[Contralateral metastasis in patients with cancer of the larynx and the hypopharynx. Analysis and critical review of our caseload].

Cancers of the hypopharynx (pyriform fossa, post-cricoid area and posterior wall) and larynx show a high tendency to invade the cervical lymph nodes. Such nodal extension is a well known prognostic factor. In general, those lesions that are in well-lateralized primary sites (pyriform sinus, aryepiglottic fold...) tend to metastasize to the ipsilateral side of the neck. This concept, however, is fraught with exceptions; any lesion, especially with ipsilateral metastases, creates a risk for contralateral node involvement. The present study is based on a retrospective review of 450 clinical records of patients affected by well-lateralized laryngeal (301 pt.) and hypopharyngeal (149 pt.) carcinomas. The incidence of contralateral metastases was analyzed for this group; 25 out of 310 patients with laryngeal cancer (8.3%) and 20 out of 149 with hypopharyngeal cancer (13.4%) showed metastatic involvement of the contralateral neck. In patients with laterally oriented primary lesions, the initial appearance of cervical adenopathy is rarely contralateral since contralaterality is almost a manifestation of bilaterality of metastases. A contralateral disease is rarely possible even if the homolateral neck has been surgically treated. This is because of shunted lymph flow through the submental and submandibular lymphatics. Isolated contralateral disease was only found in 4 patients (1.3%): such data do not suggest any systematic, elective treatment of the contralateral neck NO in patients with unilateral laryngeal and hypopharyngeal cancers.