Mucosa-associated lymphoid tissue (MALT) lymphoma, a type of non-Hodgkin lymphoma, originates in the mucosal lining of body organs and internal cavities, including the nose, mouth, lungs, and digestive tract. The lymphoma develops when the body produces abnormal B lymphocytes. These lymphomas develop at the edge of the lymphoid tissue, called the marginal zone, and, hence, are classified as a type of marginal zone lymphomas. They are the most common type of marginal zone lymphomas although their occurrence is rare. To date, no previous cases of MALT lymphoma in the buccal fat pad have been reported.

We report the case of a patient who presented with a mass on the frontal cheek. Magnetic resonance imaging revealed a tumor in the buccal fat pad, and histopathological and immunohistochemical findings confirmed the diagnosis of MALT lymphoma. The patient had a history of Helicobacter pylori and hepatitis C virus infection, suggesting an association between these infective agents and MALT lymphoma.

Consideration of MALT lymphoma is essential in the differential diagnosis of frontal cheek masses.

Duodenal mucosa-associated lymphoid tissue (MALT) lymphoma is an extremely rare tumor. Herein, we report multidisciplinary treatment of a patient with synchronous development of primary MALT lymphoma of the duodenum and gastric cancer. A 70-year-old woman was referred to our hospital for examination of a gastric cancer initially diagnosed by a local medical doctor. Esophagogastroduodenoscopy showed an elevated lesion with a central ulcer in the lower body of the stomach, and a partially whitish aggregated lesion in the descending portion of the duodenum. Histopathological examination of biopsy specimens from the gastric lesion showed moderately differentiated adenocarcinoma, and duodenal specimens showed low-grade MALT lymphoma composed of atypical lymphoid cells with a lymphoepithelial lesion. The patient underwent distal gastrectomy with regional lymph node dissection for the gastric cancer. Histological examination showed muscularis propria invading adenocarcinoma with two lymph node metastases. After operation, four courses of systemic rituximab treatment were administered for the MALT lymphoma, followed by adjuvant S-1 (tegafur/gimeracil/oteracil) chemotherapy for the gastric cancer. In the 4 months after operation, the patient was well with no evidence of recurrence. To the best of our knowledge, this is the second reported case of synchronous gastric adenocarcinoma and duodenal MALT lymphoma in the English literature.

Clinical data regarding mucosa-associated lymphoid tissue lymphoma (MALToma) solely involving the duodenum are sparse because of the relative rarity of the disease. A comprehensive literature review revealed only 17 cases reported until 2004, and only a moderate number of cases have been reported since. MALToma can be asymptomatic in its very early stages but frequently produces localized or nonspecific symptoms, including early satiety, abdominal pain, vomiting, and involuntary weight loss in later stages. While gastric MALToma is strongly associated with gastric Helicobactor pylori infection, duodenal MALToma is often unassociated with H. pylori infection. A 74-year-old female presented with only dysphagia (without symptoms referable to a duodenal lesion), without systemic 'B' symptoms, and with no evident duodenal lesions at esophagogastroduodenoscopy; however, she was diagnosed with duodenal MALToma by pathologic examination of random duodenal biopsies performed to exclude celiac disease. An important clinical feature of this case is that duodenal MALToma was diagnosed by pathologic analysis of duodenal biopsies despite (1) no endoscopically apparent duodenal lesions; (2) duodenal involvement without gastric involvement; (3) lack of symptoms attributable to duodenal MALToma, and (4) absence of evident H. pylori infection. This work shows that early duodenal MALToma can be difficult to diagnose because of absent symptoms, absence of gastric involvement, absence of endoscopic abnormalities, and absence of H. pylori infection; it may require random duodenal biopsies for diagnosis.

Helicobacter pylori-related extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue is a paradigm for malignancy arising in an inflammatory background. While the diagnosis of H. pylori gastritis is often straightforward, distinction between severe gastritis and early lymphoma can be difficult and requires careful assessment of clinical findings in addition to histological features and immunohistochemical results. A number of cytogenetic abnormalities have been discovered in H. pylori-related lymphomas and several have clinical importance, related to the responsiveness of lymphoma to H. pylori eradication therapy, but routine molecular studies are not widely utilized. While molecular methods may be used in equivocal cases, a trial of conservative therapy is warranted given the propensity for these lymphomas to regress with eradication of the organism. Once therapy is initiated, care must be taken to avoid a premature assignment of disease refractoriness because complete response can take several months to more than a year. Cases truly refractory to H. pylori eradication therapy may be treated with adjuvant chemoradiation with a high response rate.

