A clinicopathologic study of gastric mucosa-associated lymphoid tissue lymphoma

Repurposing Drugs in Oncology (ReDO)-clarithromycin as an anti-cancer agent

Clarithromycin (CAM) is a well-known macrolide antibiotic available as a generic drug. CAM is traditionally used for many types of bacterial infections, treatment of Lyme disease and eradication of gastric infection with Helicobacter pylori. Extensive preclinical and clinical data demonstrate a potential role for CAM to treat various tumours in combination with conventional treatment. The mechanisms of action underlying the anti-tumour activity of CAM are multiple and include prolonged reduction of pro-inflammatory cytokines, autophagy inhibition, and anti-angiogenesis. Here, we present an overview of the current preclinical (in vitro and in vivo) and clinical evidence supporting the role of CAM in cancer. Overall these findings justify further research with CAM in many tumour types, with multiple myeloma, lymphoma, chronic myeloid leukaemia (CML), and lung cancer having the highest level of evidence. Finally, a series of proposals are being made to further investigate the use of CAM in clinical trials which offer the greatest prospect of clinical benefit to patients.

Predictive value of endoscopy and endoscopic ultrasonography for regression of gastric diffuse large B-cell lymphomas after Helicobacter pylori eradication

BACKGROUND

Some gastric diffuse large B-cell lymphomas have been reported to regress completely after the successful eradication of Helicobacter pylori. The aim of this study was to investigate the clinical characteristics of gastric diffuse large B-cell lymphomas without any detectable mucosa-associated lymphoid tissue (MALT) lymphoma that went into complete remission after successful H. pylori eradication.

PATIENTS AND METHODS

We examined the effect of H. pylori eradication in 15 H. pylori-positive gastric diffuse large B-cell lymphoma patients without any evidence of an associated MALT lymphoma (clinical stage I by the Lugano classification) by endoscopic examination including biopsies, endoscopic ultrasonography, computed tomography, and bone marrow aspiration.

RESULTS

H. pylori eradication was successful in all the patients and complete remission was achieved in four patients whose clinical stage was I. By endoscopic examination, these gastric lesions appeared to be superficial. The depth by endoscopic ultrasonography was restricted to the mucosa in two patients and to the shallow portion of the submucosa in the other two patients. All four patients remained in complete remission for 7-100 months.

CONCLUSION

In gastric diffuse large B-cell lymphomas without a concomitant MALT lymphoma but associated with H. pylori infection, only superficial cases and lesions limited to the shallow portion of the submucosa regressed completely after successful H. pylori eradication. The endoscopic appearance and the rating of the depth of invasion by endosonography are both valuable for predicting the efficacy of H. pylori eradication in treating gastric diffuse large B-cell lymphomas.

Therapy of gastric mucosa associated lymphoid tissue lymphoma

Gastric mucosa associated lymphoid tissue (MALT) lymphoma has recently been incorporated into the World Health Organization (WHO) lymphoma classification, termed as extranodal marginal zone B-cell lymphoma of MALT-type. In about 90% of cases this lymphoma is associated with H pylori infection which has been clearly shown to play a causative role in lymphomagenesis. Although much knowledge has been gained in defining the clinical features, natural history, pathology, and molecular genetics of the disease in the last decade, the optimal treatment approach for gastric MALT lymphomas, especially locally advanced cases, is still evolving. In this review we focus on data for the therapeutic, stage dependent management of gastric MALT lymphoma. Hence, the role of eradication therapy, surgery, chemotherapy and radiotherapy is critically analyzed. Based on these data, we suggest a therapeutic algorithm that might help to better stratify patients for optimal treatment success.

The value of EUS in predicting the response of gastric mucosa-associated lymphoid tissue lymphoma to Helicobacter pylori eradication

BACKGROUND

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is associated with Helicobacter pylori infection, and regression of the tumor has been described after its eradication.

OBJECTIVE

To determine the value of EUS, in addition to other clinical/endoscopic features, in predicting the response of low-grade MALT lymphoma to H pylori eradication.

DESIGN

A retrospective, single-center study.

SETTING AND PATIENTS

Twenty-two patients with primary gastric MALT lymphoma were identified through a retrospective review of charts of patients seen at the American University of Beirut Medical Center. Only 19 patients with histopathologically confirmed gastric MALT lymphoma and H pylori infection who had EUS staging were included in the study.

