1Department of Cancer Control and Population Health, National Cancer Center Graduate School of Cancer Science and Policy, Goyang, Korea
2Department of Cancer Biomedical Science, National Cancer Center Graduate School of Cancer Science and Policy, Goyang, Korea
3Cancer Epidemiology Branch, National Cancer Center Research Institute, Goyang, Korea
4Department of Family Medicine and Center for Cancer Prevention and Detection, National Cancer Center Hospital, Goyang, Korea
Copyright © 2019 by the Korean Cancer Association
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Study | Source of participants (country) | Population (follow-up period) | Cancer type | Type of dietary omega-3 fatty acids | OR or RR or HR (95% CI) | Adjusted variable |
---|---|---|---|---|---|---|
Case-control study (n=6) | ||||||
Bidoli et al. (2002) [14] | Multicentric case-control study (Italy) | 1,031 Cases/2,411 controls (1991-1999) | Ovarian cancer | ALA | OR: 0.8 (0.6-1.0) | Age, study center, year of interview, education, parity, oral contraceptive use, and energy intake |
Tavani et al. (2003) [15] | Total omega-3 fatty acids | OR: 0.6 (0.4-0.7) | Age, study center, education, body mass index (BMI), energy intake, and parity | |||
Lucenteforte et al. (2008) [16] | Case-control study (Italy) | 454 Cases/908 controls (1992-2006) | Endometrial cancer | ALA | OR: 1.0 (0.7-1.6) | Age and study center, adjusted for year of interview, education, physical activity, BMI, history of diabetes, age at menarche, age at menopause, parity, oral contraceptives use, hormone replacement therapy use, and total energy intake |
Ibiebele et al. (2012) [17] | Australian ovarian cancer case-control study (Australia) | 1,366 Cases/1,414 controls (2002-2005) | Ovarian cancer | ALA | OR: 1.19 (0.93-1.52) | Age, education, BMI, smoking status, oral contraceptive use, parity, menopausal status, hormonal replacement therapy, total fat intake, total energy, and total ω-6 fatty acid intake |
EPA | OR: 0.87 (0.70-1.09) | |||||
DHA | OR: 0.92 (0.74-1.15) | |||||
DPA | OR: 1.06 (0.85-1.33) | |||||
Total omega-3 fatty acids | OR: 1.01 (0.80-1.28) | |||||
Arem et al. (2013) [22] | Population-based case-control study (United States) | 556 Cases/533 controls (2004-2008) | Endometrial cancer | ALA | OR: 0.91 (0.63-1.32) | Energy consumption, age, BMI, number of live births, menopausal status, oral contraceptive use, hypertension, smoking status, and race/ethnicity |
EPA | OR: 0.57 (0.39-0.84) | |||||
DHA | OR: 0.64 (0.44-0.94) | |||||
Total omega-3 fatty acids | OR: 0.75 (0.52-1.09) | |||||
Merritt et al. (2014) [19] | New England case-control study (United States) | 1,872 Cases/1,978 controls (1992-2008) | Ovarian cancer | Total omega-3 fatty acids | OR: 0.79 (0.66-0.96) | Age, study center, study phase, number of oral contraceptive use, family history of ovarian cancer, and history of tubal ligation |
Cohort study (n=4) | ||||||
Bertone et al. (2002) [13] | Nurses' Health Study cohort (United States) | 80,258 Nurses (1980-1996) | Ovarian cancer | ALA | RR: 1.00 (0.72-1.39) | Age, parity, age at menarche, oral contraceptive use and duration, menopausal status/postmenopausal hormone use, tubal ligation, and smoking status |
EPA | RR: 0.97 (0.64-1.48) | |||||
