Desmoplastic fibroma of bone in a toe: radiographic and MRI findings.

Desmoplastic fibroma is a rare benign primary bone tumor that is histologically similar to the soft tissue desmoid tumor. It most often involves the mandible, large long bone or iliac bone. Desmoplastic fibroma in a toe has been extremely rarely reported.

Desmoplastic fibroma (DF) of the bone is a rare locally aggressive tumor usually occurring in adolescents and young adults. These tumors most commonly occur in the mandibles and metaphyses of long bones but are extremely rare in small bones, often resulting in diagnostic problems. The occurrence of these tumors in the foot is especially limited. We report the clinical, radiographic, and histologic features of DF arising in the distal phalanx of the great toe and a review of the published data.

Aggressive fibromatosis, previously referred to as desmoid tumor, is a rare tumor. It is classified as benign, however, has a high potential for local invasion and recurrence. It is most commonly found in the abdomen, with an origin in the head and neck accounting for less than a quarter of the total cases.

An asymptomatic 66-year-old woman showed a large perineal mass extending close to pelvic organs on MRI. CT-guided needle biopsies revealed a desmoid tumour (DT). The patient refused radical surgery. Four years later, the tumour had marginally increased in size and was still asymptomatic.

The pattern of myometrial invasion in endometrioid endometrial carcinomas varies considerably; ie, from widely scattered glands and cell nests, often associated with a fibromyxoid stromal reaction (desmoplasia) and/or a lymphocytic infiltrate, to invasive glands with little or no stromal response. Recently, two distinct stromal signatures derived from a macrophage response (colony-stimulating factor 1, CSF1) and a fibroblastic response (desmoid-type fibromatosis, DTF) were identified in breast carcinomas and correlated with clinicopathologic features including outcome. In this study, we explored whether these stromal signatures also apply to endometrioid carcinomas and how their expression patterns correlated with morphologic changes.

We report the outcome of two patients affected by progressive DT/AF treated with the angiogenesis inhibitor pazopanib in two different institutions. Both patients achieved dramatic improvement in their symptoms and radiological signs of response. The clinical benefit lasted for more than 1 year and it is still ongoing.