Hypofractionated (2.75 Gy per fraction) versus Conventionally Fractionated Primary Radiotherapy for T2N0M0 Carcinoma of the Glottis

Abstract

Introduction Radiotherapy provides excellent outcome in early stage glottic cancer; however, the optimal radiotherapy dose fractionation remains unknown. Objective To investigate the outcome of patients with T2N0M0 treated with either hypofractionated (HypoFxn) or conventionally fractionated radical (ConFxn) radiotherapy. Methods According to our institutional protocol, patients with T2N0M0 glottic cancer can be treated either with ConfFxn or HypoFxn radiotherapy, as per clinician's and patient's choice, following shared decision making discussing the advantages and disadvantages of both modalities. A total of 77 patients with T2N0M0 squamous cell carcinoma of glottis treated with either HypoFxn 55Gy in 20 fractions (n = 19) or ConFxn 63 to 65Gy in 30 fractions (n = 58) were included. Results With median follow-up of 3.4 years, there was no significant difference in disease-free survival (median: HypoFxn = 65.2 months, and ConFxn = 75.3 months; p = 0.874), local recurrence free survival rates (median: HypoFxn = 78.8 months vs. ConFxn = 81.2 months; p = 0.274), and overall survival (median: HypoFxn = 65.9 months vs. ConFxn = 67.7 months; p = 0.532). Elective neck irradiation was given to 43 patients, all in the ConFxn group, and this was associated with poorer local control (p = 0.027). The use of radiotherapy modality, three-dimensional conformal radiotherapy (3DRT) versus intensity modulated radiotherapy (IMRT), was not a prognostic factor (p = 0.36). In the HypoFxn group, grade III acute dysphagia requiring nasogastric tube was 16%, compared with 25% in the ConFxn group (p = 0.446). Conclusion HypoFxn radiotherapy provides a comparable treatment outcome with acceptable toxicity. The addition of prophylactic irradiation of the neck lymph nodes has no impact on regional control.

Keywords

• t2n0m0
• glottis
• larynx
• radiotherapy
• hypofractionated