breast cancer
DESCRIPTION
TRANSCRIPT
SEAN DAVENPORTBRIANNA CANTRELL
ASHLEY CLARKDANA OMARIEMILY SMITH
OLIVIA WOOLIVER
Breast Cancer
Breast Cancer
Breast cancer refers to a malignant tumor that has developed from cells in the breast
Cells of the lobules Milk producing glands
Ducts Passages that drain milk from the lobules to the nipple
Less commonly: Stromal tissues, which include the fatty and fibrous
connective tissues of the breast.
What are the symptoms?
Swelling of all or part of the breastSkin irritation or dimplingBreast painNipple pain or the nipple turning inwardRedness, scaliness, or thickening of the
nipple or breast skinNipple discharge other than breast milkLump in the underarm area
Overview of Vitamin D
Role in serum calcium homeostasis – acts to increase or decrease serum calcium levelsAlso aids in calcium homeostasis in
other areas such as bone, kidney, intestine, etc.
Helps to maintain/control normal cell growth, differentiation, and proliferation
Overview of Calcium
Calcium plays a regulatory role in cell proliferation, differentiation, and apoptosis
Experimental studies show that Calcium intake is related to: An inverse relationship with mammographic breast
density Decreased fat-induced epithelial hyperproliferation of
the mammary gland and chemically-induced mammary carcinogenesis in rodents
Reduced amount of breast cancer precursors in epidemiologic studies
Study 1: Intakes of Calcium and Vitamin D and Breast Cancer Risk in Women
Background Increasing Calcium and Vitamin D intake in female
mice led to regression in mammary tumors. Evaluation of Calcium and Vitamin D intake Subjects were divided into groups
10,578 Premenopausal women 20,909 Post menopausal women
45 years or older
Dietary Assessment
Food frequency questionnaireAverage use of food and beverages
past 12 monthsCalcium and Vitamin D intakes
included sources from both Diets and Supplements
Ascertainment of Breast Cancer Cases
Follow up questionnaires on whether breast cancer was diagnosed Every 6 months for first year Annually after first year
Medical records attained to confirm diagnosis/death
Average 10 year follow-up of incident invasive breast cancer 276 premenopausal women diagnosed 743 post menopausal women diagnosed
Influences
Examination of dietary factors Vitamin DPhosphorusFatLactose
Results
Relation to function: Premenopausal women
Higher intakes of total Calcium & Vitamin D were associated with lower risk of breast cancer
Postmenopausal women No association between calcium/Vitamin
D levels and risk of breast cancer Possible explanation: relationship between
Calcium, Vitamin D, and IGFs
Discussion
Calcium, Vitamin D, and IGFs:Suggestion that Calcium & Vitamin D
have anti-cancer effects on breast cancer cells expressing high levels of IGF-1 & IGF binding protein 3
Promote growth inhibitionIGF levels decline with age
Strengths Weaknesses
Large sample sizeProspective designLong durationHigh follow-up rates
Possible confoundNutrient intake only
assessed onceVitamin D intake
from sunlight exposure
Discussion
Study 2: Long-term dietary calcium intake and breast cancer risk in a prospective cohort of women
To examine the potential association between Calcium intake and breast cancer risk and whether this association varies by ER/PR status of the breast tumor
Subjects and Methods
Swedish Mammography CohortPopulation-based cohort of 61,433 women
cancer-free at baselineEnrollment: 1987-1990Two questionnaires:
Baseline 1997
Case ascertainment for ER/PR status Pathology labs, Clinical databases
Results
17.4 year follow up on average 4.81% developed invasive breast cancer
Of these cases: 62.4% ER+/PR+ 20.2% ER+/PR- 12.9% ER-/PR- 4.5% ER-/PR+
Adjustments made for: Dietary Vitamin D Conjugated Linoleic Acid intake
Results
Results
Highest Calcium Intake 34% less likely to develop ER-/PR- breast cancer
Overall Calcium Intake Decreased receptor-negative species of breast cancer However, association was not statistically significant
Strengths Weakness
Prospective and population based design
Large sample sizeDetailed info on dietInfo on hormone
receptor status
Dietary intake was self-administered FFQ
Confounding variables
Discussion
Conclusion
Nutrient Mechanisms: Calcium absorption is positively correlated with
vitamin D intake Vitamin D works inversely with estrogen receptors
(ERs) and progesterone receptors (PRs), and actually has its own receptors (VDRs) in mammary glands/tissue Apart from its role in aiding calcium absorption, the
receptors for vitamin D found here could indicate a bigger part in preventing cancer
This facet needs further research for conclusive evidence
Pros Cons
Easier to administer
Cheaper than conducting a Randomized Control Study (RCT)
Hard to identify controls
Blinding is difficult Recall &/or
volunteer bias
Cohort: designed to show incidence; best for predicting risk factors in research, based on exposure or no exposure
Questions