Taketsugu Ikari

Excision Level and Indication for Contralateral Neck Dissection in Hypopharyngeal Cancer Surgery

Margins of extirpated specimens of hypopharyngeal cancer were examined histopathologically. Residual cancer nest, which is most likely due to directional preponderance of the submucosal lymph flow of the hypopharyngeal cavity, was characteristically demonstrated at the superior margin and in the submucosal layer. We propose that laryngopharyngectomy be done at the extended excision level superiorly at the base of the palatine tonsil and inferiorly at the level of the 2nd thoracic vertebra and with a safety margin of at least 2 cm. The incidence of ipsilateral and contralateral neck metastasis was also histopathologically evaluated from specimens obtained by neck dissection. Contralateral neck metastasis was histopathologically confirmed in more than 30% of the cases examined and showed a difference in incidence related to histological differentiation and T classification. We conclude that bilateral neck dissection is advisable in all cases of hypopharyngeal cancer except for patients with a well-differentiated T2 lesion.

Surgical treatment of laryngotracheal stenosis by a trough technique.

Many methods have been tried and reported in the treatment of laryngotracheal stenosis. Among them, a trough technique seems universal at present. To date, we have tried several methods of this technique, but each method had its own demerits. We used, as a cartilagenous framework, a homograft or tracheal ring cartilages for the last four cases of laryngotracheal stenosis. These tracheal ring cartilages were resected from relatively young patients with laryngeal carcinoma. Total laryngectomy was done just below the level of the fourth tracheal ring, then the fourth tracheal ring was resected and stored in 70% alcohol. The cartilage was used after it was made certain pathologically that there was no invasion of carcinoma at the third tracheal ring level. The operative procedure of this trough technique is as follows. In the first stage, a trough is created at the stenosed region and the trough is maintained by placing a Quick Set Silicone (Q.S.S.) stent mold over it. While waiting for scar formation of the tissues surrounding the trachea, the second stage reconstruction is performed four weeks after the first. The trough is closed with hinged skin flaps on both sides, and the reserved tracheal ring cartilages are sutured every 5 mm onto the outer surface of the hinged skin flaps to make a cartilagenous framework. The neck is closed with advanced neck skin flaps. A more ideal tracheal lumen is created by this technique. Our four patients are doing well two years or more after the operation.

Scintiscanning of mucoepidermoid tumor of the parotid gland.

99mTc-O4 and/or 67Ga-citrate scintigraphies were preoperatively applied to 13 cases of parotid mucoepidermoid tumor. The resected specimens were histopathologically subdivided into three types: well (6 cases), moderately (one case), and poorly differentiated (6 cases). As the other parotid neoplasms except adenolymphoma and oxyphilic adenoma, all poorly differentiated tumors showed focal defect image in 99mTc-O4 scintiscanning (4/4). They indicated a focal hot image in 67Ga-citrate scanning at a high rate (4/6). Otherwise, well differentiated tumors were scarcely pointed out in cold image and were usually indicated as a symmetrical image (5/6) in 99mTc-O4 scanning. None of them showed a focal hot image in 67Ga-citrate scanning, but two cases indicated diffuse increased uptake and another case showed a focal defect image. The clinical prognosis of mucoepidermoid tumors is extremely correlated to the degree of cell differentiation in our prospective study. For that reason, the therapeutic method should be carefully selected in the tumors suspected of low grade malignancy. Our study suggests that RI (99mTc-O4 and 67Ga-citrate) scintigraphy is helpful in evaluating the malignancy grade of mucoepidermoid tumors.