Clinical trial of pyridoxine to reduce vincristine neurotoxicity.

In a murine model system, pyridoxine has demonstrated protective properties during administration of lethal doses of vincristine (VCR). Subsequently, pyridoxine has been evaluated in patients receiving VCR during an adjuvant chemotherapy program for stage II carcinoma of the breast. The toxicities, cumulative VCR dosage, and percentage of ideal dosage observed in 24 patients receiving pyridoxine have been compared to those observed in 88 patients who previously received VCR without pyridoxine in the same chemotherapy program. All patients ideally were to receive VCR 1.0 mg/m2 weekly for 6-weeks with dose modification for neurotoxicity. Treatment patients received pyridoxine 1.5 grams p.o. daily in three divided doses during the 6-week course. The degree of neurotoxic manifestations of VCR was similar in the treatment and comparison patients. Absent to mild neurotoxicity was observed in approximately 70% of patients in both groups; moderate or greater neurotoxicity occurred in about 30% of patients in both groups. Full dosage (6.0 mg/m2) was attained in 8 (33%) treatment patients and 18 (24%) comparison patients (p = 0.28). The mean percentage of ideal dosage of VCR was 84.6 +/- 10.8 in patients receiving pyridoxine and 81.9 +/- 21.6 in those given only VCR (p = 0.59). Gastrointestinal and hematologic toxicities were similar in both groups. Pyridoxine in this dose and schedule afforded no protection from the neurotoxic side effects of VCR.

Sequential hemibody and local irradiation with combination chemotherapy for small cell lung carcinoma: a preliminary analysis.

Sequential hemibody irradiation (SHB) was integrated with combination chemotherapy and local irradiation (LRT) in the induction and consolidation phases of a therapeutic protocol for small cell lung carcinoma (SCLC). Forty-one previously untreated patients were entered into this program. Among 38 evaluable patients (20 with limited disease [LD] and 18 with extensive disease [ED], the overall response rate was 63% (90% in LD and 33% in ED patients). The estimated overall survival is 8.1 months. The major toxicity has been myelosuppression--especially thrombocytopenia. The frequency of previously described "acute radiation syndromes" and radiation pneumonitis associated with hemibody irradiation have been substantially decreased at the current dosage with premedication and shielding techniques. The integration of SHB as a systemic therapy with combination chemotherapy and LRT is a feasible program for sequential administration of non-cross-resistant agents in SCLC and may be beneficial in patients with limited disease.

VP-16-213 in combination chemotherapy with chest irradiation for small-cell lung cancer: a randomized trial of the Piedmont Oncology Association.

The role of etoposide epipodophyllotoxin (VP-16-213) in a combined modality treatment program incorporating local chest irradiation and combination chemotherapy with cyclophosphamide, Adriamycin (Adria Laboratories, Columbus, Ohio), and vincristine has been evaluated in a randomized trial of 165 patients with small-cell lung cancer. The overall response rate (complete response [CR] plus partial response [PR]) was significantly greater in the VP-16-213 arm (85% v 64%, P = .005) primarily as a consequence of improved response in patients with extensive disease (85% v 38%, P = .002 and 30% v 8% for CR only, P = .045). No differences in the response rates were observed in limited disease. The duration of response (months) was greater in the VP-16-213 arm (8.6 v 7.0 overall and 14.4 v 11.5 for CR) but not significantly so. Median survival times (months) were consistently greater in the group receiving VP-16-213 when analyzed according to extent of disease and response (10.6 v 9.5 overall; 15.0 v 13.6 for limited disease; 9.0 v 6.7 for extensive disease; 18.5 v 16.2 for CR overall; and 18.6 v 16.1 for CR in limited disease); the results were not statistically significant. The median survival of extensive disease patients attaining a CR was 15.3 months (range 3.2 to 34.3 + months) in the VP-16-213 arm and 7.4+ and 8.1+ months for the two patients with CR in the other group. Anemia and leukopenia occurred to a greater degree in the four-drug regimen, but no unusual or significant compounding toxicity (ie, neurotoxicity) was observed otherwise. Further investigation of this agent in combination chemotherapy programs for small-cell lung cancer appears to be warranted.

High-dose cyclophosphamide and 5-fluorouracil versus vincristine, doxorubicin, and cyclophosphamide in advanced carcinoma of the breast. A phase III study of the Piedmont Oncology Association (POA).

