Bilateral clear cell sarcoma of the kidney

Area of Science:

• Pediatric Oncology
• Renal Tumors
• Cancer Metastasis

Background:

• Clear cell sarcoma of the kidney (CCSK) is a rare pediatric renal malignancy (2-5% of cases).
• CCSK is recognized for its tendency to metastasize to bone and other distant sites.
• Bilateral involvement in CCSK is uncommon.

Observation:

• This report details two pediatric cases of bilateral CCSK diagnosed at a single institution.
• One patient presented with bilateral renal masses and widespread metastasis (pulmonary, hepatic, bone).
• The second patient had bilateral masses but no initial distant metastases.

Findings:

• Both patients received neoadjuvant chemotherapy; one achieved complete remission but relapsed, while the other experienced tumor progression.
• Both cases demonstrated brain dissemination at the time of relapse or progression.
• These cases highlight CCSK's potential for metastasis to the brain, even as a primary site during relapse.

Implications:

• Accurate staging and stratification are critical for effective CCSK management.
• The findings underscore the importance of considering brain metastasis in CCSK, particularly at relapse.
• Further research into CCSK metastatic patterns and treatment strategies is warranted.