Benefit of volumetric-modulated arc therapy over three-dimensional conformal radiotherapy for stage I-II extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue in the stomach: a dosimetric comparison

PURPOSE: To retrospectively analyze dosimetric parameters of volumetric-modulated arc therapy (VMAT) and three-dimensional conformal radiotherapy (3D-CRT) delivered to extranodal marginal zone B-cell lymphomas of mucosa-associated lymphoid tissue in the stomach (gastric MALT lymphoma) to find out advantages of VMAT and conditions for definite benefits of VMAT. MATERIALS AND METHODS: Fifty patients with stage I-II gastric MALT lymphoma received VMAT (n = 14) or 3D-CRT (n = 36) between December 2005 and April 2018. Twenty-seven patients were categorized according to whether the planning target volume (PTV) overlaps kidney(s). Dosimetric parameters were analyzed by dose-volume histogram. RESULTS: Radiation dose to the liver was definitely lower with VMAT in terms of mean dose (p = 0.026) and V15 (p = 0.008). The V15 of the left kidney was lower with VMAT (p = 0.065). For those with PTV overlapping kidney(s), the left kidney V15 was significantly lower with VMAT. Furthermore, the closer the distance between the PTV and kidneys, the less the left kidney V15 with VMAT (p = 0.037). Delineation of kidney(s) by integrating all respiratory phases had no additional benefit. CONCLUSIONS: VMAT significantly increased monitor units, reduced treatment time and radiation dose to the liver and kidneys. The benefit of VMAT was definite in reducing the left kidney V15, especially in geometrically challenging conditions of overlap or close separation between PTV and kidney(s).

The Expression and Clinical Significance of HBD-2 in Gastric Mucosa of H. pylori Associated Gastric MALT Lymphoma / 天津医药

Objective To investigate the expression of humanβ-defensin 2 (HBD-2) in gastric mucosa of Helico-bacter pylori (H. pylori) associated gastric mucosa-associated lymphoid tissue (MALT) lymphoma, and the role of HBD-2 in gastric MALT lymphoma. Methods Forty gastric mucosa specimens from patients with H. pylori associated gastric MALT lymphoma were collected. And 36 gastric mucosa specimens from chronic superficial gastritis without H. pylori infection were included as control group. The expression of HBD-2 was detected by immunohistochemistry staining. Results The ex-pression of HBD-2 was significantly higher in H. pylori associated gastric MALT lymphoma than that of control group. (P＜0.01). The expression of HBD-2 was significantly decreased after the eradication of H. pylori (P＜0.01). The expression of HBD-2 was significantly higher in H. pylori associated gastric MALT lymphoma than that of lymphoma cells (P＜0.01). There was no expression of HBD-2 in lymphoma cells. Conclusion HBD-2 is possibly involved in the pathogenesis of H. pylori associated gastric MALT lymphoma. But whether it has anti-tumor effect is not clear.

Pathophysiology of Gastric MALT Lymphoma / 대한내과학회지

Early gastric mucosa-associated lymphoid tissue (MALT) lymphoma is considered as an antigen-dependent disease associated with long standing antigenic stimulation by Helicobacter pylori (H. pylori) which induces chronic immune response and lymphoid tissue development at the gastric mucosa normally devoid of lymphoid tissue. With disease progression, antigen-independent clones occur via genetic alterations inducing aberrant activation of nuclear factor kappaB (NF-kappaB) pathway which is essential for regulation of normal lymphocyte development and activation. Four major translocations, including t (11;18)/API2-MALT1, t (1;14)/BCL10-IGH, t (14;18)/(IGH-MALT1 and t (3;14)/FOXP1-IGH, occur mutually exclusively and lead to generation of cIAP2-MALT1 fusion protein or overexpression of BCL10, MALT1 and Foxp1. Translocation t (3;14)(q27;q32)/BCL6-IGH and t (1;2)(p22;p12)/BCL10-IGkappaL also occur in some MALT lymphomas. Mutational inactivation of A20, global NF-kappaB inhibitor, involve the development of especially translocation-negative MALT lymphoma. Downstream effects of most genetic alteration converge on the same NF-kappaB mediated oncogenic pathway. This review discusses the current advances in the pathophysiology underlying the development of gastric MALT lymphoma and its progression.

Role of Chemotherapy in Gastric Marginal Zone B-Cell Lymphoma of Mucosa-Associated Lymphoid Tissue (MALT) Type / 대한내과학회지

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma comprises approximately 50% of primary gastric lymphoma. Currently, Helicobacter pyroli eradication is the mainstay in the management of localized gastric MALT lymphoma. However, other treatment strategies such as radiotherapy and chemotherapy should be required in certain circumstances which include H. pyroli-negative disease, H. pyroli-positive disease unresponsive to standard eradication, and advanced disease (stage III/IV). Here, we reviewed the role of chemotherapy in the management of patients with gastric MALT lymphoma based on recent clinical trials.

