NCCN VERSION 2 2015

The NCCN Guidelines® and this illustration may not be reproduced in any form without the express written permission of NCCN®.

MS-14

NCCN Guidelines Index

Breast Cancer Table of Contents

Discussion

NCCN Guidelines Version 2.2015

Breast Cancer

re-excision should be considered for a higher radiation boost dose to

the tumor bed.

Several studies of women with early-stage breast cancer treated with

breast-conserving therapy have identified young age as a significant

predictor of an increased likelihood of IBTR after breast-conserving

surgery.

110-113

Risk factors, such as a family history of breast cancer or a

genetic predisposition for breast cancer (eg,

BRCA1/2

or other

mutation), are more likely to exist in the population of young women

with breast cancer, thereby confounding the independent contributions

of age and treatment to clinical outcome.

114

Survival outcomes for young

women with breast cancer receiving either lumpectomy or mastectomy

are similar.

115

Several studies have been reported using accelerated partial breast

irradiation (APBI) rather than whole breast irradiation following complete

surgical excision of in-breast disease. The panel generally views the

use of APBI as investigational, and encourages its use within the

confines of a high-quality, prospective clinical trial.

116

For patients who

are not trial eligible, recommendations from the American Society for

Radiation Oncology (ASTRO) indicate that APBI may be suitable in

selected patients with early-stage breast cancer and may be

comparable to treatment with standard whole-breast RT.

117

Patients

who may be suitable for APBI are women 60 years of age and older

who are not carriers of a known BRCA1/2 mutation and have been

treated with primary surgery for a unifocal stage I, ER-positive cancer.

Tumors should be infiltrating ductal or have a favorable histology,

should not be associated with an extensive intraductal component or

LCIS, and should have negative margins. Thirty-four Gy in 10 fractions

delivered twice per day with brachytherapy or 38.5 Gy in 10 fractions

delivered twice per day with external beam photon therapy to the tumor

bed is recommended. Other fractionation schemes are under

investigation.

Studies have suggested that the ASTRO stratification guidelines may

not adequately predict IBTR following APBI.

118,119

Follow-up is limited

and studies are ongoing.

Only limited data are available on the survival impact of mastectomy

contralateral to a unilateral breast cancer.

120

Analysis of women

included in the SEER database treated with mastectomy for a unilateral

breast cancer from 1998 to 2003 showed that contralateral mastectomy

performed at the time of treatment of a unilateral cancer was associated

with a reduction in breast cancer-specific mortality only in the population

of young women (18–49 years of age) with stage I/II, ER-negative

breast cancer (HR, 0.68; 95% CI, 0.53–0.88;

= .004).

121

The 5 year

breast cancer survival for this group was slightly improved with

contralateral mastectomy vs. without (88.5% vs 83.7%, difference =

4.8%).

121

The panel recommends that women with breast cancer who

are ≤35 years or premenopausal and carriers of a known

BRCA1/2

mutation consider additional risk reduction strategies following

appropriate risk assessment and counseling (see

NCCN Guidelines for

Breast Risk Reduction

and

NCCN Guidelines for Genetic/Familial

High-Risk Assessment: Breast and Ovarian

). This process should

involve multidisciplinary consultations prior to surgery, and should

include a discussion of the risks associated with development of a

contralateral breast cancer as compared with the risks associated with

recurrent disease from the primary cancer. Except as specifically

outlined in these guidelines, prophylactic mastectomy of a breast

contralateral to a known unilateral breast cancer treated with

mastectomy is discouraged by the panel. The use of a prophylactic

mastectomy contralateral to a breast treated with breast-conserving

surgery is very strongly discouraged in all patients.