Table 19.

Statements pertaining to desmoid tumours—extended version

Statements
Diagnosis and screening
DTs.1 Value of classifications—can they help guide treatment? The different classifications can help in the choice of treatment; however, they must be strongly related to the clinical presentation and evaluation by the physician.
DTs.2 Should know FAP patients with high risk factors undergo abdominal desmoid screening (before surgery)? Preoperative screening for desmoid tumour appears more relevant in patients who already had abdominal surgery as it might find a DT that can have impact on the surgical options choice.
DTs.3 Should FAP patients undergo a post-colectomy screening programme for abdominal desmoid tumours? There is no evidence in the literature that a screening programme for desmoid tumour detection after abdominal surgery should be proposed. Moreover, with the actual possible treatment and the unpredictable evolution of DT, such a screening programme might not be needed.
DTs.4 Is a confirmatory biopsy required for the diagnosis of an intra-abdominal or abdominal wall desmoid in an FAP patient? Confirmatory biopsies may be considered if there is a diagnostic dilemma or required to initiate medical therapy.
DTs.5 Should the diagnosis of DT in a patient without known FAP mandate exclusion of FAP? In a patient with desmoid tumour/s without known FAP, screening of FAP (at least with colonoscopy and APC mutation testing if possible) should be performed. This is especially important among patients <60 years, or with intra-abdominal desmoids or in the abdominal wall.
Treatment
DTs.6 Which desmoid requires treatment? Rapidly enlarging and life-threatening desmoid tumour requires first-line aggressive treatment. Others should be surveyed in a watch-and-wait protocol.
DTs.7 Is surgery the ideal treatment for desmoid tumours? Surgery could not be considered the ideal treatment for desmoid tumours, except in the case of DT complications, rapidly growing or life-threatening.
DTs.8 Should patients at high risk for desmoids receive chemoprevention after colorectal surgery? There is currently no evidence to support the use of chemoprevention for high-risk patients undergoing surgery or in post-surgical care.
Management for DTs identified during abdominal surgery
DTs.9 What is the ideal strategy in patients with intraoperative findings of an unexpected desmoid tumour or precursor lesion(s)? A: We recommend continuing with the intervention (proceeding with the surgical procedure) if technically feasible. B: Resection of mesenteric desmoid(s) should be avoided if it will result in sacrificing any small bowel.
DTs.10 Can desmoid tumours modify the strategy of prophylactic (procto)colectomy? Desmoid disease can potentially render restorative procedures technically challenging or impossible. In cases where it is feasible, restorative procedures should be cautiously considered and selectively recommended for patients with concomitant intra-abdominal desmoid tumours following prophylactic (procto)colectomy, taking into account the significant risk of desmoid recurrence and adhesion formation. In such circumstances, proctocolectomy with terminal ileostomy may represent the safest option. It is important to have a thorough discussion with the patient about the potential risks of compromised function and the possibility of requiring additional surgeries, ensuring that the choice is individualized to their specific situation.
DTs.11 What is the incidence of desmoid tumours at the site of an ileostomy? The risk of desmoid tumours has not been evaluated on a systemic scale. When feasible, single-stage proctocolectomy is preferred for FAP patients in order to avoid desmoid tumours.

DT, desmoid tumour; FAP, familial adenomatous polyposis.