DHA | RR: 0.86 (0.55-1.33) | |||||
Brasky et al. (2014) [18] | VITamins and lifestyle cohort (United States) | 22,494 Women (2000-2010) | Endometrial cancer | ALA | HR: 0.85 (0.56-1.29) | Age, race, education, BMI, pack-years of smoking, physical activity, alcohol consumption, age at menarche, age at first birth, age at menopause, parity, years of combined hormone therapy, years of estrogen-only therapy, years of oral contraceptive use, oophoerectomy, family history of uterine cancer, family history of ovarian cancer, history of diabetes, and total energy |
EPA | HR: 1.73 (1.14-2.63) | |||||
DHA | HR: 1.66 (1.09-2.55) | |||||
EPA+DHA | HR: 1.79 (1.16-2.75) | |||||
Brasky et al. (2015) [20] | Women's Health Initiative observational study and clinical trial (United States) | 87,360 Postmenopausal women (1993-2010) | Endometrial cancer | ALA EPA DHA DPA EPA+DPA+DHA | HR: 0.96 (0.79-1.18) | Intervention assignment, US region, race, education, BMI, smoking, alcohol, physical activity, age at menarche, age at first birth, age at menopause, parity, duration of combined menopausal hormone therapy, duration of estrogen-alone hormone therapy, duration of oral contraceptive use, oophoerectomy status, family history of endometrial cancer, and history of diabetes |
HR: 0.81 (0.65-1.01) | ||||||
HR: 0.77 (0.63-0.95) | ||||||
HR: 0.85 (0.69-1.05) | ||||||
HR: 0.81 (0.66-1.00) | ||||||
Brasky et al. (2016) [21] | Black Women's Health Study (United States) | 47,602 African-American women (1995-2013) | Endometrial cancer | ALA | HR: 0.86 (0.56-1.33) | Age, time period, and total energy intake, U.S. region, education, BMI, physical activity, alcohol consumption, smoking, fruit consumption, vegetable consumption, age at menarche, age at menopause, parity, age at first birth, duration of combined hormone therapy, duration of estrogen-alone hormone therapy, duration of oral contraceptive use, and diabetes |
EPA | HR: 0.72 (0.47-1.10) | |||||
DHA | HR: 0.84 (0.54-1.30) | |||||
DPA | HR: 0.88 (0.57-1.36) | |||||
EPA+DPA+DHA | HR: 0.79 (0.51-1.24) |
Case-control study (n=6) |
Selection |
Comparability |
Expose |
Total | |||||
---|---|---|---|---|---|---|---|---|---|
Adequate definition of cases | Representati veness of cases | Selection of controls | Definition of controls | Comparability of cases and controls | Exposure ascertainment | Same ascertainment criteria for cases and controls | Non-response rate | ||
Bidoli et al. (2002) [14] | ☆ | ☆ | - | ☆ | ☆☆ | ☆ | ☆ | - | 7 |
Tavani et al. (2003) [15] | |||||||||
Lucenteforte et al. (2008) [16] | ☆ | ☆ | - | ☆ | ☆☆ | ☆ | ☆ | - | 7 |
Ibiebele et al. (2012) [17] | ☆ | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 8 |
Arem et al. (2013) [22] | ☆ | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 8 |
Merritt et al. (2014) [19] | ☆ | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 8 |
Cohort study (n=4) |
Selection |
Comparability |
Outcome |
Total | |||||
Representati veness of exposed cohort | Selection of non exposed cohort | Ascertainment of exposure | No present of outcome of interest at start of study | Comparability of cohorts | Assessment of outcome | Long follow-up enough for outcomes | Adequacy of follow-up of cohorts | ||
