Primary intra-abdominal desmoid fibromatosis associated with familial adenomatous polyposis: A case report.

Desmoid fibromatosis (DF) is a clonal proliferative disorder of myofibroblasts, which arises, with a low incidence, in soft tissue, including within the abdomen. The incidence of DF is associated with familial adenomatous polyposis (FAP), and is more common following FAP surgery. It is rare for a patient to make his/her first visit to hospital due to DF symptoms associated with FAP. In the present report, a case of mesenteric DF associated with FAP is described. This case also had incomplete intestinal obstruction due to DF. By summarizing previous studies examining DF and FAP treatment, combined with the disease characteristics of this patient, the clinical treatment strategy for DF associated with FAP was explored.

PURPOSE OF REVIEW: Desmoid tumor is a rare disease of intermediate malignancy characterized by a locally aggressive monoclonal, fibroblastic proliferation and accompanied by a variable and often unpredictable clinical course. The purpose of this review is to give an overview on the emerging new systemic treatment options for this intriguing disease for which no established or approved drugs are available yet. RECENT FINDINGS: Over decades, surgical resection has been the established initial treatment approach; however, more recently, a paradigm shift has been introduced towards a more conservative treatment strategy. Almost 10 years ago, The Desmoid Tumor Working Group has initiated a consensus process initially in Europe and then globally with the intention to harmonize the therapeutic strategy amongst clinicians and set up management recommendations for desmoid tumor patients. SUMMARY: This review will summarize and focus on the latest emerging impressive data on the use of gamma secretase inhibitors in this disease paving a possible future perspective in the treatment armamentarium for desmoid tumor patients.

BACKGROUND: Fibroblastic soft-tissue tumors share enzymatic anomalies that result in excessive intracellular conversion of 5-aminolevulinic acid (5-ALA) to protoporphyrin IX, a photosensitizer which induces cellular apoptosis upon exposure to visible red light at a wavelength of 635 nm. We hypothesized that red light illumination of the surgical bed remaining after resection of fibroblastic tumors will result in destruction of microscopic tumor residua and may decrease the likelihood of local tumor recurrence. METHODS: Twenty-four patients with desmoid tumors, solitary fibrous tumors (SFT), and dermatofibrosarcoma protuberans (DFSP) received oral 5-ALA prior to resection of their tumors. Following tumor resection, the exposed surgical bed was illuminated with red light at a wave length of 635 nm at a dose of 150 J/cm(2) for 33 min. RESULTS: Treatment with 5-ALA was associated with minor side effects that included nausea and transient elevation of transaminases. Local tumor recurrence was detected in 1 of the 10 patients with desmoid tumors who had not undergone any previous surgery, none in the 6 patients who had SFT and 1 of the 5 patients who had DFSP. CONCLUSIONS: 5-ALA photodynamic therapy of fibroblastic soft-tissue tumors may result in decreased likelihood of local tumor recurrence. It is associated with minimal side effects and should be considered as adjuvant to tumor resection in these cases.

OBJECTIVE: In this study, we aimed to describe the clinical features, management, and outcomes of desmoid tumors (DTs) in familial adenomatous polyposis (FAP) patients at a high-volume sarcoma center. METHODS: Consecutive patients with FAP and DTs were identified from our institutional databases (1985-2021). Patient demographics, treatment, and outcomes were described. Categorical data were compared using Fisher’s exact test, and Kaplan-Meier curves were used to estimate progression-free survival (PFS). RESULTS: Forty-five patients with 67 DTs were identified: 39 mesenteric or retroperitoneal (58.2%), 17 abdominal wall (25.4%), 4 extremity (6%), 4 breast (6%) and 3 back (4.4%). Severe DT symptoms were present in 12 patients (26.7%). Initial treatments per tumor were observation in 30 (44.8%) DTs, chemotherapy in 15 (22.4%) DTs, surgery in 10 (14.9%) DTs, and other systemic therapies in 10 (14.9%) DTs. The majority of DTs remained stable with observation or a single intervention (77.8%). Median PFS was 23.4 years (95% confidence interval 7.6-39.2). In the 12 severely symptomatic patients, four patients required more than two interventions for DT control. At a median follow-up of 6.0 years (range 0.7-35.8 years), 33 (73.3%) patients were alive with disease, 7 (15.6%) were alive without disease, and 5 (11.1%) died of other causes. No patients died of DT-related complications. CONCLUSIONS: The majority of DTs in FAP patients remained stable with observation or a single intervention. There were no DT-related deaths; however, 12 of 45 patients (26.7%) experienced significant tumor morbidity and required more interventions for disease control. Further studies on quality of life are required.

Mesenteric fibromatosis is a rare tumor that grows slowly and asymptomatically and is more frequent among men. The risk factors described in the literature may not be present in all cases. The clinical presentation is variable and depends on the localization of the tumor and the involvement of surrounding structures. Imaging studies such as abdominal computed tomography and magnetic resonance imaging are the preferred methods for the diagnosis of this tumor. However, a definitive diagnosis is made based on histopathology and immunohistochemistry results. Surgical resection remains the preferred option for the treatment of mesenteric fibromatosis. This report presents a clinical case of mesenteric fibromatosis in a male patient who presented with partial abdominal obstruction and the absence of risk factors for mesenteric fibromatosis.