Malignant Transformation in Perianal Fistulas of Crohn’s Disease: a Systematic Review of Literature

Abstract

A high suspicion for malignancy in chronic perineal fistulas associated with Crohn's disease should be maintained in spite of negative biopsies. Especially in women, the shorter duration of Crohn's fistulas prior to malignant degeneration necessitates an aggressive approach to rule out cancer.

Unusual presentation of mucinous adenocarcinoma in a post fistulectomy case

“…Some are associated with Crohn's disease. 5 The occurrence of a carcinoma in association with a fistula is probably due to chronic inflammation, although the rarity of the condition precludes any definite assumption in regard to the etiologic relationship of the fistula and carcinoma. Rossner in 1931 established three essential criteria to confirm that malignant transformation has occurred within a fistula.…”

MR Imaging of Perianal Crohn Disease

“…Strictures can occur anywhere from the anus to the midrectum (24). Malignant transformation is rare, but can occur within chronic perianal fistulas (60,61), and seems to have a female surgical intervention) whereas surgical classification was not (37). Buchanan et al performed preoperative MR imaging in 71 patients with recurrent fistula (56).…”

Imaging techniques and combined medical and surgical treatment of perianal Crohn’s disease

“…On the other hand, if fistulectomy is not performed, this increases the possibility of missing secondary tracts, which, as already mentioned, are considered a risk factor for recurrence and reoperation [31,32]. Moreover, particularly diseases of long duration present the risk of malignant transformation of the fistula [78,79]. For these reasons, the best surgical solution seems to be removal of fistula tracts and the surrounding inflamed Fig.…”

“…Malignant transformation in perianal Crohn's disease is rare (adenocarcinoma is more common than squamous cell carcinoma) [79,132], but diagnosis is often delayed because of the very low sensitivity of MRI, EUS, and CT in identifying neoplastic transformation in an environment of severe chronic inflammation [78,133,134].…”