Molecular pathogenesis of lymphomas of mucosa-associated lymphoid tissue--from (auto)antigen driven selection to the activation of NF-κB signaling

Gastric Cancer Vascularization and the Contribution of Reactive Oxygen Species

Blood vessels are the most important way for cancer cells to survive and diffuse in the body, metastasizing distant organs. During the process of tumor expansion, the neoplastic mass progressively induces modifications in the microenvironment due to its uncontrolled growth, generating a hypoxic and low pH milieu with high fluid pressure and low nutrients concentration. In such a particular condition, reactive oxygen species play a fundamental role, enhancing tumor proliferation and migration, inducing a glycolytic phenotype and promoting angiogenesis. Indeed, to reach new sources of oxygen and metabolites, highly aggressive cancer cells might produce a new abnormal network of vessels independently from endothelial cells, a process called vasculogenic mimicry. Even though many molecular markers and mechanisms, especially in gastric cancer, are still unclear, the formation of such intricate, leaky and abnormal vessel networks is closely associated with patients' poor prognosis, and therefore finding new pharmaceutical solutions to be applied along with canonical chemotherapies in order to control and normalize the formation of such networks is urgent.

Helicobacter pylori and unignorable extragastric diseases: Mechanism and implications

Considered as the most popular pathogen worldwide, Helicobacter pylori is intensively associated with diverse gastric diseases, including gastric ulcers, chronic progressive gastritis, and gastric cancer. Aside from its pathogenic effect on gastric diseases, growing evidences reveal that H. pylori may be related to numerous extragastric diseases. In this article, we reviewed recent studies and systematically elucidated that H. pylori may interfere with many biological processes outside the stomach and influence the occurrence of various extragastric diseases. Many epidemiological studies have indicated that H. pylori plays a pathogenic role in COVID-19, atherosclerosis, hyperemesis gravidarum and several other extragastric diseases, while the effect of H. pylori is currently under investigation in gastroesophageal reflux disease, asthma, and inflammatory bowel disease. Moreover, we also summarized the possible pathogenic mechanisms of H. pylori that may be related to chronic systemic inflammation and molecular mimicker. Taken together, this review provides a new perspective on the role of H. pylori in extragastric diseases and explores the possible mechanisms, which may help guide clinical treatment.

MALT lymphoma: epidemiology, clinical diagnosis and treatment

Primary gastric lymphoma (PGL) represents a rare pathology, which can be easily misdiagnosed because of unspecific symptoms of the digestive tract. Histologically, PGL can vary from indolent marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT) to aggressive diffuse large B-cell lymphoma (DLBCL). During the years, clinical trials revealed the important role of Helicobacter pylori (H. pylori) in the pathogenesis of gastric MALT lymphoma. Infection with Helicobacter pylori is an influential promoter of gastric lymphomagenesis initiation. Long-term studies revealed that eradication therapy could regress gastric lymphomas.

A single center experience: rituximab plus cladribine is an effective and safe first-line therapy for unresectable bronchial-associated lymphoid tissue lymphoma

BACKGROUND

Bronchial-associated lymphoid tissue (BALT) lymphoma is a relatively rare form of B-cell non-Hodgkin lymphoma (B-NHL). To date, the standard systemic treatment for this disease is still under debate, and few data are accessible for newly diagnosed unresectable BALT lymphoma presented with advanced disease. The combination of rituximab (R) and cladribine (2-CdA) has shown some activity in indolent B-NHL, but its usage has not been tested in disseminated BALT lymphoma so far.

METHODS

An observational retrospective study was performed on homogeneous data of 8 patients with biopsy-proven stage IV BALT lymphoma to assess the efficacy and the safety of R-2-CdA therapy. All but one of the patients received six courses of R-2-CdA regimen consisted of rituximab 375 mg/m² IV day 1 and cladribine 0.1 mg/kg IV days 1-4 every 21 days; one patient completed 4 cycles and received additional R maintenance.

RESULTS

A high overall response rate (ORR) was observed (100%), with 2 patients (25%) achieved a complete remission (CR), the remaining (75%) a partial response. Improvement of pulmonary function was observed in all tested patients. Grade 3 and 4 toxicities were leukocytopenia and neutropenia in 3 patients (37.5%), diarrhea in one (12.5%). Estimated two-year progression-free survival (PFS) and 2-yr overall survival (OS) were 80.0% (95% CI, 20.3-96.7%) and 100%, respectively.

CONCLUSIONS

R-2-CdA therapy demonstrated high activity and tolerable toxicity in chemotherapy-naïve patients with unresectable BALT lymphoma of advanced stage. Although further large-scale study is needed for consolidation, R-2-CdA regimen could be a good first-line therapy option for patients with unresectable BALT lymphoma.

Mucosa-associated lymphoid tissue lymphoma with unusual 18F-FDG hypermetabolism arising at the colorectal anastomosis

Mucosa-associated lymphoid tissue (MALT) lymphoma usually originates from the stomach and presents with low ¹⁸F-fluorodeoxyglucose (FDG) avidity with average maximum standard uptake value of 3.6. Colorectal MALT lymphoma is a rare entity that contributes to 1.6% of all MALT lymphomas and < 0.2% of large intestinal malignancies. The case reported herein firstly revealed stage IIE MALT lymphoma with unexpected higher ¹⁸F-FDG avidity of 18.9 arising at the colorectal anastomosis in a patient with a surgical history for sigmoid adenocarcinoma, which was strongly suspected as local recurrence before histopathological and immunohistochemical examinations. After accurate diagnosis, the patient received four cycles of standard R-CVP regimen (rituximab, cyclophosphamide, vincristine and prednisone), combined target therapy and chemotherapy, instead of radiotherapy recommended by National Comprehensive Cancer Network guidelines. He tolerated the treatment well and reached complete remission.