Efficacy and Toxicity of Gemcitabine Plus Docetaxel Combination as a Second Line Therapy for Patients with Advanced Stage Soft Tissue Sarcoma

Few chemotherapy agents are active in leiomyosarcoma (LMS), particularly LMS that has progressed after doxorubicin treatment. We sought to determine the response to gemcitabine plus docetaxel among patients with LMS. Patients with unresectable LMS of uterine (n = 29) or other (n = 5) primary sites who did not respond to zero to two prior chemotherapy regimens were enrolled onto a phase II study of gemcitabine 900 mg/m(2) intravenously (i.v.) on days 1 and 8 plus docetaxel 100 mg/m(2) i.v. on day 8 with granulocyte colony-stimulating factor given subcutaneously on days 9 to 15, delivered every 21 days. Patients with prior pelvic radiation received 25% lower doses of both agents. Gemcitabine was delivered over 30 or 90 minutes in cycles 1 and 2 and by 90-minute infusion in all subsequent cycles. Pharmacokinetic studies assessed in vivo differences in gemcitabine concentrations with different rates of infusion. Thirty-four patients (median age, 55 years; range, 32 to 74 years) have enrolled. Fourteen had received prior pelvic radiation. Sixteen of 34 patients had progressed after doxorubicin-based therapy; 18 had no prior chemotherapy. Among 34 patients, complete response was observed in three patients and partial response in 15, for an overall response rate of 53% (95% confidence interval, 35% to 70%). Seven patients had stable disease. Fifty percent of patients previously treated with doxorubicin responded. Hematologic toxicity was common (neutropenia: grade 3, 15%; grade 4, 6%; thrombocytopenia: grade 3, 26%; grade 4, 3%), but neutropenic fever (6%) and bleeding events (0%) were rare. The median time to progression was 5.6 months (range, 4 to 10 months). Gemcitabine plus docetaxel is tolerable and highly active in treated and untreated patients with LMS.

The aim of this trial was to compare the activity and toxicity of single-agent doxorubicin with that of two multidrug regimens in the treatment of patients with adult advanced soft tissue sarcomas. This was a prospective randomized phase III trial performed by 35 cancer centers within the Soft Tissue and Bone Sarcoma Group of the European Organization for Research and Treatment of Cancer (EORTC). Six hundred sixty-three eligible patients were randomly allocated to receive either doxorubicin 75 mg/m2 (arm A), cyclophosphamide, vincristine, doxorubicin, and dacarbazine (CYVADIC) (arm B), or ifosfamide 5 g/m2 plus doxorubicin 50 mg/m2 (arm C). The overall response rate was 24% (95% confidence interval, 20.7% to 27.3%) among eligible patients and 26% among assessable patients. No statistically significant difference was detected among the three study arms in terms of response rate (arm A, 23.3%; arm B, 28.4%; and arm C, 28.1%), remission duration (median, 46 weeks on arm A, 48 weeks on arm B, and 44 weeks on arm C), or overall survival (median, 52 weeks on arm A, 51 weeks on arm B, and 55 weeks on arm C). The degree of myelosuppression was significantly greater for the combination of ifosfamide and doxorubicin than for the other two regimens. Cardiotoxicity was also more frequent in this arm, but other toxicities were similar. In advanced soft tissue sarcomas of adults, single-agent doxorubicin is still the standard chemotherapy against which more intensive or new drug treatments should be compared. Combination chemotherapy cannot be recommended outside a controlled clinical trial with the exclusion of some subsets of sarcoma patients for whom significant tumor volume reduction may be an important end point of a chemotherapy regimen.

This three-armed phase III study in adults with advanced soft tissue sarcomas was planned as a comparison of objective regression rates, toxicity, and survival of patients receiving doxorubicin alone, ifosfamide plus doxorubicin, and mitomycin plus doxorubicin plus cisplatin. Between December 1987 and July 1990, 279 patients with histologically confirmed sarcomas were enrolled to receive treatment A (doxorubicin 80 mg/m2), treatment B (ifosfamide 7.5 g/m2 plus doxorubicin 60 mg/m2), or treatment C (mitomycin 8 mg/m2 plus doxorubicin 40 mg/m2 plus cisplatin 60 mg/m2). Of 262 assessable patients, 74 (29%) achieved objective tumor regression. Objective regression occurred in 20% of the 90 patients who received doxorubicin alone (complete remission [CR] rate, 2%), in 34% of the 88 who received ifosfamide plus doxorubicin (CR rate, 3%), and in 32% of the 84 who received mitomycin plus doxorubicin plus cisplatin (CR rate, 7%). With grade 3 or greater myelosuppression in 53% of group A, 80% of group B, and 55% of group C, regimen B was significantly more myelosuppressive than either regimen A or C (P = .01) with two, three, and one treatment-related deaths, respectively. Synovial sarcomas were responsive to ifosfamide plus doxorubicin, especially among patients younger than 40 years of age. Ifosfamide plus doxorubicin produced a significantly higher regression rate (P = .03) than did doxorubicin alone; however, this was achieved at a level of myelosuppression significantly more intense than that produced by the single agent or by the three-drug combination. Mitomycin, doxorubicin, and cisplatin also appeared to be more active than the single agent; however, at a myelosuppression level similar to that of doxorubicin alone, this trend (P = .07) did not attain the usual level for significance. No significant survival differences were observed.