Bertone et al (2002) [13] | - | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 7 |
Brasky et al. (2014) [18] | ☆ | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 8 |
Brasky et al. (2015) [20] | ☆ | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 8 |
Brasky et al. (2016) [21] | - | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 7 |
Factor | No. of studies | Pooled OR/RR/HR (95% CI) | I2 (%) |
---|---|---|---|
Methodological quality | |||
Low (score of 7 stars) [15,16,21] | 3 | 0.76 (0.55-1.03) | 52.7 |
High (score of 8 stars) [17-20,22] | 5 | 0.93 (0.75-1.66) | 72.1 |
Type of omega-3 fatty acids | |||
EPA [13,17-22] | 6 | 0.88 (0.69-1.12) | 69.6 |
Endometrial cancer [18,20-22] | 4 | 0.86 (0.58-1.30) | 81.3 |
Ovarian cancer [13,17] | 2 | 0.89 (0.73-1.08) | 71.5 |
Case-control study [17,22] | 2 | 0.73 (0.48-1.09) | 71.4 |
Cohort study [13,18-20] | 4 | 0.98 (0.69-1.39) | 73.7 |
ALA [13,14,16-18,20-22] | 8 | 0.96 (0.86-1.06) | 39.8 |
Endometrial cancer [16,18,20-22] | 5 | 0.93 (0.81-1.08) | 0 |
Ovarian cancer [13,14,17] | 3 | 0.99 (0.77-1.26) | 58.6 |
Case-control study [14,16,22] | 4 | 0.97 (0.79-1.18) | 39.8 |
Cohort study [13,18,20,21] | 4 | 0.94 (0.81-1.09) | 0 |
DHA [13,17,18,20-22] | 6 | 0.89 (0.72-1.10) | 61.6 |
Endometrial cancer [18,20-22] | 4 | 0.89 (0.63-1.28) | 76.1 |
Ovarian cancer [13,17] | 2 | 0.91 (0.75-1.11) | 0 |
Case-control study [17,22] | 2 | 0.79 (0.56-1.13) | 61.9 |
Cohort study [13,18,20,21] | 4 | 0.96 (0.69-1.35) | 70.7 |
DPA [17,20,21] | 3 | 0.94 (0.81-1.08) | 3.5 |
Endometrial cancer [20,21] | 2 | 0.86 (0.71-1.03) | 0 |
Ovarian cancer [17] | 1 | 1.06 (0.85-1.33) | NA |
Case-control study [17] | 1 | 1.06 (0.85-1.33) | NA |
Cohort study [20,21] | 2 | 0.86 (0.71-1.03) | 0 |
Study | Source of participants (country) | Population (follow-up period) | Cancer type | Type of dietary omega-3 fatty acids | OR or RR or HR (95% CI) | Adjusted variable |
---|---|---|---|---|---|---|
Case-control study (n=6) | ||||||
Bidoli et al. (2002) [14] | Multicentric case-control study (Italy) | 1,031 Cases/2,411 controls (1991-1999) | Ovarian cancer | ALA | OR: 0.8 (0.6-1.0) | Age, study center, year of interview, education, parity, oral contraceptive use, and energy intake |
Tavani et al. (2003) [15] | Total omega-3 fatty acids | OR: 0.6 (0.4-0.7) | Age, study center, education, body mass index (BMI), energy intake, and parity | |||
Lucenteforte et al. (2008) [16] | Case-control study (Italy) | 454 Cases/908 controls (1992-2006) | Endometrial cancer | ALA | OR: 1.0 (0.7-1.6) | Age and study center, adjusted for year of interview, education, physical activity, BMI, history of diabetes, age at menarche, age at menopause, parity, oral contraceptives use, hormone replacement therapy use, and total energy intake |
Ibiebele et al. (2012) [17] | Australian ovarian cancer case-control study (Australia) | 1,366 Cases/1,414 controls (2002-2005) | Ovarian cancer | ALA | OR: 1.19 (0.93-1.52) | Age, education, BMI, smoking status, oral contraceptive use, parity, menopausal status, hormonal replacement therapy, total fat intake, total energy, and total ω-6 fatty acid intake |
EPA | OR: 0.87 (0.70-1.09) | |||||
DHA | OR: 0.92 (0.74-1.15) | |||||
DPA | OR: 1.06 (0.85-1.33) | |||||
