Predictors of local failure in early laryngeal cancer.

The aim of the study was to assess the impact of factors that could predict the probability of local failure in early laryngeal squamous cell carcinoma treated with curative radiotherapy. Sixty seven patients (12 women and 55 men) with laryngeal cancer stage I (47 patients) and stage II (20 patients) were treated from 1998 to 2003 with curative radiotherapy and retrospectively evaluated. Median follow-up was 36 months (3-80). Local relapse occured in 10 patients (15%), regional lymphnodes relapse affected 2 patients. The median time between start of radiotherapy to recurrence was 13 months (3-48). Death due to cancer occured in 4 patients (2 died from locoregional progression of the recurrence and 2 from distant metastases), whereas 7 patients died from non-cancer related causes. The 2-year overall survival rate was 90% and 5-year OS was 79%. The 2-year local control rate was 82% and 5-year local control was 79%. In the univariate analysis there was a statistically significant decrease in local control influenced by grading (p<0.0001). High risk group of relapse encompassed patients with at least two negative factors: supraglottic tumor, women, radiotherapy prolongation by 3 or more days and high grade tumor and has 3 times worse local control than low risk group (p=0.0125). The highest risk of local reccurrence was in the first three years after radiotherapy than later (p=0.0057). On multivariate analysis unfavourable prognostic factors for local control were gender (p=0.022), presence of 2 or more negative risk factors (p=0.018) and lengths of follow up (p=0.005). Radiation dose, stage, age, hemoglobin level and anterior commissure involvement were not significant factors for local control. Overall survival was affected both in the univariate and multivariate analysis by presence of local relapse (p<0.005) and follow up duration (p<0.02). Anemia had borderline significance for overall survival in univariate analysis (p=0.064), but in the multivariate analysis was significant unfavourable factor (p=0.008). Other studied factors (radiation dose, anterior commissure involvement and age) were not reaching level of statistical significant value for overall survival. Close follow up strategy is recommended for high risk group of patients with two or more risk factors especially in the first three years after radiation therapy.