Anaplastic variant of diffuse large B-cell lymphoma with hallmark cell appearance: Two cases highlighting a broad diversity in the diagnostics

作者：Sakakibara Ayako; Kohno Kei; Kuroda Naoto; Yorita Kenji; Megahed Nirmeen A; Eladl Ahmed E; Daroontum Teerada; Ishikawa Eri; Suzuki Yuka; Shimada Satoko; Nakaguro Masato; Shimoyama Yoshie; Satou Akira; Kato Seiichi; Yatabe Yasushi; Asano Naoko; Nakamura Shigeo

来源：Pathology International, 2018, 68(4): 251-255.

DOI：10.1111/pin.12653

• anaplastic variant
• classic Hodgkin lymphoma
• diffuse large B-cell lymphoma
• gray zone lymphoma
• hallmark cell

The anaplastic variant of diffuse large B-cell lymphoma (A-DLBCL) is morphologically defined but remains an enigmatic disease in its clinicopathologic distinctiveness. Here, we report two cases involving Japanese women aged 59 years, both with A-DLBCL with the hallmark cell appearance and both indistinguishable from common and giant cell-rich patterns, respectively, of anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma. Case 1 was immunohistochemically positive for CD20, CD79a and OCT-2 but not for the other pan-B-cell markers, CD30 and ALK. Case 2 showed CD20 and CD30 positivity for 50% and 20% of tumor cells in addition to strong expression of p53 and MYC. Both were positive for fascin without Epstein-Barr virus association. Our cases provide additional support for the earlier reports that A-DLBCL exhibits clinicopathologic features distinct from ordinal diffuse large B-cell lymphoma (DLBCL), and documented its broader morphologic diversity than previously recognized. They also shed light on the unique feature of absent expression of pan-B-cell markers except for CD20 and CD79a, suggesting that A-DLBCL may biologically mimic a gray zone or intermediate lymphoma between DLBCL and classic Hodgkin lymphoma.

• 出版日期2018-4