Perivesical fat necrosis after adjuvant intravesical chemotherapy

To document the presence of extensive transmural and perivesical fat necrosis in a series of radical cystectomies, and associate the surgical and pathological findings with the administration of intravesical chemotherapy.

The study comprised 12 patients with pT2+ transitional cell tumours who were referred to the West Middlesex University Hospital and who proceeded to primary radical cystectomy between November 1996 and April 1998. The association between the presence of widespread transmural and extravesical necrosis and the administration of a single dose of intravesical epirubicin or mitomycin C in the 24 h after the initial transurethral resection of bladder tumour (TURBT) was analysed using the two-tailed Fisher's exact test.

The association between the presence of transmural and extravesical fat necrosis and administration of intravesical chemotherapy was highly significant (P=0.015).

The depth and extent of the mural muscle necrosis and perivesical fac necrosis in patients receiving intravesical chemotherapy within 24 h of TURBT is remarkable and more florid than the usual muscle necrosis seen after TURBT. Clinically, the necrotic tissue makes the cystectomy significantly more difficult technically, and may even mimic extravesical spread of malignant disease. This was not borne out by the histology of the specimens, which showed no extravesical spread of the tumour. Surgeons should be aware of the possibility that such operative findings might be the result of intravesical chemotherapy.