Breast Cancer

Breast Cancer

• Most common cancer in American women (excluding skin cancer) and second leading cause of cancer death in women after lung cancer.

• Incidence and deaths are decreasing due to reduced postmenopausal hormone therapy, earlier detection, and improved treatments. Largest group of cancer survivors.

Breast Cancer: Etiology and Risk Factors

• The exact cause is unknown, but risk increases with age, family history, hormonal exposure, lifestyle factors, and genetic mutations. Having multiple risk factors further increases the risk.

• About 5–10% of cases are hereditary, usually involving BRCA1 or BRCA2 mutations. Having a first-degree relative with breast cancer doubles the risk.

• BRCA mutations increase the risk of breast and ovarian cancer, so genetic counseling and testing are recommended for high-risk patients.

Breast Cancer: Risk Factors in Women

• The strongest risk factors are being female (99% of cases) and increasing age, especially after age 55.

• Hormonal risks include starting menstruation before age 12, menopause after age 55, never having children, having a first child after age 30, and taking estrogen/progesterone therapy.

• Other risks include obesity, physical inactivity, smoking, alcohol use, and radiation exposure.

Breast Cancer: Risk Factors in Men

• Risk increases with estrogen use, high estrogen levels, family history, radiation exposure, and BRCA mutations.

• Men with BRCA mutations should have yearly clinical breast exams starting at age 35 and report any breast changes. Routine screening mammograms are generally not recommended.

Breast Cancer: Pathophysiology

• Cancer usually develops in the ducts (ductal carcinoma) or lobules (lobular carcinoma). It may be in situ (confined to its original location) or invasive (spread into surrounding tissue).

• Common sites of metastasis include the bone, liver, lungs, and brain.

• Prognosis depends on tumor size, lymph node involvement, tumor differentiation, hormone receptor status (estrogen/progesterone), and HER2 status. More lymph nodes involved means a worse prognosis.

Types of Breast Cancer: Noninvasive

• Makes up about 20% of breast cancers and remains confined to the milk ducts or lobules without invading surrounding tissue. Also called carcinoma in situ.

• Ductal carcinoma in situ (DCIS) is usually found in one breast and can become invasive if untreated. Treatment may include lumpectomy, radiation, mastectomy, or hormone therapy (tamoxifen).

• Lobular carcinoma in situ (LCIS) is now considered a benign condition that increases breast cancer risk, rather than cancer itself. Surgery and radiation are not needed, but preventive hormone therapy may be used.

Types of Breast Cancer: Invasive Ductal Carcinoma

• The most common type of invasive breast cancer, accounting for about 80% of cases.

• Begins in the milk ducts and breaks through the duct walls into surrounding breast tissue, where it can spread to other parts of the body (metastasize).

Types of Breast Cancer: Invasive Lobular Carcinoma

• Accounts for 10–15% of invasive breast cancers and begins in the lobules (milk-producing glands). It can spread into surrounding tissue and metastasize to other parts of the body.

• Usually appears as a subtle thickening in the upper outer quadrant of the breast and is often difficult to detect on a mammogram.

Types of Breast Cancer: Inflammatory Breast Cancer

• A rare, aggressive, fast-growing cancer with a high risk of metastasis and poor prognosis. It accounts for about 1–3% of breast cancers.

• Cancer cells block the lymph channels in the breast skin, causing redness, warmth, thickening, and an orange-peel appearance (peau d’orange).

• Often mistaken for mastitis, but symptoms do not improve with antibiotics. A lump may not be present, and mammograms may not detect it.

Types of Breast Cancer: Paget Disease

• A rare cancer (1% of cases) that begins in the breast ducts and spreads to the nipple and areola. Most patients have underlying ductal carcinoma.

• Symptoms include itching, burning, bloody nipple discharge, skin erosion, and ulceration. Often mistaken for dermatitis or infection, delaying diagnosis.

• Treatment involves lumpectomy or mastectomy, sometimes followed by radiation. Prognosis is good when the cancer is confined to the nipple.

Types of Breast Cancer: Phyllodes Tumor

• A rare, fast-growing tumor that develops in the breast's connective tissue (stroma). Most are benign, but some are cancerous.

• Treatment usually involves surgical excision with wide margins. Axillary lymph node surgery is generally not needed.

Types of Breast Cancer: Triple-Negative Breast Cancer

• Tests negative for all three receptors: estrogen, progesterone, and HER2. More common in Black and Hispanic women, premenopausal women, and those with BRCA1 mutations.

• Typically more aggressive with a poorer prognosis. Does not respond to hormone therapy or HER2-targeted therapy, so chemotherapy is a major treatment option.

Breast Cancer: Clinical Manifestations

• Usually detected as a lump, thickening, or abnormal mammogram, most often in the upper outer quadrant of the breast. The lump is typically hard, irregular, poorly defined, nonmobile, and nontender.

