Perilobar Nephrogenic Rest
Also written as: PLNR — Perilobar Nephrogenic Rest
A cluster of abnormally persistent embryonal renal cells located at the periphery of the renal lobe, regarded as a precursor to Wilms tumour.
Full Definition
Perilobar nephrogenic rests (PLNRs) are foci of residual metanephric blastema situated in the cortex at the periphery of the renal lobe, as opposed to intralobar nephrogenic rests, which occur deeper within the renal parenchyma. PLNRs are more commonly multifocal and bilateral and are particularly associated with Wilms tumours of the epithelial or stromal subtype and with syndromes such as Beckwith–Wiedemann. Their recognition and accurate classification in pathology reports determine follow-up surveillance protocols under institutional and cooperative-group guidelines. Editors should note that the hyphenated form 'perilobar' is standard; the variant 'peri-lobar' is non-preferred.
Usage
Usage note: Always specify 'perilobar' or 'intralobar' when documenting nephrogenic rests; the unqualified term alone is insufficient in a surgical pathology or oncology report.
In Context
- "Multiple perilobar nephrogenic rests were identified in the contralateral kidney, prompting enhanced surveillance imaging." — Surgical pathology report
- "The report distinguished perilobar nephrogenic rests from intralobar rests, as the distinction influences surveillance frequency." — Multidisciplinary tumour board summary