Coexistence of tumorlet and marginal zone B-cell lymphoma in the lung.

Extranodal marginal zone lymphoma (EMZL, MALT lymphoma) and carcinoid are neoplasms occurring most frequently in the gastrointestinal tract and respiratory system. Although each of them occurs relatively frequently and separately, the simultaneous appearance of these two neoplasms is exceptionally rare, and only a few cases in the gastrointestinal tract have been described so far. We report a case of a 70-year-old female with the simultaneous presence of MALT lymphoma and tumorlet in the middle lobe of the right lung. To the best of our knowledge, this is the first report of such a collision tumor at the same anatomical site.