Merkel-type oral small cell neuroendocrine carcinoma as seco
A 56-year-old male patient had a history of squamous cell carcinoma of the right ventral tongue and floor of the mouth. The neoadjuvant chemotherapy, wide excision, and post-surgical radiation therapy were performed seven years ago. After treatment, he was under a regular follow-up every three months. In the last follow-up, the patient complained of dysphagia and slurred speech for one month. Two exophytic masses were present over the posterior dorsal tongue and right lateral border of the tongue respectively. The masses revealed ulcerated surfaces, irregular borders, and firm inconsistencies. The clinical examination revealed no cervical lymphadenopathy, and the tentative diagnosis was a second primary squamous cell carcinoma. Then the incisional biopsy of the dorsal tongue lesion was performed. Microscopically, it showed sections of nodular lesion covered by ulcerative surface with aggregation of small, basophilic cells in the stroma. The tumor cells showed a high nuclear to cytoplasmic ratio and hyperchromatic, pleomorphic, round to oval nuclei. Abundant mitotic figures and confluent foci of necrosis were also identified. Immunohistochemically, the tumor cells showed punctate para nuclear staining with cytokeratin (CK) (AE1/AE3) and CK20. The tumor cells were also positive for the neuroendocrine markers, including CD56, synaptophysin, and chromogranin. The histopathological diagnosis was a Merkel-type oral small cell neuroendocrine carcinoma. Subsequently, the patient underwent several general surveys including oral and chest computed tomography, abdominal magnetic resonance imaging, esophagogastroduodenoscopy, and general bone scan. The results revealed suspicious metastatic lymphadenopathy in the left upper mediastinum and a metastatic lesion in the liver. He was under chemotherapy with cisplatin and etoposide, and the size of the oral lesion decreased continuously during the regular follow-up; however, he expired from septic shock and respiratory failure six months after diagnosis.