Local-regional control by conventional radiotherapy according to tumor volume in patients with squamous cell carcinoma of the pharyngolarynx

Background: To estimate the effect of tumor volume on local-regional contro l of pharyngolaryngeal cancer by radiotherapy (RT). Methods: Definitive RT for 48 patients with squamous cell carcinoma of the lateral wall of the oropharynx, pyriform sinus and supraglottic larynx was reviewed. Tumor volume was estimated from computed tomography and it was ex pressed as the diameter of a sphere the volume of which is equal to the pri mary tumor (T-d) and sum of the volumes of metastatic adenopathies (N-d) Al l patients received greater than or equal to 60 Gy (median 66 Gy) to the gr oss tumor by conventional fractionation with or without chemotherapy. Results: A median period of follow-up for survivors was 32.7 months (range, 12.4-68.6). The 2 year local control rate for T1/2 (n = 30) and T3/4 (n = 18) patients was 72 and 65%, respectively (P = 0.966), however, the rates f or T-d < 4 cm tumors (n = 37) and T-d greater than or equal to 4 cm tumors (n = 11) were significantly different (80% vs 27%, P< 0.001). The 2 year re gional control rates for N-d < 3 cm lesions (n = 29) and N-d greater than o r equal to 3 cm (n = 19) lesions were 85 and 42%, respectively (P < 0.001). The 2 year ultimate regional control rates for N2/3 disease with N-d < 4 c m (n = 11) and N-d greater than or equal to 4 cm In = 11) were 100 and 42%, respectively (P = 0.004). Conclusions: Conventional radiotherapy may allow organ preservation and ult imate local control in patients with T-d < 4 cm and N-d < 4 cm disease, but larger volume tumors should be considered candidates for the most intensiv e chemoradiotherapy.