Studies evaluating Positron Emission Tomography scan after 2 cycles of chemotherapy (PET2) in newly diagnosed diffuse large B cell lymphoma (DLBCL) are heterogeneous in patient characteristics, treatments and have conflicting results. Here we report association of PET2 with outcomes in two large independent prospective cohorts of newly diagnosed DLBCL pts treated with two RCHOP-based regimens. The discovery cohort consisted of pts enrolled in single arm phase 2 MC078E study of lenalidomide with RCHOP (R2CHOP). The validation cohort consisted of RCHOP-treated pts from the Molecular Epidemiology Resource (MER) cohort. Pts who received 3-6 cycles of therapy and had PET2 were included in the study. Patients who progressed on PET2 were excluded. Revised response criteria 2007 were used to define PET2 response PET2 positive (PET2 + ) pts had inferior EFS [24-month EFS 45.5% vs 87.9%, HR 4.0, CI₉₅ (2.1–7.9), p < 0.0001) with a trend towards lower OS [24-months OS 77% vs 94.8%, HR 2.0, CI₉₅ (0.9–4.8), P = 0.1] than PET2 negative (PET2−) pts in MC078E cohort. PET2 + pts had an inferior EFS (24 month EFS 48.7% vs 81.6%, HR 2.9, CI₉₅ 2.0–4.2, p < 0.0001) and OS (24-month OS 68.6% vs 88.1%, HR 2.3, CI₉₅: 1.5–3.5, p < 0.0001) in the MER cohort. These results were consistent regardless of age, sex and in the subgroup of advanced stage and high-risk international prognostic index (IPI). For MER, PET2 + pts also had higher odds of positive end of treatment PET (OR: 17.3 (CI₉₅ 7.9–37.7), p < 0.001). PET2 is an early predictor DLBCL pts at high risk of progression and death in two independent prospective cohorts. PET2-guided risk-adapted strategies may improve outcomes, and should be explored in clinical trials.

在新诊断的弥漫性大 B 细胞淋巴瘤 (DLBCL) 中评估 2 个化疗周期 (PET2) 后正电子发射断层扫描的研究在患者特征、治疗方面存在异质性，并且结果相互矛盾。在这里，我们报告了 PET2 与接受两种基于 RCHOP 的方案治疗的新诊断 DLBCL 患者的两个大型独立前瞻性队列的结果的关联。发现队列由参加来那度胺联合 RCHOP (R2CHOP) 单臂 2 期 MC078E 研究的患者组成。验证队列由来自分子流行病学资源 (MER) 队列的 RCHOP 治疗患者组成。接受 3-6 个周期治疗并具有 PE​​T2 的患者被纳入研究。PET2 进展的患者被排除在外。₉₅ (2.1–7.9)，p  < 0.0001) 与 PET2 阴性 (PET2−) 相比，OS 有降低趋势 [24 个月 OS 77% vs 94.8%，HR 2.0，CI ₉₅ (0.9–4.8)，P  = 0.1] MC078E 队列中的 pts。PET2 + 患者的 EFS（24 个月 EFS 48.7% 对 81.6%，HR 2.9，CI ₉₅ 2.0–4.2，p  < 0.0001）和 OS（24 个月 OS 68.6% 对 88.1%，HR 2.3，CI ₉₅：1.5 ）较差–3.5，p  < 0.0001) 在 MER 队列中。无论年龄、性别以及晚期亚组和高风险国际预后指数 (IPI)，这些结果都是一致的。对于 MER，PET2 + pts 也有更高的治疗结束 PET 阳性几率（OR：17.3 (CI ₉₅ 7.9–37.7)，p < 0.001)。PET2 是两个独立前瞻性队列中进展和死亡高风险的 DLBCL 患者的早期预测因子。PET2 指导的风险适应策略可能会改善结果，应在临床试验中进行探索。