Clinicopathological characteristics of surgically treated localized renal masses in patients previously exposed to chemotherapy

PURPOSE: To explore the potential association between renal mass characteristics and a history of chemotherapy. MATERIALS AND METHODS: A retrospective review of records of patients surgically treated for a localized renal mass between 2000 and 2012 was undertaken following an institutional review board approval. Patients age and sex, renal mass clinical characteristics (radiological size and mode of presentation) and pathological characteristics (diagnosis, renal cell carcinoma subtype, Fuhrman grade and stage) were compared between patients with and without a history of chemotherapy, using Fisher's exact test, Student's t-test and Wilcoxon rank sum test. A multivariate logistic analysis was performed to evaluate the independent association of chemotherapy and tumor pathology. RESULTS: Of the 1,038 eligible patients, 33 (3%) had a history of chemotherapy. The distribution of clinical stage, renal mass diagnosis, renal cell carcinoma subtype, Fuhrman grade, pathological stage, sex and median age were similar between the general population and the chemotherapy group. However, the latter had a higher rate of incidental presentation (P = 0.003) and a significantly smaller median radiological tumor size (P = 0.01). In a subset analysis of T1a renal cell carcinoma, the chemotherapy group presented an increased rate of high Fuhrman grade (P = 0.03). On multivariate analysis adjusted for radiological tumor size, sex and age the chemotherapy cohort had a 3.92 higher odds for high Fuhrman grade. CONCLUSION: Patients with a history of chemotherapy typically present with smaller renal masses that, if malignant, have higher odds of harboring a high Fuhrman grade and thus may not be suitable for active surveillance.