Department of Population Science, American Cancer Society, Atlanta, Georgia.
Department of Surveillance & Health Equity Science, American Cancer Society, Atlanta, Georgia.
JAMA Netw Open. 2024 Sep 3;7(9):e2433132. doi: 10.1001/jamanetworkopen.2024.33132.
Little is known about the causes of second primary cancers among individuals with a history of cancer. Descriptive studies have suggested that lifestyle factors, including excess body weight, may be important.
To investigate whether excess body weight is associated with the risk of a second primary malignant neoplasm among cancer survivors.
DESIGN, SETTING, AND PARTICIPANTS: This cohort study of adults in 21 states in the US used data from the Cancer Prevention Study II Nutrition cohort, a large prospective study that invited participants to respond to a survey in 1992 and biennial surveys starting in 1997, and who were followed-up through 2017. Eligible participants included those who received a diagnosis of a first primary nonmetastatic invasive cancer between 1992 and 2015. Data analysis occurred from September 2023 to March 2024.
Body mass index (BMI), computed from self-reported height and weight at the time of the first primary cancer diagnosis (mean [SD] years to diagnosis, 1.7 [1.5] years).
Main outcomes included a second primary cancer or an obesity-related second cancer. Cancer diagnoses were reported on biennial surveys and verified through medical record abstraction or linkage with state cancer registries.
This cohort included 26 894 participants who received a diagnosis of a first nonmetastatic primary cancer (mean [SD] age at first cancer diagnosis, 72.2 [6.5] years; 15 920 male [59.2%]). At the time of first diagnosis, 11 497 participants (42.8%) had overweight and 4684 (17.2%) had obesity. During a median (IQR) follow-up time of 7.9 (3.4-13.6) years, 3749 (13.9%) participants received a diagnosis of a second primary cancer, of which 1243 (33.2%) were obesity-related second primary cancers. Compared with cancer survivors whose BMI was in the normal range (18.5 to <25), there was 15% increased risk of any second primary cancer for those who had overweight (25 to <30; adjusted hazard ratio [aHR], 1.15; 95% CI, 1.07-1.25) and a 34% increased risk for those who had obesity (BMI ≥30; aHR, 1.34; 95% CI, 1.21-1.48), with greater risk for obesity-related second primary cancers, including a 40% increased risk for those with overweight (aHR, 1.40; 95% CI, 1.22,-1.61) and a 78% increased risk for those with obesity (aHR, 1.78; 95% CI, 1.51-2.11).
In this cohort study of older survivors of nonmetastatic cancer, those who had overweight or obesity at the time of their first cancer diagnosis were at higher risk of developing a second cancer, especially an obesity-related second cancer. Given the high prevalence of overweight and obesity among cancer survivors, it is important to promote survivorship care guidelines recommending weight management and increase awareness of second cancers among physicians and cancer survivors.
对于有癌症病史的个体中第二原发癌的病因知之甚少。描述性研究表明，生活方式因素，包括超重，可能很重要。
调查超重是否与癌症幸存者中第二原发恶性肿瘤的风险相关。
设计、地点和参与者：这项在美国 21 个州进行的成年人队列研究使用了癌症预防研究 II 营养队列的数据，这是一项大型前瞻性研究，邀请参与者在 1992 年回答一项调查，并从 1997 年开始每两年进行一次调查，随访至 2017 年。合格的参与者包括在 1992 年至 2015 年期间被诊断出患有第一原发非转移性浸润性癌症的患者。数据分析于 2023 年 9 月至 2024 年 3 月进行。
体重指数（BMI），根据首次原发性癌症诊断时的自我报告身高和体重计算（从诊断到平均[SD]年，1.7[1.5]年）。
主要结果包括第二原发癌或与肥胖相关的第二原发癌。癌症诊断在每两年进行一次的调查中报告，并通过病历摘录或与州癌症登记处的链接进行验证。
该队列包括 26894 名接受第一例非转移性原发性癌症诊断的患者（首次癌症诊断时的平均[SD]年龄，72.2[6.5]岁；15920 名男性[59.2%]）。在首次诊断时，11497 名患者（42.8%）超重，4684 名患者（17.2%）肥胖。在中位数（IQR）随访时间为 7.9（3.4-13.6）年期间，3749 名患者（13.9%）被诊断出患有第二原发癌，其中 1243 名（33.2%）为与肥胖相关的第二原发癌。与 BMI 处于正常范围内（18.5 至<25）的癌症幸存者相比，超重（25 至<30；调整后的危险比[aHR]，1.15；95%CI，1.07-1.25）和肥胖（BMI≥30；aHR，1.34；95%CI，1.21-1.48）的患者发生任何第二原发癌的风险增加 15%，与肥胖相关的第二原发癌的风险增加 34%，包括超重患者的风险增加 40%（aHR，1.40；95%CI，1.22-1.61）和肥胖患者的风险增加 78%（aHR，1.78；95%CI，1.51-2.11）。
在这项对非转移性癌症老年幸存者的队列研究中，首次癌症诊断时超重或肥胖的患者发生第二癌症的风险更高，特别是与肥胖相关的第二癌症。鉴于癌症幸存者中超重和肥胖的高患病率，重要的是要促进生存护理指南，建议进行体重管理，并提高医生和癌症幸存者对第二癌症的认识。
