INTRODUCTION
Nodular fasciitis (NF) or pseudosarcomatous fibromatosis was first
described in 1955 (1) and it is a rare benign condition in which
fibroblasts rapidly proliferate from the deep fascia to the adjacent
tissues, including muscle and subcutaneous tissue. It is a self-limited,
solitary lesion whose pathogenesis is still uncertain. NF seems to be
related to local traumas in only 10-15% of cases (2).
In most of the non-traumatic cases recent studies identified
rearrangements of the USP6 gene, often with MYH9 (3). In about half
patients local tenderness or pain is reported whereas paresthesia and
shooting pain is mostly present when NF involves the upper limbs. Given
the self-limiting nature of the lesion, the definition of “transient
neoplasia” has been proposed (3). NF shows no predilection for gender
or race, and affects the upper extremities (43%), the trunk (25%), and
head and neck district (10%) in young adults aged 20–40 years (2).
Differential diagnosis encloses, fibrosarcoma, fibroma, schwannoma,
fibrous histiocytoma, and desmoids. Histopathology and
immunohistochemistry play a pivotal role in diagnosis as FNAC might be
useful but not conclusive (4,5,6,7). In fact, NF can be correctly
diagnosed only if the cytologist is aware of its clinical and cytologic
features (8). After proper surgical excision recurrence is very rare
(2).