Total omega-3 fatty acids | OR: 1.01 (0.80-1.28) | |||||
Arem et al. (2013) [22] | Population-based case-control study (United States) | 556 Cases/533 controls (2004-2008) | Endometrial cancer | ALA | OR: 0.91 (0.63-1.32) | Energy consumption, age, BMI, number of live births, menopausal status, oral contraceptive use, hypertension, smoking status, and race/ethnicity |
EPA | OR: 0.57 (0.39-0.84) | |||||
DHA | OR: 0.64 (0.44-0.94) | |||||
Total omega-3 fatty acids | OR: 0.75 (0.52-1.09) | |||||
Merritt et al. (2014) [19] | New England case-control study (United States) | 1,872 Cases/1,978 controls (1992-2008) | Ovarian cancer | Total omega-3 fatty acids | OR: 0.79 (0.66-0.96) | Age, study center, study phase, number of oral contraceptive use, family history of ovarian cancer, and history of tubal ligation |
Cohort study (n=4) | ||||||
Bertone et al. (2002) [13] | Nurses' Health Study cohort (United States) | 80,258 Nurses (1980-1996) | Ovarian cancer | ALA | RR: 1.00 (0.72-1.39) | Age, parity, age at menarche, oral contraceptive use and duration, menopausal status/postmenopausal hormone use, tubal ligation, and smoking status |
EPA | RR: 0.97 (0.64-1.48) | |||||
DHA | RR: 0.86 (0.55-1.33) | |||||
Brasky et al. (2014) [18] | VITamins and lifestyle cohort (United States) | 22,494 Women (2000-2010) | Endometrial cancer | ALA | HR: 0.85 (0.56-1.29) | Age, race, education, BMI, pack-years of smoking, physical activity, alcohol consumption, age at menarche, age at first birth, age at menopause, parity, years of combined hormone therapy, years of estrogen-only therapy, years of oral contraceptive use, oophoerectomy, family history of uterine cancer, family history of ovarian cancer, history of diabetes, and total energy |
EPA | HR: 1.73 (1.14-2.63) | |||||
DHA | HR: 1.66 (1.09-2.55) | |||||
EPA+DHA | HR: 1.79 (1.16-2.75) | |||||
Brasky et al. (2015) [20] | Women's Health Initiative observational study and clinical trial (United States) | 87,360 Postmenopausal women (1993-2010) | Endometrial cancer | ALA EPA DHA DPA EPA+DPA+DHA | HR: 0.96 (0.79-1.18) | Intervention assignment, US region, race, education, BMI, smoking, alcohol, physical activity, age at menarche, age at first birth, age at menopause, parity, duration of combined menopausal hormone therapy, duration of estrogen-alone hormone therapy, duration of oral contraceptive use, oophoerectomy status, family history of endometrial cancer, and history of diabetes |
HR: 0.81 (0.65-1.01) | ||||||
HR: 0.77 (0.63-0.95) | ||||||
HR: 0.85 (0.69-1.05) | ||||||
HR: 0.81 (0.66-1.00) | ||||||
Brasky et al. (2016) [21] | Black Women's Health Study (United States) | 47,602 African-American women (1995-2013) | Endometrial cancer | ALA | HR: 0.86 (0.56-1.33) | Age, time period, and total energy intake, U.S. region, education, BMI, physical activity, alcohol consumption, smoking, fruit consumption, vegetable consumption, age at menarche, age at menopause, parity, age at first birth, duration of combined hormone therapy, duration of estrogen-alone hormone therapy, duration of oral contraceptive use, and diabetes |
EPA | HR: 0.72 (0.47-1.10) | |||||
DHA | HR: 0.84 (0.54-1.30) | |||||
DPA | HR: 0.88 (0.57-1.36) | |||||
EPA+DPA+DHA | HR: 0.79 (0.51-1.24) |
Case-control study (n=6) | Selection |
