Synchronous Occurrence of Splenic Pleomorphic Mantle CellLymphoma and Esophageal Adenocarcinoma withOverexpression of BCL1 Protein

Synchronous occurrences of mantle cell lymphoma (MCL), or intermediate lymphocytic lymphoma, and other malignancies arerare. Such cases present diagnostic and especially therapeutic challenges, making them of particular interest to study. We reporta case of synchronic MCL and an esophageal tumor in an elderly male patient. Morphologically, the tumors were classified assplenic pleomorphic MCL and adenocarcinoma of the esophagus occurring concurrently. The pleomorphic MCL mimickeddiffuse large B cell lymphoma (DLBCL) but lacked larger centroblast- or immunoblast-like cells. Curiously, both tumorsoverexpressed cyclin D1 by immunohistochemistry. This is an important feature that distinguishes MCL pathologically fromtwo of its closest entities in the differential diagnosis: chronic lymphocytic leukemia and DLBCL, the latter of which mantle cellscannot transform into. The lymphoproliferation revealed IGH/CCND1 translocation by FISH, but the esophagealadenocarcinoma only showed CCND1 aneuploidy without break-apart signals. Since the gastrointestinal (GI) tract is a commonsite of extranodal involvement by MCL and lymphomatous polyposis can present as GI polyps, adequate care was taken todifferentiate the esophageal adenocarcinoma from advanced stagings of MCL, as well as metastatic adenocarcinoma. Despitenumerous immunohistochemical stainings studied, only BCL1 was demonstrated to have partial overlap in both tumors. Thepatient underwent esophagectomy and splenectomy. A subsequent metastatic primary lung squamous cell carcinoma wasdiagnosed, after which the patient expired. MCL typically presents at an advanced stage and has been deemed incurable with aprognosis of only several years. It is unclear whether the patient succumbed to complications of his MCL or the metastaticsquamous cell carcinoma. Furthermore, he was lost to follow-up for a year and only received treatment after his third cancerwas diagnosed. We have reviewed previous reports of synchronic mantle cell lymphoma and other solid tumors orhematological malignancies in the literature.