Diagnosis and Management of Desmoid Fibromatosis of the Breast

Abstract

Desmoid fibromatosis of the breast (also known as desmoid tumor of the breast) is a rare entity infrequently encountered by oncologists and surgeons caring for patients with breast disease. The current body of literature is highly reliant on case series and extrapolations from other sites of desmoid tumor-related disease. Much remains unclear regarding the pathological origins, natural history, and response to treatment of this condition. Traditional treatment strategies have centered on surgical resection, which may result in significantly disfiguring cosmetic and functional outcomes, frequent need for re-operation, and associated morbidity. There are limited data to support the superiority of upfront surgical resection when compared to medical therapy or watchful waiting strategies. Current treatment guidelines for desmoid tumors do not focus on the breast as a site of disease and are purposefully ambiguous due to the paucity of evidence available. We aim to review the literature concerning desmoid fibromatosis of the breast and propose an algorithm for current evidence-based management of this rare disease in the context of our experience with this pathology at a high-volume quaternary referral center.

Keywords: Breast fibromatosis; Breast surgery; Desmoid fibromatosis; Desmoid tumor; Soft tissue tumors.

Figure 1

Fibromatosis infiltrating around normal breast epithelium (black arrow).

Figure 2

The spindle cells of fibromatosis show aberrant β-catenin nuclear immunoreactivity (black arrow).

Figure 3

Low power show moderate cellularity with alternating hypocellular (black arrow) and hypercellular area (red arrow) and lacking circumscription.

Figure 4

(a) Long sweeping fascicles (black arrows) and intersecting fascicles (red arrows) are characteristic of desmoid tumor of breast. (b) Bland spindle cell proliferation (black arrows), nuclei are elongated with rounded ends and lack nuclear pleomorphism and demonstrate no mitoses

Figure 5

Proposed management algorithm for breast fibromatosis.