Primary adenocarcinoma of the base of tongue: a case report and review of the literature

BACKGROUND: Primary adenocarcinoma of the base of the tongue is an exceptionally rare malignancy, accounting for only a small proportion of oropharyngeal tumors. Diagnosis is challenging due to nonspecific symptoms and overlap with more common squamous cell carcinomas and salivary-type neoplasms. CASE PRESENTATION: We report the case of a 59-year-old Moroccan woman presenting with progressive dysphagia and referred otalgia. Nasofibroscopy revealed a right-sided base of the tongue mass extending to the vallecula. Magnetic resonance imaging confirmed a 28 × 19 mm lesion with ipsilateral cervical lymphadenopathy. Biopsy demonstrated an undifferentiated invasive adenocarcinoma. Immunohistochemistry was positive for CK7 and CK20 and negative for p16. The patient underwent transmandibular resection with bilateral neck dissection, followed by adjuvant radiotherapy. At 6-month follow-up, she remained disease-free with good functional outcomes. METHODS: A narrative systematic review was conducted in PubMed, Scopus, and Google Scholar using predefined keywords. Studies reporting primary base of the tongue adenocarcinoma were included. RESULTS: A total of 12 publications describing comparable cases were identified. Most patients presented with dysphagia and cervical lymphadenopathy. Surgery followed by radiotherapy was the most commonly reported management strategy. Prognosis appeared favorable in low-grade salivary-type tumors and more variable in high-grade or nonsalivary primaries. CONCLUSION: Primary base of the tongue adenocarcinoma is rare and requires a high index of suspicion and appropriate immunohistochemical evaluation. Multimodal management offers good oncologic control. Long-term follow-up is necessary due to uncertain metastatic potential.