MAIN OUTCOME MEASUREMENTS

Regression of the gastric MALT lymphoma as determined by follow-up endoscopy and mucosal biopsies.

RESULTS

Patients with disease restricted to the gastric mucosa had a significantly higher rate of complete remission after H pylori eradication compared with patients who had disease infiltrating into the gastric submucosa (77.8% vs 12.5%, P value .007). There was no statistical difference in terms of the mean follow-up time to achieve such response (P value .212). Age, sex, location of the tumor within the stomach, and endoscopic appearance did not correlate with the probability of complete remission of the MALT lymphoma.

LIMITATIONS

The limitations include a retrospective design and a relatively small sample population.

CONCLUSION

EUS determination of the invasion depth of gastric MALT lymphoma helps predict a complete response to H pylori eradication.

p27kip1 expression is inversely related to the grade of gastric MALT lymphoma

BACKGROUND

Decreased or lost expression of the cyclin-dependent kinase inhibitor p27kip1 protein has been found to be a poor prognostic factor in many cancers, including gastric cancer.

AIM

To evaluate p27kip1 expression in gastric mucosa-associated lymphoid tissue (MALT) and gastric B-cell lymphoma.

METHODS

Fifty-two cases of gastric lymphoma, mean age 68.7 yr (range 23-90 yr), 11 of chronic Helicobacter pylori-associated gastritis, and 5 of normal gastric mucosa were studied. Patients were classified into two groups. Stage IE gastric lymphomas were defined as local gastric lymphoma of MALT and more advanced stages as advanced gastric lymphoma. Twenty-three patients diagnosed as stage IE, 13 of these were low-grade and 10 diffuse large B-cell lymphoma (DLBL). Twenty-nine patients were at stage IIE or above, 18 with low-grade and 11 with DLBL. Serial sections were evaluated by immunohistochemistry after staining with antibodies against p27/Kip1 and Ki-67.

RESULTS

The proliferative index was higher in gastric DLBL than in low-grade MALT lymphomas, 57.1+/-31.2 vs 17.3+/-20.6 (p=0.0001). The mean p27kip1 expression score for high-grade patients was significantly lower compared with that of low-grade patients, 0.5+/-0.4 and 1.6+/-0.8, respectively (p=0.001). Comparative evaluation of p27kip1 expression in malignant lymphoid cells revealed that B cells of the localized gastric DLBL patients expressed the least p27kip1, 0.36+/-0.32. This value was lower than that of malignant lymphoid cells of patients with advanced DLBL, 0.64+/-0.53, advanced low-grade MALT lymphoma, 1.59+/-0.79, and localized low-grade MALT lymphoma, 1.59+/-0.84. In the multivariate model in which all p27kip1 variables were entered, the expression of p27kip1 in malignant lymphoid cells was inversely correlated with the grade of the lymphoma irrespective of the stage of the disease (p=0.0001), and significantly predicted grade: OR:0.07, 95% CI 0.07-0.31, p=0.0001.

CONCLUSION

p27kip1 may be a putative distinct molecular marker to differentiate between low-grade and high-grade gastric lymphoma.

Gastric lymphoma: the revolution of the past decade

BACKGROUND

Gastric MALT type lymphomas are distinct lymphomas that may develop after chronic antigenic stimulation caused by infection with Helicobacter pylori. An early antigen-dependent phase precedes the development of an antigen-independent phase.

METHODS

Narrative review.

RESULTS

The causative relationship between a chronic H. pylori infection and gastric MALT lymphomas has been based on epidemiological, histological, experimental and therapeutic studies. H. pylori eradication leads to a histological remission in +/- 70% of patients in early stage low-grade MALT lymphoma. There is no basis for therapeutic consequences in the case of persistent monoclonality. Full thickness invasion of the gastric wall and lymph node involvement and/or high-grade lymphoma denote the transition to an antigen-independent phase and calls for conventional treatment modalities. Molecular findings show a specific translocation in low-grade MALT lymphomas: t(11,18) and nuclear expression of bcl-10 that are highly indicative of the transition of the antigen-dependent into the antigen-independent phase. Other chromosomal and molecular findings are probably also involved.

CONCLUSION

The multistep pathogenesis of chronic H. pylori gastritis into low-grade gastric MALT lymphoma and tumour progression to a higher stage and grade are characterized by multiple molecular biological events. Antigen-dependency during the early phase of this malignancy is proven by the results of H. pylori eradication.

