INFLAMMATORY PSEUDOTUMOR OF THE URETER AND THE URINARY-BLADDER

Inflammatory pseudotumor (LPS) of the urinary bladder was first descri bed in 1980. We report four cases of LPS which occurred during the las t four years. One tumor occurred in the bladder of a 49-year-old woman five months after abdominal hysterectomy of uterine leiomyomas, two t umors in a 35- and 39-year-old woman, respectively, without antecedent al surgical intervention (though one with recidive after six months). The fourth occurred in a 64-year-old male in the proximal ureter by py elonephritis. Two cases were initially diagnosed at frozen section dur ing operative treatment, the others on paraffine section after immunoh istochemical examination. Two cases showed an aberrant expression of c ytokeratines. There is no evidence of recidive tumor within a mean fol low up of 25 months (12-49 months). Features to differentiate benign f rom malignant spindle cell lesions of the lower urinary tract are the absence of atypical mitoses, significant cytologic atypia, absence of necroses within the tumor (rather on its surface), no destructive grow th at the tumor margins and low cellularity. Usually, IFS show a submu cosal edematous area with a deeper, highly cellular component. The cli nical history of a recent bladder operation or gynecologic surgery is of upmost importance in making the diagnosis of IFS. Complete surgical excision, either by transurethral resection or partial cystectomy app ears to be curative for IPS.