PURPOSE: The aims of the present study were to explore pre-treatment predictors of weight loss during radiation treatment only in head and neck cancer (HNSCC) patients and investigate the weight loss in patients with or without a feeding tube.

METHODS: Retrospectively, weight change during curative radiotherapy was investigated in 476 consecutive HNSCC patients. Independent predictors were identified using multivariate regression analysis with weight loss below or above 5 % as the primary dependent variable.

RESULTS: Baseline BMI, tumor site, and stage predicted weight loss above 5 %. The odds of weight loss above 5 % in patients with BMI >25 were 3.00 ± 0.64 times higher compared with patients with BMI <25 (p < 0.0001). Patients with pharyngeal, oral cavity, or supraglottic tumors had 3.12 ± 0.80 times higher odds of weight loss above 5 % compared with glottic cancer patients (p < 0.0001), and the odds were 1.68 ± 0.40 times higher in stage III-IV patients compared with stage I-II patients (p = 0.03). Seperate analyses revealed that tumor site and stage only predicted weight loss in patients with BMI >25 but not in patients with BMI <25. Patients receiving a feeding tube weighed less than patients without (73.8 vs 78.3 kg) and feeding tube reduced, but did not prevent, weight loss which averaged 6.7 ± 4.7 kg (7.4 ± 4.7 %) compared with 4.7 ± 5.9 kg (5.5 ± 6.0 %) in patients without a feeding tube (P < 0.0001).

CONCLUSION: Pre-treatment BMI, tumor site and stage predicted weight loss above 5 % in HNSCC patients during radiotherapy. BMI should be considered when analyzing weight loss in HNSCC patients receiving curative radiotherapy.