Potential MR Enterography Features to Differentiate Primary Small Intestinal Lymphoma From Crohn Disease

Area of Science:

• Gastroenterology
• Radiology
• Oncology

Background:

• Primary small intestinal lymphoma (PSIL) and active Crohn disease (CD) with severe mural thickening can present with overlapping imaging features.
• Accurate differentiation is crucial for appropriate patient management and treatment.

Purpose of the Study:

• To assess MR enterography features of PSIL.
• To compare these features with active CD with severe mural thickening (≥ 10 mm).
• To identify imaging parameters that can discriminate between PSIL and severe CD.

Main Methods:

• Retrospective analysis of 15 PSIL and 15 severe CD patients.
• Comparison of morphologic, enhancement, and diffusion parameters on MR enterography.
• Calculation of upstream to involved luminal diameter and mural thickness to luminal diameter ratios.
• Development of a predictive morphologic score.

Main Results:

• PSIL patients showed more unifocal disease, circumferential involvement, luminal dilatation, and attenuated folds.
• PSIL patients had less serosal involvement and mesenteric fat infiltration compared to CD.
• Significantly lower upstream to involved luminal diameter and mural thickness to luminal diameter ratios were observed in PSIL.
• A morphologic score achieved 98% accuracy in differentiating PSIL from CD.

Conclusions:

• Morphologic features on MR enterography are more valuable than enhancement or diffusion parameters for differentiating PSIL from severe CD.
• Lower upstream to involved luminal diameter and mural thickness to luminal diameter ratios are characteristic of PSIL.