Experience with neoadjuvant diethylstilboestrol and radical prostatectomy in patients with locally advanced prostate cancer.

OBJECTIVE

To report our experience with neoadjuvant endocrine therapy and radical retropubic prostatectomy (RRP) in patients with locally advanced prostate cancer.

PATIENTS AND METHODS

Fifty-five patients with prostatic adenocarcinoma (18 clinical stage B2/3, 27 clinical stage C, and 10 clinical stage D0) were treated with diethylstilboestrol (DES) 3 mg/d (median time 12 weeks, range 5-36) followed by pelvic lymph node dissection and planned RRP. Clinical response was monitored bi-weekly with serum prostate-specific antigen (PSA), serum acid phosphatase and digital rectal examination.

RESULTS

The median pre-treatment serum PSA was 20.4 ng/ml (range 1.2-620). The median post-treatment, pre-operative serum PSA was 0.4 ng/ml. Twenty-seven (49%), 41 (75%) and 54 (98%) patients had serum PSA levels that were undetectable, < 1.0 ng/ml and < 4.0 ng/ml respectively. In 15 patients, transrectal ultrasound measurement of prostatic volume changes was performed, and all demonstrated prostate volume reduction (median reduction 35%, range 18-45). All 55 patients underwent pelvic lymphadenectomy, with 47 (85%) undergoing RRP. Of the eight patients not undergoing RRP, three had negative lymph nodes but prostate resection was not deemed feasible and five had nodal metastases as determined by frozen section analysis. Final pathological stage revealed the following distribution: organ confined tumours, 18 (33%); capsular perforation with negative surgical margins, seminal vesicles and lymph nodes, seven (13%); seminal vesicle and/or margin involvement with negative lymph nodes, 18 (33%); lymph node metastases, 12 (22%). Neither pre-therapy serum PSA nor serum PSA response was predictive of final pathological stage. With a median follow-up interval of 26 months (range 12-49), 21 patients (38%) have undetectable serum PSA without adjuvant therapy.

CONCLUSIONS

Our results indicate that despite clinical evidence suggestive of downstaging, the majority of patients with locally advanced prostatic carcinoma managed with neoadjuvant DES and RRP continue to have pathological evidence of extraprostatic carcinoma.