Radiographic findings of primary B-cell lymphoma of the stomach: low-grade versus high-grade malignancy in relation to the mucosa-associated lymphoid tissue concept

OBJECTIVE

We undertook this study to assess how well double-contrast radiography and CT allow radiologists to differentiate low-grade from high-grade mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach.

MATERIALS AND METHODS

We retrospectively reviewed the upper gastrointestinal radiographs and contrast-enhanced CT scans of 57 patients with pathologically proven primary gastric lymphoma (low-grade [n = 29] and high-grade [n = 28] MALT lymphoma).

RESULTS

On upper gastrointestinal radiography, ulceration (39%) was the most common finding in low-grade lymphoma, whereas polypoid appearance (38%) was the most common in high-grade lymphoma. In the 29 patients (33 lesions) with low-grade MALT lymphoma, upper gastrointestinal radiography revealed 13 ulcerative lesions (39%), 10 nodular lesions (30%), four infiltrative lesions (12%), two polypoid lesions (6%), and four combined lesions (12%). In the 28 patients (29 lesions) with high-grade lymphoma, upper gastrointestinal radiography revealed 11 polypoid lesions (38%), nine infiltrative lesions (31%), six ulcerative lesions (20%), one nodular lesion (3%), and two combined lesions (7%). On CT, thickening of the gastric wall in low-grade lymphoma (range, 0.3-2.5 cm; mean, 0.8 cm) was much less than that in high-grade lymphoma (range, 0.7-8.0 cm; mean, 2.5 cm). Abdominal lymphadenopathy was less frequent in low-grade lymphoma (14%) than in high-grade lymphoma (75%).

CONCLUSION

Most low-grade lymphomas show superficial spreading lesions, such as mucosal nodularity, shallow ulcer, and minimal fold thickening, on upper gastrointestinal radiography, whereas most high-grade lymphomas show mass-forming lesions or severe fold thickening.

The importance of endoscopic ultrasonography in the management of low-grade gastric mucosa-associated lymphoid tissue lymphoma

BACKGROUND

Anti-Helicobacter pylori therapy has been reported to cause regression of low-grade gastric mucosa-associated lymphoid tissue lymphoma in a high percentage of patients. However, in some patients, these lesions persist despite antibiotic treatment.

AIM

To determine the various endosonographic findings that may predict the regression of low-grade gastric mucosa-associated lymphoid tissue lymphoma post-antibiotics.

METHODS

Seventy-six patients with Helicobacter pylori-positive gastric mucosa-associated lymphoid tissue lymphoma were studied. Follow-up data were available on 51 patients. All patients were treated with antibiotics. Participants underwent pre- and post-anti-Helicobacter pylori therapy endoscopy with gastric biopsies, followed by endoscopic ultrasonography examination of the stomach.

RESULTS

Helicobacter pylori was eradicated in 45 of 51 (88%) patients. At the 2-year follow-up, complete regression of mucosa-associated lymphoid tissue lymphoma was seen in 28 of 51 (55%) patients: 12 of 16 (75%) patients in stage T1m N0, 11 of 19 (58%) patients in stage T1sm N0, four of eight (50%) patients in stages T1m N1 and T1sm N1, and one of four (25%) patients in stage T2 N0. None of the stage T2 N1 patients achieved clinical regression.

CONCLUSIONS

Endoscopic ultrasonography evaluation of gastric mucosa-associated lymphoid tissue lymphoma plays a pivotal role in the initial staging and post-treatment follow-up evaluation of these lesions. Accurate staging is essential in the determination of the optimal treatment modality.

The expression of proliferating cell nuclear antigen, p53, p21, and apoptosis in primary gastric lymphoma

BACKGROUND

We have investigated the correlations among the expression of proliferating cell nuclear antigen (PCNA), p53, p21, and the prognosis of primary gastric lymphoma, and we have investigated apoptosis by using transferase-mediated deoxyuridine triphosphate nick-end labeling staining.

METHODS

A retrospective study was performed on 33 cases of primary gastric lymphoma that were surgically resected. Histopathologic examination was undertaken according to the Working Formulation classification. Immunohistochemical staining was performed by using the avidin-biotin-peroxidase complex method, with anti-PCNA antibody, anti-p53 antibody, and anti-p21 antibody. Apoptosis was quantified in situ from paraffin-embedded specimens by using an in situ apoptosis detection kit.

