-to-monocyte ratio (LMR) lower than 4.2 (p = 0.0445). A multivariate analysis demonstrated that the surgical margin (p = 0.013) and NLR (p = 0.001) were significantly associated with DFS. Tumor size (p = 0.010) and NLR (p = 0.013) were independent prognostic factors for OS. CONCLUSIONS: This study had the second largest sample around the world and preoperative NLR may be a useful prognostic factor in CCS patients after radical surgery.

Impact of cyclophosphamide and etoposide on outcome of clear cell sarcoma of the kidney treated on the National Wilms Tumor Study-5 (NWTS-5).

PURPOSE: To improve the event-free survival (EFS) and overall survival (OS) for patients with clear cell sarcoma of the kidney (CCSK) by incorporating cyclophosphamide and etoposide into treatment on National Wilms Tumor Study (NWTS)-5. PATIENTS AND METHODS: Patients less than 16 years of age with a centrally confirmed pathological diagnosis of CCSK were eligible for treatment on this prospective single-arm study conducted between August 1995 and June 2002. Staging consisted of CT scans of chest, abdomen, pelvis, bone scan, skeletal survey, and CT or MRI of the head. Treatment consisted of vincristine/doxorubicin/cyclophosphamide alternating with cyclophosphamide/etoposide for 24 weeks and radiation to sites of disease. RESULTS: One hundred eight eligible patients were enrolled on study (69% males, 63% Caucasian), with a median age of 22 months. Stage distribution was as follows: stage I, 12; II, 44; III, 45; IV, 7. Median follow-up was 9.7 years. Five-year EFS and OS were 79% (95% CI: 71%-88%) and 90% (95% CI: 84%-96%). Five-year EFS for stage I-IV was 100%, 88%, 73%, and 29%, respectively. Twenty of the 23 disease-related events occurred within three years of initial treatment. The most common site of recurrence was brain (12/23). CONCLUSION: The outcome for patients with CCSK treated on NWTS-5 was similar to NWTS-4 and accomplished over a shorter treatment duration. Stage was highly predictive of outcome. Brain metastases occurred more frequently than on NWTS-4. Regimen I showed more benefit for patients with stage I and II disease as compared with higher stages of disease where new therapies are needed.

Factors Influencing Overall Survival of Children, Adolescents, and Young Adults With High-risk Renal Tumors.

OBJECTIVE: To identify factors impacting overall survival (OS) in children, adolescents, and young adults with high-risk renal tumors (HRRTs). METHODS: The National Cancer Database was queried for patients ≤30 years old diagnosed with anaplastic Wilms tumors (AWT), clear cell sarcoma of the kidney (CCSK), or rhabdoid tumor of the kidney (RTK) between 2004 and 2013. Demographic, clinical, and OS data were abstracted. OS between groups was compared with a Kaplan-Meier curve. Univariate and multivariate survival analyses were performed. RESULTS: A total of 349 patients were identified meeting criteria; 133 (38.1%) AWT, 120 (34.4%) CCSK, and 96 (27.5%) RTK. Patients with RTK were less likely to undergo surgery than those with AWT or CCSK (77.1% vs 94% vs 99%, P < .001) and less likely to receive chemotherapy (84.4% vs 96.2% vs 95%, P = .013) or radiation (52.1% vs 81.2% vs 86.7%, P < .001). Estimated 5-year OS was 76.1% (95% confidence interval [CI] 67.9-84.4) for AWT, 92.7% (95% CI 87.4-97.9) for CCSK, and 33.5% (95% CI 23.1-43.9) for RTK (P < .001). On multivariate analysis, AWT (HR 3.372, P = .032) and RTK histology (HR 12.595, P < .001) were significantly associated with worse OS, while receiving radiation (HR 0.43, P = .006) was associated with improved OS. LN positivity, margin status, and undergoing surgery were not. Analyzing the HRRTs individually, for AWT, undergoing surgery was associated with OS (HR 0.308, P = .031). For RTK, factors associated with OS included undergoing surgery (HR 0.209, P = .007) and radiation (HR 0.411, P = .008). CONCLUSION: Within the HRRTs, RTK is associated with worse outcomes than either AWT or CCSK. Receiving radiation is significantly associated with improved outcomes, and surgery is important for those with AWT and RTK.

The epidemiology and survivorship of clear cell sarcoma: a National Cancer Database (NCDB) review.

