[Excisional surgery of hypopharyngeal cancer and primary reconstruction of the defect]

A combination of total laryngopharyngectomy and primary reconstruction of the cervical esophagus is the operation of choice in the treatment of advanced hypopharyngeal cancer. For the excision, the most important task for the surgeon is to estimate the adequate safety margins superiorly and inferiorly. In order to ensure safer margins, animal experiments on lymph-flow in the submucosal layer of the hypopharyngeal cavity that is considered to be responsible for invisible submucosal invasion of cancer, were undertaken. Based on the results of both these experiments and clinical observations of many cases, it appeared most likely that cancers in the pyriform sinus or in the posterior wall tend to spread upward to the oropharyngeal cavity, while those in the postcricoid region have a tendency to invade in every direction but mainly downward to the cervical esophagus. In many cases, therefore, the cavity should be excised at a level just inferior to the palatine tonsil with a safety margin of more than 2 cm. The inferior excision level, on the other hand, should be decided according to whether the invasion extends beyond the level of the 7th cervical vertebra. When the tumor invades down to the level of the thoracic vertebrae, total esophagectomy should be indicated because of the high incidence of skip lesions in the lower esophagus. For better prognosis, bilateral neck dissection is recommended, since hypopharyngeal cancer has high (more than 30%) incidence of contralateral neck metastasis except for well differentiated T2 lesions in the pyriform sinus. For reconstruction of the cervical esophagus, a one-stage technique using a pectoralis major myocutaneous flap has many advantages over other options, and technical details are reported here in this paper. In some patients, however, this technique is not advisable. In female patients with large breasts or thick subcutaneous fat, the flap cannot be utilized because of its bulkiness, and a newly developed technique that uses a skin-grafted pectoralis major muscle flap is indicated. For patients with a history of heavy radiotherapy, the use of the flap is also contra-indicated because of the risk of salivary fistula, and a staged operation using a deltopectoral skin flap is recommended.