Breast Cancer Epidemiology and Clinical Diagnosis

Among women in the United States, breast cancer is the second most common malignancy (after skin cancer), and the second most common cause of cancer death (after lung cancer). Approximately one in eight women in the United States will develop breast cancer during their lifetime.¹ The American Cancer Society estimates that 232,340 new cases of invasive breast cancer and 64,640 new cases of non-invasive breast cancer will be diagnosed in 2013, and 39,620 women will die of breast cancer.

During the earliest stages of breast cancer, there are usually no symptoms. The process of breast cancer diagnosis is initiated by detection of an abnormality through self-examination, physical examination by a clinician, or screening mammography. Data from the Behavioral Risk Factor Surveillance System show that, in 2010, 75.4 percent of U.S. women aged ≥40 years and 79.7 percent of women aged 50 to 74 years reported having a mammogram within the past 2 years. If initial assessment suggests that the abnormality may be breast cancer, the woman may be referred for a biopsy, which is a sampling of cells or tissue from the suspicious lesion. In the United States, the most common indication for breast biopsy is the detection of suspicious abnormalities by screening mammography. Among women screened annually for 10 years, approximately 50 percent will need additional imaging, and 5–7 percent will have biopsies.^{2, 3} Over a million women have breast biopsies each year in the United States. There are currently three techniques for obtaining samples from suspicious breast lesions: fine-needle aspiration, biopsy with a hollow core needle, or open surgical retrieval of tissue. Fine-needle aspiration samples cells and does not assess tissue architecture, is generally considered less sensitive than core needle and open biopsy methods,⁴ and is used less frequently. For these reasons it will not be discussed further in this report. Core-needle biopsy, which retrieves a sample of tissue, and open surgical procedures are therefore the most frequently used biopsy methods.

Samples obtained by any of these methods are evaluated by pathologists and classified into histological categories with the primary goal of determining whether the lesion is benign or malignant. Because core needle biopsy often samples only part of the breast abnormality, there is the risk that a lesion will be classified as benign or as high risk (e.g., atypical ductal hyperplasia, [ADH]) or non-invasive (e.g., ductal carcinoma in situ, DCIS) when invasive cancer is in fact present in unsampled areas. In contrast, open surgical biopsy often samples most or all of the lesion, and it is thought that there is a smaller risk of misdiagnosis. However, while open surgical biopsy methods are considered to be the most accurate, they also appear to carry a higher risk of complications, such as bleeding or infection, compared to core needle biopsy. Therefore, if core needle biopsy is also highly accurate, women and their clinicians may prefer some type of core needle biopsy to open surgical biopsy.

Core needle biopsy may be carried out using a range of techniques. If the breast lesion to be biopsied is not palpable, an imaging method (i.e., stereotactic mammography, ultrasound, or magnetic resonance imaging (MRI)) may be used to locate the lesion. The biopsy may be carried out with needles of varying diameter, and one or more samples of tissue may be taken. Sometimes a vacuum device is used to assist in removing the tissue sample through the needle. It is thought that these and other variations in how core needle biopsy is carried out may affect the accuracy and rate of complications of the biopsy. Imaging methods may also influence the performance of open surgical biopsies because the majority of such biopsies are preceded by an image-guided wire localization procedure. In general, the impact of aspects of biopsy technique on test performance and safety are not clear.

Original Evidence Report and Rationale for the Update

In 2009, the ECRI Evidence-based Practice Center (EPC) conducted a comparative effectiveness review for core needle versus open surgical biopsy.^{5, 6} The original report provided a detailed description of the technical aspects of alternative biopsy methods and we have not repeated this information here. The original report assessed the diagnostic test performance and adverse events of multiple core needle biopsy techniques and tools, compared to open surgical biopsy, and also evaluated differences between open biopsy and core needle biopsy with regards to patient preference, costs, availability, and other factors. The key conclusions were that core needle biopsies were almost as accurate as open surgical biopsies, had a lower risk of severe complications, and were associated with fewer subsequent surgical procedures. The need for update of the 2009 report was assessed in 2010 by the RAND EPC. Several high-impact general medical and specialty journals were searched, a panel of experts in the field was consulted, and an overall assessment of the need to update the report was produced. The conclusion of the update Surveillance Report was that additional studies and changes in practice render some conclusions of the original report possibly out of date. Specifically, the Surveillance Report noted the following:

• New studies are available regarding—
  • the DCIS underestimation rate of stereotactic vacuum-assisted core needle biopsy
  • test performance of MRI-guided core needle biopsy
  • test performance of freehand automated device core needle technology
• New studies on the test performance of core needle biopsy may allow the exploration of heterogeneity for test performance or harm outcomes

On the basis of the Surveillance Report findings, an updated review of the published literature was considered necessary to synthesize all evidence on currently available methods for core needle and open surgical breast biopsy.

Key Questions

To determine the Key Questions and study selection criteria (population, intervention, comparator, outcome, timing and setting; PICOTS) for this update, we began by considering the criteria used in the original Evidence Report. On the basis of input from clinical experts during the development of our protocol, we made minor revisions to the Key Questions and study eligibility criteria to clarify the focus of the updated review. We specified the following three Key Questions to guide the conduct of the update:

Key Question 1.

In women with a palpable or nonpalpable breast abnormality, what is the test performance of different types of core needle breast biopsy compared with open biopsy for diagnosis?

• What factors associated with the patient and her breast abnormality influence the test performance of different types of core needle breast biopsy compared with open biopsy for diagnosis of a breast abnormality?
• What factors associated with the procedure itself influence the test performance of different types of core needle breast biopsy compared with open biopsy for diagnosis of a breast abnormality?
• What clinician and facility factors influence the test performance of core needle breast biopsy compared with open biopsy for diagnosis of a breast abnormality?

Key Question 2.

In women with a palpable or nonpalpable breast abnormality, what are the adverse events (harms) associated with different types of core needle breast biopsy compared with open biopsy for diagnosis?

• What factors associated with the patient and her breast abnormality influence the adverse events of core needle breast biopsy compared with the open biopsy technique in the diagnosis of a breast abnormality?
• What factors associated with the procedure itself influence the adverse events of core needle breast biopsy compared with the open biopsy technique in the diagnosis of a breast abnormality?
• What clinician and facility factors influence the adverse events of core needle breast biopsy compared with the open biopsy technique in the diagnosis of a breast abnormality?

Key Question 3.

How do open biopsy and various core needle techniques differ in terms of patient preference, availability, costs, availability of qualified pathologist interpretations, and other factors that may influence choice of a particular technique?