Patricia J. Zekan

Amelioration of vincristine neurotoxicity by glutamic acid

Neurotoxicity is the principal limiting side effect of the widely used antitumor agent, vincristine. Following evaluation of glutamic acid as a potential modifier of vincristine toxicity in preclinical studies in mice and a preliminary clinical trial, a prospective, double-blind, placebo-controlled, randomized trial was conducted by the Piedmont Oncology Association. Of 87 patients entered into the study, 84 were evaluable, including 42 patients who were randomly assigned to receive vincristine 1.0 mg/m2 weekly for six doses and 42 patients who were assigned to receive glutamic acid 500 mg orally three times daily plus vincristine. The following neurotoxic signs and symptoms were evaluated before each dose of vincristine: reflex changes, paresthesias, constipation, strength, and mental changes. Loss of the Achilles tendon reflex, an objective parameter, was noted in 19 percent of patients receiving glutamic acid and 42 percent of control subjects (p = 0.03). Development of moderate to severe paresthesias, a subjective parameter, occurred in 19 percent of the glutamic acid group and 36 percent of the placebo group (p = 0.09). Overall moderate neurotoxicity (6 units or more), determined by adding the grade of each neurotoxic parameter for the weekly clinic visit in which maximum neurotoxicity occurred, was observed in 21 percent of patients receiving glutamic acid and 43 percent of those in the control group (p = 0.04). Hematologic and gastrointestinal side effects occurred with similar frequency in the two groups. The administration of glutamic acid has decreased vincristine-induced neurotoxicity without any attendant side effects.

Carcinosarcoma of the colon. Report of a unique case with light and immunohistochemical studies

A unique case of carcinosarcoma of the colon is reported. The tumor invaded the bowel wall deeply, metastasized widely, resisted multi‐agent chemotherapy, and caused the patients death 4 years later. The tumor was composed of adenosquamous carcinoma admixed with sarcoma showing osseous, cartilaginous, and nonspecific spindle‐cell differentiation. Although carcinoembryonic antigen appeared limited to carcinoma cells, cytokeratin immunoreactivity was observed in both carcinoma and sarcoma cells. Like carcinosarcomas at other body sites, the finding of cytokeratin in sarcoma cells supports partial epithelial differentiation in this component, likely retained from carcinoma precursor cells. Cancer 58:1126‐1130, 1986.

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.

Improvement of long-term survival in extensive small-cell lung cancer.

The effect of adding the epipodophyllotoxin etoposide (VP-16-213) to a standard chemotherapy regimen for patients with extensive stage small-cell lung cancer was evaluated during a randomized trial. Chemotherapy consisted of vincristine, doxorubicin, and cyclophosphamide (VAC) alone or with etoposide (EVAC). Of 139 patients enrolled, 136 patients were eligible for study and all but five were evaluable for response. The overall objective response was 46% in the VAC group v 70% in the etoposide-treated group (P = .008) with complete response (CR) rates of 12% v 29%, respectively (P = .030). Although the time to the observation of disease progression was significantly longer in the group of patients receiving etoposide (9.6 v 6.5 months, P = .010), overall survival was similar; this was probably due to administration of other agents including etoposide at the time of VAC failure. However, there were noteworthy differences in long-term (greater than or equal to 2 year) survival. Whereas only four (6%) patients treated with VAC lived 2 years, 11 (16%) of the etoposide-treated group did so (P = .100). Two-year failure-free survival was attained in one (2%) of the VAC patients and eight (11%) of the patients treated with etoposide (P = .034). Long-term survivorship, heretofore usually reported in patients with limited stage disease after a variety of treatments, may be possible with this drug combination in the setting of extensive disease.

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.

Combination chemotherapy (5-fluorouracil, methyl-CCNU, mitomycin C) versus 5-fluorouracil alone for advanced previously untreated colorectal carcinoma. A phase III study of the Piedmont Oncology Association.

