Paulli Marco, Viglio Alessandra, Vivenza Daniela, Capello Daniela, Rossi Davide, Riboni Roberta, Lucioni Marco, Incardona Paolo, Boveri Emanuela, Bellosta Mario, Orlandi Ester, Borroni Giovanni, Lazzarino Mario, Berti Emilio, Alessi Elvio, Magrini Umberto, Gaidano Gianluca
Department of Pathology, IRCCS Policlinico S.Matteo/University of Pavia, Italy.
Hum Pathol. 2002 Sep;33(9):937-43. doi: 10.1053/hupa.2002.126881.
This study analyzes the pathologic and molecular features of 5 cases of primary cutaneous large B-cell lymphoma of the leg (PCLBCL-leg), recently included in the European Organization for Research and Treatment of Cancer (EORTC) classification of primary cutaneous lymphoma. PCLBCL-leg accounts for 5% to 10% of all primary cutaneous B-cell lymphoma (PCBCL), usually affects elderly patients and carries a worse prognosis than other forms of PCBCL. It has been proposed that the malignant cells of PCLBCL-leg originate from germinal center (GC)-related cells, but their effective normal counterpart is unclear, and the rationale behind the inclusion of this lymphoma as a separate entity is based on its prognosis rather than on its proved histogenesis. All of our cases of PCLBCL-leg morphologically resembled diffuse large B-cell lymphoma (DLBCL), but to better define their histogenesis, we also analyzed various phenotypic and genotypic markers, including mutations of the Ig and of BCL-6 genes, as well as expression of the bcl-6, MUM1, and CD138/syndecan-1 proteins. Immunohistochemically, all of our cases stained for the L-26/CD20cy and CD79a antigens and expressed the bcl-2, bcl-6, and MUM-1 proteins but were negative for both the CD10/CALLA and CD138 antigens. With respect to molecular analysis, the lymphoma population of all PCLBCL-leg carried hypermutation of Ig genes, and all but 1 case also harbored mutations of the BCL-6 gene. Our results indicate that PCLBCL-leg are similar both under the morphofunctional and molecular profiles to most DLBCL of other sites. Thus, caution seems justified before definitely considering PCLBCL of the leg as a distinct entity.
本研究分析了5例腿部原发性皮肤大B细胞淋巴瘤（PCLBCL-leg）的病理和分子特征，该类型最近被纳入欧洲癌症研究与治疗组织（EORTC）原发性皮肤淋巴瘤分类中。PCLBCL-leg占所有原发性皮肤B细胞淋巴瘤（PCBCL）的5%至10%，通常影响老年患者，且预后比其他形式的PCBCL更差。有人提出PCLBCL-leg的恶性细胞起源于生发中心（GC）相关细胞，但其有效的正常对应细胞尚不清楚，将这种淋巴瘤作为一个独立实体纳入的依据是其预后，而非已证实的组织发生学。我们所有的PCLBCL-leg病例在形态上类似于弥漫性大B细胞淋巴瘤（DLBCL），但为了更好地确定其组织发生，我们还分析了各种表型和基因型标志物，包括Ig和BCL-6基因的突变，以及bcl-6、MUM1和CD138/多配体蛋白聚糖-1蛋白的表达。免疫组织化学分析显示，我们所有的病例均对L-26/CD20cy和CD79a抗原染色，表达bcl-2、bcl-6和MUM-1蛋白，但对CD10/CALLA和CD138抗原均为阴性。在分子分析方面，所有PCLBCL-leg的淋巴瘤群体均存在Ig基因的高突变，除1例病例外，其余所有病例还存在BCL-6基因的突变。我们的结果表明，PCLBCL-leg在形态功能和分子特征方面与其他部位的大多数DLBCL相似。因此，在将腿部PCLBCL明确视为一个独特实体之前，谨慎行事似乎是合理的。
