THE SURGICAL-MANAGEMENT OF LARYNGOTRACHEAL INVASION BY WELL-DIFFERENTIATED PAPILLARY THYROID-CARCINOMA

Objectives: To determine prognostic factors for survival in patients w ith invasive well-differentiated thyroid carcinoma, specifically exami ning laryngotracheal invasion as an independent prognostic factor, and to compare types of surgical resection to determine treatment efficac y. Design: Retrospective review of patients with papillary invasive we ll-differentiated thyroid carcinoma surgically treated over 45 years. Setting: Academic tertiary care medical center. Patients: A total of 2 92 patients with invasive well-differentiated thyroid carcinoma were s urgically treated between 1940 and 1995. Informed consent was obtained from all patients. Extent and location of tumor invasion were determi ned. Invasion of larynx and/or trachea occurred in 124 patients (41%). Patterns of invasion and techniques of surgical resection were evalua ted. Intervention: Types of surgical resection performed: complete tum or removal (n=34), ''shave'' excision (n=75), and incomplete tumor exc ision (n=15). Main Outcome Measures: Cox regression analysis was used to determine significance of prognostic factors for survival; Kaplan-M eier curves were used to evaluate survival. A P value of less than .05 was statistically significant. Results: Patterns of invasion by thyro id carcinoma included direct spread through laryngeal framework into p araglottic space or spread from involved lymph nodes. Laryngotracheal invasion was a significant, independent, prognostic factor for surviva l (P<.05). Significance was reached when types of resection were compa red for all patients (P<.05) as well as for those with laryngotracheal invasion alone (P<.001). Conclusions: Laryngotracheal invasion was a significant independent prognostic factor for survival (P<.05). When t ypes of surgical resection were compared, the survival rates of patien ts who underwent shave excision were not different from those of patie nts who underwent radical tumor resection if gross tumor did nor remai n (P>.05). Tumors with minimal invasion may be treated by shaving tumo r from the aerodigestive tract. Gross intraluminal involvement should be resected completely to prevent complications.