ALK-positive anaplastic large cell lymphoma presenting multiple lymphomatous polyposis: A case report and literature review

Figure 4 Histopathological findings in biopsy samples (x 200), Medium to large-sized abnormal lymphoid cells with irregular nuclei grew diffusely (A), and mitotic figures were observed in high numbers (B). In immunostaining of lymphoma cells, CD30 was strongly positive (C), and ALK showed positive in nuclear and cytoplasmic patterns (D).