Rapidly progressing primary pulmonary lymphoma masquerading as lung infectious disease: A case report and review of the literature

Figure 2 Pathological images of lung tissue biopsy at day 5 of hospitalization. A: Hematoxylin-eosin staining showed the alveolar structure of the lung tissue with massive infiltration by large anaplastic lymphocytes in the alveolar septum with scattered neutrophils. Magnification, 400 ×; B-J: Immunostaining revealed that the tumor cells were ALK(+) (anaplastic lymphoma kinase) (B), CD3(-) (C), CD4(-) (D), CD5(-) (E), CD7(+) (F), CD8(-) (G), CD20(-) (H), CD30 (+) (I), and Ki-67(+) (J). Magnification, 400 ×.