• Other signs include unilateral nipple discharge (clear or bloody), nipple retraction, and skin changes such as dimpling, thickening (induration), and peau d’orange (orange-peel appearance caused by blocked lymph vessels).

Breast Cancer: Complications

• The main complication is recurrence, which can be local or regional (near the original tumor site or nearby lymph nodes) or distant (metastatic disease).

• Cancer spreads primarily through the lymphatic system, especially the axillary lymph nodes. Common sites of metastasis include the bone, lungs, brain, and liver.

Breast Cancer Diagnostic Studies: Axillary Lymph Node Analysis

• Examines the axillary lymph nodes to determine if cancer has spread. The more lymph nodes involved, the greater the risk of recurrence.

• Sentinel lymph node biopsy (SLNB) uses radioactive material and/or blue dye to locate the first lymph nodes that drain the tumor. Usually 1–4 nodes are removed, and if negative, no further axillary surgery is needed.

• Axillary lymph node dissection (ALND) may be needed if sentinel nodes are positive or cannot be identified. Usually 12–20 nodes are removed, making it more invasive than SLNB.

Breast Cancer Diagnostic Studies: Tumor Size

• Larger tumors generally have a poorer prognosis.

• Well-differentiated tumors resemble normal cells and are less aggressive, while poorly differentiated tumors appear abnormal and disorganized, making them more aggressive.

Breast Cancer Diagnostic Studies: Estrogen and Progesterone Receptor Status

• Hormone receptor testing (ER and PR) helps determine treatment options and prognosis for newly diagnosed or metastatic breast cancer and DCIS.

• Receptor-positive tumors are usually well differentiated, have a lower risk of recurrence, and typically respond to hormone therapy.

• Receptor-negative tumors are often poorly differentiated, more aggressive, have a higher risk of recurrence, and usually do not respond to hormone therapy.

Breast Cancer Diagnostic Studies: Genomic Assay

• HER2 testing is done on newly diagnosed or metastatic breast cancer. HER2 overexpression occurs in 10–20% of cases and is associated with aggressive tumor growth, increased recurrence, and poorer prognosis. It also helps guide treatment decisions.

• Gene expression testing, most commonly Oncotype DX (21-gene test), examines tumor genes to predict the risk of recurrence and potential benefit of chemotherapy or hormone therapy.

Breast Cancer Diagnostic Studies: Cell-Proliferative Indices

• Measure how quickly tumor cells are dividing and growing, particularly the number of cells in the S phase of the cell cycle.

• A high S-phase fraction indicates faster tumor growth, a greater risk of recurrence, and earlier cancer death.

Breast Cancer Diagnostic Studies: Fine Needle Aspiration

• Uses a thin, hollow needle to remove cells or fluid from a suspicious breast lump. Often used to determine whether a lump is a fluid-filled cyst or solid mass.

• Minimally invasive, but may not collect enough tissue for a definite diagnosis, requiring further biopsy.

Breast Cancer Diagnostic Studies: Core Needle Biopsy

• Uses a larger, hollow needle to remove small cylinders of breast tissue, usually with local anesthesia and imaging guidance.

• Often the preferred biopsy for suspected breast cancer because it collects more tissue than fine needle aspiration without requiring surgery.

Breast Cancer Diagnostic Studies: Vacuum-Assisted Biopsy

• Uses an image-guided probe with vacuum suction to remove multiple or larger tissue samples through a small incision.

• Allows multiple samples to be collected without repeatedly inserting the needle and causes minimal scarring.

Breast Cancer Diagnostic Studies: Excisional Biopsy

• A surgical procedure that removes the entire suspicious lump or abnormal area, sometimes along with a margin of surrounding healthy tissue.

• More invasive than needle biopsies and usually performed when needle biopsy results are inconclusive or do not match imaging findings.

Breast Cancer: Staging

• Uses the TNM system to determine cancer stage based on tumor size (T), lymph node involvement (N), and presence of metastasis (M).

• Stages range from 0 to IV. Stage 0 is noninvasive (in situ) with no lymph node involvement or metastasis, while Stage IV means the cancer has spread to distant parts of the body, regardless of tumor size or lymph node involvement.

• Staging also considers tumor grade, hormone receptor status (ER/PR), HER2 status, and genomic testing to better predict prognosis and guide treatment.

Breast Cancer Staging: Stage 0

• Noninvasive (carcinoma in situ) cancer that remains confined to its original location, with no lymph node involvement or metastasis.

Breast Cancer Staging: Stage I

• Early-stage invasive cancer, typically 2 cm or smaller, with no lymph node involvement or only tiny amounts of cancer in nearby lymph nodes (micrometastases).

• No distant metastasis.

