22
Treatment
Table 2. Gastrointestinal (GI) Toxicities
2.1 Colitis
Workup/Evaluation
G2:
• Work up of blood — CBC, comprehensive metabolic panel (CMP), thyroid-
stimulating hormone (TSH), stool (culture, C. diff, parasite, cytomegalovirus
(CMV) or other viral etiolog y, ova and parasite if appropriate — should be
performed for the initial presentation, and also considered for immunosuppressant
refractory cases.
• Consider testing for fecal lactoferrin (for patient stratification to determine who
needs more urgent endoscopy) and calprotectin (to follow up on disease activity).
• Screening labs (human immunodeficiency virus (HIV), hepatitis A and B, and TB
testing ), repeated annually in patients who require biologic treatment e.g., infliximab
or vedolizumab for >1 year until treatment is completed.
• Consider reviewing concomitant medications that could alter the gut microbiome
and their indications for prolonged use (e.g., proton pump inhibitors, antibiotics,
probiotics, etc.).
• Imaging e.g., computed tomography (CT) scan of abdomen and pelvis for
colitis-related symptoms (abdominal pain, bleeding ) to rule out colitis-related
complications, including typhlitis and bowel perforation/abscess.
• GI endoscopy/colonoscopy with biopsy for patients who have positive stool
inflammatory markers or colitis-related symptoms should be considered as there
is evidence showing the presence of ulceration in the colon can predict steroid
refractory course, which may require early infliximab.
• Repeat colonoscopy may be considered for cases Grade ≥2 for disease activity
monitoring to document complete remission, especially if there is a plan to resume
ICPi. Mucosal healing on repeat endoscopy and/or fecal calprotectin level ≤116µg/g
can be considered the treatment target to guide decisions on when to stop biologic
treatment and when to resume ICPi therapy.
G3–4:
• Complete all recommendations as above and consider in-patient care.
Grading (Based on
CTCAE for diarrhea, as
most oen used clinically) Management
All Patients Counsel all patients to be aware of and inform their
healthcare provider immediately if they experience:
• Abdominal pain, nausea, cramping, blood or mucus in
stool, or changes in bowel habits.
• Fever, abdominal distention, constipation.
• For Grade ≥2, consider permanently discontinuing
CTLA-4 agents and may restart PD-1, PD-L1
agents if patients recover to ≤G1; concurrent
immunosuppressant maintenance therapy should be
considered only if clinically indicated in individual
cases.
