A 55-year-old man with gastric MALT lymphoma is H. pylori positive on biopsy. Which cytogenetic finding predicts failure of response to H. pylori eradication therapy and indicates a need for systemic treatment?

• A Trisomy 3
• B t(14;18)(q32;q21) involving IGH and BCL2
• C del(13q14)
• D t(11;18)(q21;q21) producing API2-MALT1 fusion ✓

Explanation

The t(11;18)(q21;q21) translocation creates the API2-MALT1 fusion transcript, which activates NF-kappaB independent of antigenic stimulation. Such tumors are genetically driven and characteristically do not regress after antibiotic eradication of H. pylori, so first-line antibiotics fail. Trisomy 3 and trisomy 18 are common but do not preclude antibiotic response, and BCL2 rearrangement belongs to follicular lymphoma, not gastric MALT lymphoma.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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