Department of Medical Oncology, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, China.
Department of Medical Oncology, Sichuan Cancer Hospital & Institute, Sichuan Cancer Center, Affiliated Cancer Hospital of University of Electronic Science and Technology of China, Chengdu, China.
Cancer Med. 2023 Dec;12(23):21188-21198. doi: 10.1002/cam4.6686. Epub 2023 Nov 23.
Primary breast diffuse large B-cell lymphoma (PB-DLBCL) is a rare subtype of extranodal DLBCL, and the standard treatment remains controversial. In this study, we aimed to define the optimal treatment management in the rituximab era.
A total of 5089 newly diagnosed DLBCL patients treated with rituximab-containing immunochemotherapy between 2008 and 2019 from the Chinese Southwest Oncology Group-affiliated institutes were identified, of whom 135 diagnosed with PB-DLBCL were eligible for this analysis.
PB-DLBCL accounted for 2.7% of all DLBCLs. With a median follow-up of 4.2 years, the 5-year overall survival and progression-free survival rates were 84.8% and 71.6%, respectively. Breast and central nervous system (CNS) relapses were the main cause of treatment failure. We observed that consolidative breast radiotherapy (RT) significantly decreased breast relapse risk (5-year risk, 2.9% vs. 20.1%, p = 0.007). The CNS relapse risk was lower for patients who received high-dose methotrexate (HD-MTX) than for patients who did not (5-year risk, 0% vs. 15.2%, p = 0.015). We further screened the genetic mutation profile of 20 patients from two institutes, and found that MYD88 (25%) and CD79B mutations (25%) frequently occur in PB-DLBCL. In addition, four patients with MYD88 and/or CD79B mutations experienced CNS relapse, while three patients with MYD88 and/or CD79B mutations who received HD-MTX did not experience CNS relapse.
Collectively, our results indicate combined modality therapy including rituximab-containing immunochemotherapy and consolidative breast RT is a promising approach for PB-DLBCL, while HD-MTX is useful for preventing CNS relapse.
原发性乳腺弥漫性大 B 细胞淋巴瘤（PB-DLBCL）是结外弥漫性大 B 细胞淋巴瘤的一种罕见亚型，其标准治疗仍存在争议。本研究旨在明确利妥昔单抗时代的最佳治疗管理策略。
共纳入 2008 年至 2019 年期间来自中国西南肿瘤协作组附属机构的 5089 例接受利妥昔单抗为基础的免疫化疗治疗的新发弥漫性大 B 细胞淋巴瘤患者，其中 135 例诊断为 PB-DLBCL 患者符合本研究分析标准。
PB-DLBCL 占所有 DLBCL 的 2.7%。中位随访时间为 4.2 年，5 年总生存率和无进展生存率分别为 84.8%和 71.6%。乳腺和中枢神经系统（CNS）复发是治疗失败的主要原因。我们观察到，巩固性乳腺放疗（RT）显著降低了乳腺复发风险（5 年风险分别为 2.9%和 20.1%，p=0.007）。接受大剂量甲氨蝶呤（HD-MTX）治疗的患者 CNS 复发风险低于未接受者（5 年风险分别为 0%和 15.2%，p=0.015）。我们进一步对来自两个机构的 20 例患者进行了基因突变谱筛查，发现 MYD88（25%）和 CD79B 突变（25%）在 PB-DLBCL 中频繁发生。此外，4 例 MYD88 和/或 CD79B 突变患者发生 CNS 复发，而 3 例 MYD88 和/或 CD79B 突变患者接受 HD-MTX 治疗后未发生 CNS 复发。
综上所述，我们的研究结果表明，包括利妥昔单抗为基础的免疫化疗和巩固性乳腺 RT 的联合治疗方法可能是 PB-DLBCL 的一种有前途的治疗策略，而 HD-MTX 对预防 CNS 复发有用。
