INTRODUCTION AND OBJECTIVES: Concern regarding coexisting malignant pathology in benign renal tumors deters renal biopsy and questions its validity.
We examined rates of coexisting malignant and high grade pathology in resected benign solid solitary renal tumors.
METHODS: Using our prospectively maintained database we identified patients with solitary solid renal tumors who underwent surgical resection between 1994 and 2012 (n=1829). Lesions containing elements of renal oncocytoma (RO), angiomyolipoma (AML) or other benign pathology formed the basis for this analysis. Patients having an oncocytic malignancy, without presence of a classic oncocytoma, and those with known hereditary syndromes were excluded.
RESULTS: 147 patients with pathologically proven elements of RO (n=96), AML (n=44), and other solid benign pathology (n=7) were identified. Median tumor size was 3.0 cm (IQR 2.2 - 4.5) and tumor anatomic complexity, as quantified by the RENAL NS, was low in 28%, moderate in 56%, and high in 16%. Only 4 patients (2.7%) were documented as having hybrid malignant pathology, all involving low grade chromophobe RCC in the setting of RO. After a median follow-up of 44 (IQR 33 - 55) months, no patients with hybrid tumors experienced regional or metastatic progression.
CONCLUSIONS: In our cohort of patients with a solitary, sporadic, solid benign renal mass, < 3% of tumors exhibited coexisting hybrid malignancy. Importantly, no patients harbored coexisting high grade pathology. These data suggest that uncertainty regarding hybrid malignant pathology coexisting with benign pathologic components should not deter renal biopsy, especially in the elderly and comorbid.
Written by:
Ginzburg S, Uzzo R, Al-Saleem T, Dulaimi E, Walton J, Corcoran A, Plimack E, Mehrazin R, Tomaszewski J, Viterbo R, Chen DY, Greenberg R, Smaldone M, Kutikov A. Are you the author?
Division of Urologic Oncology, Department of Surgical Oncology, Fox Chase Cancer Center, Temple University, Philadelphia, PA.
Reference: J Urol. 2013 Jul 27. pii: S0022-5347(13)05007-6.
doi: 10.1016/j.juro.2013.07.059
PubMed Abstract
PMID: 23899990
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