RESULTS

On histologic grade, the survival rate of high-grade type was significantly lower than that of low-grade type and than that of intermediate-grade type. The PCNA index of low-grade type was significantly lower than that of intermediate-grade type and than that of high-grade type. Those patients who experienced recurrence were both p53(+) and p21(-). Two of these patients were receiving postoperative chemotherapy but nevertheless experienced recurrence at 18 months and at 5 months after surgery. The PCNA index of p53(+) p21(-) cases was significantly higher than that of p53(-) p21(+) cases. The apoptotic count of p53(-) p21(+) cases was significantly higher than that of p53(+) p21(-) cases.

CONCLUSIONS

The Working Formulation classification and the PCNA index were each significant factors predicting the prognosis of primary gastric lymphoma. The prognosis of p53(+) p21(-) cases was poor, and the apoptotic count of p53(+) p21(-) cases was low. Accordingly, the effect of combined chemotherapy for those cases was thought to be poor.

Molecular diagnostics in low-grade gastric marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue type after Helicobacter pylori eradication therapy

The primary gastric lymphomas are extranodal non-Hodgkin's lymphomas that likely originate from the mucosa-associated lymphoid tissue (MALT). Data suggest that chronic infection with Helicobacter pylori (H pylori) is significantly associated with the pathogenesis of low-grade gastric MALT lymphomas. This is in keeping with the observation that many patients with early low-grade MALT lymphomas have complete remissions after H pylori eradication therapy. However, the stability of these remissions remains unclear and relapses have been reported. It can be difficult to distinguish between early malignant and benign disorders of the gastric mucosa. A polymerase chain reaction (PCR) assay can detect rearrangements of the variable region of immunoglobulin heavy chains. This assay can be used to distinguish the clonality of B lymphocytes and has been investigated as a test for differential diagnosis of MALT lymphomas. Monoclonality is observed in the majority of MALT-lymphoma samples at diagnosis but has been found in gastritis samples as well. Whether the presence of monoclonal B cells is associated with the risk of lymphoma progression remains unclear. As many as 50% of patients who have complete histologic remissions of MALT lymphoma after H pylori eradication therapy have persisting monoclonal bands in follow-up PCR monitoring. Although it is unclear as to whether monoclonality indicates the presence of minimal residual disease, patients who have persistent monoclonal bands during follow-up should be considered at risk for relapse. The PCR assay for rearrangements of the variable region of the immunoglobulin heavy-chain gene appears to be of low value in the diagnosis of B-cell malignancies but could provide a useful tool in the follow-up of patients who achieve remissions after H pylori eradication.

Complete remission of primary high-grade B-cell gastric lymphoma after cure of Helicobacter pylori infection

PURPOSE

Treatment of low-grade gastric mucosa-associated lymphoid tissue lymphoma by eradication of Helicobacter pylori is reported to result in complete lymphoma remission in approximately 75% of cases. The effect that cure of the infection has on the course of a primary high-grade gastric lymphoma is largely uncertain. The aim of this study was to report the effect of cure of H pylori infection exerted in patients with high-grade B-cell gastric lymphoma.

PATIENTS AND METHODS

Eight patients (4 males and 4 females; age range, 26 to 85 years) with H pylori infection and high-grade lymphoma received eradication therapy before planned treatment. The effect of H pylori eradication on the course of high-grade lymphoma was assessed by analysis of surgical specimens (n = 2) or endoscopic biopsies (n = 6).

RESULTS

H pylori eradication was successful in all patients and led to complete remission of the lymphoma in seven patients. One patient has experienced partial remission. Two patients were referred to surgery, one of whom (stage II(1E)) had lymph node involvement, and the histologic work-up of the resected stomach revealed residual infiltrates of a low-grade lymphoma, which prompted consolidation chemotherapy. In one patient (initially stage I(1E)), abdominal lymphoma developed 6 months after eradication therapy, which regressed completely after chemotherapy. In four patients, no further treatment was given. Six patients continue in complete remission (range, 6 to 66 months).

CONCLUSION

Primary high-grade B-cell gastric lymphoma in stages I(E) through II(E1) associated with H pylori may regress completely after successful cure of the infection. Prospective trials are needed to investigate this treatment in larger numbers of patients.