Forty-nine patients with advanced carcinoma of the breast who had received no prior chemotherapy were randomized to receive either high-dose cyclophosphamide (C) 1250 mg/M2 intravenously on day 1 and 5-fluorouracil (F) 600 mg/M2 intravenously on days 1 through 5 (CF), or vincristine (V) 1.5 mg/M2, doxorubicin (A) 50 mg/M2 and cyclophosphamide (C) 500 mg/M2 (VAC), all intravenously on day 1. Both regimens were repeated at 3-week intervals. Nine of 25 patients (36%) treated with CF and ten of 21 patients (48%) treated with VAC showed a complete or partial response as defined by the (UICC) guidelines. The estimated median time to progression for all patients was 3.5 months for CF and 6.0 months for VAC, with the median time to progression for responding patients being 8.5 months on CF and 6.3 months on VAC. Estimated survival is also similar for the two regimens. Ten of the patients treated with high-dose CF experienced septic episodes and four died. Toxicity on the CF arm necessitated premature closure of the study, and thus full statistical comparison of the efficacy of the two regimens cannot be made.

Treatment of advanced non-Hodgkin's lymphoma with vincristine infusion.

Twenty-five patients with a variety of histologic types of advanced non-Hodgkin's lymphoma refractory to previous chemotherapy were entered into a trial of vincristine infusion. Patients received 5-day courses of vincristine 0.25 mg/m2/day by continuous intravenous infusion after an initial 0.5 mg intravenous bolus injection. Courses were repeated every 3 weeks. Objective responses were observed in nine patients (36%), all of whom had previously received vincristine given by conventional bolus injection. A complete response occurred in a patient with diffuse mixed histiocytic lymphocytic lymphoma, and partial responses were observed in eight patients with the following histologic types: diffuse poorly differentiated lymphocytic (4); nodular poorly differentiated lymphocytic (2); diffuse mixed histiocytic lymphocytic (1); and diffuse histiocytic (1). Duration of response lasted from 1.2 to 16.2 months (mean, 4.4 months). The principal complication of therapy was mild-to-moderate neurotoxicity; this occurred in 12 patients (48%) who received a total of 54 courses of vincristine infusion. Hematologic toxicity was minimal and nausea/vomiting did not occur. Vincristine infusion may afford palliation for patients with advanced non-Hodgkin's lymphomas who have become refractory to standard chemotherapeutic regimens even if they have received prior vincristine by conventional bolus injection. These data suggest the possibility of enhancing the therapeutic efficacy of vincristine in the treatment of non-Hodgkin's lymphoma by use of an infusion technique.

Treatment of poor risk acute leukemia with sequential high-dose ARA-C and asparaginase.

Resistance of leukemia cells to cytosine arabinoside (ARA-C) may be due to any one or combination of biochemical processes, which in certain instances may be substantially reversed by an appropriate increase in ARA-C dosage. Based on these and other laboratory observations indicating pharmacologic synergy between sequential high-dose ARA-C and asparaginase (HiDAC----ASNase), a therapeutic program was developed for the treatment of patients with acute nonlymphocytic leukemia (ANLL) refractory to conventional doses of ARA-C, as well as patients with high risk ANLL and advanced acute lymphocytic leukemia (ALL). Treatment consisted of 3-hr intravenous infusions of 3 g/sq m of ARA-C given at 12-hr intervals for 4 doses, followed by 6,000 IU/sq m ASNase given i.m. at hour 42. The same schedule was repeated on day 8. In 32 induction attempts, only 4 patients proved to be truly refractory, i.e., failed to achieve substantial leukemia cell cytoreduction. Complete remissions were achieved with HiDAC---- ASNase in 9 of 13 patients with refractory ANLL, 6 of 9 patients with antecedent hematologic disorders, and 3 of 10 patients with advanced ALL. These include 9 of 14 patients who had either failed induction or who had relapsed on active ARA-C therapy and 6 of 8 patients who had had no prior exposure to ARA-C. The median duration of unmaintained remission in ANLL was 5 mo. In a patient with central nervous system (CNS) leukemia, there was clearance of cerebral spinal fluid (CSF) blasts without intrathecal therapy, suggesting a role for HiDAC in CNS prophylaxis. In general, toxicity was tolerable and reversible. These data suggest that HiDAC----ASNase is an exceptionally effective and well tolerated regimen in leukemic patients with antecedent hematologic disorders and in those refractory to conventional doses of ARA-C.

Vincristine by continuous infusion in refractory breast cancer: a phase II study.

Eighteen patients with advanced refractory breast carcinoma were treated with vincristine (VCR), 0.5 mg I.V. bolus followed by continuous I.V. infusions of 0.25 mg/m2/day for 5 days every 3 weeks. The daily dose of VCR was infused in 1000 ml D5W to which was added hydrocortisone 50 mg and heparin 3000 U. Patients received from one to six courses (mean 2.3 courses). No objective responses were observed. Stable disease was noted in five patients who had skeletal metastases only. Disease progression occurred in the remaining 13 patients, 10 of whom had received prior VCR by bolus injection. The principal toxicity consisted of constipation without ileus and hyporeflexia-paresthesias. Vincristine, administered by continuous I.V. infusion according to this dose and schedule does not appear to be effective in the treatment of patients with advanced refractory breast cancer.