Molecularly Redefining Small Bowel Adenocarcinoma to Accelerate Precision Patient Care

Small bowel adenocarcinoma (SBA), an orphan cancer, has annual diagnoses of 12,070 in the USA and 100 in Denmark. Despite its rarity, patient management should prioritize evidence-based care, but large trials are not feasible, leading to data scarcity and suboptimal care. As a result, SBA is treated like colorectal cancer, yet its prognosis is worse, indicating this parallel approach is insufficient. The grasp on SBAs molecular landscape is limited compared to prevalent cancers. Scant mutational profiling studies, suggest SBA is a heterogeneous disease where subsets resemble other gastrointestinal cancers. This underscores the potential for personalized treatments, including targeted therapies and immunotherapies. Comprehensive molecular characterization, using DNA, RNA, and T-cell receptor characteristics, can provide much-needed strategic direction for patient care and future trials. Capitalizing on this, the investigators propose a comprehensive molecular characterization aiming to develop consensus molecular subtypes that can direct future trials and SBA therapeutic strategies.

The investigators hypothesize that a consensus molecular profiling approach can identify subgroups of SBA with distinct molecular, cellular, and histological characteristics, that will benefit from tailored treatment strategies using chemotherapy, targeted therapy, and immunotherapy.

To explore this hypothesis, the investigators will: (WP1) perform molecular and immunological characterization of tumor tissues from SBA patients (n=200) to establish consensus molecular subtypes of SBA and define their biological attributes; (WP2) ascertain therapeutic avenues tailored to each subtype and devise a molecular algorithm to prospectively categorize individual tumors in real-time, laying the groundwork for molecularly-driven management.

Inclusion criteria

Patients with histologically verified small bowel adenocarcinoma Patients older than 18 years

Exclusion criteria

Insufficient material for molecular testing Patients registered in Vævsanvendelsesregistret&

Vævsanvendelsesregistret; refers to a central Danish registry where patients can opt out of allowing their biological material to be used for purposes other than their own disease management.