Primary gastrointestinal follicular lymphoma involving the duodenal second portion is a distinct entity: a multicenter, retrospective analysis in Japan

Duodenal-type follicular lymphoma: comprehensive insights into disease characteristics and established treatment strategies

PURPOSE OF REVIEW

This review aims to detail the characteristics and outcomes of duodenal-type follicular lymphoma (DTFL), a rare lymphoma variant. It focuses on integrating recent reports in treatment modalities and highlights emerging insights into the unique biological features of the disease.

RECENT FINDING

Recent studies confirm the indolent nature of DTFL, with extended follow-up periods showing favorable outcomes under watchful waiting strategies and a notable proportion of patients experiencing spontaneous remission. Additionally, advancements in understanding the disease's biology revealed that the tumor microenvironment is marked by specific genomic expressions indicative of chronic inflammation.

SUMMARY

The observations of spontaneous resolution and the generally favorable progression of DTFL call for a conservative approach in initiating treatment. Clinical management should judiciously consider the disease's typically benign course against the potential risks of intervention, promoting customized treatment protocols tailored for cases with clinical necessity. Additionally, the discovery of an inflammatory tumor microenvironment and molecular evidence suggesting an antigen-driven process highlight critical areas for future research.

Epidemiological features and prognosis for primary gastrointestinal follicular lymphoma

Primary gastrointestinal follicular lymphoma (PGI-FL) is a rare extra-nodal lymphoma. Its epidemiology and prognosis remain unclear. We performed a retrospective analysis of eligible patients with 1648 PGI-FL and 34 892 nodal FL (N-FL) in the Surveillance, Epidemiology and End Results (SEER) database. The age-adjusted average annual incidence of PGI-FL was 0.111/100000. The median overall survival (OS) for PGI-FL and N-FL patients was 207 and 165 months respectively. The 5-year diffuse large B-cell lymphoma (DLBCL) transformation rates were 2.1% and 2.6% respectively. Age, sex, grade, Ann Arbor stage, primary site and radiation were independent prognostic factors (p < 0.05). Nomograms were constructed to predict 1-, 5- and 10-year OS and disease-specific survival (DSS). The receiver operating characteristic curves and calibration plots showed the established nomograms had robust and accurate performance. Patients were classified into three risk groups according to nomogram score. In conclusion, the incidence of PGI-FL has increased over the past 40 years, and PGI-FL has a better prognosis and a lower DLBCL transformation rate than N-FL. The nomograms were developed and validated as an individualized tool to predict survival. Patients were divided into three risk groups to assist clinicians in identifying high-risk patients and choosing the optimal individualized treatments.

[Studies on clinicopathological features of duodenal-type follicular lymphoma of 18 patients]

To investigate the clinical and pathological characteristics of duodenal-type follicular lymphoma (D-FL), and to deepen the understanding of Duodenal-type follicular lymphoma. The clinical symptoms, endoscopic features, pathologic features, immunophenotype, molecular pathological features and treatment follow-up of 18 D-FL patients diagnosed in Department of Pathology, Beijing Tiantan Hospital affiliated to Capital Medical University between January 2020 and July 2023 were summarized. A total of 18 patients with D-FL were included, including 10 males and 8 females. The median age was 49 (32-69) years respectively. Most of the patients were found during gastroenteroscopy or presented with the common gastrointestinal symptoms of stomach pain, acid reflux, vomiting and diarrhea. Most endoscopic findings were multiple small gray and white polyposis. In the pathological morphology, the mucous layer and submucous layer showed lymphoid follicular structures with full and strained follicles. The immunophenotype showed that the tumor cells strongly expressed CD20 and BCL2 and had low proliferation activity. Immunoglobulin clonal analysis of 1 case showed IgK monoclonal rearrangement (1/1). FISH showed 1 case of BCL2 gene rearrangement (1/3). All patients did not receive targeted chemotherapy and adopted a wait-and-see strategy. Median follow-up was 12 (2-34) months. This study shows that D-FL is an indolent lymphoma, which tends to occur in the duodenum and has a good prognosis.

Frequent CDKN2B/P15 and DAPK1 methylation in duodenal follicular lymphoma is related to duodenal reactive lymphoid hyperplasia

Duodenal type follicular lymphoma (DFL), a rare entity of follicular lymphoma (FL), is clinically indolent and is characterized by a low histological grade compared with nodal follicular lymphoma (NFL). Our previous reports revealed that DFL shares characteristics of both NFL and mucosa-associated lymphoid tissue (MALT) lymphoma in terms of clinical and biological aspects, suggesting its pathogenesis may involve antigenic stimulation. In contrast to NFL, the genomic methylation status of DFL is still challenging. Here, we determined the methylation profiles of DNAs from patients with DFL (n = 12), NFL (n = 10), duodenal reactive lymphoid hyperplasia (D-RLH) (n = 7), nodal reactive lymphoid hyperplasia (N-RLH) (n = 5), and duodenal samples from normal subjects (NDU) (n = 5) using methylation specific PCR of targets previously identified in MALT lymphoma (CDKN2B/P15, CDKN2A/P16, CDKN2C/P18, MGMT, hMLH-1, TP73, DAPK, HCAD). DAPK1 was frequently methylated in DFL (9/12; 75%), NFL (9/10; 90%), and D-RLH (5/7; 71%). CDKN2B/P15 sequences were methylated in six DFL samples and in only one NFL sample. Immunohistochemical analysis showed that p15 expression inversely correlated with methylation status. Genes encoding other cyclin-dependent kinase inhibitors (CDKN2A/P16, CDKN2C/P18) were not methylated in DFL samples. Methylation of the genes of interest was not detected in DNAs from D-RLH, except for DAPK1, and the difference in the extent of methylation between NDU and D-RLH was statistically significant (P = 0.013). Our results suggest that D-RLH serves as a reservoir for the development of DFL and that methylation of CDKN2B/P15 plays an important role in this process.

Disease surveillance evaluation of primary small-bowel follicular lymphoma using capsule endoscopy images based on a deep convolutional neural network (with video)

BACKGROUND AND AIMS

Capsule endoscopy (CE) is useful in evaluating disease surveillance for primary small-bowel follicular lymphoma (FL), but some cases are difficult to evaluate objectively. This study evaluated the usefulness of a deep convolutional neural network (CNN) system using CE images for disease surveillance of primary small-bowel FL.

METHODS

We enrolled 26 consecutive patients with primary small-bowel FL diagnosed between January 2011 and January 2021 who underwent CE before and after a watch-and-wait strategy or chemotherapy. Disease surveillance by the CNN system was evaluated by the percentage of FL-detected images among all CE images of the small-bowel mucosa.

