Long-standing Crohn’s disease and its implication on anal squamous cell cancer management.

Abstract

576 Background: Anal squamous cell carcinoma (ASCC) is rare, accounting for 1% of gastrointestinal malignancies, but the incidence is rising. Risk factors for the development of ASCC in patients with Crohn’s disease (CD) include immunotherapy, increased duration of disease, and chronic fistulizing perianal disease. We sought to understand management strategies for ASCC in the setting of CD. Methods: A retrospective review from 2001-2016 was conducted for ICD-9/10 codes pertaining to Crohn’s disease (CD) (555.9/ K50) and ASCC (154.3/C44.520). Adult patients with a diagnosis of CD at the time of ASCC diagnosis were included. Results: A total of 7 patients (5 female) were included with a median age of 50 years. The majority presented with perianal pain (4) and bleeding (3). The mean duration of CD was 20 years, and all patients had perianal disease for > 10 years. Five patients had perianal fistulizing disease at the time of ASCC presentation. Clinical stage at diagnosis of ASCC was stage 0 (n = 1), I (n = 1), II (n = 1), III (n = 2), IV (n = 1), and unknown (n = 1). All patients were treated with Nigro protocol which included radiation (50-55Gy), 5-fluorouracil, and mitomycin; 1 patient received cisplatin due to concurrent Non-Hodgkin’s Lymphoma. Three patients required fecal diversion during radiation due to significant perianal disease. Two patients experienced complications related to radiation including anal and vaginal stenosis and an anovaginal fistula. One additional patient required an APR with rectus abdominis myocutaneous flap for uncontrolled CD after treatment. During follow-up, 3 of the 7 patients undergoing definitive chemoradiation developed residual or recurrent disease and required salvage APR. All patients were alive at last follow-up, 2 with metastatic disease. 5-year disease free survival was 56%. Conclusions: Patients with ASCC in the setting of CD may be managed with the standard Nigro protocol, but complications from radiation are common in this setting. Three of seven patients required salvage surgery for residual or recurrent disease, and an additional patient required APR for palliation of CD symptoms. Given the aggressive nature of ASCC in this population, surveillance guidelines are necessary.