Post-operative radiotherapy in advanced laryngeal cancer: effect on local and regional recurrence, distant metastases and second primaries.

This was a retrospective study of patients who did or did not receive post-operative radiotherapy for squamous cell carcinoma of the larynx.The rates of local and regional recurrences, distant metastases and second primaries were evaluated in 236 patients who received radiotherapy following surgery. These rates were evaluated and compared with those from 294 patients treated with surgery alone. Multivariate analysis of irradiated patients revealed that local and regional recurrences were determined independently by tumour (T) and pathologic node (pN) stages (p < 0.05). The distant metastasis rate significantly depended on N stage (p < 0.05). Multiple primary tumours were not significantly affected by any of the factors studied (p > 0.05). Analysis of both irradiated and non-irradiated patients revealed that local and regional recurrence was determined independently by pathologic T (pT) stage, tumour localization, radiation status and pN stages (p < 0.05). The distant metastasis rate significantly depended on N stage and tumour localization (p < 0.05) and the rate of formation of multiple primary tumours was significantly affected by the patient's age and radiation status (p < 0.05). In conclusion irradiation of laryngeal cancer patients independently increases the risk of local and regional recurrence, and also increases the risk of multiple primary tumours while not significantly influencing the risk of distant metastasis. The risk of distant metastasis is affected by determinants of advanced lesions and tumour localization.