RESULTS

Eighteen cases (69%) were managed with a watch-and-wait approach, and 8 cases (31%) were treated with chemotherapy. Among the 18 cases managed with the watch-and-wait approach, the outcome of lesion evaluation by the CNN system was almost the same in 13 cases (72%), aggravation in 4 (22%), and improvement in 1 (6%). Among the 8 cases treated with chemotherapy, the outcome of lesion evaluation by the CNN system was improvement in 5 cases (63%), almost the same in 2 (25%), and aggravation in 1 (12%). The physician and CNN system reported similar results regarding disease surveillance evaluation in 23 of 26 cases (88%), whereas a discrepancy between the 2 was found in the remaining 3 cases (12%), attributed to poor small-bowel cleansing level.

CONCLUSIONS

Disease surveillance evaluation of primary small-bowel FL using CE images by the developed CNN system was useful under the condition of excellent small-bowel cleansing level.

Diffuse large B-cell lymphoma from duodenal with hematemesis, melena, and obstruction jaundice symptoms: A rare case

INTRODUCTION

Non-Hodgkin lymphoma of the duodenum with manifestation of hematemesis, melena, and obstructive jaundice is a rare occurrence.

CASE PRESENTATION

A 47-year-old Indonesian man presented with symptoms of hematemesis of 3×/day, melena, abdominal pain, decreased appetite, and a weight loss (2 kg). The patient had symptoms of weakness, jaundice, pale conjunctiva, and experienced palpable discomfort in the epigastric region (VAS of 6). An abdominal ultrasonography revealed a heterogeneous cystic tumor mass measuring 45 × 29 mm located in the pancreas head. The gastrointestinal endoscopy revealed erosive gastritis and a tumor in the duodenum. The patient received a biliodigestive surgery and biopsy for double bypass. The pathological anatomy findings indicated the presence of non-Hodgkin lymphoma. The immunohistochemical results showed that the tumor cells were positive for CD45, CD20, and Ki67 95 % but negative for CK and CD3. The patient had a series of chemotherapy treatments include RCHOP, ICE, and EPOCH for a duration of 1½ years. Subsequently, the patient was assessed and pronounced to be cured.

DISCUSSION

The identification of diffuse large B-cell lymphoma (DLBCL) from duodenum in this case was challenging due to the presence of unspecific symptoms such as hematemesis, melena, and obstructive jaundice. Management of DLBCL involved surgical interventions and sequential chemotherapy, which have shown the most significant enhancement in prognosis.

CONCLUSION

The diagnostic accuracy of DLBCL from duodenal site enhances the effectiveness of the therapy employed, leading to a favorable prognosis.

Endoscopic and Histopathological Characteristics of Gastrointestinal Lymphoma: A Multicentric Study

Background: Extranodal non-Hodgkin lymphoma (NHL) is more prevalent in the gastrointestinal (GI) tract than in other sites. This study aimed to determine the endoscopic characteristics of primary gastrointestinal non-Hodgkin lymphomas. Methods: We investigated 140 patients from three tertiary referral hospitals with primary malignant lymphoma of the gastrointestinal tract. Characteristics of the lesions were evaluated and analyzed using image-enhanced endoscopy, endoscopic ultrasound, and histopathology. Results: The median age was 60.5 (range: 11-99), and 59 (42.1%) were female. The most frequent complaint was abdominal pain (74.3%), followed by bloody feces (10%) and diarrhea (2.9%). B symptoms were observed in 15 (10.7%) patients. GI obstruction was the most common complication (10.0%), followed by hemorrhage (7.9%) and perforation (1.5%). Regarding endoscopic findings, the identified sites were the following: the stomach (61.4%), colon (10%), small intestine (10%), ileocecum (8.6%), rectum (6.4%), and duodenum (3.6%). Diffuse large B-cell lymphoma (DLBCL) and mucosa-associated lymphoid tissue (MALT) lymphoma are most prevalent in the stomach. Helicobacter pylori was identified in 46 cases (39.0%), with MALT lymphoma being the most infected subtype. Nearly all gastrointestinal non-Hodgkin lymphomas manifested as superficial type (25-59.6%) and ulcer type (15.6-50%) under endoscopy. We found that fungating type and protruding with ulcer type were more frequent types of aggressive lymphomas (diffuse large B-cell lymphoma, mantle cell lymphoma, and T-cell lymphoma) compared to the indolent types (MALT lymphoma, follicular lymphoma, duodenal-type follicular lymphoma, and small lymphocytic lymphoma) (p < 0.05). Conclusions: This study showed that most subtypes of gastrointestinal non-Hodgkin lymphomas exhibited same endoscopic features (superficial type and ulcer type). Aggressive gastrointestinal non-Hodgkin lymphomas (diffuse large B-cell lymphoma, mantle cell lymphoma, and T-cell lymphoma) were highly suspected when fungating lesions and protruding with ulcer lesions were encountered under endoscopy. Endoscopists should be aware of the connection between enhanced endoscopic characteristics and histological varieties of gastrointestinal lymphoma to improve diagnosis.

Recent advances in treatment of nodal and gastrointestinal follicular lymphoma

Follicular lymphoma (FL) is the most common low-grade lymphoma, and although nodal FL is highly responsive to treatment, the majority of patients relapse repeatedly, and the disease has been incurable with a poor prognosis. However, primary FL of the gastrointestinal tract has been increasingly detected in Japan, especially due to recent advances in small bowel endoscopy and increased opportunities for endoscopic examinations and endoscopic diagnosis. However, many cases are detected at an early stage, and the prognosis is good in many cases. In contrast, in Europe and the United States, gastrointestinal FL has long been considered to be present in 12%-24% of Stage-IV patients, and the number of advanced gastrointestinal cases is expected to increase. This editorial provides an overview of the recent therapeutic advances in nodal FL, including antibody-targeted therapy, bispecific antibody therapy, epigenetic modulation, and chimeric antigen receptor T-cell therapy, and reviews the latest therapeutic manuscripts published in the past year. Based on an understanding of the therapeutic advances in nodal FL, we also discuss future possibilities for gastroenterologists to treat gastrointestinal FL, especially in advanced cases.

Navigating the Heterogeneity of Follicular Lymphoma and its Many Variants: An Updated Approach to Diagnosis and Classification

Follicular lymphoma (FL) is a lymphoid neoplasm composed of follicle center (germinal center) B cells, with varying proportions of centrocytes and centroblasts, that usually has a predominantly follicular architectural pattern. Over the past decade, our understanding of FL has evolved significantly, with new recognition of several recently defined FL variants characterized by distinct clinical presentations, behaviors, genetic alterations, and biology. This manuscript aims to review the heterogeneity of FL and its variants, to provide an updated guide on their diagnosis and classification, and to describe how approaches to the histologic subclassification of classic FL have evolved in current classification schemes.

