Breast lumps risk factors

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Shadan Mehraban, M.D.[2]

Risk factors of breast lumps are generally age (higher cancer risk while aging), past history of breast disease or biopsy, positive familial history in first-degree relatives, genetic mutations such as BRCA1 and BRCA2, endogenous hormonal exposure such as age at menarch, first pregnancy, menopause, breast feeding, and parity, exogenous hormonal exposure such as usage of contraceptive pills and hormonal replacement therapy, and lifestyle factors such as alcohol consumption, inactivity, obesity, and previous history of radiation exposure.

Risk factors leading to female breast cancer:^[1][2]

• Age: probability of breast cancer during the age groups is as follows:
  • Birth to 39 years – 1 in 202
  • 40 to 59 years – 1 in 26
  • 60 to 69 years – 1 in 28.
• Personal history of benign breast biopsy associated with relative risk of 1.7 and history of atypical hyperplasia on biopsy with relative risk of 3.7.
• Breast pathology: Proliferative disease (PD) with atypia has greater risk of developing to breast cancer in comparison of PD.
• Family history: Greater breast cancer risk in women with first-degree relatives with breast cancer under 50 years old.
• Genetic predisposition
  • High risk (associated with relative risk about 3.0 to 7.0)
    • BRCA1
    • BRCA2
  • Moderate risk
    • Homozygous ataxia-telangiectasia (ATM)
    • Somatic mutation in CHEK2
    • BRCA1 modifier gene: BRIP1
    • BRCA2 modifier gene: PALB2
  • Low risk
    • These alleles have not designated yet
• Endogenous hormone exposure and reproductive factors:
  • Early menarche: Under age of 13 years
  • Parity: Nulliparus is associated with increased risk of breast cancer
  • Age at first full term pregnancy: Younger age ( under 20 years considered as low risk and after 30 years old considered as high risk ) may decrease risk of breast cancer
  • Breast feeding > 16 months decreased risk of breast cancer
  • Testosterone: Increased relative risk to 2.86-3.28
  • Age at menopause: Older menopausal age (aged > 55 years ) associated with greater risk of breast cancer
• Exogenous hormone exposure
  • Long term exposure> 5 years: increases chances of breast cancer
  • Time of usage: nearly menopausal age associated with development to breast cancer
  • Part or current use of contraceptive pills: relative risk of 1.07 to 1.2
  • Current use of hormonal replacement therapy: relative risk of 1.2
• Lifestyle: These factors may increase risk of developing breast cancers.
  • Alcohol consumption: approximately 2 to 5 drinks per day, developed with relative risk 1.4
  • Recreational exercise: relative risk of 0.70
  • Obesity: BMI = 25-29.9 and BMI >30 have relative risk of 1.28
  • Previous history of radiation: at the age < 35 years old

Template:WikiDoc Sources

Template:WikiDoc Sources