KAI1 expression can be a predictor of stage A prostate cancer progression

The disease progression and rate of cancer death were analyzed in 52 patien ts with stage A prostate cancer who underwent transurethral resection of th e prostate (TURP) or retropubic subcapsular prostatectomy (SCP) between 198 7 and 1998. We performed immunohistochemistry on 16 patients to determine t he correlation between the expression of the tumor metastasis suppressor ge ne KAI1 and the subsequent progression of stage A prostate cancer. Nineteen and 33 of the patients had cancer at stage A1 and stage A2, respectively, and their subsequent courses were followed for an average of 53.7 months (2 4-134 months). Progression to clinical cancer was, found in six patients (o ne with stage A1, and five with stage A2). This progression was evident 40. 8 months (5-80 months) after TURP or SCR Four (66.7%) of the patients died of cancer progression (average 31 months) after prostatectomy. All four pat ients had stage A2, poorly differentiated adenocarcinoma, and had been foll owed with administration of diethylstilbestrol diphosphate (DES-P). The dis ease-free patients (n = 10) showed overexpression of KAI1 protein, compared to those with disease progression (n = 6). These results indicate that pro gression arose mainly in the patients with stage A2 cancer, and that poorly differentiated, focal and weak expression of KAI1 protein is highly associ ated with disease progression. It is suggested that patients in this group should be treated with immediate total androgen blockade, radiation, or rad ical prostatectomy after diagnosis.