Bilateral benign renal oncocytomas and the role of renal biopsy: single institution review

Abstract

BackgroundThe goal was to assess the natural history and management of patients with pathologically proven bilateral (synchronous) RO after undergoing initial partial nephrectomy (PN).MethodsAll patients underwent either robotic/laparoscopic or open PN by two experienced genitourinary oncologists from 2005–2013. Final pathology was determined by surgical excision, CT-guided percutaneous core biopsy (CT-biopsy) or fine needle aspiration (FNA). Patient demographics, tumor characteristics (pathologic data, location, size) type of surgery, pre/post estimated glomerular filtration rate (eGFR) and surgical complications were recorded.ResultsTwelve patients were identified with bilateral RO. Median age at the time of surgery was 68 years (46–77) (Table 1). The median size of the largest tumor(s) resected was 2.75 cm (1.5–5.5 cm) and second largest tumor(s) was 1.75 cm (1.0–4.0 cm). Four patients underwent bilateral staged PN and one patient underwent simultaneous bilateral PN (horseshoe kidney). Two patients underwent RFA at the time of biopsy of the contralateral mass after PN. Five patients underwent CT-bx/FNA (5/5) of the contralateral mass followed by active surveillance.Mean follow up was 34 months. There was no significant change in median creatinine pre- and post-operatively. One patient was lost to follow up and one patient died of unknown causes 5 years post-operatively. eGFR decreased an average of 16.96% post-operatively, including a single patient whose eGFR increased by 7.8% after surgery and a single patient whose eGFR did not change (Table 2).ConclusionsPatients with bilateral renal masses and pathologically proven RO can be safely managed with active surveillance after biopsy confirmation of the contralateral mass.

Triple Threat: Three Primary Malignancies Simultaneously Involving Three Genitourinary Organs

“…Certain types of renal tumors, such as oncocytoma, may be very challenging to differentiate from malignant renal masses [ 7 ]. As any surgical intervention to remove a renal mass appropriately will worsen renal function to some degree, understanding if bilateral renal surgical manipulation is truly warranted prior to time of surgery is a priority.…”

Bilateral Renal Oncocytoma: Active Surveillance Versus Partial Nephrectomy

“…The patient could have undergone a confirmatory biopsy of the contralateral right renal mass with AS imaging protocols instead of undergoing a right PN [ 13 ]. PNs are associated with complications such as postoperative hemorrhage and urine leak, such that for every 1 cm increase in tumor diameter, the risk of postoperative hemorrhage increases by 45% [ 14 ].…”

Artificial Intelligence in Renal Cell Carcinoma Histopathology: Current Applications and Future Perspectives

“…A significant proportion of small renal masses (SRMs) are benign, with oncocytoma being the most frequent benign contrast-enhancing renal mass found. A well-known problem faced by pathologists is differentiating oncocytomas from chromophobe RCC [ 56 , 57 , 58 ]. Zhu et al reported favorable results in RCC subtyping in surgical resection and RMB specimens, as well as promising results in oncocytoma diagnosis in RMB [ 59 ].…”