1. Bone Marrow Biopsy Focal involvement by small B-cell neoplasm without significant plasmacytic differentiation (CD3-, CD20+, PAX5+, kappa IHC-, lambda IHC-, CD5-, CD10-, BCL6-, BCL2+, cyclin D1-, IgD-, Ki67 low) Courtesy of T Pongpruttipan, MD.

2. Review of Colonic Polyp Biospy Tissue HE CD20 HE Courtesy of T Pongpruttipan, MD.

3. Final Pathological Diagnosis Involvement by small B-cell lymphoid neoplasm with CD10+, BCL2+, BCL6- phenotype. No evidence of large cell involvement. Some small and large cells showed large aggregates with infiltrative growth pattern. IMP: follicular lymphoma with focus of large cell transformation DDx DLBCL with accompanying follicular lymphoma Follicular lymphoma, grade 3/3 (focal) in the background of follicular lymphoma, low grade

4. Colorectal Lymphoma A type of extranodal lymphoma involving GI tract Primary GI lymphoma Stomach 40-50% Small bowel 20-30% Colon and rectum 10-20% Primary GI lymphoma No palpable, superficial LN No enlarged mediastinal LN on CXR Normal WBC (No and differential count) Only regional LN involved No involvement of liver and spleen Dawson IM, et al. Primary malignant lymphoid tumours of the intestinal tract. Report of 37 cases with a study of factors influencing prognosis. Br J Surg 1961;49:80-9.

5. Staging of Lymphoma

6. Musshoff Modifications to Ann Arbor Staging System for Extranodal Lymphoma Stage I or IESingle lymphatic organ or extranodal site IITwo or more lymphatic regions on the same site of the diaphragm or a single extranodal organ and lymph node involvement at the same site of diaphragm II1Regional lymph node involved II2Distant lymph node involved IIILymph node involved on both sides of diaphragm IVDisseminated disease with involvement of bone marrow, liver, etc Musshoff K. Strahlentherapie 1977;153:218-21. Boot H. Best Pract Res Clin Gastroenterol 2010;24(1):3-12.

7. Common Types in Colorectal NHL DLBCL60% de novo Transformation from CLL, follicular lymphoma, MALT MALT15% Burkitt15 Recent report from Terada T, Japan 37 cases of GI lymphoma M:F 20:17 Median age 69 yr (46- 89) Types Gastric 25 (68%) Small bowel 6 (16%) Colon 6 (16%) Terada T. Gastrointestinal malignant lymphoma: a pathologic study of 37 cases in a single Japanese institution. Am J Blood Res 2012;2(3):194-200.

8. Gastrointestinal Lymphoma Types B-cell35 (95%) T-cell2 (5%) Gastric NHL 25 DLBCL11 MALT14 Small intestine DLBCL4 PTCL2 Colon 6 DLBCL5 FL1 Clinical diagnosis of colon NHL at first GIST1 Colon carcinoma4 Colon polyp1 No cases of Hodgkin lymphoma Burkitt lymphoma Mantle cell lymphom Terada T. Gastrointestinal malignant lymphoma: a pathologic study of 37 cases in a single Japanese institution. Am J Blood Res 2012;2(3):194-200.

9. Primary FL of GI tract: Massachusetts General Hospital, 1995-2010 Excluded cases History of FL outside GI tract Widespread lymphoma Distant nodal disease within 6 months Multifocal diseases Splenic involvement FL in transformation Misdraji J, et al. Primary follicular lymphoma of the gastrointestinal tract. Am J Surg Pathol 2011;35:1255-63.

10. Presenting Symptoms/ Finding Symptoms Abdominal pain and nausea, vomiting (12),  bowel obstruction Intussuspection (1) Incidental finding (13) on investigation of Reflux symptoms or Barrett esophagus Screening for colorectal cancer Resection of sigmoid carcinoma Macroscopic findings White patches or plaques Mucosal nodularity or granularity Nodules Polyp (1, 2, 3) Submucosal mass Thickening of wall or folds Misdraji J, et al. Primary follicular lymphoma of the gastrointestinal tract. Am J Surg Pathol 2011;35:1255-63.