Clinicopathological characteristics and prognostic factors of small bowel lymphomas: a retrospective single-center study

Background

There is little information on diagnosis and management of small bowel lymphomas, and optimal management strategies are still undefined. This study aims to describe their main clinical and pathological characteristics and identify poor prognostic factors.

Methods

A retrospective observational study of all patients with histological diagnosis of small bowel lymphoma between January 2010 and December 2020 was performed.

Results

We included 40 patients, with male predominance (60%) and mean age of 60.7 years. The ileum was the most common location, and the most common histological subtypes were follicular lymphoma and diffuse large B-cell lymphoma. Clinical presentation was variable from asymptomatic patients (30%) to acute surgical complications (35%) including perforation, intestinal obstruction, ileal intussusception, or severe bleeding. Diagnosis was established by endoscopy in 22 patients (55%), and the most common findings included polyps, single mass, diffuse infiltration, or ulceration, whereas 18 (45%) required surgery because of acute presentations or tumor resection, and lymphoma was diagnosed postoperatively. Surgery was curative in one-third of those patients. Median survival was 52 months. Acute presentation (P = 0.001), symptomatic disease (P = 0.003), advanced stage (P = 0.008), diffuse large B-cell lymphoma (P = 0.007), anemia (P = 0.006), hypoalbuminemia (P < 0.001), elevated lactate dehydrogenase (P = 0.02), elevated C-reactive protein (P < 0.001), and absence of treatment response (P < 0.001) were significant predictors of mortality.

Conclusion

Small bowel lymphoma is a rare malignancy with diverse clinical and endoscopic presentations that require a high index of suspicion. Primary factors associated with worse outcome included acute presentation, advanced stage, histological subtype, biochemical abnormalities, and absence of treatment response.

Long-term outcomes of patients with primary intestinal follicular lymphoma managed with watch-and-wait strategy

Patients with primary intestinal follicular lymphoma are often followed-up without a specific treatment, and this approach is called the "watch-and-wait approach." However, the long-term outcomes of this patient group have not been sufficiently investigated. We enrolled patients with primary intestinal follicular lymphoma who were diagnosed before 2016 and managed with the watch-and-wait approach in 20 institutions. We retrospectively investigated the overall, disease-specific, and event-free survival rates as well as the rate of spontaneous regression. Among the 248 patients with follicular lymphoma with gastrointestinal involvement, 124 had localized disease (stage I or II₁). We analyzed the data of 73 patients who were managed using the watch-and-wait approach. During the mean follow-up period of 8.3 years, the follicular lymphoma had spontaneously resolved in 16.4% of the patients. The 5-year and 10-year overall survival rates were 92.9% and 87.1%, respectively. With disease progression (n = 7), initiation of therapy (n = 7), and histologic transformation to aggressive lymphoma (n = 0) defined as events, the 5-year and 10-year event-free survival rates were 91.1% and 86.9%, respectively. No patient died of progressive lymphoma. Thus, both 5-year and 10-year disease-specific survival rates were 100%. In conclusion, an indolent long-term clinical course was confirmed in the patients with primary intestinal follicular lymphoma. The watch-and-wait strategy is a reasonable approach for the initial management of these patients.

Follicular Lymphoma in the 5th Edition of the WHO-Classification of Haematolymphoid Neoplasms-Updated Classification and New Biological Data

The conceptual description of Follicular lymphoma (FL) in the 5th edition of the World Health Organization (WHO) classification of haematolymphoid tumors (WHO-HAEM5) has undergone significant revision. The vast majority of FL (85%) with a follicular growth pattern are composed of centrocytes and centroblasts, harbor the t(14;18)(q32;q21) translocation and are now termed classic FL (cFL). They are set apart from three related subtypes, FL with predominantly follicular growth pattern, FL with unusual cytological features (uFL) and follicular large B-cell lymphoma (FLBCL). In contrast to the revised 4th edition of the WHO classification of haematolymphoid tumors (WHO-HAEM4R), grading of cFL is no longer mandatory. FL with a predominantly diffuse growth pattern had been previously recognized in WHO-HAEM4R. It frequently occurs as a large tumor in the inguinal region and is associated with CD23 expression. An absence of the IGH::BCL2 fusion and frequent STAT6 mutations along with 1p36 deletion or TNFRSF14 mutation is typical. The newly introduced subtype of uFL includes two subsets that significantly diverge from cFL: one with "blastoid" and one with "large centrocyte" variant cytological features. uFL more frequently displays variant immunophenotypic and genotypic features. FLBCL is largely identical to WHO-HAEM4R FL grade 3B and renaming was done for reasons of consistency throughout the classification. In-situ follicular B-cell neoplasm, pediatric-type FL, duodenal-type FL and primary cutaneous follicle center lymphoma are categorized as discrete entities. In addition, novel findings concerning underlying biological mechanisms in the pathogenesis of early and systemic follicular lymphoma will be presented.

Predictive factors for the progression of primary localized stage small-bowel follicular lymphoma

BACKGROUND

Primary small-bowel follicular lymphoma (FL) is mainly diagnosed as a duodenal lesion during esophagogastroduodenoscopy. Recently, with the widespread use of small-bowel endoscopy, FL in the jejunum and ileum has been detected. Most patients with small-bowel FL are diagnosed at the localized stage, and a watch-and-wait policy is used. However, the predictive factors for the progression of small-bowel FL have not been clarified. This study retrospectively examined the predictive factors for the progression of primary localized stage small-bowel FL based on clinicopathological and endoscopic findings.

METHODS

We enrolled 60 consecutive patients with primary small-bowel FL diagnosed at two tertiary hospitals between January 2005 and December 2020, with localized stage, low grade, and low tumor burden with the watch-and-wait policy. We examined the predictive factors for progression according to the clinicopathological and endoscopic findings. Endoscopic findings were focused on the color tone, circumferential location of follicular lesions (circumference ≥ 1/2 or < 1/2), fusion of follicular lesions (fusion [ +] or [ -]), and protruded lesions (≥ 6 mm or < 6 mm).

RESULTS

Progressive disease was observed in 12 (20%) patients (mean observation period, 76.4 ± 55.4 months). In the multivariate analysis, "circumference ≥ 1/2" and "fusion (+)" were significant predictive factors for progression. According to the Kaplan-Meier analysis, progression-free survival was significantly shorter in the "circumference ≥ 1/2" and/or "fusion (+)" group than in the "circumference < 1/2" and "fusion ( -)" group.

