Triple-Negative Breast Cancer: Case 1 - Episode 5

Denise A. Yardley, MD: Main Choices for TNBC

Dr. Yardley cites a variety of approved non—cross-resistant agents, such as nab-paclitaxel, gemcitabine, vinorelbine, capecitabine, eribulin, ixabepilone, and/or the platinums. In anthracycline-pretreated patients, combination chemotherapy platforms based on microtubule inhibitor doublets partnered with some of these antineoplastic agents have demonstrated superior efficacy, including survival. In addition, the platinums have gained increasing attention and popularity based on the strong association of TNBC tumors with germ-line mutations in the BRCA1 gene, with at least 10% of TNBC tumors having a BRCA 1 mutation. In later lines of metastatic breast cancer therapy, other agents, such as eribulin, have also demonstrated efficacy specifically in anthracycline- and taxane-pretreated patients. Capecitabine in combination with ixabepilone demonstrated superior responses in the TNBC subset. However, overall outcomes still remain poor for TNBC, and while administration of sequential single agents is not likely to require dose reductions or treatment delays—no single agent has demonstrated superiority— treatment decisions can be selected on the basis of efficacy, toxicity profiles, schedule, and/or route of administration.

CASE 1: Triple-Negative Breast Cancer

Rebecca B. is a 48-year-old premenopausal African American woman from Tampa, Florida who works as a nursing administrator for a home healthcare company.

In December 2009, patient presented to her PCP after detecting a mass in her right upper-outer quadrant on self exam; she was referred for imaging and further evaluation.

Mammography and ultrasound revealed a 2.5-cm mass

Core biopsy revealed moderately differentiated invasive ductal carcinoma that was ER-/PgR-; HER2 staining was negative by immunohistochemistry

Patient was referred for whole-breast MRI and surgical evaluation

Patient underwent a lumpectomy of the right breast with sentinel lymph node evaluation

Sentinel lymph node evaluation was positive; patient underwent axillary lymph node dissection

Malignant cells were detected in 1 sentinel and 2 axillary nodes (total 3 of 14 LN+); tumor classified as Stage 2B (T2N1M0)

Post surgery, patient received TAC chemotherapy with docetaxel (75 mg/m2 IV day 1), doxorubicin (50 mg/m2 IV day 1), and cyclophosphamide (500 mg/ m2 IV day 1, cycled every 21 days for 6 cycles), with pegfilgrastim support

Patient received radiation therapy for 6 weeks, including ipsilateral breast and regional nodes

Patient remained disease-free for approximately 3 years

In January 2013, the patient returned to her PCP complaining of intermittent right-upper quadrant pain, fatigue, and unexplained weight loss.

A subsequent CT scan revealed visceral metastases in the liver and lung; bone scan was negative

Liver biopsy was performed and specimen was sent for ER, PR, and HER2 determinations