Histologic subtypes of metastatic renal cell carcinoma (mRCC) differ in their patterns of metastatic involvement, investigators reported during the American Society of Clinical Oncology 2020 Virtual Scientific Program.
For example, lung, adrenal, brain, and pancreatic metastases occur more frequently with clear cell RCC (ccRCC) than with papillary RCC (pRCC) or chromophobe RCC (chrRCC), according to Shaan Dudani, MBChB, of Ottawa Hospital Cancer Centre, University of Ottawa, Canada, and colleagues. Lymph node involvement was most frequent papillary RCC, and liver metastases were most frequent in chromophobe RCC.
“These data highlight the clinical and biologic variability between histologic subtypes of mRCC,” the authors concluded in a poster presentation.
They also observed, “Patterns of metastatic spread may reflect differences in underlying disease biology.”
Using the International RCC Database Consortium database, the investigators identified 10,105 patients with mRCC starting systemic therapy from 2002 to 2019. At diagnosis, patients had a median age of 60 years, 72% were male, and 79% underwent nephrectomy. The distribution of histologic subtypes was 92% ccRCC, 7% pRCC, and 2% chrRCC. Median overall survival for ccRCC varied by site of metastatic involvement, ranging from 16 months for brain/pleura metastases and 50 months for pancreatic metastases.
In addition, compared with patients with ccRCC, patients with pRCC how lower overall survival (OS) regardless of site of metastases. As a result of the study’s limited statistical power, Dr Dudani and colleagues did not detect differences in OS between ccRCC and chrRCC.
Dudani S, de Velasco G, Wells C, et al. Characterizing sites of metastatic involvement in metastatic clear-cell, papillary, and chromophobe renal cell carcinoma. Presented at the American Society of Clinical Oncology 2020 Virtual Scientific Program held May 29 to 31. Abstract 5071.
J Clin Oncol. 2020;38(suppl; abstr 5071)