CONCLUSIONS

Endoscopic findings of "circumference ≥ 1/2" and "fusion (+)" were significant predictive factors for the progression of primary localized stage small-bowel FL.

Duodenal-type follicular lymphoma more than 10 years after treatment intervention: A retrospective single-center analysis

BACKGROUND

Duodenal-type follicular lymphoma (D-FL) has been recognized as a rare entity that accounts for approximately 4% of primary gastrointestinal lymphomas. D-FL follows an indolent clinical course compared with common nodal FL and is generally considered to have a better prognosis. Therefore, the “watch and wait” approach is frequently adopted as the treatment method. Alternatively, there is an option to actively intervene in D-FL. However, the long-term outcomes of such cases are poorly understood.

AIM

To clarify the clinical outcomes after long-term follow-up in cases of D-FL with treatment intervention.

METHODS

We retrospectively analyzed patients who met the following criteria: the lesion was confirmed by endoscopy, the diagnosis of D-FL was confirmed histopathologically, and the patient was followed-up for more than 10 years after the intervention at our center.

RESULTS

We identified 5 cases of D-FL. Two patients showed a small amount of bone marrow involvement (Stage IV). Rituximab was used as a treatment for remission in all 5 patients. It was also used in combination with chemotherapy in 2 Stage IV patients as well as for maintenance treatment. Radiation therapy was performed in 2 cases, which was followed by complete remission (CR). Eventually, all 5 patients achieved CR and survived for more than 10 years. However, 3 patients experienced recurrence. One patient achieved a second CR by retreatment, and in another case, the lesion showed spontaneous disappearance. The remaining patient had systemic widespread recurrence 13 years after the first CR. Biopsy results suggested that the FL lesions were transformed into diffuse large B-cell lymphoma. The patient died 4 years later despite receiving various chemotherapies.

CONCLUSION

In this study, the treatment for patients of D-FL in Stage IV was successful. In the future, criteria for how to treat “advanced” D-FL should be established based on additional cases. This study of patients with D-FL indicates that whole-body follow-up examinations should continue for a long time due to a fatal recurrence 13 years after reaching CR.

Protein-losing Enteropathy Complicated with Primary Intestinal Follicular Lymphoma

Protein-losing enteropathy (PLE) is a rare syndrome characterized by hypoproteinemia due to gastrointestinal (GI) protein loss. Primary intestinal follicular lymphoma (PIFL), a specific variant of follicular lymphoma with essential only GI involvement, has not been reported as an etiology of PLE. We herein report a case of PLE complicated with PIFL that was successfully treated with rituximab, resulting in rapid improvement of PLE and a complete response of PIFL. Macroscopic findings of ulcerative lesions with diffuse involvement, which were precisely described by capsule and double-balloon enteroscopy at the diagnosis, also improved following the treatment. This case provides a clue suggesting factors that promote PLE in PIFL.

Synchronous colon cancer after treatment for rectal follicular lymphoma: A case report

Colorectal follicular lymphoma (FL) is rare. In addition, it is even rarer that colon cancer develops synchronously with colorectal lymphoma. The present study reports a case of sigmoid colon cancer that developed 6 months after endoscopic resection of rectal FL. A 71-year-old man with a history of developing mucosa-associated lymphoid tissue lymphoma in his stomach at age 48, right neck region at age 59 (the latter later modified as FL) and lung adenocarcinoma at age 60 now suffers from rectal FL. Endoscopic submucosal dissection (ESD) was performed at our hospital (Aiiku Hospital), and 6 months after the treatment, sigmoid colon cancer was confirmed by colonoscopy for the follow-up study. The patient was successfully curatively resected by ESD plus local resection and has survived without a recurrence for >3 years with no treatment. It was speculated that in the present case, cancer-related genes were changed as a carcinogenic mechanism due to decreased immune function associated with the onset of lymphoma.

Unusual presentation of extra-nodal double-hit follicular lymphoma: a case report

Background

To the best of our knowledge, this case represents the first report of an extranodal double-hit follicular lymphoma (DH-FL) as an intestinal polypoid lesion.

Case presentation

A 72-year-old woman presents with constipation. Colonoscopy reveals a sessile polypoid lesion of the colon bearing morphological, immunohistochemical and molecular hallmarks of DH-FL. Complete clinical staging and bone marrow biopsy showed no signs of disseminated disease. The patient, after two years of follow-up is still free of disease confirming the indolent behaviour of this limited lesion.

Conclusions

A synoptic view at all the features of the patient and not merely at the molecular hallmarks of a disease are essential to establish the correct clinical approach.

Clinical features and outcomes of duodenal-type follicular lymphoma: A single-center retrospective study

Duodenal-type follicular lymphoma (FL) is a rare and newly recognized disease. Few data are available on the outcomes and treatment strategies for patients with duodenal-type FL. We aimed to investigate the clinical features and outcomes of duodenal-type FL. We defined duodenal-type FL as involvement of the duodenum, without nodal or extranodal lesions other than intestinal lesions, pathologically diagnosed as FL. We reviewed 26 patients with duodenal-type FL between January 2011 and December 2020 at Kobe City Hospital Organization, Kobe City Medical Center General Hospital. In particular, patients were selected for the watch and wait (WW) strategy and followed up with regular esophagogastroduodenoscopy about once a year at our institution. The patient characteristics were as follows: median age 63.5 years (range: 42-78), sex (male, 15; female, 11), stage (I, 26), and grade (I, 26). Regarding treatment strategies, 23 patients were selected for the WW strategy, and three patients received initial rituximab therapy. The median follow-up period was 65.5 months (range: 0.2-109). Five-year progression-free survival and 5-year overall survival rates were 86.3% and 100%, respectively. Among the 23 patients selected for the WW strategy, six had spontaneous complete regression, and 14 had stable disease, and three had progressive disease, including one with histologic transformation. The WW strategy for patients with duodenal-type FL could be an appropriate and safe treatment option. However, in several cases, disease progression was documented, and regular follow-up is important.

Duodenal Follicular Lymphoma: Track or Treat?

Duodenal follicular lymphoma (DFL) is a rare variety of non-Hodgkin's lymphoma of the gastrointestinal tract that usually carries a favorable course, recognized as a new entity in 2016. It is usually diagnosed at an early stage located predominantly in the second portion of the duodenum. We report the case of a 74-year-old male patient with epigastric pain in whom gastroscopy revealed white mucosal nodules that were pathologically diagnosed as grade 1-2 DFL. Staging investigations revealed secondary lesions in the spleen and at the base of the tongue together with latero-cervical adenopathy. The tumor was stage IV according to the Lugano staging system. We reviewed the recent (last five years) literature defining the importance of combination therapy in the advanced stage. The patient achieved complete remission of the disease through chemoimmunotherapy following the Rituximab-Bendamustine scheme.