Breast Cancer Staging: Stage II

• Cancer is generally larger (up to 5 cm or more) and/or has spread to 1–3 nearby lymph nodes.

• No distant metastasis.

Breast Cancer Staging: Stage III

• Locally advanced cancer that may extend into the chest wall or skin or involve multiple lymph nodes, sometimes 10 or more.

• No distant metastasis.

Breast Cancer Staging: Stage IV

• Cancer has metastasized to distant organs, most commonly the bones, lungs, liver, or brain.

• Can occur with any tumor size or amount of lymph node involvement.

Breast Cancer Treatments: Lumpectomy

• Also called breast-conserving surgery, it removes the tumor along with a margin of healthy tissue while preserving the rest of the breast.

• Usually followed by radiation therapy to reduce recurrence. It has the same overall survival rate as mastectomy when combined with radiation for appropriate patients.

• Common complications include breast swelling, soreness, skin changes, infection, and lymphedema, especially if axillary lymph nodes are removed.

Breast Cancer Treatments: Mastectomy

• Removes the entire breast. A simple mastectomy preserves the chest muscles, while a modified radical mastectomy also removes axillary lymph nodes but preserves the pectoralis major muscle.

• Breast reconstruction may be performed immediately or later using implants or the patient's own tissue. Some patients choose a breast prosthesis instead.

• Common complications include pain, infection, limited arm mobility, sensory changes, and lymphedema, especially when lymph nodes are removed.

Breast Cancer Treatments: Radiation Therapy

• Used after surgery to reduce local recurrence, prevent spread to nearby lymph nodes, or relieve pain from metastatic cancer.

• Can be given as external radiation or internal radiation (brachytherapy). Common side effects include fatigue, skin changes, and breast swelling.

Breast Cancer Treatments: External Radiation Therapy

• Delivers radiation from outside the body to the breast or nearby lymph nodes. Usually given 5 days per week for 3–4 weeks with newer shortened treatment schedules.

• May include an additional boost dose to the original tumor site after a lumpectomy. Treats localized cancer but does not prevent distant metastasis.

Breast Cancer Treatments: Brachytherapy

• Uses internal radiation placed directly into the cavity left after a lumpectomy, typically for certain patients with early-stage breast cancer.

• Delivers focused radiation through catheters or a balloon system, requiring fewer treatments. The radioactive source is removed after each treatment, so no radiation remains in the body.

Breast Cancer Treatments: Palliative Radiation Therapy

• Used to shrink tumors and relieve pain or other symptoms caused by advanced or metastatic breast cancer.

• Commonly targets cancer that has spread to the bones, brain, chest, or other tissues.

Breast Cancer Treatments: Drug Therapy

• Includes chemotherapy, hormone therapy, targeted therapy, and immunotherapy to reduce recurrence and improve survival.

• Neoadjuvant therapy is given before surgery to shrink tumors and make surgical removal easier. Adjuvant therapy is given after surgery to reduce the risk of recurrence.

Breast Cancer Treatments: Chemotherapy

• Uses cytotoxic drugs to destroy cancer cells. Multiple drugs are often combined to target different parts of the cell cycle, usually for 3–6 months.

• Common side effects include nausea, weight loss, anemia, hair loss, and cognitive changes ("chemo brain").

• Doxorubicin can cause cardiotoxicity and heart failure. Monitor for shortness of breath, edema, dysrhythmias, and decreased activity tolerance.

Breast Cancer Treatments: Hormone Therapy

• Used for ER-positive and/or PR-positive breast cancers to prevent estrogen from stimulating tumor growth.

• Works by blocking estrogen receptors or reducing estrogen production. Treatment depends on whether the patient is premenopausal or postmenopausal.

Breast Cancer Treatments: Tamoxifen

• Blocks estrogen receptors in breast tissue and is used for ER-positive breast cancer in both premenopausal and postmenopausal women.

• Common side effects include hot flashes, mood changes, and vaginal dryness. Serious risks include blood clots, stroke, and endometrial cancer.

• Teach patients to report abnormal vaginal bleeding, vision changes, leg swelling, or shortness of breath.

Breast Cancer Treatments: Aromatase Inhibitors

• Anastrozole, letrozole, and exemestane reduce estrogen production by blocking the aromatase enzyme.

• Primarily used for ER-positive breast cancer in postmenopausal women, since they do not stop ovarian estrogen production.

• Common side effects include joint and muscle pain, night sweats, osteoporosis, and increased fracture risk.

Breast Cancer Treatments: Targeted Therapy

• Uses drugs that target specific proteins or genetic mutations that help cancer cells grow. HER2 inhibitors, such as trastuzumab (Herceptin), block growth signals in HER2-positive breast cancer.

• Kinase inhibitors slow cancer cell division, while PARP inhibitors are used for certain breast cancers with BRCA mutations.