PURPOSE: Clear cell sarcoma (CCS) is a rare soft tissue tumor thought to originate from tendons and aponeuroses. This is the largest and most comprehensive study of CCS to the best of our knowledge. In addition, this is the first study to determine the estimated 10-year overall survival, specific treatment modalities including neoadjuvant and adjuvant combinations, and sites of distant metastasis in CCS utilizing a national database. METHODS: The National Cancer Database (NCDB) was used to study 489 patients diagnosed with CCS from 2004 to 2014. Kaplan-Meier methods were used to estimate 5- and 10-year overall survival, and log-rank tests were used to compare survival amongst stage. RESULTS: Median age at diagnosis was 39 years. Males and females were equally affected. Race distribution was 78% Caucasian and 15% Black. Most common primary site was lower limb or hip (53%). Percentage of patients with distant organ metastases was 15%, with lung being the most common site (4%). Median overall survival was 57.2 months. Overall estimated 5- and 10-year survival was approximately 50 and 38%, respectively. Approximate 5-year survival for Stages I-IV was 75, 65, 35, and 15%, respectively. Stages at disease presentation were 34% at Stage I, 13% at Stage II, 16% at Stage III, and 38% at Stage IV. Surgery was the most common form of treatment (83%); 34% received radiation and 20% received chemotherapy. CONCLUSION: The 5-year overall survival for CCS in Stages III and IV was much worse than Stages I and II. Overall estimated 5- and 10-year survival was approximately 50 and 38%, respectively. Men and women were equally affected and had a median age at diagnosis of 39 years. The most common tumor location was lower limb and hip and the most common site of metastases was the lung.

Clear cell sarcoma of the kidney: patients' characteristics and improved outcome in developing countries.

BACKGROUND: Clear cell sarcoma of the kidney (CCSK) is a rare and aggressive tumor accounting for 5% of pediatric renal tumors with an incidence of 20 patients per year in the USA. It is bone metastasizing with poor prognosis. Our aim was to show characteristics of patients in relation to improved outcome in one of the developing countries. PROCEDURE: We included all patients diagnosed as CCSK in the period between July 2007 and March 2012 at Children's Cancer Hospital, Egypt. Patients' demographics, clinical presentation, pathology, and management were reviewed. Follow up was continued until April 2013. RESULTS: Twenty-five patients were identified in the defined time interval, accounting for 7% all renal tumors diagnosed at the hospital. Mean age was 36 months. Abdominal swelling and hematuria were the most common presentations. Stages I, II, III, IV, and V represented 9 (36%), 3 (12%), 8 (32%), 3 (12%), and 2 (8%), respectively. Twenty-four patients had radical nephrectomy either upfront or after neo-adjuvant chemotherapy. Surgery was followed by adjuvant chemotherapy. Abdominal radiotherapy was given for local stages II and III. Twenty-two patients reached complete remission, while one patient had stationary disease and two patients died due to progression and relapse. Overall survival was 88.5% and event-free survival was 87.8% at 45 months. CONCLUSION: Although previous studies indicate poor prognosis of CCSK, our experience shows that those patients can be treated using extensive chemotherapy combined with proper local control.

Prognostic factors associated with clear cell sarcoma in 14 Chinese patients.

PURPOSE. To identify prognostic factors associated with clear cell sarcomas in 14 Chinese patients. METHODS. Medical records of 7 men and 7 women (mean age, 36 years) with histologically confirmed clear cell sarcoma of tendons and aponeuroses were reviewed. Patient demographics, tumour characteristics, and treatment modalities were retrieved. Prognostic factors associated with favourable 5-year survival were determined. RESULTS. The most affected sites were the thigh (n=5) and the foot (n=4); the mean time from symptom onset to diagnosis was 9.5 months. The tumour stage at diagnosis was IIA in 8 patients, IIB in 2, and III in 4. The mean tumour size was 4.5 cm in diameter. One patient was lost to follow-up. For the remaining 13 patients, the mean time to disease-related mortality was 2.5 years. Nine patients had distant metastases; the most common sites were lungs and pleura (n=7), followed by distant lymph nodes (n=4), bone (n=2), pericardium (n=2), and brain (n=1). All patients underwent surgical excision. Three women and one man (mean age, 27 years) attained 5-year disease-free survival. All had stage IIA tumours at diagnosis. Their mean tumour size was 1.75 cm in diameter, which was significantly smaller than that of all patients (4.5 cm). Tumour size of ≤ 2.5 cm in diameter (p=0.004) and stage IIA tumour at diagnosis (p=0.04) were significant prognostic factors for 5-year survival. CONCLUSION. Tumour size of ≤ 2.5 cm and early stage tumour are associated with 5-year disease-free survival. Early detection is crucial for the prognosis of clear cell sarcomas.

