SYSTEMATIC ANALYSIS OF CERVICAL LYMPH-NOD E METASTASES IN LARYNGEAL AND HYPOPHARYNGEAL CARCINOMAS - A CLINICAL AND COMPUTED-TOMOGRAPHY STUDY WITH SPECIAL REGARD TO THE LOCATION AND EXTENSION OF THE PRIMARY TUMOR

Purpose: To assess the incidence and patterns of cervical lymph node m etastases in laryngeal and hypopharyngeal carcinomas according to the location, extension, and relation of the primary tumor to the paraphar yngeal compartments and tissues arising from different embryological s tructures as branchial arches and somites, Patients and Methods: The f indings of clinical and CT examinations of 230 patients with histologi cal evidence of laryngeal and hypopharyngeal carcinoma (44 T1-, 33 T2- , 41 T3-, 112 T4-carcinomas with lymph node involvement in 116 cases) were evaluated retrospectively. Local tumor spread and relation of the primary to the parapharyngeal compartments and to tissues arising fro m different embryological structures such as branchial arches and somi tes were analysed and related to cervical lymph node involvement. Resu lts: The pattern of cervical lymph node involvement depends upon locat ion and extension of the primary tumor in the adjacent tissues of the larynx and hypopharynx. The density of the lymphatic vessels in these areas determines the likelihood of lymph node involvement. The frequen cy of NO cases in carcinomas strictly located in the vocal cord (n=31) was 100%; in the glottic-supraglottic, supraglottic, and transglottic cancer (n=106) 85%; in larynx-hypopharynx carcinomas (n=54) 26%; in h ypopharynx carcinomas (n=12) 17%; and in larynx-hypo-oropharynx carcin omas (n=46) 9%. Tumors in tissues arising from branchial arches 4, 5, and 6 are glottic-supraglottic, transglottic laryngeal, and laryngeal- hypopharyngeal carcinomas. Metastases of these tumors were frequently found in the jugular lymph node chains, particularly if the developed tissue of the ''primitive glottis'' was invaded by the primary. Upper jugular nodes ipsilateral to a supraglottic or hypopharyngeal primary were usually involved. The frequency of metastases in the jugular lymp h node chains decreased in craniocaudal direction. if the tumor invade d the posterior wall of the hypopharynx or tissues arising from occipi tal and cervical somites (retropharyngeal compartment and recessus sub musculares), metastases in retropharyngeal, spinal-accessorial, and tr ansversa-colli lymph nodes were found. Juxtavisceral lymph node metast ases were found if the primary invaded the prelaryngeal compartment. C onclusions: Knowledge of regular patterns of spread of laryngeal and h ypopharyngeal carcinomas is important for treatment procedures especia lly for 3-dimensional radiotherapy and neck dissection procedures.