Duodenal mucosa-associated lymphoid tissue (MALT) lymphoma is very rare, and little is known about its clinical characteristics, endoscopic and endosonographic features, and treatment. We hereby report a case of duodenal MALT lymphoma successfully treated by radiation therapy (RT). The patient was referred to us with epigastric pain and positive fecal occult blood testing. His symptoms failed to resolve with eradication therapy for a Helicobacter pylori infection that was diagnosed by a gastric biopsy performed elsewhere. Endoscopy at our institution revealed hypertrophy of the duodenal folds with erosions involving a third of the circumference few centimeters beyond the ampulla of Vater. Histopathologic and immunophenotypic features were consistent with a MALT lymphoma. There was no evidence of a H. pylori infection by gastric biopsy and urea breath test. Computed tomography scan of the abdomen and pelvis was normal. Endoscopic ultrasound showed thickening of the duodenal wall and hypoechoic infiltration into the submucosal layer. The patient was treated with RT with a complete response. Two and a half years later, he remains in complete clinical, endoscopic, and histopathologic remission. This case illustrates the importance of RT in patients with duodenal MALT lymphoma whose disease did not respond to H. pylori eradication.

We aimed to estimate the frequency of association between non-Hodgkin lymphoma (NHL) with abdominal, gastric, or intestinal involvement and Helicobacter pylori in childhood. Between February 2003 and June 2006, we evaluated 15 children with newly diagnosed NHL who were diagnosed and treated at the Pediatric Oncology Department of Hacettepe University. Patients who were given chemotherapy previously or who received H. pylori eradication therapy were excluded from the study. Routine procedures were done for staging. Pathologic diagnosis was made by examining the biopsy samples. The presence of H. pylori was confirmed by H. pylori IgG serology with urea breath test (UBT) in cooperated children. Endoscopic examination was also planned for patients with positive test results. Twelve male and 3 female patients, with a median age of 7 (range: 3 to 16), were evaluated. They had extensive abdominal, gastric, and/or intestinal involvement. Six had stage IV characteristics, whereas another 9 patients had stage III disease. Ten had high-grade B-cell lymphoma. Only 3 patients had H. pylori IgG and UBT positivity (20%). First patient had T-cell lymphoma and stage IV disease with involvement in stomach, mediastinum, peripheral lymph nodes, and bone marrow. The second one had anaplastic large cell lymphoma exclusively in abdominal lymph nodes. Last patient had Burkitt lymphoma and stage IV disease, with primary tumor localization in abdominal lymph nodes, liver, and kidneys. The H. pylori IgG and UBT were both positive in 3 patients on admission. We did not find any positive test results in the other 12 patients with intestinal, stomach, or abdominal disease. Preliminary results of our study suggest that H. pylori may not be the responsible agent for NHL involved the abdomen in childhood.

Mucosa-associated lymphoid tissue (MALT) lymphoma of the papilla of Vater is rare, and little is known of either its association with Helicobacter pylori infection or the optimal treatment modalities. We describe the first case of MALT lymphoma involving the major papilla that remained unchanged despite eradication of H. pylori, but which regressed following radiotherapy. A 46-year-old asymptomatic man was admitted to hospital for treatment of MALT lymphoma involving the papilla of Vater. Duodenal endoscopy showed multiple granules around the major ampulla, and biopsies revealed mucosal proliferation of centrocyte-like cells, lymphoepithelial lesions, hyperplastic lymphoid follicles and plasmacytic differentiation. The lymphoma cells were positive for B-cell but negative for T-cell markers, and expressed Bcl-2 but showed no immunoreactivity for CD5, CD10 and cyclin D, consistent with MALT lymphoma. The patient was successfully treated with triple therapy of lansoprazole, amoxicillin and clarithromycin for 1 week for coexisting H. pylori infection in the stomach, but the lymphoma lesions remained unchanged. Then, involved-field irradiation was applied at a total dose of 30 Gy delivered in 1.5 Gy fractions without any adverse events. Six months later, repeat endoscopy revealed disappearance of the granular lesions and lack of lymphoma cells in biopsy specimens. Four years after the commencement of radiotherapy, the patient is still in complete remission. Radiotherapy seems a safe and effective treatment modality for low-grade MALT lymphoma of the ampulla of Vater.