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)

Background/Aims

Methods

Results

Conclusions

A rare case of duodenal-type follicular lymphoma in rectum appearing as hyperplastic polyp with metachronous appearance in duodenum and stomach

Hyperplastic polyps consist a very frequent finding in colonoscopy having a very low potential to malignancy. According to the international guidelines, it is recommended that all polyps should be resected except for diminutive (≤ 5 mm) rectal and rectosigmoid polyps which are predicted with confidence to be hyperplastic. Therefore, in departments where optical diagnosis can be ensured, a "resect and discard" strategy may be implemented for diminutive polyps. In our case, a duodenal-type follicular lymphoma was detected in a 5 mm rectum polyp with hyperplastic appearance. After 4 months, the lymphoma was detected also in stomach and duodenum. Under therapy with Rituximab, she is in remission. To our knowledge, there has never been reported such a case in the literature. Furthermore, it alerts us that we should be very cautious with the optical diagnosis and the "resect and discard strategy".

Need to Inspect the Total Gastrointestinal Tract of Patients With Malignant Lymphomas

BACKGROUND/AIM

Malignant lymphoma (ML) cases with overlapping gastrointestinal (GI) lesions are often encountered. We aimed to elucidate the importance of examining the GI tract in patients with ML and assess the overlap rate.

PATIENTS AND METHODS

We analysed 190 patients diagnosed with GI MLs. We compared the overlap rates among the different histopathological types.

RESULTS

Twenty-five (13.2%) patients had overlapping GI lesions in more than two segments. The overlap rates were 100% in mantle cell lymphomas (MCL), 27.6% in follicular lymphomas (FL), and 16.3% in diffuse large B-cell lymphomas (DLBCL). MCL, FL, and DLBCL cases showed significantly higher overlap rates than mucosa-associated lymphoid tissue lymphoma cases (p<0.01). About 64.0% of cases of ML with overlapping lesions involved the small intestine.

CONCLUSION

In GI ML cases, it is ideal to examine the entire GI tract by esophagogastroduodenoscopy, colonoscopy, and capsule endoscopy and/or balloon-assisted endoscopy, especially in MCL, FL, and DLBCL.

Squamous Metaplasia of the Stomach Associated with Lymphoma Infiltration

We herein report a patient who presented with follicular lymphoma. Although the stomach was initially intact, mucosal redness and multiple erosions appeared in the gastric body owing to infiltration of the follicular lymphoma cells. Subsequently, a slightly depressed, white area lacking gastric mucosal structure was detected in the lesser curvature of the gastric cardia and body, where lymphoma cell infiltration was also pathologically observed beneath the stratified squamous epithelium. This case indicated that, although infrequent, prolonged mucosal injury owing to lymphoma infiltration can cause squamous metaplasia in the stomach.

Ibritumomab Tiuxetan Radioimmunotherapy for Primary Gastrointestinal Follicular Lymphoma

Primary gastrointestinal follicular lymphoma (PGIFL) is characterized by localized involvement of the gastrointestinal (GI) tract. PGIFL usually runs an indolent course. External beam radiation therapy is curative in a substantial proportion of localized follicular lymphomas, but GI toxicities may discourage its use in PGIFL. Ibritumomab tiuxetan radioimmunotherapy (RIT) is a radioimmunoconjugate of anti-CD20 monoclonal antibody linked to chelator tiuxetan and radioisotope. RIT delivers confined high-intensity radiation with short path length specifically targeting lymphoma cells and sparing normal tissue. In this case series report, we included six cases of PGIFL treated with RIT. All patients had low-risk, localized, and nonbulky disease. All patients responded completely and were relapse-free for the duration of follow-up. Hematologic toxicities were seen, but none were serious. RIT is a potentially curative treatment option in PGIFL with a tolerable toxicity profile.

Primary follicular lymphoma of colon: A case series and review of literature

Follicular lymphoma of the colon is rare, accounting for 1% to 2% of cases in the gastrointestinal tract. Despite the absence of randomized clinical trials, NCCN stage III and IV colonic follicular lymphomas are routinely treated with chemotherapy with good clinical response. We present 2 cases of advanced stage follicular lymphoma of colon that were effectively treated with bendamustine-based chemotherapy regimens.

Gastrointestinal Tract Lymphomas: A Review of the Most Commonly Encountered Lymphomas

CONTEXT.—

The gastrointestinal (GI) tract is the most common site of extranodal non-Hodgkin lymphoma, accounting for 20% to 40% of all extranodal lymphomas. The majority of these are systemic processes secondarily involving the GI tract. Primary GI lymphomas are less common, accounting for approximately 10% to 15% of all non-Hodgkin lymphoma. Most non-Hodgkin lymphoma involving the GI tract are of B-cell lineage, of which diffuse large B-cell lymphoma is the most common subtype, irrespective of location.

OBJECTIVE.—

To review the lymphoproliferative neoplasms of B-cell and T-cell lineage involving the luminal GI tract according to the most prevalent subtypes at each anatomic site.

DATA SOURCE.—

Systematic search of the PubMed database for updated literature on GI lymphomas epidemiology, subtypes, clinical, endoscopic, and genetic findings. Histologic images are derived from our collection of clinical cases.

CONCLUSIONS.—

The GI tract is the most common site of extranodal lymphoproliferative neoplasms. Recognition of the most frequently encountered GI lymphomas is imperative for patient management and treatment.

Tiny but Mighty: Collision Tumor of a Superficial Adenocarcinoma Arising From a Tubulovillous Adenoma with Associated Low-Grade Follicular Lymphoma

Collision tumors are rare and there have only been a few previously described cases between an intestinal adenoma and a lymphoma. We report the first case of a 74-year-old woman who on investigation for iron deficiency had a tubulovillous adenoma with underlying follicular lymphoma. The atypical lymphoid proliferation showed immunohistochemical positivity for cluster of differentiation 20 (CD20), B-cell lymphoma 2 (BCL2), and B-cell lymphoma 6 (BCL6). Subsequent right hemicolectomy showed a superficially invasive adenocarcinoma.

