Clinicocytopathological spectrum, including uncommon forms, of nine cases of chordomas with immunohistochemical results, including brachyury immunostaining: A single institutional experience.

Abstract

To present clinical and cytopathological features of nine cases of chordomas, diagnosed over 9years and confirmed by brachyury (T) immunostaining. Conventional cytological smears, stained with Papanicolaou and May-Grünwald Giemsa, along with corresponding histopathological (n=8) and immunostained sections (n=8) were reviewed. Immunohistochemical staining was performed on tissue sections by polymer detection technique. Nine tumours occurred in seven males and two females, with age ranging from 36 to 72years (average=58.7), in the sacrum (seven) and spine (two). On fine needle aspiration cytology, five cases were either diagnosed with or diagnosed with a suggestion of a chordoma, while three cases were diagnosed with chordoma as a differential diagnosis. On review, smears were moderately cellular, comprising myxoid stroma (9/9), epithelioid cells (9/9), physaliphorous cells (8/9), including binucleation (7/9), prominent nucleolisation (2/9), pleomorphic cells (2/9) and intranuclear inclusions (3/9). Immunohistochemically, tumour cells expressed cytokeratin (4/4), pan cytokeratin (4/4), epithelial membrane antigen (8/8), S100 protein (6/8) and brachyury (8/8). Five patients underwent surgical excision, including two who underwent adjuvant radiotherapy (RT) and four patients who underwent RT. During follow-up (n=8), a single patient developed recurrence and another presented with metastatic lesions. Finally, five patients were alive with disease (7-53months); a single patient was free of disease (4months), and two patients died of disease; the latter cases displayed pleomorphic cells and intranuclear inclusions. Chordomas can be primarily diagnosed by fine needle aspiration cytology in a typical clinicoradiological setting with a combination of key cytomorphological features. Pleomorphic cells and intranuclear inclusions are associated with a relatively aggressive subtype. An exact diagnosis has treatment implications and requires confirmation by brachyury immunostaining.