What is characterized by sheets of medium-sized lymphoid cells and a "starry sky" appearance on histology slides?

Burkitt's lymphoma is characterized by sheets of medium-sized lymphoid cells along with a distinct "starry sky" appearance observed on histological examination. This appearance is primarily due to the presence of macrophages that have phagocytosed apoptotic cells and debris, giving the tissue a mottled appearance when viewed under a microscope.

Rapid proliferation of B cells in Burkitt's lymphoma leads to this typical histological pattern. The "starry sky" effect is not only a hallmark of Burkitt's lymphoma but is also distinctive enough to help differentiate it from other types of lymphomas. The presence of medium-sized lymphoid cells contributes to the aggressive nature of this lymphoma, which is often associated with translocations involving the MYC oncogene, usually t(8;14).

Other types of lymphoma mentioned in the choices can present with different histological characteristics. For instance, Hodgkin's lymphoma typically shows Reed-Sternberg cells, while follicular lymphoma exhibits a more nodular architecture with small follicle-like structures. Diffuse large B-cell lymphoma has a diffuse pattern with larger, atypical cells but lacks the starry sky feature characteristic of Burkitt's lymphoma.