Incidence of Disease:
•most common cancer among women in the US (excluding skin)
•second leading cause of cancer deaths in women⁵
•women in rural areas have lower breast cancer rates than do women in urban areas
•breast cancer is much more common in Western countries than Asian countries
•majority of breast cancer cases are diagnosed in women age 55 and older²
•1% of breast cancers occur in men⁷

Risk & Causative Factors:
•gender is the biggest risk because breast cancer occurs mostly in women
•age - the risk of breast cancer increases with age
•genetics - family history of breast cancer
•hormones - age of menarche, first pregnancy, menopause, use of oral contraceptives
•diet - high dietary fat intake
•lifestyle - overweight or obese
•benign breast disease
•environmental causes - radiation treatment to the upper body before 30 years of age⁹

Signs & Symptoms:
Breast cancer is often 1st detected as an abnormality on a mammogram before it is felt by the patient or health care provider. Mammographic features suggestive of malignancy include asymmetry, microcalcifications, a mass or architectural distortion. Breast ultrasound guided biopsy and or MR are the next studies in the workup. Only 5% of patients with a malignant mass present with breast pain. Other symptons include immobility, skin changes (thickening, swelling, redness) or nipple abnormalities (ulceration, retraction, spontaneous discharge).¹⁰
Diagnostic Procedures:
​Workup to include:
•physical examination with special attention given to locoregional extent of tumor and checking potiential sites of spread
•lab studies include a complete CBC, serum chemistry profile and full liver function tests
•if liver function values are abnormal, CT of the abdomen
•if anemia, leukopenia or thrombocytopenia is present, bone marrow biopsy is necessary
•imaging to include chest x-ray, bone scans, CT of chest and abdomen¹

"Infiltrating ductal carcinoma is the most common histologic type of breast malignancy, accounting for 70% of all breast cancers. Infiltrating lobular carcinoma is the next most common type, comprising about 5% to 10% of breast cancers." "There are several other relatively rare types of infiltrating breast cancer, such as mucinous or colloid, tubular, and papillary carcinoma. These lesions have distinct histologic characteristics and tend to yield a more favorable prognosis."⁸
Lymph Node Drainage:
A network of lymphatics lies over the entire surface of the chest, neck and abdomen and become dense under the areola. See image below.²

Lymphatic drainage moves superiorly and laterally towards the axillary lymph nodes. See image below of axillary lymph node levels.²

Metastatic Spread:
Lymphatic spread is most common, but breast cancer can also spread by direct invasion and by hematogenous spread.²
Lymphatic spread frequently occurs for T3 and T4 lesions to the axillary, internal mammary or supraclavicular lymph nodes. Direct extension can occur to the ribs, intercostal muscles, or skin. Hematogenous spread can occur to bone, lung, or pleura.¹
"Histologic tumor grade (sometimes called the Bloom-Richardson grade, Scarff-Bloom-Richardson grade, or Elston-Ellis grade) is based on the arrangement of the cells in relation to each other: whether they from tubules; how closely they resemble normal breast cells (nuclear grade); and how many of the cancer cells are in the process of dividing (mitotic count). This system of grading is used for invasive cancers but not for in situ cancers.
-Grade 1 (well differentiated) cancers have relatively normal-looking cells that do not appear to be growing rapidly and are arranged in small tubules.
-Grade 2 (moderately differentiated) cancers have features between grades 1 and 3.
-Grade 3 (poorly differentiated) cancers, the highest grade, lack normal features and tend to grow and spread more aggressively."⁴

AJCC/TNM (Please see table below)³

Radiation Side Effects:
Radiation sequelae are related to irradiated volume, total dose, and concurrent chemotherapy. After definitive irradiation for advanced breast carcinoma at M.D. Anderson, 20% developed severe cubcutaneous fibrosis; 5% to 10% had rib fractures and symptomatic pneumonitis, and a lower percentage had soft tissue and skin necrosis and ulceration.¹
The overall 5-year survival rate regardless of disease status is 85%. The 5-year survival decreases to 77% if evidence exists of regional spread. If there is metastasis present at the time of diagnosis the 5-year survival rate decreases to 21%.⁸ Survival rates correlate with early detection, tumor characteristics, treatment approach, and the patients condition. The 10-year survival rate is 75.7% and the 15-year survival rate is 57.7%. Patients may relapse up to 20 years or more after treatment. ⁸ 5-year survival rate for patients with lesions less than .5cm is 99%, and .5cm larger is 82%. With regional lymph node metastasis, 4.5cm tumors have a 70% incidence rate of nodal involvement, whereas 1.5cm tumors have a 38% incidence rate.⁸ Location of primary tumor does not directly affect prognosis.⁸
General Management
  • Because of a compelling need for systemic therapy, multiagent chemotherapy plays a primary role in the treatment of these patients.
  • Surgery should be performed on all patients with technically resectable disease. Borderline resectable and unresectable locally advanced breast cancers have been treated with irradiation alone.
  • Neoadjuvant chemotherapy before surgical resection and irradiation plays a prominent role.