A 20-year prospective study of Wilms tumor and other kidney tumors: a report from Hong Kong pediatric hematology and oncology study group.

BACKGROUND: Renal tumors are one of the most common tumors in children. We aim at evaluating the characteristics and the outcome of Wilms tumor and other malignant kidney tumors in Hong Kong. PROCEDURE: Between January 1990 to December 2010, 68 patients under the age of 18 with malignant renal tumors were diagnosed and received treatment in Hong Kong. Clinical records were updated regularly. Prognostic factors and survival rate were evaluated. RESULTS: Fifty-four patients were diagnosed with Wilms tumor. The annual incidence was estimated to be 2.29 per million. The mean age was 38 months. Median follow-up was 9.2 years. The event-free survival and overall survival rate at 10 years were 85.2% and 92.6%, respectively. A pair of siblings with familial extrarenal Wilms tumor was included. Pulmonary metastasis did exhibit a significant difference in survival rate. Eight cases of clear cell sarcoma of the kidneys were reported and the survival rate was 100%. CONCLUSIONS: The clinical characteristics and outcome of the patients diagnosed Wilms tumor were comparable with other developed countries. Relatively high proportion and excellent outcome were found in clear cell sarcoma of the kidneys.

Clear cell sarcoma of soft tissue: a retrospective review and analysis of 31 cases treated at Istituto Ortopedico Rizzoli.

INTRODUCTION: Clear cell sarcoma (CCS) of soft tissue is a rare melanocytic soft tissue sarcoma with different cytogenetic and natural history than that of melanoma. Objective of this study was to determine outcome predictors in patients treated in our Institute. This objective included the effectiveness of surgical intervention and disease progression after surgery. MATERIALS AND METHODS: Thirty-one patients were diagnosed at our institute with clear cell sarcoma through tissue pathology and immunohistochemistry. Patients received multimodality treatment (surgery, radiotherapy and chemotherapy). Five-year survival rates and prognostic predictors were determined. RESULTS: Sixteen patients were males and 15 females with a median age of 37 years (8-72-years). Twenty-eight tumors were located in extremities and 3 in the trunk area. Eight patients had metastases at their first presentation (6 local lymph nodes and 2 pulmonary metastases). Five and ten-year disease-specific survival rates were 56% and 41%. Two-year disease-specific survival rates for lymph node and pulmonary metastasis groups were 40% and 0%. All metastatic patients died within 5 years follow-up. Five and ten-year disease-specific survival rates for localized tumor cases were 72% and 53%. Male gender, less than 30-years of age, trunk tumor location and size greater than 5 cm were poor prognostic factors according to univariate analysis. Tumor location in the trunk was the only negative prognostic determinant in multivariate model. CONCLUSIONS: Although surgical treatment may be beneficial for tumors without systemic involvement, new chemotherapeutic agents and molecular targeted therapy should be implemented to improve the oncologic outcome in both early and late stage disease.

Malignant renal tumors in childhood: report of 54 cases treated at a single institution.

BACKGROUND: Wilms tumor is the most common primary renal malignancy occurring in childhood. Significant improvement has been made in the treatment of children with Wilms tumor. However, the treatment of patients with non-Wilms renal tumors remains challenging. METHODS: Between 1991 and 2010, 70 children with renal tumors were diagnosed at a single institution. Fifty-four patients were histologically confirmed and divided into three groups, including 42 Wilms tumors, seven clear cell sarcomas of kidney, and five malignant rhabdoid tumors. Most patients underwent unilateral nephrectomy and lymph node sampling followed by adjuvant chemotherapy. Twenty-one of these patients subsequently received radiotherapy. RESULTS: During follow-up, 12 patients died of progressive disease and one died of operative mortality. One patient with unilateral pleural metastases subsequently underwent hematopoietic stem cell transplantation. The median survival time of all patients was 88 months. Children under 2 years of age at diagnosis with Wilms tumor or clear cell sarcoma of kidney had an excellent survival rate of 100% compared to the 0% survival rate of MRT. CONCLUSION: Younger age at diagnosis bore a better prognosis than did older age, whereas a diagnosis of malignant rhabdoid tumor portended a worse prognosis. Younger patients and appropriate treatment may have contributed to the improved prognosis of clear cell sarcoma of kidney.

Clear cell sarcomas of the kidney registered on International Society of Pediatric Oncology (SIOP) 93-01 and SIOP 2001 protocols: a report of the SIOP Renal Tumour Study Group.