Common Presentation of an Uncommon Small Intestinal Lymphoma: A Rare Case Entity

Primary gastrointestinal NHL accounts for 30-40% of all extranodal NHL. Primary gastrointestinal lymphomas constitute 5% of total gut neoplasms. Bowel perforation is a severe life-threatening complication and sometimes initial presentation of gastrointestinal lymphoma. A 60-year-old man presented with complaints of abdominal pain, distension, nausea and vomiting. There was clinical suspicion of acute intestinal perforation, which was confirmed by radiology. The patient underwent emergency laparotomy. The resected bowel on histopathological examination and immunohistochemistry was diagnosed as the high-grade transformation of follicular lymphoma (FL). The patient received 6 cycles of chemotherapy and is doing well at 3 years of follow-up. Herein, we report this rare malignancy of the small intestine. FL mostly presents as a nodal disease but also involves the extranodal sites. The most common site of primary gastrointestinal-follicular lymphoma (GI-FL) is the small intestine. The cellular and molecular characteristic of GI-FL is different from that of the nodal FL. Extranodal FL is usually localized, but the prognosis of transformed FL is low, and these are managed by surgery followed by chemotherapy. High clinical suspicion and extensive sampling of perforated bowel are essential to diagnose the high-grade transformation of FL.

Recent advances upper gastrointestinal lymphomas: molecular updates and diagnostic implications

Approximately one-third of extranodal non-Hodgkin lymphomas involve the gastrointestinal (GI) tract, with the vast majority being diagnosed in the stomach, duodenum, or proximal small intestine. A few entities, especially diffuse large B-cell lymphoma and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue, represent the majority of cases. In addition, there are diseases specific to or characteristic of the GI tract, and any type of systemic lymphoma can present in or disseminate to these organs. The recent advances in the genetic and molecular characterisation of lymphoid neoplasms have translated into notable changes in the classification of primary GI T-cell neoplasms and the recommended diagnostic approach to aggressive B-cell tumours. In many instances, diagnoses rely on morphology and immunophenotype, but there is an increasing need to incorporate molecular genetic markers. Moreover, it is also important to take into consideration the endoscopic and clinical presentations. This review gives an update on the most recent developments in the pathology and molecular pathology of upper GI lymphoproliferative diseases.

Clinical characteristics of adult T-cell leukemia/lymphoma infiltration in the gastrointestinal tract

Background

Adult T-cell leukemia/lymphoma (ATLL) is a peripheral T-cell malignancy caused by human T-cell leukemia virus type 1. The clinical course of ATLL is very heterogeneous, and many organs, including the gastrointestinal (GI) tract, can be involved. However, there are few detailed reports on ATLL infiltration in the GI tract. We investigated the clinical characteristics of ATLL infiltration in the GI tract.

Methods

This retrospective observational single-center study included 40 consecutive ATLL patients who underwent GI endoscopy. The patients’ demographic and clinical characteristics and endoscopic findings were analyzed retrospectively. Patients with ATLL who were diagnosed by histological examination were divided into two groups based on GI tract infiltration.

Results

Multivariate analysis revealed that the absence of skin lesions was significantly associated with GI infiltration (P < 0.05). Furthermore, the infiltration group tended to have similar macroscopic lesions in the upper and lower GI tracts, such as diffuse type, tumor-forming type, and giant-fold type.

Conclusions

GI endoscopy may be considered for ATLL patients without skin lesions.

Density and size of lymphoid follicles are useful clues in differentiating primary intestinal follicular lymphoma from intestinal reactive lymphoid hyperplasia

Background

Primary intestinal follicular lymphoma (PI-FL) is a rare and indolent lymphoma and is challenging for diagnosis with endoscopic biopsy specimens. Whole slide imaging (WSI) has been increasingly used for assisting pathologic diagnosis, but not for lymphoma yet, probably because there are usually too many immunostained sections in a single case. In this study we attempted to identify morphological clues of PI-FL in the endoscopic biopsy specimens by measuring various parameters using WSI.

Methods

We retrospectively investigated 21 PI-FL cases, and scanned the HE sections from 17 of these cases with endoscopic biopsy specimens. Sections from 17 intestinal biopsies showing reactive lymphoid hyperplasia were scanned for comparison. The density and diameter of lymphoid follicles and the shortest distance of these follicles to the surface epithelia were measured on WSI. Comparisons of the aforementioned parameters were made between the neoplastic and reactive follicles.

Results

The density of follicles was significantly higher in PI-FL than that of reactive hyperplasia (median 0.5 vs. 0.2/mm²; p < 0.01). Furthermore, the neoplastic follicles were significantly larger (median diameter 756.9 vs. 479.7 μm; p < 0.01). The shortest distance of follicles to the surface epithelia tended to be closer in PI-FL (104.7 vs. 177.8 μm, p = 0.056), but not statistically significant.

Conclusions

In this study we found that in PI-FL the density and diameter of lymphoid follicles as measured from WSI were significantly different from that of intestinal reactive lymphoid hyperplasia. When facing the diagnostic challenge between these two entities in routine practice, pathologists might be alerted by these morphological clues and request for immunohistochemistry for differential diagnosis.

Primary Colorectal Follicular Lymphoma Observed by Magnifying Endoscopy, with a Five-year Follow-up

Colorectal involvement is very rare in cases of follicular lymphoma. Colonoscopy of a 69-year-old man revealed an aggregation of multiple whitish nodules in the sigmoid colon. Magnifying endoscopy with narrow-band imaging demonstrated a coiled and elongated microvascular pattern on the surface and crystal violet staining showed a type I pit pattern. A biopsy showed follicular lymphoma (Grade 1), and no other involvement of lymphoma was detected. Following a diagnosis of primary colorectal follicular lymphoma stage I (Lugano classification), the patient was monitored by watch-and-wait therapy. We documented the endoscopic images of colorectal follicular lymphoma in the present case.

What do we know about duodenal-type follicular lymphoma? From pathological definition to treatment options

Duodenal-type follicular lymphoma (DFL) is a newly recognised variant of follicular lymphoma (FL), although little is known about its biology and clinical evolution. In general, patients tend to have mild symptoms and do not require therapy, comparable with other forms of low-tumour burden asymptomatic FL. Specific pathological features, such as a dendritic cell meshwork, low expression of CD10 and upregulation of activation-induced cytidine deaminase can help the diagnosis. The molecular landscape of DFL is similar to the classical nodal presentation of FL, although studies using gene expression profiling demonstrate a close relation with MALT lymphomas. Markers associated with inflammation have suggested that the microenvironment plays a likely role in the pathogenesis of DFL and its low progression rate. Clinical series published vary between 20-63 patients with an estimated overall survival between 92-100% and a median follow-up ranging between 20 and 107 months. Treatment options include a watch and wait strategy, rituximab monotherapy and radiotherapy. In this review, we summarise current pathological data and treatment studies in DFL.

