A 50-year-old woman comes to the physician for a routine screening mammogram. An asymmetric 1.5-cm mass with calcifications is found in the upper outer quadrant of her left breast. She has no weight loss, headaches, or bone pain. She has no other medical problems and takes no medications. There is no family history of ovarian or breast cancer.
The patient's vital signs are normal. BMI is 24 kg/m². Examination reveals a palpable mass in the left upper quadrant of the left breast. She has no nipple or skin abnormalities.
A core needle biopsy of the mass confirms invasive ductal carcinoma with focal necrosis. Staining for hormone receptors (estrogen/progesterone) and HER2 is negative. She undergoes a wide-margin lumpectomy with surgical axillary lymph node staging. The tumor is 1.8 cm in diameter. She has 4 positive lymph nodes in the axilla. Imaging reveals no evidence of other metastatic disease.
Which of the following is the most appropriate next step in managing this patient?

Question

Quizplus · Accepted Answer

This patient's breast cancer is Stage IIIA (T1N2Mo) invasive ductal carcinoma with 4 involved lymph nodes (N2). Important prognostic factors for breast cancer include histopathological subtype (favorable: tubular, mucinous versus unfavorable: ductal, lobular, mixed metaplastic), estrogen receptor/progesterone receptor (ER/PR) positivity, and HER2 receptor status. These factors will guide further therapy. This patient has a triple-negative breast cancer as the tumor has negative staining for ER, PR, and HER2. Triple-negative breast cancers make up approximately 20% of all breast cancers. They tend to have a more aggressive clinical course with a unique relapse pattern. Triple-negative breast cancers tend to recur and peak at 3 years post diagnosis, with higher incidence of visceral and brain metastasis. Hormonal or HER2-targeted therapy is not indicated in these cancers (Choices A and B). Current guidelines recommend lumpectomy with surgical lymph node staging followed by chemotherapy and then radiation (Choices C and E). The goal of adjuvant chemotherapy followed by radiation is to reduce the risk of recurrence. Educational objective: Differentiation of breast cancer into subtypes is important to guide further therapy. Triple-negative breast cancer accounts for 20% of all breast cancers. Radiation therapy after chemotherapy is indicated in the adjuvant treatment of breast cancer. __________ References: Sequencing of chemotherapy and radiation therapy in early-stage breast cancer: updated results of a prospective randomized trial. (http://www.ncbi.nlm.nih.gov/pubmed/15774786) Triple-negative breast cancer. (http://www.ncbi.nlm.nih.gov/pubmed/21067385)

A 50-Year-Old Woman Comes to the Physician for a Routine