Kok Victor C, Tsai Horng-Jyh, Su Chi-Feng, Lee Chien-Kuan
*Division of Medical Oncology, Kuang Tien General Hospital Cancer Center, Shalu, Taichung, Taiwan; †Department of Biomedical Informatics, Asia University, Wufeng, Taichung, Taiwan; and Departments of ‡Obstetrics & Gynecology and §Pathology, Kuang Tien General Hospital, Shalu, Taichung, Taiwan.
Int J Gynecol Cancer. 2015 Jul;25(6):968-76. doi: 10.1097/IGC.0000000000000454.
Recent studies report a link between endometriosis and ovarian cancer (OC). Using a population-based cohort study to confirm the association between endometriosis and cancer is desirable. We thus examined the magnitude of the risks of OC, endometrial cancer (EC), breast cancer, colorectal cancer (CRC), and other cancers in women with newly diagnosed endometriosis or adenomyosis (internal endometriosis).
METHODS/MATERIALS: Women older than 20 years with claims data between 2003 and 2005 were identified from the Longitudinal Health Insurance Dataset containing 1 million individuals randomly sampled from the National Health Insurance Research Database. Those with preexisting malignancies, hysterectomy, or oophorectomy were excluded. The endometriosis cohort (n = 2266, including 768 cases of pure adenomyosis) and comparison cohort (n = 9064), formed by 1:4 matching, were followed up until incidence cancer, dropout, or December 31, 2008. Outcome measures included cancer incidence and adjusted hazard ratio by Cox model adjusted for age group, comorbidities, and endometriosis medication use.
With 9842 person-years of follow-up in endometriosis cohort and 36,274 person-years of follow-up in comparison cohort, there were increased risks of all cancers (adjusted hazard ratio, 1.8; 95% confidence interval, 1.4-2.4), OC (4.56, 1.72-12.11), and EC (4.05, 1.20-13.66). The ovarian endometriosis group was associated with increased risk of subsequent OC (4.37, 1.07-17.83). The adenomyosis group was strongly associated with both OC (5.50, 1.95-15.50) and EC (5.13, 1.36-19.40). Increased risk of subsequent CRC was observed in women with adenomyosis with coexistent endometriosis at other sites (13.04, 2.21-77.04). However, no statistically significant increased risk of breast or other cancers was observed.
Having limitations such as lacking of parity information which may affect the magnitude of risk estimates, this study demonstrates that ovarian endometriosis has a 4-fold increased risk of OC. Adenomyosis may associate with a 4- to 5-fold increased risk of OC and EC, and unexpectedly, a 13-fold increased risk of CRC.
近期研究报道了子宫内膜异位症与卵巢癌（OC）之间的联系。采用基于人群的队列研究来证实子宫内膜异位症与癌症之间的关联是很有必要的。因此，我们研究了新诊断为子宫内膜异位症或子宫腺肌病（内在性子宫内膜异位症）的女性患OC、子宫内膜癌（EC）、乳腺癌、结直肠癌（CRC）及其他癌症的风险程度。
方法/材料：从纵向健康保险数据集（该数据集包含从国民健康保险研究数据库中随机抽取的100万个人）中识别出2003年至2005年有理赔数据且年龄大于20岁的女性。排除有既往恶性肿瘤、子宫切除术或卵巢切除术的女性。通过1:4匹配形成子宫内膜异位症队列（n = 2266，包括768例单纯子宫腺肌病病例）和对照队列（n = 9064），随访至发生癌症、失访或2008年12月31日。结局指标包括癌症发病率以及通过Cox模型调整年龄组、合并症和子宫内膜异位症用药情况后的调整风险比。
子宫内膜异位症队列随访9842人年，对照队列随访36274人年，所有癌症（调整风险比，1.8；95%置信区间，1.4 - 2.4）、OC（4.56，1.72 - 12.11）和EC（4.05，1.20 - 13.66）的风险均增加。卵巢子宫内膜异位症组与后续OC风险增加相关（4.37，1.07 - 17.83）。子宫腺肌病组与OC（5.50，1.95 - 15.50）和EC（5.13，1.36 - 19.40）均密切相关。在其他部位同时存在子宫内膜异位症的子宫腺肌病女性中观察到后续CRC风险增加（13.04，2.21 - 77.04）。然而，未观察到乳腺癌或其他癌症风险有统计学意义的增加。
本研究存在诸如缺乏可能影响风险估计程度的生育信息等局限性，但表明卵巢子宫内膜异位症患OC的风险增加4倍。子宫腺肌病可能与OC和EC风险增加4至5倍相关，且出乎意料的是，与CRC风险增加13倍相关。
