Outcomes of eosinophilic renal neoplasms following renal biopsy

Available accessAbstractFirst published online August, 2020

Outcomes of eosinophilic renal neoplasms following renal biopsy

Volume 65, Issue 3https://doi.org/10.1177/0036933020934664

Abstract

J Shin¹, V Lynch², D Alcorn³, S Sheridan³, D Kay³ and N Umez-Eronini⁴

¹Clinical Research Fellow, Department of Urology, Glasgow Royal Infirmary, NHS Greater Glasgow & Clyde, UK

²Consultant Pathologist, Department of Pathology, Queen Elizabeth University Hospital, NHS Greater Glasgow & Clyde, UK

³Consultant Radiologist, Department of Radiology, Gartnavel General Hospital, NHS Greater Glasgow & Clyde, UK

⁴Consultant Urological Surgeon, Department of Urology, Glasgow Royal Infirmary, NHS Greater Glasgow & Clyde, UK

Background: Eosinophilic renal neoplasms comprise of a spectrum of tumours ranging from benign oncocytoma to aggressive renal cell cancers. Identification of malignant pathology in biopsy specimens is recognised to be a diagnostic dilemma and can have significant impact on patient management.

Methods: A prospectively maintained database of all renal biopsies between March 2015 to June 2017 was reviewed and clinical information of all patients with eosinophilic histology was collated to determine outcome and accuracy of prediction of malignancy.

Results: 28 renal biopsies were identified with eosinophilic neoplasm pathology. Average number of cores were 3 (median 3, range 1–6). On histology, 14 biopsies favoured oncocytoma and 12 favoured chromophobe renal cell carcinoma (RCC). 1 case could not be distinguished between oncocytoma and chromophobe RCC but no progression was seen during active surveillance. Table 1 summarises the outcomes following renal biopsy.

Conclusion: The use of renal biopsy in the evaluation of small renal masses is established practice. Even in the presence of eosinophilic pathology, biopsy can guide appropriate management. In our cohort of patients, active surveillance of likely oncocytoma pathology still resulted in active treatment due to growth kinetics and radiological concern in 65% of cases (n = 9), with one case demonstrated to have RCC on partial nephrectomy.

Table 1.
Outcomes of eosinophilic renal neoplasms following renal biopsy.

Biopsy favours oncocytoma (n = 14) Biopsy favours chromophobe RCC (n = 12) Biopsy cannot distinguish oncocytoma or RCC (n = 1)

Active surveillance (ongoing) 4 0 1

Cryoablation 7 5 0

Partial nephrectomy 1^a 5^d 0

Radical nephrectomy 1^b 1^d 0

Patient not suitable for surgery 1^c 1 0

^ahistology confirmed pT3a RCC.

^bradiological suspicion of malignancy; histology confirmed oncocytoma and angiomyolipoma.

^cdied from haemorrhagic cerebellar metastasis following biopsy.

^dall confirmed as RCC.