Metastatic Adenoid Cystic Carcinoma at the Base of the Tongue and Duplicate Breast Cancer Diagnosed During Restaging.

Background/aim: Adenoid cystic carcinoma (AdCC) is a rare malignant tumor that primarily affects the salivary glands but can also occur in other organs. Low incidence and unpredictable clinical behavior make AdCC one of the most difficult head and neck tumors to treat.

Case report: We present the case of a 54-year-old woman with AdCC localized at the base of the tongue, following radical surgical and oncological therapy. Due to advances in palliative oncological treatment, there is a more than five-year survival period before the progression of metastatic disease. Considering the rare occurrence of this disease, a literature search was also conducted, and therapy options are discussed. Ensuring a sufficient extent of the surgical procedure is still a challenge, and most specialists agree that subsequent postoperative radiotherapy reduces the risk of local recurrence. The effective dose of radiotherapy to the area of the primary tumor and lymph nodes is not clearly defined.

Conclusion: The distinct biological behavior of AdCC results in varying sensitivity to chemotherapy or radiotherapy compared to treatments commonly used for head and neck squamous cell carcinomas. Treatment recommendations for these rarer tumors are based mainly on case reports and small clinical trials. The acquired therapeutic experience can contribute to prolonging the survival period of patients and improving their prognosis and quality of life.