Desmoid tumor is an aggressive fibromatosis that may occur in abdominal and extra-abdominal areas [1]. They constitute less than 0.03% of all neoplasms [2]. For extra-abdominal desmoids, local recurrence rates range from 24% to 77% in reported series [3–5]. Although the fibromatosis of chest wall represents 8-10% of all cases and surgery is the primary treatment modality, there remains a significant lack of agreement amongst surgeons on how to manage the disease that is suspected to have accompanied involvement of adjacent breast especially for an unmarried woman. We report a case where the tumour had a repeated recurrence over a 2-year period.
Case presentation
A 27 year-old unmarried female presented to our hospital with worsening pain of the right chest wall region and a recurrent obvious mass adjacent to the lower-inner quadrant of her right breast for 5 months. Two years prior to her current presentation, she presented to a local hospital with a palpable right chest wall mass close to the same quadrant of right breast and underwent a surgical resection. The histological examination showed a typical picture of an aggressive fibromatosis.
Physical examination showed a 15 cm and well-healed surgical scar along the inferior-inner aspect of her right inframammary fold. Plain and contrast-enhanced chest and epigastrium computed tomography (CT) showed a 10×5 cm mass on the right inferior chest wall that appeared to be in continuity with the right pectoralis major muscle and right rectus abdominis muscle (Figure 1A). Magnetic Resonance Imaging (MRI) of the breast and the chest confirmed a 9×4 cm mass in close proximity to the lower-inner quadrant of the right breast, with contact to the ribs (Figure 1B).
As diagnosis was established, surgery was scheduled. Under general anesthesia with selective intubation, the patient lay on the operating table with supine position. She underwent an en bloc resection of the tumor and the underlying musculature (inferior lateral portion of the right pectoralis major muscle and superior portion of the right rectus abdominis musculature, and anterior portion of the right latissimus dorsi muscle) and en bloc resection of the underlying chest wall structures (seventh rib and intercostal muscle). The defect on the right chest wall was then closed with a 10×10 cm Dacron patch. Although the mass was in close proximity to the lower-inner quadrant of the right breast, all surgical margins were negative with the intraoperative frozen section and the right mastectomy was avoided. Then the right breast was closed in the skin flap plasty. Patient was transferred to the intensive care unit and moved to general care after 24 hours and she was discharged to home after a week. She is currently under follow-up.
The surgically removed specimen was lobulated and 14×16×10 cm in size, containing a 10×12×8 cm tumor. Macroscopically, the bisected tumor showed a grossly circumscribed firm tumor with white, whorled patterns and without necrosis (Figure 1C, D). Microscopically, the lesion was composed of evenly spaced plump spindle cells arranged in intersecting fascicles and associated with mild to moderate amounts of collagen resembling keloid (Figure 2A, B). On immunohistochemical staining, the spindle cells were negative for S-100 protein and Epithelial Membrane Antigen (EMA). The spindle cells were positive for muscle-specific actin (MSA) (Figure 2C) and smooth muscle actin (SMA) (Figure 2D). The histology and immunohistochemical staining supported a diagnosis of fibromatosis (desmoid tumor).