PURPOSE: Clear Cell Sarcoma of the Kidney (CCSK) is a rare childhood renal tumour. Only a few homogeneously treated CCSK cohorts have been reported. This study aims to describe clinical characteristics and survival of CCSK patients treated according to recent International Society of Pediatric Oncology (SIOP) protocols. PATIENTS AND METHODS: We analysed the prospectively collected data of patients with a histologically verified CCSK, entered onto SIOP 93-01/2001 trials. RESULTS: A total of 191 CCSK patients (64% male) were analysed, with a median age at diagnosis of 2.6 years. Stage distribution for stages I, II, III and IV was 42%, 23%, 28% and 7%, respectively. Pre-operative chemotherapy was administered to 169/191 patients. All patients underwent total nephrectomy and 189/191 patients received post-operative chemotherapy. Radiotherapy was applied in 2/80 stage I, 33/44 stage II, 44/54 stage III and 6/13 stage IV patients. Five year event-free survival (EFS) and overall survival (OS) were 79% (95% confidence interval (CI): 73-85%) and 86% (95% CI: 80-92%) respectively. Stage IV disease and young age were significant adverse prognostic factors for event-free survival. Factors such as gender, tumour volume and type of initial treatment were not found to be prognostic for EFS and OS. CONCLUSION: In this largest SIOP cohort described so far, overall outcome of CCSK is reasonable, although treatment of young and advanced-stage disease patients is challenging. As further intensification of treatment is hampered by direct and late toxicity, future directions should include the development of targeted therapy based on specific molecular aberrations of CCSK.

Sentinel node biopsy in soft tissue sarcoma subtypes with a high propensity for regional lymphatic spread--results of a large prospective trial.

BACKGROUND: The role of sentinel lymph node biopsy (SLNB) in soft tissue sarcoma patients has yet to be determined. We sought to evaluate the role of SLNB in the treatment of patients with clear cell sarcoma (CCS), synovial sarcoma (SS), epithelioid sarcoma (ES) and rhabdomyosarcoma (RMS). PATIENTS AND METHODS: Sixty-two consecutive patients without history of regional lymphatic spread or evidence of distant metastases underwent SLNB. RESULTS: Positive sentinel nodes were identified in 2 out of 42 patients with SS and in 6 out of 12 patients with CCS. Only two CCS patients had further metastatic nodes in regional dissection. Both of these patients, along with another CCS patient, developed distant metastases and ultimately died of disease. The remaining three CCS patients are disease-free in follow-up. One patient with SS and another with ES developed regional lymph node metastases following a negative SLNB, while a further patient with RMS developed distant metastases followed by a local recurrence with regional metastases shortly after. CONCLUSIONS: SLNB is an important diagnostic tool for patients with CCS, who appear to have a high rate of clinically occult regional lymph node metastases at diagnosis. For SS patients, SLNB appears to be of very little relevance.

Outcomes of patients with revised stage I clear cell sarcoma of kidney treated in National Wilms Tumor Studies 1-5.

PURPOSE: To report the clinical outcomes of children with revised stage I clear cell sarcoma of the kidney (CCSK) using the National Wilms Tumor Study Group (NWTS)-5 staging criteria after multimodality treatment on NWTS 1-5 protocols. METHODS AND MATERIALS: All CCSK patients enrolled in the National Wilms Tumor Study Group protocols had their pathology slides reviewed, and only those determined to have revised stage I tumors according to the NWTS-5 staging criteria were included in the present analysis. All patients were treated with multimodality therapy according to the NWTS 1-5 protocols. RESULTS: A total of 53 children were identified as having stage I CCSK. All patients underwent primary surgery with radical nephrectomy. The chemotherapy regimens used were as follows: regimen A, C, F, or EE in 4 children (8%); regimen DD or DD4A in 33 children (62%); regimen J in 4 children (8%); and regimen I in 12 children (22%). Forty-six patients (87%) received flank radiation therapy (RT). Seven children (13%) did not receive flank RT. The median delay between surgery and the initiation of RT was 9 days (range, 3-61). The median RT dose was 10.8 Gy (range, 10-36). The flank RT doses were as follows: 10.5 or 10.8 Gy in 25 patients (47%), 11-19.9 Gy in 2 patients (4%), 20-29.9 Gy in 9 patients (17%), and 30-40 Gy in 10 patients (19%). The median follow-up for the entire group was 17 years (range, 2-36). The relapse-free and cancer-specific survival rate was 100% at the last follow-up examination. CONCLUSIONS: The present results have demonstrated that children with revised stage I CCSK using the NWTS-5 staging criteria have excellent survival rates despite the use of varying RT doses and chemotherapy regimens in the NWTS 1-5 protocols.

Clear cell sarcoma of the kidney: a review.

