Molecular evidence links lymphomatous polyposis of the gastrointestinal tract with mantle cell lymphoma

Lymphomatous polyposis of the gastrointestinal tract, including mantle cell lymphoma, follicular lymphoma and mucosa-associated lymphoid tissue lymphoma

AIMS

Lymphomatous polyposis (LP) is considered to represent mantle cell lymphoma (MCL) of the gastrointestinal (GI) tract. However, a few reports have suggested that some are follicular lymphoma (FL) or mucosa-associated lymphoid tissue (MALT) lymphomas. In this study, we analysed 35 patients and clarified the clinicopathological features of LP.

METHODS AND RESULTS

Paraffin-embedded tissue samples were stained immunohistochemically and analysed by tissue-fluorescence in situ hybridization (T-FISH) for IGH/CCND1 (cyclin D1) and IGH/BCL2. The average age of the patients was 58.3 years. Over half of the cases showed gastric, duodenal, small intestinal, ileocaecal and sigmoid colonic lesions (15, 19, 15, 16 and 16 cases, respectively). Phenotypically, cases were classified into three types of MCL (cyclin D1+ CD5+ CD10-) (n=12), FL (cyclin D1- CD5- CD10+) (n=14) and MALT (cyclin D1- CD5- CD10-) (n=9). T-FISH identified 11 of the 11 examined cases with MCLs to have IGH/CCND1, while seven of 10 cases with FL had IGH/BCL2, and none of the MALT cases were positive for IGH/CCND1 or IGH/BCL2. At the study endpoint, five of 12 patients with MCL were dead, two of 14 with FL and one of nine with MALT were dead of other disease. Event-free survival analysis showed significantly poorest outcome in MCL, followed by FL, while MALT was associated with a favourable outcome (P=0.0040).

CONCLUSIONS

Our study emphasizes the importance of differentiating MCL, FL and MALT of LP in evaluating prognosis and hence the most suitable therapeutic regimen.

Synchronous adenocarcinoma and mantle cell lymphoma of the colon

Synchronous occurrence of malignant lymphoma and carcinoma, both located in the intestinal tract, is unusual. We report a unique case of an adenocarcinoma of the cecum and a simultaneous mantle cell lymphoma of the colon, terminal ileum, and regional lymph nodes in an 85-year-old man. Grossly, the adenocarcinoma was identified as a cecal mass. Lymphomatous involvement of the gastrointestinal tract was evident only on microscopic examination. The terminal ileum and colon showed microscopic disseminated multiple mucosal nodules, with involvement of the regional lymph nodes. There was no involvement of distant organs, suggesting that the mantle cell lymphoma was early in its evolution without formation of polyps or a mass lesion. To our knowledge, this is the fourth reported case with this association and the second case that showed early involvement of the gastrointestinal tract with mantle cell lymphoma without polyp formation.

The evaluation of the biological behavior and grade among cases with mantle cell lymphoma

We have studied the expression of MIB-1 and prognosis in cyclin D1(CyD1)+ and CyD1- mantle cell lymphoma (MCL), and compared them to B-CLL/SLL. All cases were assigned to four groups by immunoreactivity and primary sites: (1) CyD1+ nodal MCL, 11 cases: (2) CyD1+ extranodal MCL (multiple lymphomatous polyposis, (MLP)) three cases: (3) CyD1- nodal MCL, three cases: and (4) CyD1- B-CLL/SLL, seven cases. The average of MIB-1 labeling indexes of the four groups were 30.66, 8.70, 9.30 and 4.66, respectively. The CyD1- group consisting of nodal MCL and CLL/SLL had a significantly longer median survival time (69 months) than the CyD1+ group consisting of nodal MCL and MLP (22 months, P = 0.01). These data indicate that CyD1- nodal MCL may show a lower MIB-1 labeling index, and has a better prognosis, than CyD1+ nodal MCL. In addition, a large difference in the average of MIB-1 labeling indexes between nodal MCL and MLP in the CyD1+ group was found.

Endoscopic ultrasonography in multiple lymphomatous polyposis

Two cases of multiple lymphomatous polyposis (MLP) are presented, involving different segments of the gastrointestinal tract. Both cases display the characteristic clinical and pathologic features of MLP. In addition, we were able to document, for the first time, the endoscopic ultrasonographic findings in this disease. This new ancillary diagnostic technique was found to be very helpful in the evaluation of the structural changes of the wall of the gastrointestinal tract and in the detection of affected lymph nodes.

Multiple lymphomatous polyposis of the gastrointestinal tract is a heterogenous group that includes mantle cell lymphoma and follicular lymphoma: analysis of somatic mutation of immunoglobulin heavy chain gene variable region

Multiple lymphomatous polyposis (MLP) is characterized by multiple polyps involving long segments of the gastrointestinal (GI) tract. MLP is thought to represent mantle cell lymphoma (MCL) of the GI tract; however, some cases of follicular lymphoma (FL) of the GI tract are found with a multiple polypoid appearance. In the present study, to clarify the cellular origin of MLP, clonal immunoglobulin heavy chain (IgH) gene rearrangement of four cases with MLP was amplified by polymerase chain reaction (PCR) and analyzed for the presence of somatic mutation. The IgH variable (VH) region sequences of three cases (CD5+ CD10- cyclin D1+) showed a little somatic mutation compared with the closest published germline. The other case (CD10+ CD5- cyclin D1-) was highly mutated and showed intraclonal heterogeneity (ongoing somatic hypermutation). These data indicate that three of the cases with MLP are derived from pregerminal center B cells (mantle zone B cells) and one case with MLP from germinal center B cells. Our study suggests that MLP is a heterogenous group that includes MCL and FL.