Misonidazole and unconventional radiation in advanced squamous cell carcinoma of the esophagus: a phase II study of the Radiation Therapy Oncology Group.

This is a report on Radiation Therapy Oncology Group (RTOG) Protocol No. 78-32, a Phase I/II prospective study aimed at determining tolerance, tumor response, and survival of squamous cell carcinoma of the esophagus treated with unorthodox fractionation radiotherapy combined with misonidazole. Misonidazole was administered by mouth 4 to 6 hr prior to radiation, at a dose of 1.0 to 1.25 Gm/.m2; blood levels were measured at about 4 hr after intake of the drug and reported in micrograms/ml. Radiotherapy was administered at 4 to 6 hr post-misonidazole dose and given with 400 rad fractions, alternating 2 or 3 times/week, up to 4,800 rad. A total of 43 patients were entered; 26 are evaluable for survival at 1 year post accession. Thirty patients (88%) received the planned radiation course. Twenty-eight patients (78%) received the planned misonidazole dosage. Tumor response, evaluable in 18 patients, showed a complete regression (C.R.) in only 2 patients (11%); and partial response (P.R.) in 6 patients (33%). Eight patients (44%) showed no tumor response to planned therapy. Toxicity was acceptable and in 38 evaluable patients only 4 reported (11%) nausea and vomiting, 7 reported mild paresthesias (18%). The median survival was only five months. In 26 patients evaluable for 1 year survival determination, only 1 survived (3.8%) this period. In view of the poor tumor response and low survival observed, we do not recommend that this particular fractionation regimen with misonidazole be used in a Phase III randomized trial in squamous cell carcinoma of the esophagus.

Radiotherapy preceded by multidrug chemotherapy in carcinoma of the esophagus: a pilot study of the Radiation Therapy Oncology Group.

This is a report on R.T.O.G. #77-07, a phase II pilot study aimed at determining the toxicity, primary tumor control, and survival achieved with a combination of triple-drug chemotherapy prior to radiotherapy in carcinoma of the esophagus. The drugs used were vincristine, bleomycin, and methotrexate. A total of 26 cases were registered, one of which died during chemotherapy; 11 had only one chemotherapy course, and 14 had two chemotherapy courses as planned. Drug toxicity could be evaluated in 23 patients: one died from liver damage secondary to chemotherapy effect (4%), two had nausea and vomiting (9%), one had weakness and skin rash (4%), and one had fever and vomiting (4%). There was no complete tumor response to chemotherapy in 22 evaluable cases; 12 of 22 (55%) showed some measurable tumor reduction. Radiation toxicity could be evaluated in 25 patients: 1 of 25 (4%) developed clinical pericarditis, and 2 of 25 (8%) developed severe esophagitis. A complete response to radiotherapy was observed in 15 of 25 (60%) patients; 7 of 25 (28%) showed a partial response; and 3 of 25 (12%) had no measurable tumor reduction. The median survival in 25 evaluable cases was 22 months. In 11 patients who received a single course of chemotherapy, the median survival was 19 months, while in 14 patients who received two courses of chemotherapy, the median survival was only 9 months. However, this difference is not statistically significant.