[Thyroidectomy associated with laryngectomy in laryngeal cancer treatment. Is it routinely necessary?]

In patients with laryngeal invasive epidermoid carcinoma who are candidates for total laryngectomy, it is recommended to resect en bloc at least half of the thyroid gland on the same side as the laryngeal tumor with the objective of decreasing local recurrence associated with thyroid infiltration. Nevertheless, in the histopathologic analysis of the specimen, a minority of thyroid glands show tumor infiltration. The fact that in these patients even partial thyroid resection is associated with hypothyroidism increased by postoperative radiotherapy is well known. The study was undertaken to determine the frequency of thyroid gland invasion in patients who have undergone total laryngectomy due to laryngeal cancer and its associated factors.

We evaluated the histological results of glands resected en bloc with laryngectomy in patients who underwent total laryngectomy due to laryngeal cancer; the clinical stage was compared to the laryngeal subsite tumor origin. The glandular histological condition was compared to the local recurrence presence (peristomal).

Ninety two patients were included, 11 (12%) showed glandular infiltration due to epidermoid carcinoma, all with tumors clinically typified as T3 and T4, 8/11 were transglottic and only 3 (27%) showed subglottic invasion. During follow-up (5-year mean) 17/92 showed peristomal recurrence (18%), only 3 (3%) showed thyroid invasion. Among patients with glandular invasion the peristoma recurrence rate was 27% (3/11).

The best laryngeal cancer thyroid tumor invasion predictor is the evidence of extralaryngeal extension. Thyroid resection en bloc should not be routinely advised due to the low frequency of glandular infiltration.