Purpose: The purpose of this study was to establish general guidelines for the treatment of patients with early glottic cancer(T1-2N0M0), by assessing the role of primary radiation therapy and by analyzing the tumor-related and treatment-related factors that influence treatment results. We also studied the results of hypofractionated radiation therapy for early glottic cancer.
Material and Methods: This retrospective study comprised 48 patients who suffered from early glottic cancer and were treated by primary radiotherapy at Inha University Hospital, between May 1997 and October 2004. T-stage distribution showed 38 patients as T1 and 10 patients as stage T2. Thirty-eight patients underwent hypofractionated radiotherapy using a 6 MY photon beam, a total tumor dose of 63Gy, in 5 weekly fractions of 2.25Gy, with an overall radiation treatment time of 38 days. Ten patients in the T2 stage tolerated a total dose of 63-72 Gy(median 68.4Gy) in 5 weekly fractions of 1.8-2.0Gy, with an overall radiation treatment time of 40-87 days(median 51 days). All patients were followed up for at least 3 years. Univariate and multivariate analyses were performed to identify the prognostic factors affecting the treatment results.
Result: The 5-year survival rate was 92% for all patients, 94% for T1 patients and 91% for T2 patients. The local control rate was 93.5% for all patients, 95% for T1 and 92.2% for T2 patients. Three patients suffered a relapse following radiotherapy, and underwent subsequent salvage surgery. We included T-stage, tumor location, total radiation dose, field size and overall radiation treatment time as potential prognostic factors. Only T-stage was found to be statistically significant in the univariate analysis, but in the multivariate analysis, it was not found to be significant.
Conclusion: High curative and voice preservation rates were obtained with hypofractionated radiotherapy. Further study with a larger number of patients is needed to determine the prognostic factors affecting treatment results.
|