Linfoma MALT gástrico, gastritis linfocitaria y enfermedad celíaca: caso clínico con seguimiento a largo plazo, post erradicación de Helicobacter pylori y regresión del MALT. Correlación Clínico-Endoscópica-Patológica / Gastric MALT lymphoma, lymphocytic gastritis and celiac disease: case report with long-term follow-up post helicobacter pylori eradication and regression of MALT: clinical-pathological and endoscopic correlation

A case report of 61 year old female patient with diarrhea syndrome, whose study showed the presence of low-grade MALT gastric lymphoma associated with lymphocytic gastritis and celiac disease. During a six-year period of follow-up, the eradication of Helicobacter pylori determined the remission of the gastric lymphoma and lymphocytic gastritis; celiac disease showed variable activity according to their adherence to dietary treatment. We discuss possible associations and etiology of MALT lymphoma and lymphocytic gastritis, and of the latter with celiac disease.

Se presenta caso de paciente mujer de 61 años con cuadro de síndrome diarreico, cuyo estudio demuestra la presencia de linfoma MALT de bajo grado asociado a gastritis linfocitaria y enfermedad celíaca. Durante su seguimiento de 6 años, la erradicación de Helicobacter pylori, determinó la remisión del linfoma y gastritis linfocitaria, mientras la enfermedad celíaca mostró actividad variable de acuerdo con su adherencia al tratamiento dietético. Se discuten las posibles asociaciones y etiología de linfoma MALT y gastritis linfocitaria, y de esta última con enfermedad celíaca.

Treatment and Prognosis of Gastric MALT Lymphoma

Mucosa-associated lymphoid tissue (MALT) lymphomas represent 7% of all non-Hodgkin's lymphomas and can arise from any extranodal site; however, at least one-third of them present as a primary gastric lymphoma. Eradication of Helicobacter pylori (H. pylori) with antibiotics should be employed as the sole initial treatment of H. pylori-positive gastric MALT lymphoma. H. pylori eradication can induce lymphoma regression and long-term clinical disease control in most patients. In H. pylori-negative cases or patients who fail antibiotics therapy, irradiation and systemic therapies should be applied depending on the stage of disease; surgery has not been shown to achieve superior results in comparison with more conservative approaches in various trials. Lymphoma with diffuse large cell infiltration should be treated according to the recommendations for diffuse large cell lymphoma. H. pylori eradication resulted in complete lymphoma remission in the majority of cases. Most patients with minimal histological residuals of gastric MALT lymphoma after successful eradication of H. pylori had a favorable disease course without oncological treatment. A watch and wait strategy with regular endoscopies and biopsies appears to be safe and may become the approach of choice in this situation. Nevertheless, long-term careful endoscopic and systemic (blood counts and minimal adequate radiological or ultrasound examinations) follow-up once per year is recommended for all patients. This article is a review for the current treatment and prognosis of gastric MALT lymphoma.

Diagnosis and Treatment of Gastric MALT Lymphoma / 대한소화기학회지

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma represents approximately 40% of gastric lymphomas, and its incidence is increasing. An early diagnosis for gastric MALT lymphoma is important, but not easy due to non-specific symptoms and endoscopic findings. Diagnosis is based on the histopathologic evaluation of multiple, deep and repeated biopsies taken from normal and any abnormal appearing sites of the stomach. In addition, the presence of Helicobacter pylori (H. pylori) infection must be determined to determine therapeutic approach. Endoscopic ultrasonography (EUS) is essential for the evaluation of regional lymph nodes and the depth of tumor invasion in the gastric wall, for predicting response to H. pylori eradication, and for monitoring tumor regression or recurrence. The eradication of H. pylori is recommended as an initial treatment for low-grade gastric MALT lymphoma with H. pylori infection. Both radiation therapy and chemotherapy are suitable alternative options for H. pylori-negative, refractory, or high-grade gastric MALT lymphoma. But, the role of surgery is diminishing. After treatment, strict endoscopic regular follow-up including EUS is recommended with multiple biopsies. However, controversy remains regarding the best diagnosis, treatment and follow-up strategy for this disease.

A Case of Gastric Low-grade MALT Lymphoma Induced by a Helicobacter heilmannii-like Organism / 대한소화기내시경학회지

Helicobacter heilmannii is a Gram negative, long spiral-shaped organism associated with zoonotic infections acquired from primates including cats and dogs. Infection with H. heilmannii leads to gastritis, peptic ulcer disease, gastric adenocarcinoma, and gastric mucosa-associated lymphoid tissue (MALT) lymphoma. We experienced a 54-year-old man with dyspepsia who was diagnosed with primary gastric MALT lymphoma (stage IE1) associated with a H. heilmannii-like organism. Upper gastrointestinal endoscopy revealed only microvascular dilatation and mucosal granularity without elevated or ulcerative lesions at the stomach angle. He was probably infected by a pet dog. The man was treated with eradication therapy for 2 weeks including lansoprazole, amoxicillin, and clarithromycin. Four weeks after eradication of the H. heilmannii-like organism, follow-up endoscopy and pathological biopsy findings showed complete remission of the gastric MALT lymphoma.

