Breast

Breast cancer remains the most common cancer diagnosed among women in the US, accounting for about 32% of new cancer cases in women.¹ Approximately 1 in 8 women in the US will be diagnosed with invasive breast cancer during their lifetime, and 1 in 43 will die from the disease.^1,2 Breast cancer incidence has continued to rise over the last decade, but the good news is that early diagnosis dramatically improves a patient’s 5-year relative survival rate (99% for localized stage cancer).¹

Awareness of testing options is key in continuing the battle against breast cancer. Breast cancer includes a range of different subtypes with different biological, medical, and prognostic features, which is why Quest Diagnostics strives to provide a robust portfolio of tests and services across the care continuum, from screening to survivorship.

The Hereditary Breast Cancer Panel includes 18 genes associated primarily with hereditary breast—and possibly other—cancers. This can include, but is not limited to, cancers of the breast, colon, endometrium, stomach, urinary tract, ovary, pancreas, prostate, and other tissues. Individuals with a positive result (pathogenic or likely pathogenic variant detected) have an increased risk for developing certain cancers relative to that of the general population.

Cancer can be more common in some families than others. Quest Diagnostics BRCA Panel Plus tests for genes predominantly associated with breast cancer, including BRCA1 and BRCA2. These tests are available for adults of all ages, but it’s best to talk with your doctor or genetic counselor to decide if genetic testing is right for you. Getting tested can also give important information to your family that can help family members understand their risk for cancer.

The AmeriPath® national network of board-certified pathologists provides comprehensive pathology services utilizing state-of-the-art technologies, including immunohistochemistry and molecular diagnostics.

We are an industry leader in breast tumor pathology expertise. Combined with our comprehensive test menu and advanced technology, our expertise ensures you receive accurate diagnostic, prognostic, and therapeutic information promptly.

Quest Diagnostics maintains an up-to-date and robust selection of immunohistochemical stains to gather diagnostic insight for the patient, including companion diagnostics that can be used to inform downstream treatment selection. Examples of our extensive menu are provided below.

PD-L1 is a protein that protects normal cells from destruction when T-cells are activated. Some cancer cells take advantage of this protective role by highly expressing PD-L1 to evade the immune system. 

The HER2 (also known as ERBB2 or HER-2/neu) protooncogene encodes a tyrosine kinase receptor that is a member of the epidermal growth factor receptor (EGFR) family. HER2 status can be assessed by detecting either protein overexpression with immunohistochemistry (IHC) or gene amplification with in situ hybridization (ISH). HER2 status determines patient eligibility for HER2-targeted therapy.

Estrogen and progesterone receptor assays are routinely performed on breast carcinomas to assess responsiveness to endocrine therapy and prognosis.

In breast cancer development, the expression of Ki-67 (also known as MIB-1) is strongly associated with cancer proliferation and is a known indicator of prognosis and outcome.

The Prosigna® Breast Cancer Gene Signature Assay is a prognostic indicator for distant recurrence-free survival at 10 years in postmenopausal women. Prosigna should be used in conjunction with other clinicopathological factors.

Precision medicine is an emerging approach for disease prevention and treatment that takes individual variability into account. This next-generation sequencing (NGS) panel, along with the computational resources and tools that process and analyze the data, allows the characterization of individual patients and tumor types. Guidelines exist for using results from many of these genes for selection of FDA-approved therapies.

This NGS panel can accurately and sensitively sequence more target genes with less DNA, with reduced cost, time, and labor as compared with more limited sequencing methods, and the physician can become aware of alternative treatments available to the patient based on presence of mutations in other genes the physicians might not have considered. Microsatellite instability (MSI) and tumor mutation burden (TMB) are also included. The panel allows the generation of diverse data obtained and analyzed in real time, enabling enrollment in specific clinical trials and adaptation of treatment strategies.

Sensitivity matters when looking for the lowest levels of disease, such as residual disease after surgery or response to adjuvant chemotherapy. Haystack MRD minimizes false negatives by detecting ultralow levels of ctDNA, providing confidence in therapeutic decisions.³