Mucinous adenocarcinoma in perianal fistula in Crohn's disease: Case report and literature review

• Published in: International journal of surgery case reports Vol. 95; p. 107211
• Main Authors: de Souza, Ana Beatriz Pereira, Lima, Amanda Pereira, Genaro, Lívia Moreira, Geiger, Carla Peres Fingerhut, Ayrizono, Maria de Lourdes Setsuko, Leal, Raquel Franco
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01-06-2022; Elsevier
• Subjects: Case Report; Colorectal surgery; Crohn's disease; Mucinous adenocarcinoma; CD; Case report; APR; CRC; Crohn's disease; Mucinous adenocarcinoma; Colorectal surgery; BMI
• ISSN: 2210-2612; 2210-2612
• DOI: 10.1016/j.ijscr.2022.107211

Crohn's disease (CD) is a chronic bowel disease that, due to exacerbated inflammation, can lead to complications such as the development of perianal fistulas. The development of mucinous adenocarcinoma in perianal fistulas in patients with CD is rare and, consequently, few reports exist in the literature.
We report the case of a 71-year-old man diagnosed 22 years ago with CD with perineal involvement, who came with complaints of intense perianal pain, a gluteal mass, and local bleeding. Tomography of his abdomen showed an expansive, heterogeneous, and solid perianal mass on the right, with interspersed necrotic/liquefied areas and possible mucinous content. The patient was referred to the surgery department for an incisional biopsy, which confirmed mucinous adenocarcinoma. The patient underwent extra levator abdominoperineal rectal resection (APR) with partial prostatectomy.
Perineal mucinous adenocarcinoma arising in a fistula associated with CD is very rare. Since the symptoms overlap, early diagnosis of malignancy is difficult. Histological analysis is the gold standard for its diagnosis. Surgical resection through APR is well-established and, despite being a complex procedure with potential complications, tends to have good results. However, the locoregional and inguinal lymph node involvement was related to a worse progression in this case.
The diagnostic hypothesis of mucinous adenocarcinoma should be suspected in CD patients who present long-term perineal involvement with fistulas. Biopsies and imaging exams should be performed to aid the diagnosis of the condition and thus contribute to the surgical plan.
•Mucinous adenocarcinoma in perianal fistulas from CD patients is extremely rare.•Magnetic resonance imaging findings help in Mucinous adenocarcinoma diagnosis.•Locoregional and inguinal lymph node involvement is related to a worse progression.