BACKGROUND: To evaluate the prognostic value of the cartilage invasion (thyroid, cricoid) in laryngeal cancer, in relation to disease free survival period. METHOD: Examination was made of the charts of 102 patients with cancer of the larynx treated at the INCA/MS-RJ Cancer Hospital between 1992 and 1994. These patients were divided into 4 groups: those having T3N0M0 stage III tumors (excluding patients with T3N1M0); those having T4N0M0 (with tumoral invasion of laryngeal cartilage without extralaryngeal spread); those having T4N0M0 (with neoplastic spread through the laryngeal compartment); and those having metastatic cervical lymphadenopathy (T3N2-3/T4N1-2-3). Survival rate curves were drawn for each group and the survival rate differences between the groups were compared using the Kaplan-Meier method. The value of statistical significance were calculated using the Wilcoxon-Gehan method. RESULTS: Those patients who presented with tumoral invasion of laryngeal cartilage without neoplastic spread, behaved like those with T3N0M0 tumors, with no statistical survival rate difference (p=0.36). Patients who had neoplastic invasion of the laryngeal cartilage (T4N0M0) had a better prognostic than those with extra laryngeal neoplastic spread (T4N0M0) (p=0.02). The presence of metastatic lymph nodes was the main adverse factor affecting prognosis (p=0.002). CONCLUSION: The findings of this study call into question the validity of the present TNM classification in the staging of T4N0M0 laryngeal tumors. New studies, based on a larger number of cases, are needed to corroborate our results.
Laryngeal neoplasms; Laryngectomy; Cricoid cartilage; Thyroid cartilage; Prognosis
