目前尚不清楚饮食是否可能影响接受主动监测的男性前列腺癌等级重新分类的风险。旨在评估主动监测期间饮食质量和饮食炎症潜力与前列腺癌等级重新分类的关联。这项前瞻性队列研究包括诊断为等级组的男性(GG) 2005 年 1 月至 2017 年 2 月期间，有 1 名前列腺癌患者接受主动监测，并在主动监测登记时前瞻性地完成了一份关于其日常饮食模式的经过验证的食物频率调查问卷。数据分析时间为 2023 年 10 月 29 日至 2024 年 6 月 17 日。 1999-2000 年健康饮食指数 (HEI) 和能量调整后 HEI (E-HEI) 分数作为遵守美国人膳食指南和膳食指南的衡量标准使用自我报告的饮食数据计算炎症指数 (DII) 和能量调整 DII (E-DII) 分数作为膳食炎症潜力的指标。进行竞争风险回归来测试基线 HEI、E-HEI、DII 和在主动监测期间，E-DII 分数与等级重新分类为 GG2 或更高或 GG3 或更高（即极端等级重新分类）相关，调整已确定的主动监测预后因素和基线吸烟史。该研究包括 886 名男性（中位年龄）诊断时，66 岁 [IQR，61-69 岁]）。中位随访 6.5 年（IQR，4.0-9.1 年）后，187 例 (21%) 的等级重新分类为 GG2 或更高，其中 55 例 (6%) 的等级重新分类为极端。 3 年时等级重新分类的累积发生率为 7% (95% CI, 5%-9%)，5 年时为 15% (95% CI, 12%-17%)，33% (95% CI, 29 %-37%) 10 年；极端等级重新分类的 3 年时为 2%（95% CI，1%-4%），5 年时为 4%（95% CI，3%-5%），5 年时为 10%（95% CI，7%） -13%) 10 年。每 1 基线 HEI（次分布风险比 [SHR]，0.85；95% CI，0.73-0.98；P = .03）和 E-HEI（SHR，0.86；95% CI，0.74-1.00；P = .047）较高-SD 分数的增加与年级重新分类的风险显着降低相关。分数每增加 1-SD，基线 HEI（SHR，0.72；95% CI，0.57-0.93；P = .01）和 E-HEI（SHR，0.73；95% CI，0.57-0.94；P = .01）更高与极端等级重新分类的风险显着降低相关。基线 DII 和 E-DII 均与任一级别重新分类结果无关（例如，对于级别重新分类至 ≥GG2，DII 评分每增加 1-SD，SHR 为 1.08 [95% CI，0.93-1.26]，SHR 为 1.02 [95]。 % CI, 0.86-1.21] E-DII 评分每增加 1-SD）。研究结果表明，在接受主动监测的诊断为 GG1 前列腺癌的男性中，对美国饮食指南建议的较高遵守率可能与较低的分级风险相关重新分类，特别是 GG3 或更大的疾病，需要进行治愈性治疗。

It remains unclear whether diet may influence the risk of prostate cancer grade reclassification in men undergoing active surveillance.To assess the association of diet quality and dietary inflammatory potential with prostate cancer grade reclassification during active surveillance.This prospective cohort study included men diagnosed with grade group (GG) 1 prostate cancer from January 2005 to February 2017 who were undergoing active surveillance and at active surveillance enrollment prospectively completed a validated food frequency questionnaire regarding their usual dietary patterns. Data were analyzed from October 29, 2023, to June 17, 2024.The Healthy Eating Index 1999-2000 (HEI) and energy-adjusted HEI (E-HEI) scores as a measure of adherence to the Dietary Guidelines for Americans and the Dietary Inflammatory Index (DII) and energy-adjusted DII (E-DII) scores as metrics of dietary inflammatory potential were calculated using self-reported diet data.A competing risk regression was performed to test the baseline HEI, E-HEI, DII, and E-DII scores for an association with grade reclassification to GG2 or greater or GG3 or greater (ie, extreme grade reclassification) during active surveillance, adjusting for established active surveillance prognostic factors and smoking history at baseline.The study included 886 men (median age at diagnosis, 66 years [IQR, 61-69 years]). After median follow-up of 6.5 years (IQR, 4.0-9.1 years), 187 (21%) had grade reclassification to GG2 or greater, including 55 (6%) with extreme grade reclassification. The cumulative incidence of grade reclassification was 7% (95% CI, 5%-9%) at 3 years, 15% (95% CI, 12%-17%) at 5 years, and 33% (95% CI, 29%-37%) at 10 years; that of extreme grade reclassification was 2% (95% CI, 1%-4%) at 3 years, 4% (95% CI, 3%-5%) at 5 years, and 10% (95% CI, 7%-13%) at 10 years. Higher baseline HEI (subdistribution hazard ratio [SHR], 0.85; 95% CI, 0.73-0.98; P = .03) and E-HEI (SHR, 0.86; 95% CI, 0.74-1.00; P = .047) per 1-SD increase in score were associated with a significantly lower risk of grade reclassification. Higher baseline HEI (SHR, 0.72; 95% CI, 0.57-0.93; P = .01) and E-HEI (SHR, 0.73; 95% CI, 0.57-0.94; P = .01) per 1-SD increase in score were associated with a significantly lower risk of extreme grade reclassification. Neither the baseline DII nor E-DII was associated with either grade reclassification outcome (eg, for grade reclassification to ≥GG2, the SHR was 1.08 [95% CI, 0.93-1.26] per 1-SD increase in DII score and 1.02 [95% CI, 0.86-1.21] per 1-SD increase in E-DII score).The findings suggest that in men diagnosed with GG1 prostate cancer undergoing active surveillance, higher adherence to American dietary guideline recommendations may be associated with a lower risk of grade reclassification, particularly to GG3 or greater disease, which mandates curative treatment.