Ketoconazole retains activity in advanced prostate cancer patients with progression despite flutamide withdrawal.
OBJECTIVE
We tested the hypothesis that certain patients with hormone refractory prostate cancer retain hormonal sensitivity even after progression following antiandrogen withdrawal. The efficacy of ketoconazole and hydrocortisone in this patient population was evaluated.


METHODS
A total of 50 consecutive patients with advanced prostate cancer received ketoconazole and hydrocortisone at progression after antiandrogen withdrawal. Prostate specific antigen (PSA) response was defined as greater than a 50% decrease in PSA from baseline that was maintained for at least 8 weeks.


RESULTS
Overall, of 48 evaluable patients 30 (62.5%, 95% confidence interval 47.3 to 76.1%) had greater than a 50% decrease in PSA, while 23 (48%) had greater than an 80% decrease. The median duration of response was 3.5 months but 23 of 48 patients continue to exhibit a response, ranging from 3.25 to 12.75 or more months. The ketoconazole response rate in patients with no response to prior antiandrogen withdrawal was not different from that in patients with such a response (65 versus 40%, p = 0.35). Toxicity was mild. Grade 1 or 2 nausea, fatigue, edema, hepatotoxicity and rash occurred in 10.4 (5 of 48), 6.25, 6.25, 4.2 and 4.2% of patients, respectively, and anorexia occurred in 2%.


CONCLUSIONS
Failure to respond to antiandrogen withdrawal does not identify patients with truly hormone refractory disease. Ketoconazole retains significant activity in this setting and is extremely well tolerated.
Small
E J
EJ
Department of Medicine, University of California, San Francisco Cancer Center 94115, USA.
Baron
A D
AD
Fippin
L
L
Apodaca
D
D
D000368:Aged; D000369:Aged, 80 and over; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage; D018450:Disease Progression; D005485:Flutamide / Q000008:administration & dosage; D006801:Humans; D006854:Hydrocortisone / Q000627:therapeutic use*; D007654:Ketoconazole / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000473:pathology
D018931:Antineoplastic Agents, Hormonal; D005485:Flutamide; D007654:Ketoconazole; D006854:Hydrocortisone