Kojima Masaru, Yamanaka Shouji, Yoshida Takatomo, Shimizu Ken, Murayama Kayoko, Ohno Yoshihiro, Itoh Hideaki, Motoori Tadashi, Masawa Nobuhide, Nakamura Shigeo
Pathology and Clinical Laboratories, Gunma Cancer Center Hospital, 617-1 Takabayashinishi-cho, Ohta 373-8550, Japan.
APMIS. 2006 Sep;114(9):626-32. doi: 10.1111/j.1600-0463.2006.apm_424.x.
To further clarify the histopathological findings of the floral variant of follicular lymphoma (FVFL), we studied 13 Japanese cases. Two histological subtypes of neoplastic follicles of FVFL have been described: (i) A macrogerminal center pattern where the mantle zone lymphocytes were invaginated into the neoplastic germinal center, often reminiscent of a floral design. (ii) A microgerminal center pattern where the massive invasion of mantle zone lymphocytes resulted in almost complete breakage of the neoplastic follicles. In the former pattern, the neoplastic germinal center usually contained large clusters of tumor cells, whereas in the latter, small clusters of up to 20 tumor cells or isolated tumor cells were observed in the neoplastic germinal centers. Moreover, occasional tumor cells showed a lymphocytic and/or histiocytic Reed-Sternberg cell (L&H cells)-like morphology. Both types of neoplastic follicles were observed to a varying degree in most cases. The macrogerminal center pattern was predominant in nine cases (70%), whilst the microgerminal center pattern was predominant in only four cases (30%). Three lesions (23%) had a marginal zone component. Immunohistochemistry showed that atypical follicular center cells, including L&H cells, were CD3-, CD5-, CD10+, CD20+, CD43-, bcl-2+, cyclinD1-. The overall histological findings of the macrogerminal center are similar to those of florid progressive transformation of germinal center (PTGC), whilst the microgerminal center pattern is similar to that of nodular lymphocyte-predominant Hodgkin lymphoma. Initially, the differential diagnosis between FVFL and florid PTGC was emphasized. However, the present study indicates that nodal marginal zone B-cell lymphoma possessing floral follicles and nodular lymphocyte-predominant Hodgkin lymphoma should be added to the differential diagnosis of FVFL. The germinal center B-cell nature of FVFL is most clearly recognizable by immunohistochemistry, though histological appearance alone may cause some diagnostic problems.
为进一步阐明滤泡性淋巴瘤花型变体（FVFL）的组织病理学特征，我们研究了13例日本患者。FVFL肿瘤性滤泡的两种组织学亚型已被描述：（i）大生发中心型，套区淋巴细胞侵入肿瘤生发中心，常使人联想到花朵图案。（ii）小生发中心型，套区淋巴细胞大量浸润导致肿瘤滤泡几乎完全破裂。在前一种类型中，肿瘤生发中心通常包含大量肿瘤细胞簇，而在后一种类型中，肿瘤生发中心可见小至20个肿瘤细胞的簇或单个肿瘤细胞。此外，偶尔可见肿瘤细胞呈现淋巴细胞和/或组织细胞性里德-施特恩贝格细胞（L&H细胞）样形态。大多数病例中两种类型的肿瘤滤泡均有不同程度的出现。大生发中心型在9例（70%）中占主导，而小生发中心型仅在4例（30%）中占主导。3个病灶（23%）有边缘区成分。免疫组化显示，包括L&H细胞在内的非典型滤泡中心细胞CD3-、CD5-、CD10+、CD20+、CD43-、bcl-2+、cyclinD1-。大生发中心的总体组织学表现与生发中心的 florid进行性转化（PTGC）相似，而小生发中心型与结节性淋巴细胞为主型霍奇金淋巴瘤相似。最初，强调了FVFL与 florid PTGC之间的鉴别诊断。然而，本研究表明，具有花型滤泡的淋巴结边缘区B细胞淋巴瘤和结节性淋巴细胞为主型霍奇金淋巴瘤也应列入FVFL的鉴别诊断。尽管仅凭组织学表现可能会导致一些诊断问题，但FVFL的生发中心B细胞性质通过免疫组化最易识别。
