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.

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.

Outcome of pediatric renal tumor treated using the Japan Wilms Tumor Study-1 (JWiTS-1) protocol: a report from the JWiTS group

PURPOSE

In 1996, the Japan Wilms Tumor Study (JWiTS) group was founded to elucidate the efficacy and safety of the regimen established by the National Wilms Tumor Study (NWTS) group in the USA, and a multicenter cooperative study (JWiTS-1) was started in Japan. This report reviews the results of JWiTS-1.

METHODS

A total of 307 patients with malignant renal tumor were enrolled in the JWiTS-1 study between 1996 and 2005. Central pathological diagnosis and follow-up data were available in 210 cases. The protocol regimens were similar to the NWTS-5 regimens. Clinical stage was classified according to the Japanese Staging System.

RESULTS

Five-year overall survival (OS) rate was 91.1% for nephroblastoma, 72.9% for clear cell sarcoma of the kidney (CCSK), and 22.2% for rhabdoid tumor of the kidney (RTK). In the nephroblastoma patients, 5-year OS was 90.5% for stage I disease, 92.2% for stage II, 90.9% for stage III, 86.7% for stage IV, and 78.7% for stage V.

CONCLUSIONS

The OS of patients in the JWiTS-1 study were comparable with the results of other multicenter studies in the USA and Europe. The outcome for patients with nephroblastoma and CCSK was fair. In contrast, the cure rate for those with RTK was not satisfactory. New treatment strategies are needed for patients with RTK.

Malignant melanoma of soft parts. A "non plastic surgeon's land"?

Malignant melanoma of soft parts (MMSP) (or "clear cell sarcoma") is a very rare tumour that shows up without primitive skin involvement (except in subcutaneous prolongations of deep tumours), mostly predominant in the extremities of young adults. Eight files of MMSP were studied retrospectively. The mean patient is a male of 35 years old affected in an extremity (four upper, three lower and one gluteal), according to classical descriptions. The importance of radical surgery in these cases has been extensively established. Confronted with these cases, the plastic surgeon must be aware of the specifics of this rare entity to ensure its proper inclusion in his clinical suspicion. Just in case.

Clear cell sarcoma of soft tissues

Clear cell sarcoma (CCS) is a rare but highly malignant tumor of soft tissues often appearing as a small tender mass in the deep tissues of the distal extremities. We have studied 17 patients with such lesions treated since 1986 and have a high incidence of local recurrence and metastasis with a survival rate of only 47% despite surgery and for many of the patients, adjuvant therapy. The purpose of this article is to warn the readers of the dangers related to treating this seemingly benign lesion and urge them to perform wide surgery and utilize adjuvant therapy.

Clear cell sarcoma of tendons and aponeuroses: a study of 75 patients

BACKGROUND

Clear cell sarcoma (CCS) of tendons and aponeuroses (malignant melanoma of soft parts) is a rare melanocytic soft tissue sarcoma. The objective of this study was to determine the clinical features, prognostic factors, and optimal treatment policy for patients with this rare disease.

METHODS

Seventy-five consecutive patients with histologically confirmed CCS who received treatment between 1980 and 2004 were analyzed retrospectively.

RESULTS

There were 41 men and 34 women, and the median age was 36 years. Sixty-five tumors were located in the extremities, and 10 tumors were located in the trunk. The median tumor size was 4 cm. Seventy-one patients underwent surgical excision, and 56 patients received chemotherapy. Sixteen patients developed local recurrences, and 52 patients developed metastasis. The overall patient survival rates was 47% at 5 years and 36% at 10 years. Univariate analysis showed that sex (P = .018), tumor size (P = .001), tumor depth (P = .002), TNM classification (P = .001), and surgical margin (P = .042) were significant prognostic factors. Among the 52 patients who presented with localized disease, sex (P = .023), tumor size (P = .002), tumor depth (P = .011), TNM classification (P = .004), and chemotherapy (P = .032) were identified as significant prognostic factors. Multivariate analysis showed that tumor size remained an independent prognostic factor in both groups.

CONCLUSIONS

The current results supported the contention that early diagnosis and initial wide excision are essential for a favorable outcome of CCS. The role of chemotherapy for CCS should be investigated further.