Comparability |
Expose |
Total | |||||
---|---|---|---|---|---|---|---|---|---|
Adequate definition of cases | Representati veness of cases | Selection of controls | Definition of controls | Comparability of cases and controls | Exposure ascertainment | Same ascertainment criteria for cases and controls | Non-response rate | ||
Bidoli et al. (2002) [14] | ☆ | ☆ | - | ☆ | ☆☆ | ☆ | ☆ | - | 7 |
Tavani et al. (2003) [15] | |||||||||
Lucenteforte et al. (2008) [16] | ☆ | ☆ | - | ☆ | ☆☆ | ☆ | ☆ | - | 7 |
Ibiebele et al. (2012) [17] | ☆ | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 8 |
Arem et al. (2013) [22] | ☆ | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 8 |
Merritt et al. (2014) [19] | ☆ | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 8 |
Cohort study (n=4) | Selection |
Comparability |
Outcome |
Total | |||||
Representati veness of exposed cohort | Selection of non exposed cohort | Ascertainment of exposure | No present of outcome of interest at start of study | Comparability of cohorts | Assessment of outcome | Long follow-up enough for outcomes | Adequacy of follow-up of cohorts | ||
Bertone et al (2002) [13] | - | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 7 |
Brasky et al. (2014) [18] | ☆ | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 8 |
Brasky et al. (2015) [20] | ☆ | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 8 |
Brasky et al. (2016) [21] | - | ☆ | ☆ | ☆ | ☆☆ | ☆ | ☆ | - | 7 |
Factor | No. of studies | Pooled OR/RR/HR (95% CI) | I2 (%) |
---|---|---|---|
Methodological quality | |||
Low (score of 7 stars) [15,16,21] | 3 | 0.76 (0.55-1.03) | 52.7 |
High (score of 8 stars) [17-20,22] | 5 | 0.93 (0.75-1.66) | 72.1 |
Type of omega-3 fatty acids | |||
EPA [13,17-22] | 6 | 0.88 (0.69-1.12) | 69.6 |
Endometrial cancer [18,20-22] | 4 | 0.86 (0.58-1.30) | 81.3 |
Ovarian cancer [13,17] | 2 | 0.89 (0.73-1.08) | 71.5 |
Case-control study [17,22] | 2 | 0.73 (0.48-1.09) | 71.4 |
Cohort study [13,18-20] | 4 | 0.98 (0.69-1.39) | 73.7 |
ALA [13,14,16-18,20-22] | 8 | 0.96 (0.86-1.06) | 39.8 |
Endometrial cancer [16,18,20-22] | 5 | 0.93 (0.81-1.08) | 0 |
Ovarian cancer [13,14,17] | 3 | 0.99 (0.77-1.26) | 58.6 |
Case-control study [14,16,22] | 4 | 0.97 (0.79-1.18) | 39.8 |
Cohort study [13,18,20,21] | 4 | 0.94 (0.81-1.09) | 0 |
DHA [13,17,18,20-22] | 6 | 0.89 (0.72-1.10) | 61.6 |
Endometrial cancer [18,20-22] | 4 | 0.89 (0.63-1.28) | 76.1 |
Ovarian cancer [13,17] | 2 | 0.91 (0.75-1.11) | 0 |
Case-control study [17,22] | 2 | 0.79 (0.56-1.13) | 61.9 |
Cohort study [13,18,20,21] | 4 | 0.96 (0.69-1.35) | 70.7 |
DPA [17,20,21] | 3 | 0.94 (0.81-1.08) | 3.5 |
Endometrial cancer [20,21] | 2 | 0.86 (0.71-1.03) | 0 |
Ovarian cancer [17] | 1 | 1.06 (0.85-1.33) | NA |
Case-control study [17] | 1 | 1.06 (0.85-1.33) | NA |
Cohort study [20,21] | 2 | 0.86 (0.71-1.03) | 0 |
OR, odds ratio; RR, relative risk; HR, hazard ratio; CI, confidence interval; ALA, α-linolenic acid; EPA, eicosapentaenoic acid; DHA, docosahexaenoic acid; DPA, docosapentaenoic acid.
OR, odds ratio; RR, relative risk; HR, hazard ratio; CI, confidence interval; EPA, eicosapentaenoic acid; ALA, α-linolenic acid; DHA, docosahexaenoic acid; DPA, docosapentaenoic acid; NA, not applicable.