Update on lymphoproliferative disorders of the gastrointestinal tract: disease spectrum from indolent lymphoproliferations to aggressive lymphomas

This paper summarizes two sessions of the workshop during the XIX meeting of the European Association for Haematopathology (EAHP) held in Edinburgh in September 2018 dedicated to lymphomas of the gastrointestinal tract. The first session focused on the clinical and pathological features of primary gastrointestinal T cell and NK-cell lymphoproliferative disorders. The distinction between precursor lesions (RCD type 2) and enteropathy-associated T cell lymphoma were stressed, including the discussion of new diagnostic markers for the identification of aberrant phenotypes. Indolent T cell lymphoproliferative disorders of the gastrointestinal tract cases showed phenotypic heterogeneity with novel molecular alterations in few cases, such as STAT3-JAK2 fusion. In addition, novel clonal markers of disease, such as AXL and JAK3 somatic variants support the neoplastic nature of NK-cell enteropathy. The session on gastrointestinal tract B cell lymphoproliferations was dedicated to B cell lymphoproliferative disorders that arise primarily in the gastrointestinal tract (i.e., duodenal-type follicular lymphoma) or preferentially involve the digestive tract, such as large B cell lymphoma with IRF4 translocation and mantle cell lymphoma (MCL), including diverse molecular subtypes (i.e., CCND3-positive MCL mimicking MALT lymphoma). Challenging cases of high-grade B cell lymphomas with complex genetic profiles demonstrated the usefulness of novel molecular diagnostic methods such as targeted NGS to identify high-risk genetic features with potential clinical impact.

Primary non-ampullary duodenal follicular lymphoma presenting with obstructive jaundice

Primary gastrointestinal follicular lymphoma is a rare disease. Follicular lymphoma does not cause any typical symptoms, although it usually shows the presence of multiple white granules on endoscopy. Few patients with follicular lymphoma present with the initial symptom of jaundice, which is usually associated with follicular lymphomas located in the papilla of Vater. Herein, we present the first case of a duodenal follicular lymphoma that presented with obstructive jaundice despite not being located in the ampulla, and it did not demonstrate the typical endoscopic findings of multiple white granules. A 72-year-old Japanese man with jaundice was referred to our hospital. Imaging revealed a hypovascular lesion extending into the second part of the duodenum and the pancreatic head, and the common bile duct was dilated upstream of the lesion. Biopsy of the lesion was negative for malignancy. Finally, we suspected the lesion as a pancreatic adenosquamous carcinoma, and not a typical pancreatic ductal carcinoma, because the lesion showed no pancreatic duct dilation and had a partially hyperechoic part within. Therefore, we performed pancreaticoduodenectomy. The final diagnosis was a duodenal follicular lymphoma. The findings of this case may assist in distinguishing between atypical follicular lymphoma and jaundice from pancreatic cancer.

Usefulness of magnifying endoscopy and endoscopic ultrasonography for the gastric involvement of follicular lymphoma

A 61-year-old man received an esophagogastroduodenoscopy for further investigation of mesenteric lymphadenopathy. Esophagogastroduodenoscopy revealed swollen gastric folds and cobble stone mucosa in the gastric body. Magnifying endoscopy with narrow-band imaging showed branched abnormal vessels and the absence or destruction of gastric pits. Endoscopic ultrasonography (EUS) depicted homogeneously hypoechoic thickening of the submucosal layer where the mucosal changes were observed. The patient was diagnosed with follicular lymphoma by biopsy of these lesions. We should recognize that these endoscopic features are consistent with follicular lymphoma involving the stomach and that concurrent EUS is useful for diagnosis and identification of adequate biopsy sites.

Clinicopathological characteristics of diffuse large B-cell lymphoma involving small and large intestines: an analysis of 126 patients

We analyzed the clinicopathologic characteristics of 136 intestinal diffuse large B-cell lymphomas (DLBCLs) among 126 patients. The DLBCL sites were categorized as: duodenum (n = 23), ileocecal region (n = 63), other small intestine (n = 29), rectum (n = 7), and other large intestine (n = 14). Patients with DLBCLs of the ileocecal region or other small intestine frequently underwent surgery for ileus or perforations (P < 0.001), were predominantly male (P = 0.042), and had a higher incidence of limited-stage disease (P = 0.001), lower International Prognostic Index (P = 0.015), and lower incidence of lactate dehydrogenase elevation (P = 0.007) than those with DLBCLs of other regions. Half of the intestinal DLBCLs exhibited the germinal center B-cell phenotype. A low-grade B-cell lymphoma background was found in 21% of the cases; the prevalence was significantly lower in the ileocecal region (13%, P = 0.025), suggesting a higher incidence of de novo DLBCLs. Intestinal follicular lymphoma (FL) and mucosa-associated lymphoid tissue (MALT) lymphoma backgrounds were observed in 10% and 0% of the cases, respectively. Five percent (5/107) of intestinal DLBCL cases were Epstein-Barr virus-encoded RNA-1 positive. The clinicopathologic characteristics of the DLBCLs differed by region. Histologic transformation of intestinal FL was observed in around 10% of the intestinal DLBCL cases.

Histological transformation in duodenal-type follicular lymphoma: a case report and review of the literature

Duodenal-type follicular lymphoma (DFL) is a rare variant of follicular lymphoma (FL) characterized by distinctive clinical features such as localization and favorable prognosis. We herein report a case of DFL in which histological transformation into diffuse large B-cell lymphoma developed 7 years after diagnosis. The transformed lymphoma was refractory to chemotherapy, and the patient passed away due to disease progression. To date, there have been only a limited number of reported cases of histological transformation of DFL, and the clinical outcomes of those cases except our present case have been favorable, with good responses to chemotherapy. Although the histological transformation of DFL is a rare event, the clinical course of the present case suggested that it would be a fatal event and underscore the importance of the life-long management of DFL. Further accumulation of cases is required to elucidate its incidence, characteristics, and prognosis.

Development and internal validation of a risk scoring system for gastrointestinal events requiring surgery in gastrointestinal lymphoma patients

BACKGROUND AND AIM

The predictors of severe gastrointestinal (GI) events in GI lymphoma patients are unclear. We aimed to develop a risk scoring system for GI events requiring surgery.

METHODS

In this retrospective study of 192 patients with GI lymphoma, the state of lymphoma, macroscopic findings, examination results, and International Prognostic Index were assessed. We developed a risk score for GI events that required surgery and assessed its accuracy by calculating the area under the receiver operating characteristic curve (AUC). Internal validation was performed using bootstrap resampling.

RESULTS

Severe GI events occurred in 21 (11%) patients. We developed a 4-point scoring system (the FLASH score) comprising the following three independent predictors (weighted by regression coefficients): (i) focal appearance and large size (≥ 40 mm), 1 point; (ii) aggressive lymphoma of the small bowel, 2 points; and (iii) high (18)F-fluorodeoxyglucose positron emission tomography uptake, 1 point. The score predicted severe GI events with an AUC value of 0.91 (internal validation; AUC, 0.86). Risk was classified into three categories: the GI event rate was 0% in the low-risk group (0 points), 9% in the intermediate-risk group (1-2 points), and 61% in the high-risk group (3-4 points) (AUC, 0.89).