One-hundred thirty eligible patients with advanced colorectal carcinoma who had received no prior chemotherapy were randomized to either methyl-CCNU, 70 mg/m2 orally every 6 weeks on day 1, mitomycin C, 10 mg/m2 intravenously every 6 weeks on day 1, and 5-fluorouracil (5-FU), 400 mg/m2 intravenously weekly--(MMF)--or 5-FU, 600 mg/m2 intravenously weekly (5-FU). One hundred twenty-six patients are evaluable for response. Of 62 patients treated with MMF, one (2%) achieved complete remission, and three (5%) attained partial remission. Of 64 patients treated with 5-FU, two (3%) achieved complete remission, and eight (13%) attained partial remission. The median survival for patients receiving MMF was 9.5 months compared with 10.3 months for patients receiving 5-FU. The survival distributions for the two regimens were not significantly different, either unadjusted or adjusted for pretreatment characteristics. Performance status and lactic dehydrogenase (LDH) were both significantly associated with survival. Patients with liver metastases only and normal liver function tests had a median survival of 19.8 months and a 40% response rate. This randomized phase III trial did not show any therapeutic advantage for MMF compared to 5-FU therapy alone in advanced colorectal cancer. In addition, hematologic toxicity was significantly greater with the combination (MMF) regimen.

A phase II trial of peg-L-asparaginase in the treatment of non-hodgkins lymphoma

SummaryA polyethylene glycol conjugate of L-asparaginase (PEGLA) was administered to 21 patients with refractory non-Hodgkins lymphoma. The dose given was 2,000 u/m2 intramuscularly every 2 weeks. Eligibility required at least one prior trial of chemotherapy and ambulatory performance status. At entry, all patients had measurable lesions and documented disease progression. The median age of the patients was 61 years; 18 (86%) were ambulatory with minimal symptoms, 12 patients (57%) had 3 or more prior regimens, and 13 (62%) had stage IV disease. Histologic subtype was low grade in 11 patients (52%), intermediate in 7 (33%), high grade in 2 (10%) and unclassifiable in one (5%). There were two partial responses (11%) noted (95% confidence interval of response of 1–30%). Eleven patients (52%) were removed from study due to disease progression. Nine patients (43%), required removal for toxicity (7 for protracted nausea and vomiting and 2 for confusion). One patient died of sepsis while on study but this was not considered drug related. Almost one third of patients complained of fatigue or loss of appetite. Nausea and vomiting occurred in approximately half the patients and was moderate to severe in 9. Diarrhea and abdominal pain were also noted in onethird of those treated. Changes in the partial thromboplastin time and fibrinogen were noted in most patients but resulted in no bleeding complications. In this trial, PEGLA displayed modest activity in a heterogenous group of patients with progressive non-Hodgkins lymphoma.

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.

Recombinant gamma interferon in advanced breast cancer: A phase II trial

Fifteen patients with advanced carcinoma of the breast who had failed prior chemotherapy, were treated with recombinant gamma interferon at a dose of 2mg/m2 (1mg = 2.4 × 107 international units) intravenously for five consecutive days every other week. The median patient age was 51 and all patients had a performance status of 0–2 (Karnofsky ≥ 50). Thirteen patients had two or three sites of metastatic disease and seven were estrogen receptor positive. No complete or partial responses were noted. Although some patients had brief periods of stable disease, almost all patients progressed after one or two courses. Only one patient was able to receive six courses of induction therapy and a brief course of maintenance. Flu-like symptoms and nausea were seen in all patients; vomiting and anorexia were frequent. Hepatic toxicity manifested by enzyme elevation was common and was most severe in patients with liver metastases. In this study a highly purified biologically active gamma interferon was not associated with anti-tumor activity in previously treated women with metastatic breast cancer.

Vinblastine Infusion in Non-Hodgkin's Lymphomas: Lack of Total Cross-Resistance with Vincristine

Historically, vinblastine given by intravenous bolus injection has not been an effective treatment for non-Hodgkins lymphomas; vincristine has displayed greater activity. Also, vinblastine has generally been considered to be cross-resistant with vincristine in such patients. In an attempt to overcome these obstacles, a protracted infusion of vinblastine was administered (0.5-1.5 mg/m2 per day for 5 days) and repeated every 3 weeks. Partial responses were observed in 4 of 29 (14%) patients with a variety of non-Hodgkins lymphoma lasting 2.4, 2.4, 5.5, and 9.0 months. Just prior to treatment the responding patients had received and eventually become refractory to vincristine. These data show a lack of total cross-resistance between vinblastine and vincristine which might have important therapeutic implications in this disease.