Collision tumors: pancreatic adenocarcinoma and mantle cell lymphoma.

CONTEXT: Collision tumors are very rare entities composed of two or more distinct tumor components, each separated by normal tissue. Perhaps due to technical advances in the last decade, the incidence of collision tumors has been on the rise. To the best of our knowledge, collision tumors featuring mantle cell lymphoma and pancreatic adenocarcinoma have not been previously described in the scientific literature. CASE REPORT: For the first time, we describe herein the clinical course of a collision tumor between pancreatic adenocarcinoma and mantle cell lymphoma. DISCUSSION: We hypothesize several aspects in the pathogenesis of a such event and review the existing literature on collision tumors.

Autoimmune manifestations in patients with Waldenström macroglobulinemia.

Waldenström macroglobulinemia represents a lymphoplasmacytic lymphoma with an indolent clinical course. The existing literature associates this hematologic malignancy with various autoimmune disorders. Notwithstanding, these autoimmune conditions have not been comprehensively characterized or systematized to date. As a result, their clinical implications remain largely unknown. The authors offer a comprehensive review of the existing literature on various hematologic and nonhematologic autoimmune disorders documented in the course of Waldenström macroglobulinemia. Whereas some of them are thought to be secondary to a dysfunctional immune response associated with an underlying malignant process, others might be primary and might even play a role in its pathogenesis. Moreover, the observations that personal history and family history of certain autoimmune diseases were associated with an increased risk of subsequent Waldenström macroglobulinemia strengthen further the hypothesis that shared susceptibility genes and chronic antigenic stimulation might predispose individuals to both conditions.