CONCLUSIONS

We developed and internally validated a risk scoring system (the FLASH score) that included macroscopic findings to predict severe GI events in GI lymphoma patients. Patients with high scores are candidates for elective surgery to prevent GI events.

Duodenal-Type Follicular Lymphoma: A Clinicopathologic Review

Duodenal-type follicular lymphoma (D-FL) is a newly recognized entity in the 2016 World Health Organization classification update. It has an immunophenotype similar to that of other FLs and usually carries the typical t(14;18)(q32;q21) translocation. However, unlike other FLs, D-FL is almost always diagnosed at a low stage and stays localized to the small intestine, most commonly the second portion of the duodenum, whereas the vast majority of other FLs are diagnosed at an advanced stage. Additionally, D-FL gene expression and pathogenesis appear to be more closely related to extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue than to other types of FL. Therefore, many oncologists have opted to treat this variant of FL in a "watch and wait" manner because of its excellent prognosis and the rarity of D-FL to progress even when no treatments are attempted.

Primary Colorectal Follicular Lymphoma in 3 Dogs

Primary colorectal follicular lymphomas are rare indolent lymphoid neoplasms in humans that have not been reported in dogs. We describe 3 cases of primary colorectal follicular lymphoma in dogs with histologic and immunohistochemical features similar to their human counterpart. Initial clinical signs in all dogs included tenesmus, hematochezia, and a palpable rectal mass. Two dogs were castrated males and 1 an intact female, between 9 months and 2 years of age, and of varied breeds. All 3 cases of colorectal follicular lymphoma were characterized by proliferation of follicular germinal centers with no polarity or mantle zone and were composed of centrocytes admixed with fewer centroblasts. By immunohistochemistry, lymphoid cells expressed CD20, BCL2, and BCL6 and lacked expression of CD3, CD5, and cyclin D1. Polymerase chain reaction for rearrangements of the immunoglobulin heavy chain confirmed a monoclonal population in all cases. In 2 of the 3 cases, a solitary nodular colorectal mass was excised and appeared curative; however, the third case had multiple colorectal masses and the animal developed multicentric lymphoma. This case series immunohistochemically characterizes and distinguishes colorectal follicular lymphoma from atypical lymphoid hyperplasia.

Colorectal follicular lymphoma: A case report

RATIONALE

Considering the low incidence of colorectal follicular lymphoma (FL) and its clinical features in endoscopic views, only a few studies have described the pathological diagnosis and treatment of this disease. This study aimed to reveal the overall process of clinical diagnosis and treatment of colorectal FL by conducting a case review.

PATIENT CONCERNS

A 27-year-old female presented to our department because of "severe bloody stool" lasting for more than 1 month. Her primary symptom was melena. Colonoscopy revealed widespread flat polyps with various immunophenotypes (CD10+, BCL2+, BCL6+, cyclin D1-, CD5-) in the colorectal area.

DIAGNOSIS

In accordance with manifestations on positron emission tomography-computed tomography (PET/CT), the patient was diagnosed with stage IV colorectal FL.

INTERVENTIONS

PET/CT reexamination after 2 courses of rituximab, cyclophosphamide, liposomal doxorubicin, vincristine sulfate, and hydroprednisone (R-CHOP) regimen and 3 courses of R-CHOP plus etoposide regimen for chemotherapy indicated a significant reduction in tumor burden. Subsequently, rituximab was administered alone in 2 treatment courses.

OUTCOMES

Lesions on PET/CT disappeared after reexamination. No recurrence was observed within the 12-month follow-up period.

LESSONS

Colorectal FL is a rare disease with an inert clinical course and is common in the ileocecal area. Endoscopic views show multiple polyps. Interventional treatment is usually provided after observation of clinical symptoms or during disease progression. The disease has a relatively good prognosis.

Coexistence of primary colorectal follicular lymphoma and multiple myeloma: a case report

Colorectal follicular lymphoma (FL) occurs less frequently than duodenal-type FL, which is an established entity, and primary multiple FL only involving the colon is rare. Furthermore, the coexistence of lymphoma and multiple myeloma (MM) within the same patient is rare and the current study reports such a case. The patient was an asymptomatic 62-year-old man. He underwent colonoscopy screening, which revealed at least five polypoid tumors from the cecum to the rectum. Biopsy samples stained positive for CD20 and B-cell lymphoma 2 (BCL2) but stained negative for CD10, and fluorescence in situ hybridization analysis identified IGH/BCL2 in 95.2% of the tumor cells. Based on these findings, the patient was diagnosed with FL. On the bone marrow aspirate, the plasma cell count was 30% of all nucleated cells. Bence-Jones κ-type protein was detected by protein electrophoresis in serum and urine. The serum-free light chain κ/λ level was significantly elevated (484.3). Thus, the patient was also diagnosed with MM. Both FL and MM were targeted therapeutically; rituximab and bendamustine were effective for FL, and lenalidomide and low-dose dexamethasone were effective for MM. The patient was treated for 3 years and 7 months and, until now, was off-treatment for 4 years without rapid progression of the two malignancies. Although both diseases are still present, the patient has maintained stable disease. Our findings suggest that lymphoma and MM should be targeted separately as independent hematological malignancies when they occur concurrently.

Gastrointestinal follicular lymphoma: Current knowledge and future challenges

The gastrointestinal (GI) tract is the most commonly involved site of extranodal follicular lymphoma (FL). GI-FL shows very indolent clinical behavior and localized at GI tract without any progression or transformation compared to nodal FL. The most frequently involved site of the GI tract was the duodenum followed by the jejunum and ileum, and only 15% of FL arising in the second part of the duodenum were localized there without scattered very small daughter lesions in other GI tract examined by double-balloon endoscopy. The typical macroscopic appearance of GI-FL was multiple white nodules. Microscopically, neoplastic cells were small- to medium-sized lymphoid cells and formed neoplastic follicles. Most of the cases (>95%) were histologically Grade 1 to 2 (low grade). Several pathological and molecular characteristics were seen in GI-FL (especially duodenal FL) compared with nodal FL: immunoglobulin heavy chain deviation to VH4 and VH5; memory B-cell immunophenotype; and molecular features shared by mucosa-associated lymphoid tissue lymphoma. Considering the pathological and molecular uniqueness of this disease, GI-FL should be separately managed from nodal FL.