Fine needle aspiration cytology diagnosis of the eccrine variant of chondroid syringoma- case report of a rare entity with review of literature

Chondroid syringomas (CS) are rare mixed tumours of sweat-gland origin which were first described by Billroth in 1859, that have both benign and malignant forms. They are also known as mixed tumours of the skin and are composed of both epithelial and mesenchymal components. A 40-year-old female presented to the surgical outpatient department with a gradually increasing swelling over the side of the nose, of 1 year duration. FNAC was done and the aspirate was thick and mucoid. Microscopic examination revealed clusters of epithelial and myoepithelial cells, embedded in a metachromatic, chondromyxoid ground substance. Based on these features, a diagnosis of chondroid syringoma was made and histopathological examination was advised. On histopathological examination, it was found that there were numerous nests of polygonal cells and interconnecting tubuloalveolar structures whicha were lined by a single layer of cuboidal epithelial cells. The stroma consisted of cells in a bluish chondroid matrix. Based on these findings, a diagnosis of the eccrine variant of CS was given. The patient was well after excision and no recurrence was reported. CS is a rare primary skin tumour; the incidence is < 0.098% and affects middle aged and older men. The most common sites are the head and neck region, the hand, foot, the axillary region, the abdomen, penis, vulva and the scrotum. Fine needle aspiration cytology has been used for diagnostic purposes and may prove to be useful to determine the pathology before excision of the tumour. However, examination of excised tissue is most reliable in establishing a definitive diagnosis.