Linfoma gástrico tipo malt presentación de un caso

Paciente femenina, raza blanca, de 50 años de edad, que acudió a consulta de gastroenterología de la clínica Popular „Simón Bolívar‰ remitida de su área de salud, por presentar dolor abdominal de tipo epigastralgias, de moderada intensidad, de 2 meses de evolución, con sensación de ardor, además de aparecer más recientemente náuseas y vómitos post-prandiales. La endoscopia superior evidenció lesiones nodulares del fondo y ulcerada del cardias, el estudio histopatológico con inmunohistoquímica reveló linfoma no Hodgkin de células B extranodal, del tejido linfoide asociado a mucosa (MALTOMA). Cumplió tratamiento erradicador para el Helicobacter pylori. Las endoscopias evolutivas mostraron evidente mejoría. Catorce meses después, la evaluación histopatológica reportó gastritis crónica atrófica sin atipias, ausencia de infección por Helicobacter pylori. Actualmente está asintomática y tiene seguimiento semestral.

Female patient, Caucasian, 50 years old, who turned up for Gastroenterology consult of the „Simon Bolivar‰Popular Clinic, remitted from their health area , because of epigastric abdominal pain of moderate intensity with two months of evolution, with burning sensation, besides nauseas and vomiting. The upper digestive endoscopy showed a big ulceration in the cardial portion and granulate mucosa in the bottom of stomach. The histological study with inmunohistochemistry revealed a B extranodal cell non Hodgkin lymphoma of mucosa-associated lymphoid tissue (MALT). She completed treatment for eradication of Helicobacter pylori . Fourteen months later, the histopathologic evaluation reported a chronic atrophic gastritis without atypical cells and an absence of infection for Helicobacter pylori. At the moment she is asymptomatic and has a biannual follow-up.

Low-grade Mucosa-associated Lymphoid Tissue Lymphoma of Stomach / 대한소화기학회지

Stomach is the most common site of primary extranodal lymphoma. Mucosa-associated lymphoid tissue (MALT) lymphoma is a unique type of extranodal lymphoma which is associated with Helicobacter pylori (H. pylori). The development of low-grade MALT lymphoma of stomach is dependent on H. pylori. A transformed clone carrying the translocation t(11;18)(q21;q21) forms a MALT lymphoma, the growth of which is independent of H. pylori and will not respond to bacterial eradication. And inactivation of the tumor suppressor genes, p53 can lead to high-grade transformation. Endoscopic ultrasound (EUS) is essential to document the extent of disease and is superior to CT scan in the detection of spread to perigastric lymph nodes and follow-up EUS may determine the response to therapy and detect the relapse in early phase. Lesions that are confined to the mucosa or submucosa of gastric wall can be successfully treated with H. pylori eradication. Those low-grade MALT lymphomas that are not H. pylori positive or do not respond to antibiotic therapy can be treated with surgery, radiation, or chemotherapy. Follow-up is critical in all patients who have been treated with H. pylori eradication and consists of multiple endoscopic biopsies and EUS.

A Case of Gastric MALT Lymphoma Presenting as a Submucosal Tumor (SMT)-like Lesion, Diagnosed by Endoscopic Mucosal Resection / 대한소화기내시경학회지

Gastric MALT lymphoma usually presents with various endoscopic morphologic characteristics. The majority of gross findings reveal multiple and superficial erosions or ulcerations. However gastric MALT lymphoma, presenting as a submucosal tumor, is very rare. We recently experienced a case of low-grade gastric MALT lymphoma, presenting as a submucosal tumor-like lesion without definite mucosal lesion, confirmed by endoscopic mucosal resection. So we report this case with a review of the related literatures.

Endoscopic Findings and Results of Long-term Follow-up of Low Grade Gastric MALT Lymphoma / 대한소화기내시경학회지

BACKGROUND/AIMS: We aimed to evaluate the long-term outcome of patients with MALT lymphoma in respect to various treatment modalities and clinicopathologic characteristics, including endoscopic findings. We also tried to deduce suitable strategic guideline to treat MALT lymphoma. METHODS: We retrospectively studied 55 patients (24 males and 31 females) aged 23 to 74 years who had primary low-grade gastric MALT lymphoma that were diagnosed between May 1992 and August 2002. RESULTS: The majority of endoscopic findings showed lesions with ulceration or with color and surface change of mucosa. All but one was H. pylori positive when tested. Treatment modalities included anti H. pylori treatment, radiation, surgery and/or chemotherapy. Eradication was successful in all the 29 patients associated with H. pylori infection. Complete remission was obtained in 24 patients (82.8%). Only one patient suffered a relapse after 28 months during the follow up (2~74 months). The duration to reach complete remission was 12 months (85 percentile, 2~33 months). Six patients showed complete remission with radiation therapy. Two of them were H. pylori treatment failure cases. One of 14 patients treated by surgery displayed relapse during follow-up (12~20 months). Endoscopically, the ulcerative and/or the protruding type showed unfavorable response to anti H. pylori treatment. CONCLUSION: H. pylori eradication alone should be considered as an initial treatment for MALT lymphoma and radiation therapy could be preferred in patients with no evidence of H. pylori infection or who do not response to H. pylori eradication therapy 12 months after successful eradication.