Synchronous malignant neoplasm in the oral cavity - case report

Approximately 555,000 new cases of head and neck cancer (HNC) are diagnosed annually worldwide. Moreover, second primary malignancy (SPM) occurs more commonly in the head and neck than in any other body region. A 67-year-old female patient was admitted to our Department for removal of an upper lip tumor. The patient underwent excision of the lip tumor under general anesthesia. Postoperative histopathology revealed a polymorphic, low-grade adenocarcinoma. Three weeks later, the patient was re-admitted to extend the margin of excision and perform lymphadenectomy. On physical examination, a second primary synchronous lesion was found on the left side of the hard palate. Lymphoscintigraphy was performed to determine the lymph node field and the sentinel lymph node. On ultrasonography, the lymph nodes were not enlarged. Extended excision of the upper lip was performed, and a 5-mm, hard palate tumor was removed with a margin of unchanged tissue. The patient was scheduled for adjuvant treatment. The criteria for a synchronous malignancy are as follows: both tumors must be malignant on histopathology, there must be a distance of at least 2 cm of unchanged mucosa between the index tumor and the primary tumor, the possibility that the second tumor is the metastasis of the index tumor needs to be excluded. In our patient, all these criteria were met. A thorough workup should include medical history, physical evaluation, and imaging, and it should be carried out on every step of treatment and during long-term follow-up in patients after cancer treatment. This is crucial, because not only is there a possibility of recurrence or metastases, but also a considerable percentage of patients may have a second primary lesion.