Family history of cancer and the risk of cancer: a network of case–control studies

OBJECTIVE: Selecting controls is one of the most difficult tasks in the design of case-control studies. Hospital controls may be inadequate and random controls drawn from the base population may be unavailable. The aim was to assess the use of hospital visitors as controls in a case-control study on the association of organochlorinated compounds and other risk factors for breast cancer conducted in the main hospital of the "Instituto Nacional de Câncer" -- INCA (National Cancer Institute) in Rio de Janeiro (Brazil). METHODS: The study included 177 incident cases and 377 controls recruited among female visitors. Three different models of control group composition were compared: Model 1, with all selected visitors; Model 2, excluding women visiting relatives with breast cancer; and Model 3, excluding all women visiting relatives with any type of cancer. Odds ratios (OR) and 95% confidence intervals were calculated to test the associations. RESULTS: Age-adjusted OR for breast cancer associated with risk factors other than family history of cancer, except smoking and breast size, were similar in the three models. Regarding family history of all cancers, except for breast cancer, there was a decreased risk in Models 1 and 2, while in Model 3 there was an increased risk, but not statistically significant. Family history of breast cancer was a risk factor in Models 2 and 3, but no association was found in Model 1. In multivariate analysis a significant risk of breast cancer was found when there was a family history of breast cancer in Models 2 and 3 but not in Model 1. CONCLUSIONS: These results indicate that while investigating risk factors unrelated to family history of cancer, the use of hospital visitors as controls may be a valid and feasible alternative.

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Family history of cancer in first degree relatives and risk of cancer of unknown primary

European Journal of Cancer Care ◽

10.1111/ecc.13485 ◽

2021 ◽

Author(s):

Alexander L. R. Grewcock ◽

Karlijn E. P. E. Hermans ◽

Matty P. Weijenberg ◽

Piet A. Brandt ◽

Caroline Loef ◽

...

Keyword(s):

Family History ◽

Cancer Of Unknown Primary ◽

Unknown Primary ◽

Family History Of Cancer ◽

First Degree Relatives ◽

History Of ◽

Risk Of Cancer ◽

History Of Cancer

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Relation of Family History of Cancer and Environmental Factors to the Risk of Colorectal Cancer: A Case-control Study

Japanese Journal of Clinical Oncology ◽

10.1093/oxfordjournals.jjco.a039777 ◽

1995 ◽

Cited By ~ 1

Keyword(s):

Colorectal Cancer ◽

Family History ◽

Environmental Factors ◽

Case Control Study ◽

Case Control ◽

Family History Of Cancer ◽

History Of ◽

Control Study ◽

History Of Cancer

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Mortality and Risk of Cancer After Prophylactic Bilateral Oophorectomy in Women With a Family History of Cancer

JNCI Cancer Spectrum ◽

10.1093/jncics/pky034 ◽

2018 ◽

Vol 2 (3) ◽

Cited By ~ 1

Author(s):

Julie Abildgaard ◽

Magnus Glindvad Ahlström ◽

Gedske Daugaard ◽

Dorte Lisbet Nielsen ◽

Anette Tønnes Pedersen ◽

...

Keyword(s):

Breast Cancer ◽

Family History ◽

Rate Ratio ◽

Bilateral Oophorectomy ◽

Family History Of Cancer ◽

Increased Risk ◽

History Of ◽

Risk Of Cancer ◽

The Impact ◽

History Of Cancer

Abstract Background Current international guidelines recommend systemic hormone therapy (HT) to oophorectomized women until the age of natural menopause. Despite an inherited predisposition to estrogen-dependent malignancies, the guidelines also apply to women oophorectomized because of a family history of cancer. The objective of this study was to investigate the impact of HT on mortality and risk of cancer in women oophorectomized because of a family history of cancer. Methods A nationwide, population-based cohort was used to study women oophorectomized because of a family history of cancer (n = 2002). Comparison cohorts included women from the background population individually matched on age (n = 18 018). Oophorectomized women were subdivided into three groups: oophorectomized at 1) age 45 years or younger not using HT, 2) age 45 years or younger using HT, 3) older than age 45 years, and their respective population comparison cohorts. Results Women oophorectomized at age 45 years or younger using HT had increased overall mortality (mortality rate ratio [MRR] = 3.45, 95% confidence interval [CI] = 1.53 to 7.79), mortality because of cancer (MRR = 5.67, 95% CI = 1.86 to 17.34), and risk of overall cancer (incidence rate ratio [IRR] = 3.68, 95% CI = 1.93 − 6.98), primarily reflected in an increased risk of breast cancer (IRR = 4.88, 95% CI = 2.19 − 10.68). Women oophorectomized at age 45 years or younger not using HT and women oophorectomized at older than age 45 years did not have increased mortality, mortality because of cancer, or risk of overall cancer, but they had increased risk of breast cancer (IRR = 2.64, 95% CI = 1.14 to 6.13, and IRR = 1.72, 95% CI = 1.14 to 2.59, respectively). Conclusions Use of HT in women oophorectomized at age 45 years or younger with a family history of cancer is associated with increased mortality and risk of overall cancer and breast cancer. Our study warrants further investigation to establish the impact of HT on mortality and cancer risk in oophorectomized women with a family history of cancer.

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