National Clinical-biological Prospective Cohort of Incident Cases of Aggressive Fibromatosis (ALTITUDES) (ALTITUDES)

National Clinical-biological Prospective Cohort of Incident Cases of Aggressive Fibromatosis (ALTITUDES)

Aggressive fibromatosis (AF) is a rare non-metastasizing connective tissue tumor (< 300 cases/year in France), associated with high risk of local relapse, functional impairment and pain. AF can occur at any age, but most commonly between 25 and 40 with a significant female predominance. AF is most frequently (about 85%) sporadic and then associated with a somatic mutation of the CTNNB1 gene. AF is associated with heredity condition, as complication of familial adenomatous polyposis (with germinal mutation of Adenomatous polyposis coli (APC) gene). Most of AF arises on lims or abdominal wall. Nevertheless, some particular locations are life-threatening (mesenteric or cervical locations). The natural course of AF is unpredictable. One third of tumors are spontaneously stable. One third of tumor spontaneously decreases. One third of tumor is progressive, with a non-linear tumor growth dynamic. As the consequence the decision making for starting curative intent treatment is difficult, since some treatment could be mutilating (large en bloc surgery) or associated with late and severe complications (radiotherapy) and since these treatments could fail to control this benign tumor. Therapeutic options are: wait-and-see policy, surgery (sometimes mutilating), radiotherapy or systemic treatment (non-steroidal anti-inflammatory drugs, hormonotherapy, imatinib, chemotherapy). Level of evidence associated these options is very low, based on retrospective studies and rare non-randomized phase II clinical trials. Regarding these uncertainties, physicians can hardly answer to patient questions. Prospective data provided by a large multi-center cohort is needed. The objective of the present study is to create a large cohort of incident cases of AF associated with tumor bank and collection of blood samples.

Tumor biobank realization (biopsy...) and biobank constitution. coloscopy associated with colonic chromoscopy. Blood sampling (facultative). Pain evaluation

Blood sample can be collected at diagnostic or after medically significant events (progressive disease, local or systemic treatment, pregnancy...)

Pain evaluation (EVA scale), anxiety (HADS questionnaire), quality of life questionnaire (EORTC-QLQ-C30)

Description of the management of AF. Study of prognosis factor for progressive disease and death. Study of tumor response to treatments (Best response and progression-free survival) according to RECIST 1.1.

To describe the psychological impact of the disease at diagnosis and a year after diagnosis. And to compare changes between the time of diagnosis and one year after the treatments used.

To describe the consequences of the disease on the quality of life at diagnosis and a year after diagnosis. And to compare changes between the time of diagnosis and one year after the treatments used.

To study the impact of pregnancy and hormonal exposure on the evolution of the disease according to recurrence/progression rates

To determine sensibility and specificity of cell free (circulating) nucleic acid extraction techniques

Inclusion Criteria: Incident Case of aggressive fibromatosis in France, diagnosed after 01/01/2016 Confirmed diagnosis by the French anatomopathological diagnosis network (including search for mutation of the β-Catenin Gene, CTNNB1) Affiliation to the National Health System Informed consent signed (both parents signature for non adult patients) Exclusion Criteria: Administrative or legal measure of liberty privation Patient not able to give consent or unwilling to provide consent

Penel N, Bonvalot S, Bimbai AM, Meurgey A, Le Loarer F, Salas S, Piperno-Neumann S, Chevreau C, Boudou-Rouquette P, Dubray-Longeras P, Kurtz JE, Guillemet C, Bompas E, Italiano A, Le Cesne A, Orbach D, Thery J, Le Deley MC, Blay JY, Mir O. Lack of Prognostic Value of CTNNB1 Mutation Profile in Desmoid-Type Fibromatosis. Clin Cancer Res. 2022 Sep 15;28(18):4105-4111. doi: 10.1158/1078-0432.CCR-21-4235.