[Sarcomatoid renal cell carcinoma]

Abstract

Introduction: The objective was to perform a systematic review of literature concerning epidemiology, clinical and biological data, prognosis and therapy of sarcomatoid renal cell carcinomas.

Material and methods: Data on sarcomatoid renal cell carcinomas have been sought by querying the server Medline with MeSH terms following or combination of them: "renal carcinoma", "renal cell carcinoma," "renal cancer", "sarcomatoid" "sarcomatoid transformation" and "sarcomatoid differentiation." The articles obtained were selected according to their methodology, the language in English or French, the relevance and the date of publication. Twenty papers were selected.

Results: According to the literature, a sarcomatoid contingent can be observed in all subtypes of renal cell carcinomas, with a frequency of 1 to 15% of cases. The median age at diagnosis was 60 years with a majority of symptomatic patients (90%), mainly with abdominal pain and hematuria. These tumors were often found in patients with locally advanced or metastatic (45-77%). The imaging was not specific for the diagnosis and biopsy had a low sensitivity for identifying a sarcomatoid contingent. The treatment was based on a combination of maximal surgical resection whenever possible and systemic therapy for metastastic disease. Pathological data often showed large tumors, Furhman 4 grades, combined biphasic carcinomatous contingent (clear cell carcinoma in most cases) and sarcomatoid. Genetically, there was no specific abnormality but a complex association of chromosomal additions and deletions. The prognosis was pejorative with a specific median survival of 5 to 19 months without any impact of the sarcomatoid contingent rate.

Conclusion: Sarcomatoid renal cell carcinoma is a form not to ignore despite its rarity. Mainly symptomatic and discovered at an advanced stage, it has a poor prognosis, requiring multidisciplinary management quickly and correctly.