Cooperative study of pirarubicin against urological cancers and future direction of its combination use. The Clinical Study Group of THP for Urological Malignant Tumors.

In the urological field, one of the most effective drugs is doxorubicin. A cooperative phase II study on pirarubicin (THP), a new anthracycline with less cardiotoxicity than doxorubicin, was performed in 14 institutions for treating urological tumors. THP was administered intravenously 3 or more times (as one course, 30-40 mg/m2 once a week, every 3 weeks or 20 mg/m2 2 consecutive days a week every 3 weeks). Fifty-four of the 63 patients included in this study were evaluable. An overall efficacy rate was 18.5% (10/54), consisting of transitional cell carcinoma 24.3% (9/37; bladder cancer 6/27 (22.2%), tumors of the renal pelvis and ureter 3/10 (30.0%), and prostatic cancer 1/15 (6.7%). Adverse effects were mostly slight especially alopecia (15.9%, WHO grade 1:7 patients and grade 2:3 patients), and there was no problem attributable to cardiotoxicity of THP. Leukocytopenia was seen for 65.1% (grade 1:14 patients, grade 2:13 patients, grade 3:13 patients, and grade 4:1 patients). The nadir was observed about 2 weeks later and it took about 2 weeks for the recovery. Thus, it can be concluded that the usefulness of THP in treating urological tumors is comparable to or better than that reported for doxorubicin. Based on the above results, a combination regimen including THP has been investigated in Japan.