Clear cell sarcoma of tendons and aponeuroses: a historical perspective and tribute to the man behind the entity

Clear cell sarcoma of tendons and aponeuroses is a unique sarcoma initially described by Dr Franz M. Enzinger. The tumor has a proclivity to involve the tendons and aponeuroses of distal extremities of relatively young individuals and is characterized by multiple local recurrences with late metastases and a high rate of tumor deaths. Since its seminal description in 1965, there have been many studies verifying the uniqueness of this entity and probing its differentiation. Ultrastructural and immunohistochemical studies have shown melanocytic differentiation, whereas molecular genetic studies have shown cytogenetic rearrangements resulting in a EWSR1-ATF1 fusion gene that is characteristic but not entirely unique for clear cell sarcoma (similar fusion genes are also seen in angiomatoid fibrous histiocytoma). Detection of this fusion gene and the absence of BRAF gene mutations clearly distinguish clear cell sarcoma from cutaneous melanoma. Adverse prognostic factors identified to date include larger tumor size and any microscopic tumor necrosis. Surgery is the mainstay of treatment for this high grade sarcoma, with chemotherapy having little effect. Although the melanocytic differentiation of clear cell sarcoma is indisputable, its precise lineage remains unclear. Thus, clear cell sarcoma maintains the status of a unique yet enigmatic clinicopathologic entity of ever increasing complexity 40 years after its original description by an extraordinarily gifted man.

Loss of heterozygosity for chromosomes 1p and 16q is an adverse prognostic factor in favorable-histology Wilms tumor: a report from the National Wilms Tumor Study Group

PURPOSE

To determine if tumor-specific loss of heterozygosity (LOH) for chromosomes 1p or 16q is associated with a poorer prognosis for children with favorable-histology (FH) Wilms tumor entered on the fifth National Wilms Tumor Study (NWTS-5).

PATIENTS AND METHODS

Between August 1995 and June 2002, 2,021 previously untreated children with FH or anaplastic Wilms tumor, clear-cell sarcoma of the kidney (CCSK) or malignant rhabdoid tumor of the kidney (RTK), were treated with stage- and histology-specific therapy. Their tumors were assayed for LOH for polymorphic DNA markers on chromosomes 1p and 16q. ResultsLOH for 1p or 16q was rarely observed in CCSK (n = 90) or RTK (n = 22). The relative risk (RR) of relapse for patients with FH stage I to IV tumors with LOH, stratified by stage, was 1.56 for LOH 1p (P = .01) and 1.49 for LOH 16q (P = .01), whereas the RR of death was 1.84 (P = .03) and 1.44 (P = .15), respectively. When the effects of LOH for both regions were considered jointly among patients with stage I to II FH disease, the risks of relapse and death were increased for LOH 1p only (RR = 2.2, P = .02 for relapse; RR = 4.0, P = .02 for death), for LOH 16q only (RR = 1.9, P = .01 and RR = 1.4, P = .60) and for LOH for both regions (RR = 2.9, P = .001 and RR = 4.3, P = .01) in comparison with patients with LOH at neither locus. The risks of relapse and death for patients with stage III to IV FH tumors were increased only with LOH for both regions (RR = 2.4, P = .01 and RR = 2.7, P = .04).

CONCLUSION

Tumor-specific LOH for both chromosomes 1p and 16q identifies a subset of FH Wilms tumor patients who have a significantly increased risk of relapse and death. LOH for these chromosomal regions can now be used as an independent prognostic factor together with disease stage to target intensity of treatment to risk of treatment failure.

Outcome of patients with stage III or inoperable WT treated on the second United Kingdom WT protocol (UKWT2); a United Kingdom Children's Cancer Study Group (UKCCSG) study

BACKGROUND

The aims of UKWT2 included consolidating the results for stage III patients obtained in UKWT1 and improving the outcome for patients with inoperable tumours by giving vincristine, actinomycin-D and doxorubicin in an intensive schedule (Intensive AVA).

PROCEDURE

The second UK WT trial (UKWT2) ran between July 1986 and September 1991 accruing 448 patients. One hundred and six patients were diagnosed and treated for stage III disease. Six had clear cell sarcoma of the kidney (CCSK) and seven had rhabdoid tumours of the kidney (RTK) and are analysed separately. One other patient was excluded from overall analysis. Ninety-two patients were followed for a median of 115 months. Seventy-five received standard chemotherapy and abdominal radiotherapy according to protocol. Seventeen had stage III disease at immediate nephrectomy, but radiotherapy was omitted by physician choice. Thirty-three patients had inoperable disease at diagnosis and received pre-nephrectomy chemotherapy.

