Clinical utility of indium 111-capromab pendetide immunoscintigraphy in the detection of early, recurrent prostate carcinoma after radical prostatectomy.

BACKGROUND: Despite the ability of radical prostatectomy to eradicate prostate carcinoma, biochemical evidence of recurrent prostate carcinoma may be seen in approximately 40% of patients 15 years after they undergo surgery. Localization of recurrent disease after radical prostatectomy is difficult and may greatly influence subsequent clinical management. The authors examined the utility of indium 111 ((111)In)-capromab pendetide immunoscintigraphy to detect recurrent prostate carcinoma radiographically in men with early biochemical evidence of failure (serum prostate specific antigen [PSA] < or = 4.0 ng/mL) and assessed the minimum serum PSA level necessary for imaging recurrent disease.
METHODS: Between May 1987 and August 1995, 255 hormone-naïve men with a mean (+/- standard deviation) age of 65 years +/- 7 years who underwent radical prostatectomy for clinically localized prostate carcinoma were followed without adjuvant therapy until early PSA recurrence in this multicenter study. Preoperatively, all patients had negative bone scans and pathologically negative lymph nodes, and they did not undergo hormonal ablation, chemotherapy, or radiation therapy preoperatively or postoperatively until the (111)In-capromab pendetide scan was performed. All men in this study had postoperative serum PSA levels < or = 4.0 ng/mL at the time of radionuclide imaging. All men underwent imaging with the capromab pendetide scan to localize recurrent disease, and charts were reviewed to document clinical evidence of recurrence.
RESULTS: Pathologic findings included mean Gleason scores of 6.7 +/- 1.2; pathologic tumors classified as pT2a (18%), pT2b (26%), pT3a (38%), pT3b (16%), and pT4a (2%); a pathologic lymph node status of pN0 (100%); positive surgical margins (44%); and perineural invasion (42%). Capromab pendetide uptake was seen in 72% of 255 men throughout a range of patients' postoperative serum PSA levels (0.1-4.0 ng/mL), with 31% of men having local uptake (prostatic fossa) only. Of 151 men who underwent additional imaging studies, 16 of 139 men (12%) and 15 of 92 men (16%) showed evidence of recurrent disease by bone scintigraphy and computed tomography scans, respectively. Gleason score, pathologic stage, perineural invasion, and margin status were not correlated significantly with the (111)In-capromab pendetide scan.
CONCLUSIONS: Capromab pendetide imaging can localize early PSA recurrence and may guide appropriate treatment after patients undergo radical prostatectomy. No minimum serum PSA value was needed to potentially detect radiographic disease after surgery. Further confirmatory studies and long-term follow-up of this cohort documenting response to salvage therapy are needed to validate these imaging findings. Copyright 2002 American Cancer Society. DOI 10.1002/cncr.10337