My Biopsy Results: “Do I Have Cancer?”

Can Surgical Excision Be Avoided?

• In general, surgical excision is favored because the morbidity of surgical breast biopsy is judged to be lower than the cost of a missed cancer.
• If surgical excision is not performed, short-term mammographic follow-up is necessary.
• Clinical risk factors of the patient should be considered; eg, genetics/family history/history of chest wall radiation.
• Some favorable subgroups have been identified in whom close surveillance rather than excision might be considered, with informed consent that there is a small ~5% or less chance of a missed cancer.

Avoid Excision if:

• • ADH: Lesions that might be observed: no mass lesion, and all or >95% of calcifications removed by core biopsy.  Caution is advised because other recent studies have been unable to identify low-risk subgroups.
  • ALH: The primary criterion to omit excision is that the ALH finding is incidental.
  • Papillary lesions: Recent data suggests that papillary lesions without atypia may be followed with imaging surveillance, especially if imaging demonstrates that the lesion has been completely removed by needle biopsy. However, caution is advised for this approach, considering multiple previous reports demonstrating upgrade rates of 20-30%.

Why Should These Lesions Be Excised

• When atypical ductal hyperplasia and papillary lesions are identified by core needle biopsy, they are associated with a significant rate of upgrade to cancer if the biopsy site is surgically excised.
• This is primarily due to (1) sampling error of the core needle biopsy technique (removing only a portion of the lesion) and (2) the fact that these lesions are histologically difficult to discriminate from cancer when only fragments of the lesion are present in the biopsy tissue.
• The goal of surgical excision is to remove the biopsy site and the original mammographic lesion that prompted the core needle biopsy in order to obtain a definitive diagnosis.

Atypical Hyperplasia of the Breast (and other high risk lesions) — What Does It Mean, Risk Assessment and Management Options

Breasts are composed of lobules, which make milk, and ducts, which carry the milk to the nipple. The lobules and ducts are both lined by two layers of cells.  When the cells lining the lobules or ducts grow, the collection of cells is called hyperplasia. Usual hyperplasia poses no risk, but when the cells grow in an irregular pattern, they can become problematic. This irregular pattern is known as atypia. Atypical cells are not pre-cancer cells, but they will increase a patient’s lifetime risk for developing breast cancer.

Atypical hyperplasia is found in approximately 10% of all benign breast biopsies.  There are two types of atypical hyperplasia based on microscopic appearance: Atypical ductal hyperplasia, also known as ADH, involves the ducts of the breast tissue and atypical lobular hyperplasia, also known as ALH, involves the lobules of the breast tissue. They are considered to be high-risk breast lesions.  Other forms of abnormal cells include lobular neoplasia, also called LIN, and lobular carcinoma in-situ, as called LCIS. Collectively, all of these cellular abnormalities are considered high risk lesions.

When high risk lesions are seen by the pathologist on a core needle biopsy performed for an abnormal mammogram or ultrasound, an open surgical biopsy may be recommended. The reason for this recommendation is that core needle biopsy samples can potentially miss a breast cancer 10-20% of the time. Atypia found on an open surgical biopsy does not require another operation but will be helpful in assessing for cancer and in calculating a patient’s risk for developing breast cancer in the future. The purpose of surgical biopsy is not to remove all of the atypical cells but rather to rule out a nearby cancer that the needle biopsy may have missed.

RISK:

Once a woman is diagnosed with a high risk lesion, she has a cumulative incidence of breast cancer (either ductal carcinoma in situ or invasive cancer) of 30% over the next 25 years. The risk of breast cancer is higher in those diagnosed with high risk lesions at a younger age, and the cumulative incidence of breast cancer appears to increase linearly overtime. However, if women with high risk lesions take medication to prevent breast cancer, their risk of developing breast cancer may be reduced by over 40% and up to approximately 80%.

PREVENTION:

Clinical trials have shown pharmacologic risk reduction (taking medication to prevent cancer) to be effective in women with high risk lesions. Approximately 97% of atypical ductal hyperplasia and 88% of atypical lobular hyperplasia has estrogen receptor staining, meaning it is stimulated by estrogen.  Because of this, medications called selective estrogen receptor modulators (tamoxifen and raloxifene) and aromatase inhibitors (exemestane, anastrozole, and letrozole) have been shown in clinical trials to effectively and significantly reduce the risk of breast cancer associated with these lesions.

Despite the evidence that chemoprevention medications work, MOST patients are reluctant to take them due to fear of side effects.  Vasomotor symptoms (hot flashes, night sweats) are not uncommon; they occurred in 60-120 per 1000 high-risk women on tamoxifen. The serious risks associated with tamoxifen and raloxifene are related to thromboembolic (clotting) events, including deep venous thromboses (blood clots in the legs) and pulmonary emboli (blood clots in the lungs), and are very infrequent.  The risk of developing clots while taking these medications ranges from 5.9 to 14 per 1000 women.  Tamoxifen (but not raloxifene or the aromatase inhibitors) is also associated with an increased incidence of endometrial (uterine) cancer of 5.5 per 1000 women, mainly in those who are postmenopausal, but the risk is still quite low overall.

SCREENING:

For individuals who have an elevated risk of getting breast cancer, enhanced screening with breast MRI is often considered. An MRI is performed in addition to an annual mammogram, not instead of a mammogram.