Abstract
BACKGROUND: Collision tumors are neoplasms in which two histologically different and topographically independent tumors are joined within the same mass. The aim of this paper is to present a rare case of collision carcinoma of the larynx (squamous cell and small-cell neuroendocrine carcinoma). CASE REPORT—DIAGNOSIS/TREATMENT: A 72-year-old patient was reported to our clinic because of hoarseness, dyspnea, and dysphagia. Neck CT showed a right-sided laryngeal tumor. The patient underwent total laryngectomy, partial pharyngectomy, and right-sided thyroidectomy with bilateral selective neck dissection. A clear collision of two morphologically and immunohistochemically different components of the tumor was seen on the sections sampled from the aryepiglottic fold. CONCLUSIONS: This case highlights the critical importance of obtaining multiple samples during tumor biopsy and emphasizes the role of detailed immunohistochemical staining. Considering the differences in histology, it is difficult to propose guidelines for treatment of these cancers.