A phase II study of concomitant chemoradiotherapy for laryngeal carcinoma using carboplatin

We conducted a phase II study of concomitant chemoradiotherapy with carboplatin for laryngeal carcinoma.

Sixty-four patients with stage II-IV (stage II, 36; III, 19; IV 9) laryngeal carcinoma were treated with concomitant administration of carboplatin (CBDCA) during radiotherapy (CRT group) between 1991 and 1994. There were 36 supraglottic, 25 glottic, and 3 subglottic carcinomas. Patients with stage II and stage III-IV received intravenous CBDCA of 100 mg/m2 and 120 mg/m2 once a week, respectively. Tumor response was assessed at 40 Gy in 16 fractions to select the patients suitable for total laryngectomy or radical radiotherapy of 65 Gy in 26 fractions in 6.5 weeks. The treatment results were compared with the historical control consisting of 56 patients consecutively treated from 1988 to 1990 without chemotherapy (RT group). The two studies were comparable with regard to patient characteristics, including age distribution, gender, tumor location, size, and clinical stage.

The actuarial 5-year survival rate was 80.3% for the CRT group and 81.3% for the RT group. A favorable response (complete response or partial response) at 40 Gy was observed in 87.5% of the patients of the CRT group and in 62.5% of the patients of the RT group (chi2 = 7.566, p < 0.01). The actuarial 5-year larynx preservation rate for the CRT group (75%) was significantly higher than that for the RT group (57%) in patients with T2 supraglottic carcinoma (p < 0.05). There was no difference in the larynx preservation rate between the two treatment arms for any T stage of glottic carcinomas.

CRT using carboplatin improved the tumor response at 40 Gy and consequently achieved a higher larynx preservation rate for T2 supraglottic carcinoma. A clinical randomized trial is indicated to certify the findings of this phase II study.