Pitfalls in the cytological diagnosis of nodular fasciitis: A report of two cases

Nodular fasciitis (NF) is a benign tumour that is often misdiagnosed due to its potential for rapid growth. There are limited case reports highlighting the cytomorphological features of this entity. We present two cases of nodular fasciitis that posed diagnostic challenges. The main features on cytological smears included bland, round to ovoid cells with indistinct cytoplasmic processes with focal cytological atypia in a background of focal myxoid change. Neither mitosis nor necrosis were observed. One of the cases was clinically suspected to be a pleomorphic adenoma, while the other was provisionally diagnosed as a pleomorphic sarcoma on fine needle aspiration cytology (FNAC). It is important to rule out NF on FNAC smears in the era of pre-operative chemo-radiotherapy. Misdiagnosis can result in unnecessary aggressive management.