MCL-049: Clinical Characteristics and Outcomes of Primary Versus Secondary Gastrointestinal (GI) Mantle Cell Lymphoma (MCL)

Abstract

Context: While GI involvement in nodal MCL (secondary GI MCL) is thought to be common, primary GI MCL without nodal or other extranodal involvement is rare. The optimal management of primary GI MCL is unclear. Objective: Compare the clinical characteristics and outcomes of primary vs secondary GI MCL. Design: Retrospective study. Setting: Tertiary academic center. Patients or other participants: Patients with newly diagnosed MCL with biopsy-proven GI involvement between 1/1990-2/2018 and seen at Mayo Clinic. Median follow-up was 85 months. Interventions: Management per treating physicians. Main outcome measures: Progression-free survival (PFS) and overall survival (OS). Results: Among 800 patients with newly diagnosed MCL, 22 (2.8%) had primary GI MCL and 79 (9.9%) had secondary GI MCL. Initial presentation of primary GI MCL included single lesion (mucosal, polyp, or mass; n=7), multiple lesions in 1 organ (n=7), and multiple lesions in ≥2 organs (n=8). Age, sex, and ECOG PS were similar between primary and secondary GI MCL. Secondary GI MCL had more LDH elevations (0 vs 20%, p=0.03) and a trend of higher MIPI score (p=0.07). Observation or local therapy were more common for primary GI MCL (29 vs 8%, p Conclusions: Primary and secondary GI MCL had similar outcomes albeit less aggressive treatment in primary cases. Extent of GI involvement in primary GI MCL did not affect outcome. Whether primary GI MCL should be treated the same as secondary GI MCL requires additional studies.