Table 1.
Characteristics of cohort and case-control studies of the association between endometriosis and endometrial cancer or breast cancer
| Study, publication year and country | Study type | follow up time | Average age of baseline (years) | Sample size of the study | Endometriosis assessment | Age at diagnosis of endometriosis (years) | Cancer ascertainment | Adjusted RR(95%CI) | Adjustments | The way of information collection | NOS score |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Kyung Jin Eoh, 2021, Korean [19] | cohort study | NA | endometriosis cohort:40.4 ± 8.4 control:44.0 ± 17.0 | 263,273 | ICD code | ≥20 | ICD code | endometrial cancer: 4.59 (3.56–5.91) breast cancer: 1.44 (1.31–1.58) | Adjusted for age, insurance type, and comorbidities (diabetes, hypertension, hyperlipidemia, chronic obstructive pulmonary disease, chronic kidney disease, liver cirrhosis, and heart) | database | 7 |
| Fanghua Shen, 2020, China [39] | case- control study | – | NA | 876 | medical records | all ages | medical records | endometrial cancer: 0.36 (0.094–1.381) | Adjusted by age at diagnosis and parity | database | 6 |
| Frida E. Lundberg, 2019, Sweden [32] | cohort study | control cohort: 23.4 yearsa infertile cohort: 25.8 yearsa | NA | 2,882,847 | ICD code | all ages | ICD code | endometrial cancer: 0.94 (0.76–1.17) breast cancer: 1.02 (0.96–1.07) | EC: Adjusted for age, calendar time, education level, country of birth, parity and age at first birth, salpingectomy and bilateral oophorectomy BC: Adjusted for age, calendar time, education level, country of birth, parity and age at first birth, salpingectomy, hysterectomy and bilateral oophorectomy | database | 6 |
| Hsing-Chi Hsu, 2019, China [37] | cohort study | NA | nurses cohort:34.0 ± 7.66 control:34.0 ± 7.74 | 178,870 | ICD code | > 20 | ICD code | breast cancer: 0.62 (0.22–1.78) | Adjust for study cohort, age, and comorbidities with significant crude HR (cradiovascular disease and diabetes mellitus) | database | 7 |
| Liisu Saavalainen, 2018, Finland [31] | cohort study | 16.8 yearsa | endometriosis cohort:36.4 ±? | 49,933 | surgery | 10–60 | ICD code | breast cancer: 0.99 (0.94–1.03) | – | database | 4 |
| Eric S. Surrey, 2018, American [21] | cohort study | NA | endometriosis cohort:36.5 ± 8.2 control:36.4 ± 8.4 | 134,805 | ICD code | 18–49 | ICD code | endometrial cancer: 2.4 (1.6–3.8) breast cancer: 1.4 (1.1–1.7) | Adjust for age, state, and insurance type. Models also controlled for 15 Charlson–Deyo comorbidities measured during year before index date | database | 8 |
| Carrie L Williams, 2018, UK [25] | cohort study | 8.8yearsa | endometriosis cohort:34.5 ± 4.8 | 225,786 | patient reported and clinic reported information | all ages | ICD code | endometrial cancer: 0.75 (0.35–1.43) breast cancer: 0.98 (0.86–1.12) | – | database | 4 |
| Chih-Ching Yeh, 2018. China [34] | cohort study | NA | NA | 120,582 | ICD code | all ages | ICD code | endometrial cancer: 1.89 (1.07–3.35) breast cancer:0.99 (0.80–1.23) | Adjusted for the birth year and geographicregion, occupation, urbanization, monthly income, comorbidity | database | 6 |
| Leslie V. Farland, 2016, American [35] | cohort study | 24 years | endometriosis cohort:35.6 ± 4.2 control:34.3 ± 4.7 | 16,325 | laparoscopy or laparotom | 25–42 | medical records | breast cancer: 0.96 (0.88–1.06) | Adjust for age, calendar time, family history of breast cancer, age at menarche, body mass index, body mass index at age 18 years, smoking, biopsy confirmed benign breast disease, alcohol intake, recent health seeking behavior, birth weight, parity +age at first birth, breastfeeding, oral contraceptive | questionaire | 7 |
| L Saraswat, 2018, UK [22] | cohort study | 29 years | endometriosis cohort:32.1 ± 7.3 general population cohort:32.1 ± 7.3 | 281,937 | laparoscopy or laparotom | all ages | ICD code | endometrial cancer: 1.14 (0.57–2.28) breast cancer: 1.28 (1.06–1.54) | Adjust for age, socio-economic status and duration of follow up | database | 6 |
