Extra-abdominal desmoid fibromatosis: A review of management, current guidance and unanswered questions. Eur J Surg Oncol. 2016;42:1071-1083. [PMID: 26965303 DOI: 10.1016/j.ejso.2016.02.012]

Desmoid-type fibromatosis of the breast: A report of 2 cases

Mammary fibromatosis is a rare and locally aggressive benign tumor of the breast; it originates from fibroblasts and myofibroblasts within the breast parenchyma and does not metastasize. The condition is locally aggressive and has a high rate of recurrence. The etiology of mammary fibromatosis is unknown. Breast imaging examinations are not specific for fibromatosis and often imitate breast cancer. The current study presents 2 cases of women with breast fibromatosis, the first of which exhibited a locally advanced aggressive form of the disease, where breast surgery and en bloc resection of the underlying regions of the thoracic wall were required. In the second case, breast imaging examinations suggested an invasive breast tumor, probably carcinoma, infiltrating the muscles of the chest wall. An ultrasound-guided core needle biopsy revealed a low-grade myofibroblastic proliferation consistent with breast fibromatosis. The patient underwent a right quadrantectomy, with a partial resection of the underlying musculature. The patients remain disease-free at the time of writing. As involvement of the breast in patients with desmoid-like fibromatosis as rare, the present study reports 2 cases with clinical features and histological findings in order to improve and add to the knowledge of this disease.

Biology and Treatment of Aggressive Fibromatosis or Desmoid Tumor

Aggressive fibromatosis, also known as desmoid-type fibromatosis (DTF) or desmoid tumor, is an uncommon locally invasive tumor. Because of its low incidence and variable behavior, DTF is often first seen by physicians who are not familiar with it, and recent advances in understanding this disease have led to changes in treatment approaches. The Wnt (β-catenin) pathway appears to play a key role in DTF pathogenesis, and recent studies of DTF biology suggest a possible model of DTF pathogenesis. Histologically, DTF shows a poorly circumscribed proliferation of myofibroblast-like cells with variable collagen deposition, similar to the proliferative phase of wound healing, and DTF has been associated with trauma and pregnancy. Desmoid-type fibromatosis may be a useful model of the tumor stroma in carcinomas as well as other fibrosing diseases such as progressive pulmonary fibrosis. The clinical course of DTF can vary greatly among patients, complicating the determination of the optimal treatment approach. Treatment options include surgery, nonsteroidal anti-inflammatory drugs with or without hormonal manipulation, chemotherapy, radiation therapy, and other forms of local therapy. Many treatments have been used, but these are not without toxicities. Because of the variable nature of the disease and the potential morbidity of treatment, some cases of DTF may do better without treatment; simple observation is often the best initial treatment. This review used a PubMed search from January 1, 1980, through October 31, 2016, using the terms fibromatosis and desmoid and discusses DTF disease characteristics, pathophysiology, and treatment options as well as examines several cases illustrating key points in the biology and treatment of this heterogeneous disease.

Carbon ion radiotherapy for desmoid tumor of the abdominal wall: a case report

Background

Desmoid tumors, which are associated with familial adenomatous polyposis (FAP), tend to occur frequently in the abdominal wall and mesentery. Currently, there are no recognized treatments other than surgery, and frequent surgeries result in gastrointestinal obstructions and functional gastrointestinal disorders.

Case presentation

After surgery that was performed on a 39-year-old patient with FAP, we performed a second tumor excision which was the procedure used for frequently occurring mesenteric desmoid tumors. It was determined that the enlarged tumor would be difficult to operate on through an abdominal incision. Subsequently, the carbon ion radiotherapy of 50 Gy was then performed on the patient. Three years later, the tumor still remains reduced in size. In addition, we have not observed any negative effect on the digestive tract.

Conclusions

This is the first instance that the carbon ion radiotherapy has been effective for the unresected desmoid tumor, and it is believed that this will become the one effective option for the treatment of desmoid tumors.