CLL/SLL with Interfollicular Distrbution

Lessons From the Friday Unknowns

Histologic sections show a large lymph node in which the architecture is almost completely replaced by lymphoma. The neoplasm surrounds a few residual reactive germinal centers. At low power magnification, pale areas can be appreciated consistent with proliferation centers. These areas are composed of small lymphocytes, prolymphocytes and paraimmunoblasts. The remainder of the neoplasm is composed mostly of small round lymphocytes. There are no areas of necrosis and the mitotic rate appears to be low.