Chromophobe renal cell carcinoma (RCC) is a rare subtype of RCC and accounts for about 5% of all RCC cases. A recent retrospective study, published in the journal Clinical Genitourinary Cancer, looked at the clinical outcomes and genomic features of 109 patients with metastatic chromophobe RCC, of which 29 had sarcomatoid features. Sarcomatoid carcinoma is a relatively uncommon form of cancer where the malignant cells in the tumour resemble both epithelial cells (carcinoma) and mesenchymal cells (sarcoma).
The study showed that the patients with sarcomatoid features had poorer clinical outcomes than those without sarcomatoid features. Median time to recurrence (2.7 vs 48.8 months) and time to treatment failure (1.8 vs 8.0 months) were both shorter in patients with sarcomatoid features compared to those without. Median overall survival was also shorter in patients with sarcomatoid features (7.5 vs 38 months). Of 6 patients who did not respond to nivolumab therapy, 4 had sarcomatoid features.
The researchers conclude that because of poor clinical outcomes in patients with metastatic chromophobe RCC with sarcomatoid features, these patients need close surveillance following nephrectomy. Additional research into the biology of chromophobe RCC with sarcomatoid features is warranted to identify new treatments for this group of patients.