RT Journal Article
SR Electronic
T1 Recommendations for standardizing biopsy acquisition and histological assessment of immune checkpoint inhibitor-associated colitis
JF Journal for ImmunoTherapy of Cancer
JO J Immunother Cancer
FD BMJ Publishing Group Ltd
SP e004560
DO 10.1136/jitc-2022-004560
VO 10
IS 3
A1 Christopher Ma
A1 Rish K Pai
A1 David F Schaeffer
A1 Jonathan Krell
A1 Leonardo Guizzetti
A1 Stefanie C McFarlane
A1 John K MacDonald
A1 Won-Tak Choi
A1 Roger M Feakins
A1 Richard Kirsch
A1 Gregory Y Lauwers
A1 Reetesh K Pai
A1 Christophe Rosty
A1 Amitabh Srivastava
A1 Joanna C. Walsh
A1 Brian G Feagan
A1 Vipul Jairath
YR 2022
UL http://jitc.bmj.com/content/10/3/e004560.abstract
AB Immune checkpoint inhibitor-associated colitis (ICIC) affects approximately 15% of cancer patients treated with immunotherapy. Although histological evaluation is potentially valuable for both the diagnosis of ICIC and evaluation of disease activity, use in clinical practice is heterogeneous. We aimed to develop expert recommendations to standardize histological assessment of disease activity in patients with ICIC. Using the modified Research and Development/University of California Los Angeles (RAND/UCLA) appropriateness methodology, an international panel of 11 pathologists rated the appropriateness of 99 statements on a 9-point Likert scale during two rounds of anonymous voting. Results were discussed between rounds using moderated videoconferences. There are currently no disease-specific instruments for assessing histological features of ICIC. The panel considered that colonoscopy with at least three biopsies per segment from a total of at least five segments, including both endoscopically normal and inflamed areas, was appropriate for tissue acquisition. They agreed that biopsies should be oriented such that the long axis of the colonic crypts is visualized and should be stained with hematoxylin and eosin. Histological items that the panel voted were appropriate to evaluate in ICIC included the degree of structural/architectural change, chronic inflammatory infiltrate, lamina propria and intraepithelial neutrophils, crypt abscesses and destruction, erosions/ulcerations, apoptosis, surface intraepithelial lymphocytosis, and subepithelial collagen thickness. The appropriateness of routine immunohistochemistry was uncertain. These expert recommendations will help standardize assessment of histological activity in patients with ICIC. The panel also identified the development and validation of an ICIC-specific histological index as a research priority.