国际预后指数（IPI）是治疗利妥昔单抗、环磷酰胺、多柔比星、长春新碱和泼尼松的弥漫性大B细胞淋巴瘤（DLBCL）患者最广泛使用的临床预测模型，但在老年患者中可能不太理想。我们旨在通过检查老年评估和淋巴瘤相关参考参数来开发和外部验证一个临床预测模型，以预测接受R-CHOP治疗的老年DLBCL患者的疗效。通过挪威癌症登记处，鉴定了共365名R-CHOP治疗的DLBCL患者，年龄≥70岁的基于人口的训练组。外部测试组包括193名人口基础的队列。候选预测者的数据从癌症登记处和临床记录中检索获取。使用Cox回归模型进行2年总生存率（OS）的模型选择。起居能力（ADL）、Charlson合并症指数（CCI）、年龄、性别、白蛋白、分期、ECOG和LDH被确定为独立预测因子，并组合成一种老年预后指数（GPI）。GPI评估显示良好的区别（校正C指数为0.752），并且识别了低、中、高危人群，其生存率显著不同（2年总生存率为94％、65％、25％）。在外部验证中，连续和分组的GPI显示出良好的区别（C指数为0.727，0.710），并且GPI组有明显不同的生存率（2年总生存率为95％、65％、44％）。连续和分组的GPI均比IPI、R-IPI和NCCN-IPI具有更好的区别（C指数为0.621，0.583，0.670）。我们已经开发并外部验证了用于治疗老年DLBCL患者的RCHOP的GPI，其表现优于IPI、R-IPI和NCCN-IPI。网络计算器可在https://wide.shinyapps.io/GPIcalculator/上使用。

International prognostic Index (IPI) is the most widely used clinical prediction model for diffuse large B-cell lymphoma (DLBCL) patients treated with rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP), but may be suboptimal in older patients. We aimed to develop and externally validate a clinical prediction model for older, R-CHOP treated DLBCL patients by examining geriatric assessment and lymphoma-related parameters in real-world cohorts. A population-based training set of 365 R-CHOP treated DLBCL patients ≥70 years was identified through the Cancer Registry of Norway. The external test set consisted of a population-based cohort of 193 patients. Data on candidate predictors was retrieved from the Cancer Registry and through review of clinical records. Cox regression models for 2-year overall survival (OS) were used for model selection. Activities of daily living (ADL), Charlson Comorbidity index (CCI), age, sex, albumin, stage, ECOG and LDH were identified as independent predictors and combined into a Geriatric prognostic index (GPI). The GPI demonstrated good discrimination (optimism-corrected C-index 0.752), and identified a low-, intermediate- and high-risk group with significantly different survival (2-year OS 94%, 65%, 25%). At external validation, the continuous and grouped GPI demonstrated good discrimination (C-index 0.727, 0.710) and the GPI groups had significantly different survival (2- year OS 95%, 65%, 44%). Both the continuous and grouped GPI showed better discrimination than IPI, R-IPI and NCCN-IPI (C-index 0.621, 0.583, 0.670). We have developed and externally validated the GPI for older DLBCL patients treated with RCHOP that outperformed IPI, R-IPI and NCCN-IPI. A web-based calculator is available at https://wide.shinyapps.io/GPIcalculator/.