Purpose: To test for a possible correlation between high-grade acute organ toxicity during primary radio(chemo)therapy and treatment outcome in patients with locally advanced head and neck squamous cell carcinoma (HNSCC).
Patients and methods: From 05/1994 to 01/2009, 216 HNSCC patients were treated with radio(chemo)therapy in primary approach. They received normofractionated (2 Gy/fraction) irradiation including associated nodal drainage sites to a cumulative dose of 70 Gy. 151 patients received additional concomitant chemotherapy (111 patients 5-fluorouracil/mitomycin C, 40 patients cisplatin-based). Toxicity during treatment was monitored weekly according to the Common Toxicity Criteria (CTC), and any toxicity grade CTC >or= 3 of mucositis, dysphagia or skin reaction was assessed as high-grade acute organ toxicity for later analysis.
Results: A statistically significant coherency between high-grade acute organ toxicity and overall survival as well as locoregional control was found: patients with CTC >or= 3 acute organ toxicity had a 5-year overall survival rate of 44% compared to 8% in patients without (p < 0.01). Thereby, multivariate analyses revealed that the correlation was independent of other possible prognostic factors or factors that may influence treatment toxicity, especially concomitant chemotherapy and radiotherapy technique or treatment-planning procedure.
Conclusion: These data indicate that normal tissue and tumor tissue may behave similarly with respect to treatment response, as high-grade acute organ toxicity during radio(chemo)therapy showed to be an independent prognostic marker in the own patient population. However, the authors are aware of the fact that a multivariate analysis in a retrospective study generally has statistical limitations. Therefore, their hypothesis should be further analyzed on biomolecular and clinical levels and other tumor entities in prospective trials.