Stage I (T1 N0 M0) squamous cell carcinoma of the laryngeal glottis: therapeutic results and voice preservation.

BACKGROUND: The therapeutic outcomes for voice preservation in Stage I (T1 N0 M0) glottic carcinoma, treated with conservation surgery, radiation therapy, and endoscopic resection, are controversial.
METHODS: A retrospective tumor registry retrieval of data on patients treated with curative intent at Washington University Medical Center-Barnes Hospital between January 1971 and December 1990 for the surgical group, January 1971 to December 1985 for the low-dose radiation group, and January 1986 to January 1995 for the high-dose radiation group, was performed.
RESULTS: The 659 patients with Stage I (T1 N0 M0) glottic carcinoma treated with curative intent were subdivided into four groups: (1) 90 patients received low-dose radiation (mean dose 58 Gy, range 55-65 Gy, daily fractionation 1.5-1.8 Gy); (2) 104 patients received high-dose radiation (mean dose 66.5 Gy, range 65-70 Gy, daily fractionation 2-2.25 Gy); (3) 404 patients underwent conservation surgery; and (4) 61 patients had endoscopic resection. T1A (85%) and T1B (15%) disease was equally distributed among the groups. The anterior commissure was involved in 38 patients in the radiation therapy groups and 56 patients in the surgical groups. The overall local control was 89%. The overall local salvage was 84%. The overall unaided laryngeal voice preservation was 90%. The overall 5-year disease specific and actuarial survival rates were 95% and 81%, respectively. Prevalence of 2% regional metastases, 1.2% distant metastases, and 14% second primary malignancies were documented. The cure rate was 69% for regional metastases, 13% for distant metastases, and 44% for second primary malignancies. There were 5 complication deaths (0.1%), and 38 (6%) patients died of intercurrent disease. The use and dose of tobacco products was significantly increased in patients who died of intercurrent disease (p = 0.004) or developed second primary malignancies (p = 0.024). No significant difference was observed among the four therapeutic groups in the 5-year cause-specific survival rate (p, 0.68). Actuarial survival was significantly decreased in the low-dose radiation therapy group as compared with the other three therapeutic groups (p = 0.04). Initial local control was poorer for the endoscopic (77%) and low-dose radiation (78%) groups as compared with the high-dose radiation (89%) and conservation surgery (92%) groups (p = 0.02) but significant differences were not found for ultimate local control following salvage treatment. Unaided laryngeal voice preservation was similar for high-dose radiation (89%), conservation surgery (93%) and endoscopic resection (90%), but significantly poorer for low-dose radiation (80%; p = 0.02). T1B disease (N = 94) had similar local control and voice preservation with conservation surgery (87%) and high-dose radiation (88%) but lower results with low-dose radiation and endoscopic resections (67% unaided laryngeal voice preservation; p = 0.02).
CONCLUSION: (1)The four therapeutic groups achieved similar rates of disease specific survival and ultimate local control. (2) Low-dose radiation was associated with significantly lower overall actuarial survival and unaided laryngeal voice preservation. (3) Endoscopic resection was associated with a significantly lower initial local control rate, but following salvage therapy achieved equivalent results to the other treatment methods. (4) Patients with (T1 N0 M0) glottic carcinoma had similar survival, local control, and unaided laryngeal voice preservation rates with high-dose radiation, conservation surgery, and endoscopic resections, but not with low-dose radiation therapy. (c) 1999 John Wiley & Sons, Inc. Head Neck 21: 707-717, 1999.