Metastasis of tongue cancer located unilaterally, not crossing the midline, to the lymph nodes of the neck

Introduction: In recent years, there has been a steady increase in the incidence of tongue cancer. Rapid asymptomatic growth, early metastases, and crossing lymphatic drainage of the tongue reduce the chances of successful therapy. The presence of metastases in cervical lymph nodes is also an important prognostic factor. Aim: The aim of the study is a retrospective analysis of the incidence of unilateral and bilateral metastases within the cervical lymphatic system in patients with unilateral tongue cancer that does not cross the midline. Materials and methods: A retrospective study of a group of patients hospitalized and treated for malignant tongue cancers at the Clinical Ward of Cranio-Maxillo-Facial Surgery of the Department of Otolaryngology and Laryngological Oncology of the Military Institute of Medicine-National Research Institute in Warsaw in 2012-2023. As many as 106 patients treated for unilateral tongue cancer that has not crossed the midline were selected, who also underwent unilateral or bilateral cervical lymphadenectomy, apart from primary tumor resection and reconstruction. The analysis was based on the medical records of the patients, results of imaging and histopathological examinations, and surgical procedure protocols. Results: In a group of 106 patients with unilateral tongue cancer, in whom the cancer did not cross the midline, 47 patients underwent unilateral lymphadenectomy, of which 16 had lymph node metastases. Bilateral lymph node removal was performed in 59 patients. In 26 cases metastases were detected only in ipsilateral lymph nodes, and in 13 cases metastases were found in contralateral lymph nodes. Among 106 patients, occult metastases were detected in 21 patients. Conclusions: Due to the crossing of the lymphatic drainage of the tongue, which allows for the possibility of contralateral metastases, and the impact of the operation on oncological efficacy, it is reasonable to perform bilateral cervical lymphadenectomy.