• Trastuzumab commonly causes flu-like symptoms, nausea, diarrhea, and infusion reactions. Its most serious risk is cardiotoxicity and heart failure, so cardiac function must be monitored.

Breast Cancer Treatments: Immunotherapy

• Uses immune checkpoint inhibitors to help the immune system recognize and attack cancer cells, especially in triple-negative breast cancer.

• Pembrolizumab (Keytruda) is given with chemotherapy before surgery for high-risk, early-stage triple-negative breast cancer, increasing the chance of a complete response, regardless of PD-L1 status. It may also be continued after surgery.

Nursing Management: Breast Cancer — Assessment

• Ask about breast lumps, pain, nipple discharge, breast changes, and menstrual history. Review family history, BRCA mutations, hormone use, and previous breast cancer.

• Assess any lump for size, location, shape, consistency, and mobility. Note nipple changes, skin dimpling, peau d’orange, and enlarged axillary or supraclavicular lymph nodes.

• Watch for possible metastasis, including bone pain, headaches, unexplained weight loss, shortness of breath, or jaundice.

Nursing Management: Breast Cancer — Diagnosis

• Common nursing problems include difficulty coping, deficient knowledge, and negative body image related to the diagnosis and potential treatment.

• After surgery, additional concerns may include acute pain, impaired mobility, and risk for infection or lymphedema.

Nursing Management: Breast Cancer — Planning

• Goals are for the patient to participate in treatment decisions, follow the treatment plan, and recognize and manage side effects.

• Encourage emotional support from family and the healthcare team, along with continued follow-up and cancer surveillance.

Nursing Management: Breast Cancer — Implementation

• Teach ways to reduce risk, including maintaining a healthy weight, exercising, limiting alcohol, avoiding smoking, and following screening recommendations.

• Before surgery, explain pain management, drain and dressing care, breathing exercises, mobility restrictions, and the recovery process.

• After surgery, encourage gradual arm and shoulder exercises to restore mobility. Give pain medication before exercises, teach drain care, and instruct patients to report fever, redness, unusual swelling, or new symptoms that may indicate recurrence.

Nursing Management: Breast Cancer — Evaluation

• The patient can identify ways to reduce swelling and improve arm mobility after surgery.

• Demonstrates effective coping, discusses feelings about body image changes, and identifies available support groups and counseling resources.

Nursing Management: Breast Cancer — Lymphedema

• Occurs when lymph fluid builds up in the arm, hand, or breast after lymph node removal or radiation. Symptoms include swelling, heaviness, numbness, tingling, and limited movement.

• Teach patients to avoid blood pressure readings, injections, and blood draws in the affected arm when possible. Protect the arm from injury and infection, avoid prolonged dependent positioning, and encourage gentle exercise.

• Treatment includes compression sleeves, manual lymph drainage, arm elevation, and exercises to improve fluid movement.

Nursing Management: Breast Cancer — Post-Breast Therapy Pain Syndrome

• Chronic pain that persists more than 3 months after treatment, usually caused by nerve injury from surgery, radiation, or chemotherapy.

• Symptoms include burning, aching, shooting pain, numbness, tingling, or itching in the chest, shoulder, or upper arm.

• Treatment may include NSAIDs, gabapentin, low-dose antidepressants, topical anesthetics, and physical therapy to manage pain and prevent shoulder stiffness.

Nursing Management: Breast Cancer — Phantom Breast Pain

• Occurs when a patient feels pain in a breast that has been removed following a mastectomy.

• Happens because the nervous system continues to produce pain sensations associated with the missing breast. Reassure the patient that these sensations are real and can occur after surgery.

Nursing Management: Breast Cancer — Psychosocial Support

• Diagnosis and treatment can cause anxiety, depression, fear of recurrence, and changes in body image, sexuality, and self-esteem.

• Screen all patients for emotional distress, encourage them to express their feelings, and provide a supportive environment without judgment.

• Include family or partners when appropriate and offer counseling, support groups, and resources to help patients cope with physical and emotional changes.

Nursing Management: Breast Cancer — Gerontological Considerations

• Risk increases with age, with more than half of breast cancers occurring in women age 55 or older.

• Screening and treatment decisions should be based on overall health rather than age alone, considering comorbidities, life expectancy, nutrition, mobility, cognitive function, and functional status.

• Healthy older women can receive the same treatments as younger women and have similar survival rates when matched by cancer stage.

Breast Cancer: Screening Guidelines

• Ages 40–44: May choose to begin annual mammograms.

• Ages 45–54: Should have annual mammograms.

• Ages 55+: May switch to mammograms every 2 years or continue annually. Screening should continue as long as the woman is in good health and expected to live at least 10 more years.

• High-risk women (BRCA mutations, strong family history, etc.) should generally have annual mammograms and breast MRIs starting at age 30.