Gastric follicular lymphoma: A report of 3�cases and a review of the literature

Abstract

Follicular lymphoma (FL) occurs primarily in the gastrointestinal tract, with the stomach being one of the rarest sites. According to the literature, <20 cases of primary gastric FL have been reported, with the number of cases with detailed pathological descriptions being even less. The aim of the present study was to compare clinicopathological features of gastric FL with FL at alternative sites. A total of 3 cases of gastric FL were retrieved from among 3,216 cases in the databases of 4 university hospitals in South Korea: Seoul National University (SNU) Hospital, SNU Boramae Hospital, SNU Bundang Hospital (all Seoul, South Korea) and Dongtan Sacred Heart Hospital Hallym University (Dongtan, South Korea), including 2 primary cases and 1 case that was possibly secondary to nodal FL. The 2 primary gastric FL cases were incidentally detected in routine health check-ups. An endoscopy revealed a single polypoid submucosal mass and biopsies failed to confirm the diagnosis due to minimal mucosal involvement. Therefore, a partial gastrectomy was performed. The epicenters of the tumors were submucosal, with focal extension to the muscularis propria. However, 1 case exhibited an isolated FL nodule in the omentum. Histopathological examination revealed FL of grade 1–2 with a follicular pattern and with strong expression of germinal center markers and B-cell lymphoma 2 (BCL2). Rearrangement of BCL2 was not identified using fluorescence in situ hybridization studies in 2 cases. In contrast to these 2 cases, the remaining FL case was confirmed with an endoscopic biopsy. The endoscopy revealed multiple eroded polypoid lesions, and pathology revealed FL of grade 1–2 with a predominantly diffuse pattern, and with immunoglobulin heavy chain IGH/BCL2 translocation. In view of the extensive lymphadenopathy, the last case possibly presented as secondary involvement of nodal FL. It is challenging to diagnose FL in the stomach due to little mucosal involvement, as well as the unfamiliarity of the tumor due to its rarity. However, the results of the present study suggest that primary gastric FL may exhibit unique pathological features, including a predominantly follicular pattern and an absence of BCL2 rearrangement.

Primary Gastrointestinal Follicular Lymphomas: A Prospective Study of 31 Patients with Long-term Follow-up Registered in the French Gastrointestinal Lymphoma Study Group (GELD) of the French Federation of Digestive Oncology (FFCD)

“…Primary gastrointestinal follicular lymphomas (PGFL) represent a very rare entity, whose frequency in different clinicopathological series of primary gastrointestinal lymphomas varied from 3% to 13%. [1][2][3][4] The clinical and biological characteristics of these Primary Gastrointestinal Follicular Lymphomas: A Prospective Study of 31 Patients with Long-term Follow-up Registered in the French Gastrointestinal Lymphoma Study Group (GELD) of the French Federation of Digestive Oncology (FFCD) lymphomas are not well known, and have been described mainly through clinical cases [5][6][7][8][9] and some clinicopathological series, usually retrospective, reported in the literature. [10][11][12][13][14][15][16][17][18] Due to their rarity and lack of randomized trials, the treatment of PGFL is not standardized.…”

Underwater endoscopic mucosal resection of a follicular lymphoma

“…Most reported cases of primary gastric FL presented with a localized disease and single or multiple submucosal tumors. [ 2 ] Gastric FL presenting as SET is uncommon and its incidence rate has not been reported. [ 1 ] A primary gastric FL may be misdiagnosed as an extra-nodal marginal zone B-cell lymphoma on biopsy specimens.…”

“…[ 1 ] A primary gastric FL may be misdiagnosed as an extra-nodal marginal zone B-cell lymphoma on biopsy specimens. [ 2 ] The overlying normal mucosa over the FL presenting as a SET could hinder the accurate diagnosis through endoscopic mucosal biopsy. Most small SETs covered with normal mucosa are identified during periodic endoscopic follow-up.…”

“…Since primary gastrointestinal FLs mostly appear as subepithelial tumors (SETs), endoscopic forceps biopsies are often inconclusive. [ 2 ]…”

Gastrointestinal Tract Lymphomas

“…38,39 Follicular Lymphoma Gastric FL is rare, with a reported incidence of 0.8% to 3.6% of gastric lymphomas. 40,41 Thus, owing to the low incidence of primary gastric FL, emphasis should be placed on clinical staging to exclude secondary involvement by a systemic process. FL of the GI tract is discussed in detail in the small intestine section.…”