A large and aggressive fibromatosis in the axilla: a rare case report and review of the literature

Fibromatosis with aggressive demeanor: Benign impersonator of malignancy

Fibromatosis or desmoid fibromatosis is a rare benign neoplasm and develops commonly in the abdominal wall, abdominal cavity, or extra-abdominal sites. The mainstay of treatment is surgery. Chemotherapy and radiotherapy are preferred in cases of inoperable/relapse or a multifocal disease. Hereby, we report a case of fibromatosis arising in the left popliteal fossa, proven by histopathology and immunohistochemistry. Local excision of the mass was performed. The patient was asymptomatic for 6 months, after which she complained of difficulty in walking. Clinical evaluation elicited recurrence in the surgical bed. In spite of the surgical excision with tumor-free margins, recurrence was seen within a span of 6 months. ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET/CT) was done to rule out multifocal disease and to define the extent of relapse. Although magnetic resonance imaging provides an excellent soft-tissue resolution to delineate the disease, ¹⁸F-FDG PET/CT is an important and supplementary tool which aids in the management of fibromatosis.

Abnormal Presentation of Aggressive Fibromatosis After Radiotherapy for Keloids: Case Report and Brief Literature Review

RATIONALE

Keloids, dermal fibroproliferative lesions, often occur secondary to skin injury and extend beyond the margins of the original lesion. Aggressive fibromatosis (AF) is a rare condition arising from fibroblasts and is characterized clinically as a nonmetastasizing but locally invasive tumor. In this work, we present the case of a patient who developed AF in the chest 3 years after surgery and postoperative radiotherapy for keloids.

PATIENT CONCERNS

A 15-year-old female patient who underwent surgery and postoperative radiotherapy for keloids presented with AF in the chest 3 years after intervention.

DIAGNOSES AND OUTCOMES

Physical examination revealed a fan-shaped scar on the manubrium sterni with a radius of 7 cm, as well as a 9 (L) × 2-cm (W) longitudinal reddish and irregularly surfaced scar arising from previous incisions. By comparing this case with similar cases reported previously, we infer that a history of exposure to radiation is the main factor that contributes to the development of AF in patients suffering from keloid scars. We also discussed the clinical characteristics of AF and treatment options and suggest factors that should be considered when using radiotherapy in patients with keloids.

LESSONS

To our knowledge, this is the first reported case of AF developing in a patient after radiotherapy for keloids. Radiotherapy may be a causal factor of AF.

Intra-abdominal desmoid tumor mimicking local recurrence of renal cell carcinoma after laparoscopic partial nephrectomy

A 64-year-old man had an intra-abdominal mass that was detected in a follow-up examination after laparoscopic partial nephrectomy for renal cell carcinoma (RCC). CT showed an enhanced mass of 2.5-cm diameter near the right kidney, where partial nephrectomy had been performed. Local recurrence of RCC with duodenum invasion was suspected, and excision was performed. The final pathological diagnosis of desmoid tumor differed from the preoperative diagnosis. Therefore, we report this case as a rare example of intra-abdominal desmoid tumor mimicking local recurrence of RCC. To our knowledge, this is the first report of intra-abdominal desmoid tumor after laparoscopic partial nephrectomy.