Plexiform Fibrohistiocytic Tumour at a Rare Site: Frontal Region of Head with Underlying Frontal Bone Invasion.

Plexiform Fibrohistiocytic Tumour (PFHT) is an intermediate malignant tumour of soft tissue. It is a rarely metastasising dermal subcutaneous neoplasm. It affects children and young adults. The age range of presentation is from birth to age 77 years. The tumour is most commonly located on the upper extremities, whereas the involvement of the frontal region is rare. The differential diagnosis includes benign fibrous histiocytoma, fibromatosis, giant cell tumour and neurofibroma. Plexiform fibrohistiocytic tumour is a slow-growing mass and which is considered a low grade malignant tumour. Treatment is simple excision. It can exhibit aggressive behaviour and rate of local recurrence is 12-38%. A 45-year-old female was presented with a solid mass on the frontal region of the head which was diagnosed as a plexiform fibrohistiocytic tumour with underlying frontal bone invasion on histopathological examination of an excised mass in the Pathology Department. Plexiform Fibrohistiocytic Tumour (PFHT) is a mesenchymal neoplasm that shows a multinodular growth pattern and which is composed of fibroblasts, histiocyte-like cells and multinucleated osteoclast like giant cells. Clinically, it is usually a slow-growing mass with frequent local recurrence and rare regional lymphatic and systemic metastasis. [ABSTRACT FROM AUTHOR]