E0356 - Immune Checkpoint Inhibitors for Colorectal Cancer in Patients With Inflammatory Bowel Disease

Tuesday, October 25, 2022

3:00 PM – 5:00 PM ET

Location: Crown Ballroom

Presenting Author(s)

DF

David M. Faleck, MD

Memorial Sloan Kettering Cancer Center
New York, NY

David M. Faleck, MD¹, Konika Sharma, MD², Rona Yaeger, MD², David Kelsen, MD²
¹Memorial Sloan Kettering Cancer Center, New York, NY; ²Memorial Sloan Kettering Cancer Institute, New York, NY

Introduction: Immune checkpoint inhibitors (ICIs) have revolutionized the management of many types of malignancies, including microsatellite instability high (MSI-H) colorectal cancers (CRC), but pose a unique challenge to patients with underlying inflammatory disorders such as inflammatory bowel disease (IBD). The safety and efficacy of ICI therapy for CRC in patients with underlying IBD has not been described.

Methods: We queried the electronic health database for patients with IBD and CRC who were treated with ICI at tertiary care cancer center in New York City. We collected demographic data, IBD and cancer history, and outcomes of both IBD and CRC after treatment with ICIs.

Results: Four patients with underlying IBD were treated with ICIs for MSI-H colorectal cancer (Table 1). All patients had long-standing IBD for greater than 20 years. Two of the patients were diagnosed with concomitant Lynch syndrome at the time of MSI-H cancer diagnosis. No patients were on active IBD therapies at the time of ICI initiation. All four patients were treated with anti-PD-1 therapy (Pembrolizumab) for stage 3 (n=2) or stage 4 (n=2) CRC. All four patients had robust cancer responses to ICI, three with partial responses and one with a complete response over a median follow-up time of 34 months. One patient with locally advanced rectal cancer had a complete response and has avoided the need for surgical resection and permanent stoma.Three patients had a flare of IBD while on ICI requiring initiation of 5-ASA (n=2) or immunosuppressive therapy (n=1) (Table 1). One patient required hospitalization for IBD flare. ICI therapy was held due to IBD flare for two patients who had already achieved significant response to ICI with stable disease.

Discussion: In this small series of patients with IBD and MSI-H colorectal cancer, treatment with ICIs was effective at achieving cancer response in all patients while IBD flares were common but manageable with standard medical therapy. Larger studies are needed to explore the safety and efficacy of ICIs for CRC in patients with IBD.

Patient	Age of ICI Initiation & IBD type	IBD Duration (years) & Prior IBD Medications	Lynch Syndrome	Cancer Stage	ICI Type & Doses of ICI	Treatment for IBD Flare	Best overall Cancer Response to ICI	Surgery for CRC
1	51, Crohn's	38; SSZ, CS, IFX	No	IV	PD- 1, 33	Prednisone, Adalimumab, Ustekinumab	Partial Response	Subtotal colectomy (before ICI)
2	50, Crohn's	23; 6-MP	No	IV	PD- 1, 10	N/A	Partial Response	Total proctocolectomy with end ileostomy (before ICI)
3	35, UC	22; 5-ASA	Yes	III	PD- 1, 33	5-ASA	Complete Response	None
4	34, UC	22; 5-ASA, CS,AZA	Yes	III	PD- 1, 4	5-ASA	Partial Response	Total proctocolectomy with ileoanal anastomosis (after ICI)

ADA: adalimumab, AZA: azathioprine; CRC- Colorectal Cancer; CS: corticosteroids; CTCAE: Common Terminology Criteria for Adverse Events, IBD: inflammatory bowel disease, ICI: immune checkpoint inhibitor; IFX: infliximab; PD-1: Programmed Death 1; SSZ: sulfasalazine; 5-ASA: 5-aminosalicylate; 6- MP : 6-mercaptopurine; UC: ulcerative colitis

Table: Table 1: Baseline Characteristics and Outcomes of CRC and IBD after ICI Therapy.

Disclosures:

David M. Faleck: AzurRx Biopharma – Advisory Committee/Board Member. Equillium – Advisory Committee/Board Member. Kaleido Biosciences – Advisor or Review Panel Member. Mallinckrodt Pharmaceuticals – Advisory Committee/Board Member.

Konika Sharma indicated no relevant financial relationships.

Rona Yaeger: Boehringer Ingelheim – Grant/Research Support. Mirati Therapeutics – Advisor or Review Panel Member, Grant/Research Support. Pfizer – Grant/Research Support.

David Kelsen: Aummune – Provision of services. Daiichi sankyo – Provision of services. Incyte – Provision of services. Merck Sharp & Dohme – Provision of services. Steba Biotechnology – Provision of services.

David M. Faleck, MD¹, Konika Sharma, MD², Rona Yaeger, MD², David Kelsen, MD². E0356 - Immune Checkpoint Inhibitors for Colorectal Cancer in Patients With Inflammatory Bowel Disease, ACG 2022 Annual Scientific Meeting Abstracts. Charlotte, NC: American College of Gastroenterology.