Incidentally Detected Renal Neoplasms in Nephrectomy and Postmortem Specimens, with A Review of Literature

Abstract

Introduction: Nephrectomy is commonly carried out for renal neoplasms or benign conditions such as hydro- or pyonephrosis. A variety of neoplasms are incidentally detected in these latter benign nephrectomies and also in postmortem material. The objective of this study was to document the patterns and morphology of incidentally detected renal neoplasms, which may differ somewhat from those diagnosed preoperatively, and review the relevant literature. Materials and Methods: This was a retrospective study carried out in a tertiary care hospital during a 5 years’ period (2013–2017). All kidney specimens, surgical or postmortem, where a neoplasm was found on histopathology and was not suspected preoperatively or antemortem respectively, were included in the study. The kidney specimens were processed according to standard procedures. Results: Five neoplasms were incidentally detected in a total of 19 renal specimens received, four in surgical material, and one in an autopsy. All except the autopsy specimen were found in non-functioning kidneys, with hydro- or pyonephrosis. There were two renal cell carcinomas (RCCs), two pelvic squamous cell carcinomas (SCCs), and one transitional cell carcinoma (TCC). The SCCs and one RCC were associated with renal calculi. The RCC detected postmortem was of the papillary variant, while the other one was a poorly differentiated variant. The TCC was not associated with calculi. Conclusions: Numerous incidental neoplasms are found in surgical or medicolegal renal specimens, many associated with calculi and hydro- or pyonephrosis. The neoplastic element may be masked by the overwhelming benign lesion. Thorough sampling and a high index of suspicion are needed to detect these lesions. The sample size is too small to document any morphological pattern.

Keywords

• incidental renal neoplasms
• nephrectomy
• post mortem.