Case Example 14 (Number of Primaries)

Patient diagnosed with stage 4 pancreatic cancer in 2021, still receiving FOLFIRI every 2 weeks since

  • Pt was then diagnosed with marginal zone b-cell lymphoma 08/03/2022), no treatment was recommended for this lymphoma (patient still receiving FOLFIRI at this time).
  • Patient was then diagnosed with DLBCL on liver biopsy 05/21/2024, also in bone marrow biopsy 05/24/24. No treatment given for the DLBCL.  
  • Patient then has a SCV lymph node bx 10/30/24 that is positive for follicular lymphoma, grade 1-2.

This scenario requires going through the rules multiple times.

Primary Rule Comments
1. Pancreatic cancer N/A Solid Tumor Rules applicable
2. Marginal zone lymphoma (MZL) If you have a solid tumor (8000-9582) and a hematopoietic tumor (9590-9993), these are automatically 2 primaries M2: Single histology, single primary
3. Diffuse large B-cell lymphoma (DLBCL) This is a case of transformation per the Heme DB. MZL can transform to DLBCL M10: Chronic neoplasm (MZL) followed by an acute neoplasm (DLBLC)
Follicular lymphoma (not a new primary) This is a case of transformation per the Heme DB. DLBCL (acute) reverting back to a chronic neoplasm, the follicular lymphoma M12: Acute neoplasm followed by chronic with no treatment or unknown if treatment
Per Rule M12, this would be the same primary, which is the DLBLC

This patient has 3 primaries

Updated: December 2, 2025