Mucosa-associated lymphoid tissue (MALT) lymphoma arising in the esophagus, stomach, and lung

A 62-year-old woman was referred to our hospital for further investigation of slow-growing gastrointestinal submucosal tumors (SMTs) and multiple lung nodules. Esophageal SMTs had been identified 6 years earlier, following which lung tumors and gastric SMTs had subsequently developed. Despite repeated endoscopic biopsies, these SMTs could not be diagnosed definitively. Moreover, we were unable to detect any serological abnormalities or radiologic findings such as lymph node swelling. Thoracoscopic excision of a lung nodule led to the definitive diagnosis of mucosaassociated lymphoid tissue (MALT) lymphoma. Cytological findings of aspiration biopsy specimens from the esophagus and stomach were compatible with that of the lung nodule. To our knowledge, this is the first case report of esophageal MALT lymphoma with lung and gastric involvement. We discuss this extremely rare disease with reference to the relevant literature.