Radiation Therapy Techniques
  • Patients with technically inoperable tumors should be irradiatied to the breast, supraclavicular nodes, and axillary nodes.
  • Treatment of the ipsilateral internal mammary lymph nodes may be indicated if medial chestwall/breast disease is present or if there is clinical or radiaographic involvement of the internal mammary node chain.
  • The breast is treated with photon through tangential fields with borders similar to those used in early breast cancer, ensuring that all potential tumor-bearing tissues are adequately covered.
  • Irradiation of the chest wall after mastectomy can be accomplished with tangential photos fields (as in the intact breast) or with appositional eletron beams.
  • Bolus is necessary over the entire field for part of the treatmetn, and should be added to the scar along for an additional part of the treatment.
  • Several electron-beam techniques can be used as an alternative to tangential photon treatment; the simplest is a single appositional field using 6 to 12 MeV electrons. CT scans assis in determining the thickness of the chest wall to select the optimal electron beam energy. Bolus should be used for part of the treatment to increase the surface dose beyond the 80% to 90% typically given with these beams, and to minimize the lung dose.
  • Anatomic landmarks defining the field borders for treatment of breast/chestwall tangentials, supraclavicular nodes, internal mammary nodes, and axilla are similar to those used to treat early breast cancer.
  • Total dose to the entire breast or chest wall is 50 Gy in 1.8 to 2.0 daily fractions.
  • If surgery is not feasible, the breast should be given an additional 10 to 25 Gy with external irradiaiton. This should be performed with shrinking fields to a dose of 75 to 80 Gy. The boost dose is determined by the volume of residual disease.
  • In patients with close or positive margins, a boost of 10 to 15 Gy is given to a reduced volume.
  • Internal mammary nodes, supraclavicular fossa nodes, and axillary nodeal areas should receive 45 to 50 Gy if no macroscopic tumor is present.
  • Any gross nodal disease should be boosted with an additional 10 to 15 Gy using a reduced appositional electron beam field.
  • In general, postmastectomy irradiation is recommended for lesions larger than 5 cm in diameter; any skin, fascial, or skeletal muscle involvement; poorly differentiated tumors; positive or close surgival margins; lymphatic permeation; matted lyumph nodes; two or more positive axillary lymph nodes; or gross extracapsular tumor extension.
  • Adjuvant irradiation can be effectively given before, concurrent with, or after chemotherapy.¹
The doses to the following organs should be limited:
Lung -- 1/3 of the volume is 45 Gy; 2/3 is 30 Gy; total is 17.5 Gy
Heart (if left sided breast cancer) -- 1/3 is 60 Gy; 2/3 is 45 Gy; total is 40 Gy¹

Planning Photos:
DRRs showing the different fields used in a mono-isocentric 4-field treatment for a Stage IIIA (T3, pN2a, M0) left breast cancer diagnosis.⁶
Supraclavicular Field

Posterior Axillary Boost Field

Medial Tangent Field

Lateral Tangent Field

Examples of the isodose distribution of a 4-field plan and a Rapid Arc plan, respectively, for a Stage IIIA (T3, pN2a, M0) left breast cancer diagnosis (patient had a mastectomy with expanders placed prior to treatment).⁶


1. Chao KS, Perez CA, Brady LW. Radiation Oncology - Management Decisions. 2nd ed. Philadelphia, PA: Lippincott, Williams & Wilkins; 2002: 367-375.
Lenards, N. Clinical Oncology for Medical Dosimetrists: Breast: Stage Tis, T1, and T2 Tumors. Course content - Slides 4, 5, 7. December 2009.
3. Google Images. http://imaging.cmpmedica.com/cancernetwork/cmhb11/11_8_Table7.gif. Accessed January 18, 2010.

4. American Cancer Society. How is Breast Cancer Diagnosed? http://www.cancer.org/docroot/CRI/content/CRI_2_4_3X_How_is_breast_cancer_diagnosed_5.asp . Accessed January 18, 2010.
5. Lenards, N. Clinical Oncology for Medical Dosimetrists: Breast: Locally Advanced (T3 and T4), Inflammatory, and Recurrent Tumors. Course content - Slide 3. December 2009.
6. Digitally Reconstructed Radiographs courtesy of Bridget Keehan, RT(T). The Cancer Team at Bellin Health.
7. 6. eMedicineHealth. Breast Cancer. http://www.emedicinehealth.com/breast_cancer/article_em.htm. Accessed January 19, 2010.
8. Washington CM, Leaver D, eds. Principles and Practice of Radiation Therapy, 2nd ed: 844-847. Philadelphia, PA: Mosby Inc, 2004.
9. Chen A, Park C, Bevan A, et al. Breast Cancer. In: Hansen EK, Roach M. Handbook of Evidence-based Radiation Oncology, 1st ed: 182-207. New York, NY: Springer, 2007.

10. eMedicine. Breast Cancer. http://emedicine.medscape.com/article/283561-overview. Accessed January 21, 2010.

Ginnie is bright blue.
Bridget is green.
Sheri is brown.
Zack is purple.