Histopathology:
Left radical nephrectomy for cystic renal mass.
Almost the entire kidney has been replaced by a cystic tumour, with a small amount of residual normal appearing kidney 55x25x25 mm evident at the inferomedial aspect).
The cut surface of the tumour is multiloculated and cystic with cystic spaces measuring between 2 and 40 mm in maximum extent. The cyst walls are thin and smooth with a maximum septal thickness of 3 mm. No solid areas are seen. The tumour appears to bulge into and expand the renal sinus spaces and also involves the proximal ureter over a length of approximately 10 mm (remainder of ureter appears clear). The tumour does not breach the renal capsule. No involvement of renal vein or artery is macroscopically apparent.
CONCLUSION:
Paediatric cystic nephroma