The patient refused either radiation therapy or
The patient refused either radiation therapy or systemic chemotherapy including rituximab and thus was initially treated with antibacterial therapy for HP infection. The first-line therapy consisted of lansoprazole 30mg, amoxicillin 750mg, and clarithromycin 200mg twice daily for 1 week. After 2 months of treatment, the 13C-urea breath test remained positive, although follow-up EGD and CT scanning showed complete disappearance of the mass (Fig. 1B). A second course of HP eradication therapy was administered, consisting of lansoprazole 30mg, amoxicillin 750mg, and metronidazole 250mg twice daily for 1 week. The SAR 405 pump inhibitor was discontinued after the second course of therapy. The second 13C-urea breath test performed 9 weeks after the second course of eradication therapy was negative. She has remained in complete remission for more than 3 years.
Discussion In a PubMed literature search, 37 PEL cases in stage I, without HIV infection, were reported in English and Japanese. The median age was 59 (range, 17–83) years with male dominancy (male: female=25:13). Although PEL had various tissue types, only 12 (32.4%) primary esophageal MALT lymphomas in stage I were reported (Table 1). Only one primary esophageal MALT lymphoma case with HP infection from other institution was reported in addition to ours. Localized gastric MALT lymphoma with HP infection without t(11;18) translocation was reported to regress completely after HP eradiation therapy , and HP-negative gastric MALT lymphoma patients were treated with local radiation therapy or endoscopic mucosal resection, while a few received systemic chemotherapy. On the other hand, no standard treatment has been established for patients with localized primary esophageal MALT lymphoma. Six of 12 reported cases were treated with endoscopic resection, and 2 patients received rituximab therapy consisting of rituximab alone for one and rituximab in combination with radiation for the other (Table 1). Three patients with HP infection were treated with HP eradication therapy and either rituximab or resection or resection+radiation. Because no patient was treated with HP eradication alone among the previous reports, the role of HP eradication is unclear in esophageal MALT lymphoma. All PEL cases were reported to survive, although the observation periods were short. MALT lymphoma has been reported to occur in sites with chronic inflammation, i.e., the stomach and salivary and thyroid glands. According to the evidence, primary esophageal MALT lymphoma might also be associated with some type of inflammation. However, the relationship between esophageal MALT lymphoma and local inflammation remains unclear. HP is reported to be associated with an increased risk of gastric malignancies and a decreased risk of esophageal adenocarcinoma . HP infection in the esophagus was reported in Barrett\'s esophagus and squamous cell carcinoma [5,6]. Although it remains unclear whether HP infection is associated with the pathogenesis of primary esophageal MALT lymphoma, MALT within Barrett\'s esophagus was associated with esophageal HP infection in 57% of cases and gastric HP infection in 71%; HP was found in approximately one-third of Barrett\'s esophagus patients . In our patient, Barrett\'s esophagus and esophageal HP infection were not observed, but eradication therapy induced complete remission. Although it is not known how non-gastric MALT lymphoma regression is achieved via the elimination of HP infection, previous reports indicated that MALT lymphoma in the rectal and salivary glands showed regression after HP eradication therapy [8,9]. Those reports including ours suggest that HP may be involved in the pathogenesis of non-gastric MALT lymphoma, although the underlying mechanism remains unclear. Furthermore, in our case, the MALT lymphoma resolved after the first round of HP eradication therapy without complete eradication. The first course of therapy decreased the gastric HP bacterial load as detected by the pathological findings, suggesting that the effect of HP requires a certain level of bacterial burden . To elucidate the mechanism of occurrence of primary esophageal MALT lymphoma, it will be important to accumulate more information on and to investigate those patients.