Erkenntnisse und Ergebnisse einer prospektiven klinischen Phase II Studie zur Chemotherapie des hormonrefraktären Prostatakarzinoms

Prostate cancer is one of the most common cancers in men with often unsatisfactory results in the efficacy of chemotherapy. In order to evaluate the feasibility, toxicity and therapeutic efficacy of a therapy with the pegylated form of doxorubicin (CaelyxR) in two different doses that have not been studied so far in a clinical setting; a prospective, randomized clinical trial was performed. Forty-eight patients with symptomatic hormone-refractory prostate-carcinoma (HRPCA) received 12 cycles of pegylated liposomal doxorubicin at 25 mg/m2 every 2 weeks (Group A) or 6 cycles of 50 mg/m2 every 4 weeks (Group B). Therapeutic efficacy was assessed by serial evaluation of serum prostate-specific-antigen (PSA) concentrations and by serial measurement of pain levels. An objective decrease in PSA levels (> 50%) was observed in 8 out of 30 patients (26,7%) in group B, whereas no other patient in group A showed a similar decrease. Severe side effects were observed in 24 patients (50%) experiencing World Health Organization Grad 3/4 toxicity. Toxicity types differed significantly between group A and B, palmar-plantar erythrodysesthesia developed in 60% of patients in the former group whereas tachycardia was more common in the latter group. Pegylated liposomal doxorubicin yielded a noteworthy objective palliative response rate and a mean survival of 13 months for patients with symptomatic HRPCA in agreement with other studies. A positive effect for mean survival is not detectable in contrast to a Taxane based regime with Docetaxel. The dosage tested in the current study should be used in future trials of pegylated liposomal doxorubicin-containing combination regimens for patients with HRPCA.