Breast Cancer Lecture

-Cause is unknown

-No definitive prevention measure other than new anti-hormone therapy with the drug Tamoxifen

-Progressive disease

-Survival increases with early detection and treatment:

early stage 96%

late stage 20%

-In 1974, 1/15 women were diagnosed with breast cancer. In 2000, 1/8 woman will be diagnosed with breast cancer.

-Leading cause of cancer mortality in women ages 40 – 55

-Gender. 1/8 women, 1/100 men are diagnosed with breast cancer.

-Age. Risk increases with age.

-Personal family history.

-Nulliparous. Women who have never been pregnant have a greater risk factor.

-Onset and cessation of menses.

-Obesity

note: 75% of women with breast cancer have no identifiable risk factors.

-15% of breast cancers are familial; 45% are linked to the gene BRCA1, 45% are linked to BRCA2, and 10% are undefined.

-Involvement of multiple generations

-Involvement of multiple first degree relatives (Mom, Dad, Sister, Brother)

-Premenopausal breast cancer

-Bilateral breast cancer (cancer in both breasts)

-Presence of ovarian cancer

-A slightly increased incidence of cancer when all studies are considered

-Will increase the growth rate of an existing cancer

-Benefits (ie, prevention of osteoporosis) outweigh the risks

Breast cancer first develops in the lining cells (1 layer thick) of lobes and ducts.

The cancer may pull at the ligaments of the breast, causing noticeable indentations, dimples, and/or ridges in the breast.

Angiogenesis – blood vessel generation. Cancerous tumors grow and feed themselves by angiogenesis.

Sarcoma – tumor that lays in the supporting structures of the breast. Most commonly found in young women, 20’s and 30’s. Tumor feels soft, and is a round, large growth.

Mortality is due to the spread of breast cancer throughout the body rather than local growth; lethal dissemination can occur even with minimal primary growth.

-Size and spread of primary tumor

-Presence or absence of axillary nodal involvement (most important factor)

-Presence or absence of estrogen receptors in the tumor

-Most tumors under 1 cm do not have positive nodes

-50% of all patients with tumors of 2 cm have positive nodes

BSE (Breast Self Exam) – least likely to find cancer

Mammography – most likely to find cancer. Misses about 10% of breast cancers

Clinical Breast Examination

-Begin at age 40

-Detects 90% of all 1 cm breast cancers

-Compared with old mammography films to detect new suspicious growths

-Differentiates cysts from cancers. Cysts show up on ultrasounds as clear black spots; cancerous tumors will show up as a gray/white area.

-Finds cancers that may not show up on mammograms

-Women whose lesions are detected by mammography alone have better survival

-Routine screening mammography in women ages 50-60 results in 30% reduction in mortality

-Women ages 40-49 who undergo routine screening when followed more than 10 years show an increase in survival

-Risk of breast cancer for rest of life is 60%

-Does not tell you where cancer may occur next – ie, may be bilateral or in ducts

Options: 1) Observe

2) Bilateral simple mastectomy

Options: 1) Simple mastectomy

2) Excision and RT (radiotherapy – 6 weeks, 5 days a week)

3) Excision alone

Options: 1) Mastectomy

2) Mastectomy with reconstruction

3) Lumpectomy with axillary node dissection and RT – 60%

are treated this way

Options: 1) Modified radical hysterectomy

2) Induction chemotherapy, followed by mastectomy or lumpectomy and RT

-"Inflammatory histology"

-Survival rate 20%

-Induction chemotherapy followed by mastectomy and/or RT

Axillary node dissection is only indicated in extensive high grade ductal carcinoma in situ or invasive carcinoma

-Pacific Yew tree – the leaves from this tree are used in manufacturing the chemotherapy drug Taxol. It is one of the most efficient chemotherapy agents for breast and ovarian cancers.

-In order to spare any possible axillary nodes, doctors are injecting the breast with radioactive material and blue dye around the tumor site. They then trace the path to which lymph nodes are affected by the cancer and remove those only. This helps the lessen effects of lymphedema.