RESULTS

Overall survival (OS) at 4 years for stage III favourable histology (FH) patients receiving abdominal RT was 83% (CI: 73-89). For children with stage III disease in whom RT was omitted the OS was 82% (CI: 59-97) and for inoperable disease 94% (CI: 78-98). The overall and event-free survival (EFS) of children with stage III CCSK was 100% and was achieved with the majority of patients not receiving radiotherapy (CI: 48-100). Three of seven children with RTK are alive EFS and OS 43% (CI: 10-73). For patients treated by abdominal radiotherapy the overall local control rate was 94.4% (CI: 86.4-98.5*%), 96.7% (CI: 88.5-99.6%) for flank RT and 83.3% (51.6-98.0%) for whole abdominal radiotherapy (WRT).

CONCLUSIONS

The outcome for stage III FH disease was similar to that reported for UKWT1 and NWTS-3. The combination of abdominal RT together with 3-drug chemotherapy achieves a high abdominal tumour control rate. Flank RT is probably sufficient for localised tumour rupture. The high cure rates for children in this trial with 'inoperable disease' suggests that treatment should be modified according to their post-chemotherapy stage in order to avoid over-treatment. The high OS for stage III CCSK on this protocol suggests that treatment duration could be curtailed and the role of RT reviewed, though the numbers are small. The prognosis for older children with RTK seems to be better than for younger children although larger studies are required to confirm this.

Results of the SIOP 93-01/GPOH Trial and Study for the Treatment of Patients with Unilateral Nonmetastatic Wilms Tumor

BACKGROUND

The treatment of Wilms Tumor is integrated into clinical trials since the 1970's. In contrast to the National Wilms Tumor Study Group (NWTSG) the SIOP trials and studies largely focus on the issue of preoperative therapy to facilitate surgery of a shrunken tumor and to treat metastasis as early as possible.

PATIENTS AND METHODS

In the SIOP 93-01/GPOH trial and study 1 020 patients with a newly diagnosed renal tumor were registered. 847 of them had a histological proven Wilms Tumor, of whom 637 were unilateral localized, and 173 tumors had an other histology [40 congenital mesoblastic nephroma (CMN), 51 clear cell sarcoma (CCSK), 24 rhabdoid tumor (RTK) and 58 other tumors]. Preoperative chemotherapy in benign tumors was given to 1.3 % of the patients. The main objective of the trial was the randomized question, if the postoperative two drug chemotherapy for stage I in intermediate risk or anaplasia can be reduced from conventional 3 courses to an experimental 1 course without loss of efficacy.

RESULTS

519 patients with unilateral nonmetastatic Wilms did receive preoperative chemotherapy. The histology in this group of patients was of intermediate risk in 469 (90 %) patients, 14 (3 %) tumors were low risk and 36 (7 %) high risk. The stage distribution of the tumors was stage I in 315 (61 %), stage II N- in 126 (24 %), stage II N+ in 25 (5 %) and stage III in 36 (7 %) patients. In 17 (3 %) patients the tumor stage remained unclear. Tumor volume was measured in 487 patients before and in 402 after preoperative chemotherapy. The median tumor volume did shrink from 353 to 126 ml. The amount of volume reduction depends on the histological subtype. The event free survival (EFS) after 5 years was 91 % for all patients with unilateral Wilms tumor without distant metastasis. Randomisation was done in 43.7 % for stage I patients and there was no difference in EFS for both treatment arms (90 versus 91 %). The EFS is identical for patients with stage I and II N- (0.92), as well as for stage II N+ and III (0.82). The tumor volume after chemotherapy is a prognostic factor for intermediate risk tumors with the exception of epithelial and stromal predominant tumors. These two subtypes often present as large tumors, they do not shrink during preoperative chemotherapy but they still have an excellent prognosis. On the other hand the prognosis of patients with blastemal predominant subtype after preoperative chemotherapy is worse than in any other patient group of intermediate risk tumors. There are less blastemal predominant tumors compared to primary surgery, but they are chemotherapeutic resistant selected by the preoperative chemotherapy.

CONCLUSION

Patients with unilateral Wilms tumor without metastasis have an excellent prognosis. The post-operative chemotherapy in stage I can be reduced to 4 weeks without worsening treatment outcome. The reduction of the tumor volume could be identified as a helpful marker for stratification of post-operative treatment. Post-chemotherapy blastemal predominant subtype of Wilms tumor has to be classified as high risk tumor. Focal anaplasia has a better prognosis than diffuse anaplasia and will be classified as intermediate risk tumor.

Effect of Duration of Treatment on Treatment Outcome for Patients With Clear-Cell Sarcoma of the Kidney: A Report From the National Wilms' Tumor Study Group

Purpose

To evaluate the effect of conventional and standard (ST) versus pulse-intensive (PI) chemotherapy and short-duration versus long-duration chemotherapy on relapse-free survival (RFS) and overall survival rates of patients with clear-cell sarcoma of the kidney (CCSK) entered onto the National Wilms' Tumor Study (NWTS)-4.

