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"Medical Journeys" is a set of clinical resources reviewed by physicians, meant for the medical team as well as the patients they serve. Each episode of this journey through a disease state contains both a physician guide and a downloadable/printable patient resource. "Medical Journeys" chart a path each step of the way for physicians and patients and provide continual resources and support, as the caregiver team navigates the course of a disease.

Approximately 2.3 million cases of breast cancer were diagnosed worldwide in , and most were found with breast imaging. There are two basic types of breast biopsy -- needle and surgical.

Needle Biopsy

Fine-needle aspiration () biopsy is performed using a small needle to obtain samples of tissue and fluid from solid or cystic breast lesions. FNA is indicated for patients with a mammographic abnormality or palpable breast lesions.

Core needle biopsy () removes a small tissue sample, through a very small incision, with a hollow-core needle. CNB is done with imaging guidance, such as stereotactic radiography, ultrasound, or MRI. CNB can be done with .

Vacuum-assisted devices (VADs) pull tissue into a terminal biopsy aperture under negative pressure. The tissue is then cut from the breast by a cannula as it passes over the aperture and seals the device. Immediately after sampling, a small amount of sterile saline and anesthetic is infused through the device to numb adjacent tissue. Simultaneously, the infused fluid and negative pressure pull the sample into a collection reservoir that can be emptied as needed throughout the procedure.

The process is repeated until an adequate sampling is obtained. Benefits include the ability to sample a cystic solid mass and obtain multiple samples without removing the biopsy device, although VAD presents challenges when performing multiple biopsies within the same breast.

devices have an aperture at the distal end that is propelled forward from potential energy stored within the corresponding spring, also known as a throw. A cutting cannula is deployed over the aperture, a sample is taken, the device is removed, and tissue samples are collected after re-exposing the aperture and rolling the device onto a sterile gauze or into a tissue cup.

This process can be repeated as needed. Benefits include cost-effectiveness, simplicity, and ability to perform multiple biopsies of separate lesions within the same breast quadrant. However, there is trauma tied to repeat removal and re-introduction, along with potential complications associated with air entering the imaging field.

Surgical Biopsy

The may be an incisional biopsy, which removes only part of the abnormal area, or an excisional biopsy, which removes the entire tumor. A margin or edge of normal breast tissue around the tumor may also be removed, depending on the reason for the biopsy. In comparison, axillary lymphadenectomy, also called , is a surgical procedure where the lymph nodes are dissected out within the axilla en bloc.

Surgical biopsy requires preoperative localization to guide the procedure. Localization of palpable breast masses can be done manually by palpation or with imaging guidance via mammography, MRI, or ultrasound. There are different ways of performing localization including wire and non-wire. is done most often now.

During wire localization, a wire is placed in the breast percutaneously. The distal wire segment is positioned adjacent to the abnormality and the proximal wire segment stays outside the breast. Because the wire has an external component, the wire's position should not be disturbed pre-surgery. Wire localization requires a higher level of patient compliance.

include radioactive and magnetic seeds, radar reflectors, and radiofrequency identification tags. These devices are placed percutaneously within or adjacent to the target breast lesion, and are detected intraoperatively via a probe outside the breast. They can be placed days in advance of surgical biopsy and at the patient's convenience. This method avoids wire-related challenges and complications.

Stereotactic Biopsy

This technique use , and is often done for calcifications or small masses/abnormal areas that are not seen on ultrasound.

New Tools

is an emerging, noninvasive diagnostic tool that evaluates biomarkers in the blood and other body fluids. Liquid biopsies involve such as circulating tumor cells (CTCs), circulating tumor DNA (ctDNA), and tumor extracellular vesicles. These entities are then analyzed for the genomic and proteomic data contained within them.

Several types of liquid biopsies have been approved by FDA:

• CellSearch Circulating Tumor Cell test for monitoring advanced breast cancer and other solid tumors

• FoundationOne Liquid CDx is approved for use in people with breast cancer and other solid tumors

• Guardant360 CDx as a for advanced or metastatic breast cancer

Some of the genetic mutations that are being tested for in breast cancer include ESR1 and PIK3CA. There are some early data looking at prognostication with ctDNA in early-stage breast cancer and predictions of recurrence, but it is not yet standard of care to use ctDNA in early-stage breast cancer.

Sentinel Lymph Node Biopsy (SLNB) and Staging

is indicated as part of the staging work-up of early-stage breast cancers since they can spread to axillary lymph nodes. SLNB allows for without a formal axillary dissection.

In comparison, axillary lymphadenectomy, also known as axillary lymph node dissection (), is a procedure where a surgeon dissects out the lymph nodes within the axilla en bloc. At the time of surgery, the lymph node needs to be sampled, and options for sampling are SLNB versus ALND.

Breast cancer is determined clinically via physical examination and imaging studies done pretreatment. Stage is determined pathologically by examination of the primary tumor and regional lymph nodes after definitive surgical treatment. Staging is done to place patients into risk categories that define prognosis and guide treatment.

Breast cancer is commonly staged using the American Joint Committee on Cancer () staging system, which incorporates clinical and pathological evaluations, as well as tumor biology and prognostic biological markers.

For more on staging, see Part 1 of this Medical Journeys series.

Pathology

Noninvasive are generally placed into two major types: lobular carcinoma in situ (LCIS) and ductal carcinoma in situ (DCIS). LCIS will conform to the outline of the normal lobule with expanded and filled acini. DCIS is more morphologically heterogeneous than LCIS.

There are four broad types of DCIS based on pathology: papillary, cribriform, solid, and comedo. Papillary and cribriform types of DCIS are generally lower-grade lesions that may take longer to transform into invasive cancer. Solid and comedo DCIS are generally higher-grade lesions.

Breast cancer can be divided very broadly into ductal and lobular histologic types, although there are other rare subtypes. Invasive ductal cancer tends to grow as a cohesive mass, and can take on differentiated features, such as infiltrating cells that form small glands lined by a single row of the bland epithelium (infiltrating tubular) or infiltrating cells that secrete mucin and seem to float in this material (mucinous or colloid). Tubular and mucinous tumors are usually low-grade lesions.

Invasive lobular carcinoma is composed of non-cohesive cells individually dispersed or organized in a single-file linear pattern in a fibrous stroma. It is generally usually associated with lobular carcinoma in situ.

Post-Biopsy

After biopsy, patients may have bruising or swelling at the , which should resolve in a week with appropriate care, such as application of ice packs to reduce swelling. For 3 days post-biopsy, patients should be discouraged from lifting anything heavier than 5 lb, or from engaging in strenuous exercise, such as running. They also should not bathe, swim, or soak the biopsy site under water, but they may shower 24 hours after the biopsy.

Possible of a breast biopsy are prolonged bleeding from the biopsy site or infection near the biopsy site.

A patient with a biopsy that results in a cancer diagnosis should be referred to a breast cancer specialist. Additional imaging, lab tests, or surgery may be required.

Read Part 1 of this series: Breast Cancer -- The Basics of Diagnosis, Staging, and Treatment