Atypical Lymphoid Proliferations

The Pathologist's Viewpoint

Mahmoud Rezk Abdelwahed Hussein


Expert Rev Hematol. 2013;6(2):139-153. 

In This Article

Expert Commentary

In the author's opinion, we should not adhere to the notion that all lymphoproliferative lesions are readily classifiable or unequivocally benign (reactive hyperplasia and lymphadenitis) or malignant lymphomas. Such notion ignores the fact that the neoplastic transformation is a multistep process and the cell population acquires characteristics of malignancy over time. Therefore, a third category should exist that represents equivocal lesions – AtLP. AtLP defies easy classification on clinical and pathologic basis into either benign (reactive hyperplasia and lymphadenitis) or malignant lymphomas. The theme common to AtLP is lesions with some worrisome immunomorphologic and molecular changes. However, these features are insufficient for the diagnosis of lymphoma. As such, AtLP pose challenging diagnostic constraints and their diagnosis requires careful correlation of clinical, immunohistochemical and molecular findings. Some of these lesions may have an aggressive biologic course. The author would like to emphasize that sometimes AtLP are not necessarily premalignant and may very well represent a fully benign situation mimicking malignancy.