Clear cell sarcoma of the kidney (CCSK) is a rare renal tumour that is observed most often in children under 3years of age. Only a few large series of CCSK have been reported and patients with CCSK are often included among patients with other types of childhood renal tumours. The purpose of this paper is to review the published series and case reports of CCSK and to create an up-to-date overview of clinical and histological features, genetics, treatment, and outcome.

Clear-cell sarcoma of the soft tissue--a rare diagnosis with a fatal outcome.

Clear-cell sarcomas account for less than 1% of all soft tissue tumours. They most often occur in middle-aged adults as a deeply located lesion with predilection to the tendons and aponeuroses. The aim of the present study was to show possible influencing factors on the outcome after surgical treatment in a detailed case series. We reviewed the medical records of 11 patients with the diagnosis of a clear-cell sarcoma of the soft tissue. These cases were analysed with regard to age, gender, localisation, tumour size, recurrence free survival and overall survival. A minimum follow up of 12 months was achieved. The mean age at the point of diagnosis was 47.9 years. Metastases occurred after a mean of 19.2 months. In the cases with a tumour diameter >5 cm, metastases occurred earlier. When treated in a specialist centre, metastases occurred later. Patients died a mean of 18.4 months after developing metastatic disease. Patients with tumour size >5 cm at the point of primary diagnosis died earlier than patients with a tumour size <5 cm. It is important to detect clear-cell sarcomas as soon as possible and the final surgical treatment should be performed in a centre familiar with the treatment of soft tissue tumours not only to prolong overall survival, but also to treat the patient in a multiprofessional team.

Chemotherapy in clear cell sarcoma.

Clear cell sarcoma is a rare translocation-related sarcoma. There have been few studies documenting the response rate and progression-free survival in clear cell sarcoma patients treated with palliative chemotherapy. The prospectively maintained databases of two referral centres were searched to identify clear cell sarcoma patients treated with chemotherapy. Twenty-four patients were treated with palliative first-line chemotherapy with a median age of 30 years at diagnosis. There were 18 men and 6 women. One (4%) achieved a partial response and 9 (38%) had stable disease. Fourteen patients (58%) progressed on therapy. The median progression-free survival was 11 weeks (95% CI, 3­20 weeks). The median overall survival from commencing first-line chemotherapy was 39 weeks (95% CI, 34­45 weeks). Second-line chemotherapy was administered to 12 patients, 11 (92%) of these progressed and one (8%) had stable disease. Of the 5 patients treated with third-line chemotherapy, 4 (80%) progressed and one (20%) had stable disease. One patient received fourth-line chemotherapy and maintained stable disease for 4 months. Conventional chemotherapy has minimal activity in clear cell sarcoma as documented by the response rate of 4% and median progression-free survival of 11 weeks in this retrospective series. These data provide a reference for response and outcome in the assessment of novel agents in this histological subtype.

Pediatric non-Wilms renal tumors: subtypes, survival, and prognostic indicators.

BACKGROUND: To determine the outcomes and predictors of survival for pediatric non-Wilms renal tumors (NWRT). METHODS: The SEER database (1973-2005) was queried for all patients < 20 y of age. RESULTS: Overall, 349 cases of NWRT were identified. The major histologic groups included renal cell carcinoma (RCC) (44%), clear cell sarcoma of the kidney (CCSK) (17%), and malignant rhabdoid tumor (MRT) (12%). A bimodal age distribution was observed, with tumors commonly presenting in patients ≤4 y of age and ≥15 y of age. More than 50% of RCC presented at ≥15 y of age, whereas ≥80% of CCSK or MRT patients were ≤4 y of age. Most RCC (57%) and CCSK (53%) were locally staged while most MRT presented with distant disease (51%, P < 0.001). Overall 10-y survival was 63% with improved survival observed in patients with CCSK (79%) and RCC (70%) versus MRT (29%, P < 0.001). By univariate analysis, surgical resection was associated with improved overall 10-y survival (68% versus 30%, P < 0.001), while no benefit was observed for radiotherapy (60% versus 63%, P = 0.8). By multivariate analysis, worse overall survival was observed for patients ≥ 10 y old (HR 4.01, P = 0.013) and those with advanced disease (HR = 12.78, P < 0.001). Patients with MRT (HR = 11.61, P < 0.001) and CCSK (HR = 3.68, P = 0.038) had significantly worse prognosis compared with those with RCC. Surgical resection improved overall survival (HR = 0.36, P = 0.001). CONCLUSION: For pediatric NWRT, younger patients and those with RCC have improved survival, while a diagnosis of MRT portends a worse prognosis. Surgical extirpation significantly improves survival for all patients.