| Elizabeth M. Poole, 2017, America [36] | cohort study | 18 years | endometriosis cohort:44.5 ± 4.5b control:44.5 ± 4.6b | 107,721 | self-report | all ages | medical records | endometrial cancer: 0.74 (0.39–1.42) | Adjusted for BMI, parity, duration of post-menopausal hormones (by type), age at menopause, age at menarche, menstrual irregularity, infertility history, and duration of oral contraceptive use | questionaire | 7 |
| Julie Brøchner Mogensen, 2016, Denmark [20] | cohort study | 642,403 person-years | NA | 45,790 | clinical diagnoses | 25–49 | ICD code | endometrial cancer: 2.13 (1.77–2.55) breast cancer: 1.05 (1.00–1.11) | _ | database | 6 |
| Hann-Chin Yu, 2015, China [33] | cohort study | 10 years | _ | 139,392 | ICD code | all ages | ICD code | endometrial cancer: 2.83 (1.49–5.35) | Adjusted HRs were adjusted for patients’ age, urbanization level, monthly income, geographic region, hypertension, hyperlipidemia, obesity, and diabetes mellitus | database | 8 |
| Victor C. Kok, 2015, China [29] | cohort study | endometriosis cohort:9842 patients-years control cohort:36274 person-years | _ | 11,330 | ICD code | > 20 | ICD code | endometrial cancer: 4.05 (1.20–13.66) breast cancer: 1.15 (0.61–2.15) | Adjusted for age group, diabetes mellitus, chronic kidney disease, liver cirrhosis, rheumatoid arthritis, and use of medroxyprogesterone acetate, norethindrone acetate, danazol, and GnRH agonist | database | 8 |
| Stefanie Burghaus, 2015, German [42] | case- control study | – | endometrial cancer cases:65.6 ± 10.5 controls:60.9 ± 9.3 | 1305 | self-report | all ages | histopathology reports | endometrial cancer: 2.63 (1.28–5.41) | Adjusted for age, BMI, oral contraceptive use, pregnancies | questionnaire | 6 |
| Shu-Chun Chuang, 2015, China [41] | case- control study | – | – | 24,420 | ICD code | all ages | ICD code | breast cancer: 1.44 (1.15–1.80) | Adjusted for occupation, screen tests (never, once, and twice or above), and average ambulatory visit per year | database | 6 |
| Louise A. Brinton, 2014, American [30] | cohort study | 30.0 yearsa | _ | 12,193 | self-report | all ages | self-report and medical records | breast cancer: 1.12 (0.93–1.35) | Adjusted for study site, calendar year of first infertility evaluation and gravidity at first clinic visit | database and questionnaire | 4 |
| Jaime L. Matta, 2013, American [23] | case- control study | – | breast cancer cases:56.3 ±? controls:52.1 ±? | 991 | self-report | all ages | histopathology reports | breast cancer: 0.5 (0.30–0.90) | Adjusted by age, BMI, family history of breast cancer, menopause, alcohol use, smoking, multivitamin use, marital status, and saturated fat consumption | questionnaire | 7 |
| Luisa Morales, 2013, Puerto Rico [24] | case- control study | – | breast cancer cases:56.4 ± 12.6 controls:52.3 ± 12.5 | 1126 | self-report | all ages | histopathology reports | breast cancer: 0.61 (0.30–1.00) | Adjusted by age, BMI, family history of breast cancer, menopause, number of children, alcohol use, smoking, vitamin use | questionnaire | 4 |
| Ingrid J. Rowlands, 2011, Australia [40] | case- control study | – | endometrial cancer cases:61.29 ± 9.5 controls:60.83 ± 9.8 | 2938 | self-report | all ages | histopathology reports | endometrial cancer: 1.47 (1.00–2.17) | Adjusted for age (in years), age at menarche (in years), parous (no, yes), duration of OC use (never, b 60 months; ≥60 months), HRT use (≥ 3 months,< 3 months), smoking (ever, never), BMI (kg/m2) | questionnaire | 6 |
| Hazel B. Nichols, 2011, American [38] | case- control study | – | breast cancer cases:66.2 ± 7.4 controls:65.0 ± 7.5 | 10,046 | self-report | all ages | medical records | breast cancer: 0.99 (0.80–1.21) | Adjusted for age, US state, age at menarche, duration of oral contraceptive use, parity, age at first birth, age at menopause, postmenopausal hormone use, body mass index, mammography screening, and family history of breast cancer | telephone interview | 7 |
NA Information not available, RR Relative risk, CI Confidence interval;-a medium follow-up time;-b at midpoint of follow-up