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.

Actinomycin D is generally administered by serial low-dose injection over 5-10 days. Recent recognition of prolonged serum and tissue half-lives suggests that high-dose intermittent injecton should be equally effective and less toxic. An intermitten single dose schedule was selected for this phase II trial of actinomycin D in 23 patients with advanced breast cancer refractory to standard combination chemotherapy. The drug was given in doses of 0.75-1.5 mg/m2 at 2-week intervals or on days 1 and 8 of 28-day treatment cycles. One patient obtained a partial response with a duration of 5.7 months. Four patients experienced stabilization of advanced disease, with a mean duration of response of 6.4 months. Gastrointestinal toxicity occurred in 47% of patients and mild to moderate myelosuppression in 39%. We conclude that actinomycin D in this dosage and schedule has limited activity in advanced breast cancer. Higher doses might result in increased response rates but would be associated with greater toxicity.

We present two cases of reactivation of Hand-Schüller-Christian disease or multifocal eosinophilic granuloma 6 and 13 years after discontinuation of systemic therapy. Both patients received oral therapy with methotrexate and prednisone continuing for 2--3 years after the disease was thought to be in remission. Relapses were detected because of disease symptoms and treated with surgery with or without radiation. Neither patient has required reinstitution of systemic therapy. These cases are cited as evidence of the chronicity of the disorder and as a reminder that reactivation is possible after years of disease inactivity. Therefore, long-term clinical follow-up of patients in remission is indicated.