title: Primary Merkel cell carcinoma of the oral mucosa in a young adult male: report of a rare case.
abstract: Merkel cell carcinoma (MCC) is a highly aggressive neoplasm of skin with neuroendocrine differentiation. Primary MCC of the oral mucosa is exceedingly rare and even more unresponsive to therapy. A 15-year-old male presents with gradually increasing painless swelling in right side of the floor of mouth for 6 weeks. Computed tomography of head and neck region showed globular mass (4.6 cm × 1.7 cm) involving right side of the floor of mouth. Fine-needle aspiration from the upper deep cervical node suggested small round cell tumor. A trucut biopsy showed mass composed of trabeculae and nests of tumor cells with high N:C ratio, granular speckled chromatin, scanty to moderate amount of clear vacuolated cytoplasm. Cells were immunoreactive for cytokeratin-20, CD56, c-kit, CD99 and negative for p63, thyroid-transcription factor-1, CDX2, synaptophysin, neuron-specific enolase. Patient was started on chemotherapy with cyclophosphamide, doxorubicin and vincristine. The mass regressed in size and patient underwent wide local excision with pull-through approach. Patient is currently under combined chemoradiation regime and doing well.
authors.forename: Shravasti
authors.initials: S
authors.lastname: Roy
authors.forename: Indranil
authors.initials: I
authors.lastname: Das
authors.affiliation: Medical College, Kolkata, West Bengal, India.
authors.forename: Ayandip
authors.initials: A
authors.lastname: Nandi
authors.forename: Rakesh
authors.initials: R
authors.lastname: Roy
mesh_terms: D000293:Adolescent; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D044963:Biopsy, Fine-Needle; D015266:Carcinoma, Merkel Cell / Q000175:diagnosis* / Q000473:pathology*; D006257:Head / Q000000981:diagnostic imaging; D006651:Histocytochemistry; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008853:Microscopy; D009061:Mouth Mucosa / Q000473:pathology*; D009062:Mouth Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D009333:Neck / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed
chemical_list: D014408:Biomarkers, Tumor