Department of Surgery, University of Iowa Carver College of Medicine, Iowa City, Iowa.
Department of Surgery, University of Chicago, 5841 S Maryland Ave, Chicago, Illinois.
J Surg Res. 2021 Oct;266:104-112. doi: 10.1016/j.jss.2021.03.040. Epub 2021 May 11.
Young adults with metastatic colorectal cancer (mCRC) may have higher rates of deficient mismatch repair (dMMR) than older patients. This study sought to assess patterns of MMR-testing and survival among young adult mCRC patients in the National Cancer Database (NCDB), hypothesizing that dMMR correlates with worse survival than in MMR-proficient (pMMR) patients.
Stage-IV colorectal cancers were identified in NCDB (2010-2016). Demographic and clinical features were compared between younger (age ≤ 30) and older mCRC patients and tested for association with overall survival. Stage-IV disease without other recorded metastatic sites defined peritoneal metastasis (PM). Fisher-exact tests compared proportions and Cox models tested association with overall survival.
Of 124,587 stage-IV colorectal cancers, 1,123 (0.9%) were in young patients. Young patients were more likely to have mucinous histology, high-grade, rectal primaries, and isolated peritoneal metastases (P < 0.001). Younger patients more often had MMR-testing (29.1 versus 16.6%), with dMMR found at similar rates in young and older patients (21.7 versus 17.1% of those tested, P= 0.4). Despite higher rates of adverse prognostic features, younger patients had better survival (median 20.7 versus 14.8 months, P < 0.001). In MMR-tested patients, dMMR correlated with higher mortality risk compared to pMMR (median 16.6 months versus 25.5 months, P = 0.01). On multivariable analysis, grade and MMR-status remained independently associated with survival.
Median survival was worse with dMMR by 8.9 months compared to pMMR in young adults with mCRC. Despite higher rates of familial syndromes in young patients and recommendations for universal MMR-testing, over 70% of young mCRC patients had no MMR-status recorded.
转移性结直肠癌（mCRC）的年轻患者可能比老年患者有更高的错配修复缺陷（dMMR）率。本研究旨在评估国家癌症数据库（NCDB）中年轻成年 mCRC 患者的 MMR 检测和生存模式，假设 dMMR 与比 MMR 功能正常（pMMR）患者更差的生存相关。
在 NCDB 中确定 IV 期结直肠癌（2010-2016 年）。比较年轻（≤30 岁）和老年 mCRC 患者的人口统计学和临床特征，并测试与总生存的关联。无其他记录的转移部位的 IV 期疾病定义为腹膜转移（PM）。Fisher 精确检验比较比例，Cox 模型检验与总生存的关联。
在 124587 例 IV 期结直肠癌中，有 1123 例（0.9%）为年轻患者。年轻患者更有可能具有黏液组织学、高级别、直肠原发灶和孤立性腹膜转移（P < 0.001）。年轻患者更常进行 MMR 检测（29.1%比 16.6%），且年轻和老年患者的 dMMR 检出率相似（检测患者中分别为 21.7%和 17.1%，P=0.4）。尽管存在更高的不良预后特征，年轻患者的生存更好（中位 20.7 个月比 14.8 个月，P < 0.001）。在 MMR 检测患者中，dMMR 与 pMMR 相比，死亡率风险更高（中位 16.6 个月比 25.5 个月，P=0.01）。在多变量分析中，分级和 MMR 状态仍然与生存独立相关。
与 pMMR 相比，年轻成年 mCRC 患者的 dMMR 中位生存时间差 8.9 个月。尽管年轻患者中家族综合征的发生率较高且推荐进行普遍的 MMR 检测，但超过 70%的年轻 mCRC 患者没有记录 MMR 状态。