Patients and Methods

The 5-year and 8-year RFS rates were determined for patients with CCSK treated on the NWTS-4. After August 6, 1986, 40 previously untreated children younger than 16 years with CCSK were randomly assigned, after the completion of 6 months of chemotherapy, to discontinue (short) or continue 9 additional months (long) of treatment with chemotherapy regimens that included vincristine and either divided-dose (ST) courses (5 days) or single-dose (PI) treatment with dactinomycin and divided-dose (ST) courses (3 days) or single-dose (PI) treatment with doxorubicin.

Results

For patients with CCSK, the 5- and 8-year RFS rates were 65.2% and 60.6%, respectively, for patients randomly assigned to the short chemotherapy and 87.8% (both 5- and 8-year RFS) for patients randomly assigned to the long chemotherapy (P = .08). The overall survival rates for patients at 5 and 8 years were 95.5% and 85.9%, respectively, for the short chemotherapy and 87.5% (both 5- and 8-year overall survival) for the long chemotherapy (P = .99). In NWTS-4, the overall survival rates for patients with CCSK improved from NWTS-3 (83% v 66.9% at 8 years, respectively; P < .01).

Conclusion

CCSK patients exhibit an improved RFS from a longer course of therapy when using vincristine, doxorubicin, and dactinomycin, but their long-term survival is unchanged compared with patients receiving 6 months of therapy. The overall survival rates for patients with CCSK have improved from NWTS-3.

Clear cell sarcoma of tendons and aponeuroses in pediatric patients: a report from the Italian and German Soft Tissue Sarcoma Cooperative Group

BACKGROUND

Clear cell sarcoma (CCS) of tendons and aponeuroses is extremely rare in childhood and little information is available on its clinical management. Originally believed to be a type of melanoma of soft tissue origin, CCS is now considered a distinct clinicopathologic entity that behaves like a high-grade soft tissue sarcoma. We report on a series of 28 pediatric patients treated from 1980 to 2000 by the Soft Tissue Sarcoma Italian Cooperative Group and the German Cooperative Group.

METHODS

Patients were treated with a multimodality therapeutic approach. Surgical resection was complete in 17 patients (mutilating in 3), radiotherapy was administered to 8 patients, and 20 patients received chemotherapy.

RESULTS

After a median follow-up of 102 months (range, 19-238 months), the 5-year and event-free survival rates were 66.4% and 63.3%, respectively. Seventeen patients were alive in first remission, two were alive in second remission, and nine had died of disease. The response to chemotherapy in the 7 evaluable patients included one partial remission, one minor response, and five no responses. Radiotherapy contributed to achieving local control in four of six Intergroup Rhabdomyosarcoma Study (IRS) Group II patients. Statistically significant differences in outcome were evident according to IRS group, tumor size, and site.

CONCLUSIONS

Our study confirms the aggressive behavior of CCS. Complete surgical resection represents the mainstay of treatment, and even the only treatment for patients with small tumors. Radiotherapy may control microscopic residual disease after surgery. Chemotherapy is ineffective and the prognosis is unfavorable for patients with unresectable and large tumors.

Clear cell sarcoma of the pediatric kidney: detailed description and analysis of variant histologic patterns of a tumor with many faces

Clear cell sarcoma of the kidney is the most frequently misdiagnosed renal tumor in children. The majority of tumors present the classic histologic pattern, which allows a definitive diagnosis. However, there are unusual cases with lack of "clear" appearance of tumor cells, predominance or exclusive presence of variant histologic patterns, and presence of "neoplastic" appearing entrapped tubules. Furthermore, a small biopsy specimen may not show the classic histologic pattern. These tumors present a diagnostic challenge for the practicing pathologist who should be aware of the deviations from the classic histologic features in order to make a correct diagnosis.

Surgical tactics in the treatment of malignant renal tumors in childhood

The authors report the treatment results of 89 children with renal tumors (excluding carcinoma) seen from 1988 to 1992, 71 (79.8%) with favorable-histology Wilms' tumor (survival 86%) and 18 (20.2%) with unfavorable histology, including anaplastic nephroblastoma, clear-cell sarcoma, and rhabdoid tumor (survival 61%). Preoperative chemotherapy (ChT) was given to 46 patients (survival 84%); none was given to 43 with either tumors in the 1st year of life, massive hematuria, or tumor growth during ChT (survival 78%). There were 3 tumor ruptures in the latter group compared to 1 in the former group.