Consensus molecular subtypes of primary colon tumors and their hepatic metastases.

Aim: This pilot study aimed to evaluate the congruency in consensus molecular subtypes (CMS) of primary colorectal cancer and corresponding hepatic metastasis (HM).

Materials & Methods: RNA was extracted from both primary colorectal cancer and HM from ten patients, sequenced to establish gene-expression profiles and classified into CMS. Clinical data were collected retrospectively.

Results: Of the ten patients recruited, nine had primary tumors that were classifiable: seven were CMS2, one was CMS3 and one was CMS4. Five had incongruent classification in the corresponding HM. Three out of the five patients with incongruent classification had received adjuvant chemotherapy prior to hepatic resection.

Conclusion: A change in CMS type between matched primary and metastatic colorectal tumors is common and may be attributable to chemotherapy.