GI Cancers Symposium 2020: Predicting Risk of Relapse in Colon Cancer With Immunoscore
Posted: Friday, February 7, 2020
Work confirming the Immunoscore’s value in predicting disease-free survival in patients treated for 3 or 6 months with modified FOLFOX6 (fluorouracil, leucovorin, and oxaliplatin) was presented at the 2020 Gastrointestinal (GI) Cancers Symposium in San Francisco (Abstract 10). Franck Pagès, MD, PhD, of Hôpital Européen Georges Pompidou, Paris, and colleagues evaluated the actual versus Immunoscore-predicted outcomes of 1,200 patients with stage III colon cancer in the IDEA France cohort study who were randomly divided to receive the shorter or longer modified FOLFOX6 course.
An Immunoscore is calculated by using a “predefined cutoff” to convert “densities of CD3-positive and cytotoxic CD8-positive T cells in the tumor and invasive margin [that] were determined by immunohistochemistry [and] quantified by digital pathology,” the authors wrote. Low and intermediate/high Immunoscores were assigned to 43.5% and 56.5% of patients, respectively. A low Immunoscore successfully (P < .0001) identified patients at higher risk of relapse or death; their 3-year disease-free survival rate was 66.34%, versus 77.66% in those with an intermediate/high Immunoscore.
Considering treatment length, Dr. Pagès and colleagues found that the 3-year disease-free survival rate of patients with an intermediate/high Immunoscore in the 3-month arm was 71.5%, compared with 83.8% in the 6-month arm (log-rank P = .0004). However, versus 3-month treatment, “6-month modified FOLFOX6 showed no significant benefit for patients with a low Immunoscore (log-rank P = .269),” they noted.
“A statistically significant interaction was observed for Immunoscore’s predictive value for [the impact of] treatment duration (3 vs. 6 months) in terms of disease-free survival in the whole population (P = .0566) and tumor/node subgroups (low-risk T1–3, N1 vs. high-risk T4 and/or N2; P = .0015),” the researchers continued. Possibly Immunoscore would have “predictive value for benefit of longer duration treatment,” they postulated, but it would “[need] to be confirmed in an external validation cohort.”
Disclosure: The study authors’ disclosure information can be found at meetinglibrary.asco.org.