Adult desmoid tumors: biology, management and ongoing trials.

In the past decade, we have learned that desmoid tumors are driven by alterations of the Wnt/APC/β-catenin pathway, sporadic desmoid tumors are associated with somatic mutations of CTNNB1, and germline mutations of APC and somatic mutations of CTNNB1 are probably mutually exclusive. One-third of desmoid tumors are misdiagnosed; a second pathological opinion is therefore of major importance for desmoid tumor. Surgery is no longer regarded as the cornerstone of desmoid tumors; several retrospective studies have demonstrated the safety of a ‘wait and see’ policy in sporadic abdominal wall desmoid tumor. Desmoid tumors is no longer regarded as an absolute contraindication for pregnancy. At least two new investigational drugs targeting the Wnt/APC/β-catenin pathway are currently being developed.

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 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.

Desmoid tumors are benign neoplasms, but are often unresectable because of their aggressive and local infiltration, compression of surrounding structures and massive involvement of adjacent vital structures. This is a case of a 43 year old woman with medical history of Berger’s disease, immunosuppressive therapy, a kidney transplant and sporadic mesenteric desmoid tumors appearing after solid organ transplantation. Eighteen months after the removal of the tumors, she was diagnosed with essential thrombocytosis. No evidences of recurrence after operation.

This study investigates the feasibility of non-invasively determining thermal diffusivity (alpha) and the Pennes perfusion parameter (w) from pre-clinical and clinical magnetic resonance-guided focussed ultrasound (MRgFUS) temperature data. Pre-clinical MRgFUS experiments were performed in rabbit muscle (N=3, 28 sonications) using three-dimensional MR thermometry. Eight sonications were made in a clinical QA phantom with two-dimensional thermometry. Retrospective property determination was performed on clinical uterine fibroid (N=8, 9 sonications) and desmoid tumour (N=4, 7 sonications) data. The property determination method fits an analytical solution to MRgFUS temperatures in the coronal MR plane, including all temperatures acquired during heating and one cooling image. When possible, additional cooling data were acquired for property determination. Rabbit alpha and w from Heating Data (alpha=0.164 mm2s-1, w=7.9 kg m-3 s-1) and Heating and Cooling Data (alpha=0.146mm2s-1, w=3.3 kg m-3 s-1) were within the range of gold-standard invasive measurements, with >50% reduction in variability by including cooling data. QA phantom property determination with cooling data yielded properties within 3% of expected values (alpha=0.144 mm2s-1, w=0.0 kg m-3 s-1), a difference that was not statistically significant (p = 0.053). Uterine fibroid (Heating Data: alpha=0.212 mm2s-1, w=11.0 kg m-3 s-1) and desmoid tumour (Heating & Cooling Data: alpha=0.245 mm2s-1, w=4.7 kg m-3 s-1) properties are feasible but lack independent verification.Thermal diffusivity and the Pennes perfusion parameter can be obtained from in vivo data and with clinical MRgFUS protocols. Property values are consistently improved by including cooling data. The utility of this property determination method will increase as clinical protocols implement improved temperature imaging.

Desmoid tumors are benign tumors, yet can lead to significant morbidity due to aggressive local expansions. Treatment starts with a wait-and-see policy, however, more aggressive treatments like broad margin resection surgery might be necessary in case of tumor progression. We report the case of a 26-year-old female with a symptomatic desmoid tumor in the left rectus muscle. The initial wait-and-see policy led to an increase in tumor size and progression of symptoms. Computed tomography (CT) angiography revealed a dominant arterial blood supply via a branch of the inferior epigastric artery. We then performed a super selective embolization of the dominant arterial blood supply, to avoid the need for broad margin resection. At three months follow-up, the patient was asymptomatic and magnetic resonance imaging (MRI) showed no residual tumor. At nine months follow-up, MRI scan reconfirmed the successful outcome. Embolization of a primary supplying vessel of a desmoid tumor is a viable treatment option. However, scientific evidence remains limited and further research is mandatory for inclusion in evidence based treatment algorithms.

We report the consecutive cases of two patients who had multiple recurrences of locally advanced desmoid tumors and for whom treatment with combined medical and surgical approaches had failed. Both patients then had a major objective response to treatment with a combination of celecoxib and sorafenib. The outcomes for these two patients provide potential equipoise for controlled studies of the celecoxib_sorafenib combination in patients with refractory desmoid disease associated with familial adenomatous polyposis.