Twenty-eight patients with advanced squamous cell carcinomas and adenocarcinomas of the head and neck were treated with dianhydrogalactitol at a dose of 25 mg/m2 iv on each of 5 consecutive days monthly. All patients except one had received previous surgical and/or radiotherapeutic treatments and 12 had received previous chemotherapy. Disease progression (or symptomatic deterioration) occurred in nine patients after the initial course and in eight others after two courses. In 11 patients, the disease remained stable during at least three courses; however, no instances of objective regression of disease were observed during treatment with dianhydrogalactitol despite significant toxic effects in most patients.