Pocket Medicine: The Massachusetts General Hospital Handbook of Internal Medicine (77 page)

• Breast mass (hard, irregular, fixed, nontender), nipple discharge (higher risk if unilateral, limited to one duct, bloody, associated with mass) • Special types:
Paget’s
disease → unilateral nipple eczema + nipple discharge;
inflammatory
breast cancer → skin erythema and edema
(peau d’orange)
• Metastases: lymph nodes, bone, liver, lung, brain
Screening
(
NEJM
2011;365:1025)
•
Self breast exam
(SBE): no proven mortality benefit (
JNCI
2002;94:1445);
not
recommended •
Clinical breast exam
(CBE): benefit independent of mammography not established •
Mammography
: ~20–30% ↓
in breast cancer mortality
(smaller abs. benefit in women <50 y) (
Lancet
2006;368:2053;
Annals
2009;151:727); 75% of all abnl findings benign; suspicious: clustered
microcalcifications
,
spiculated
,
enlarging
adding U/S ↑ Se, but ↓ PPV (
JAMA
2008;299:3151) • ACS/NCI recommend annual mammo + CBE beginning at age 40; USPSTF recommends beginning at 50 and biennially (
Annals
2009;151:716),
controversial
(
NEJM
2009;361:2499) • ↑ risk: screen earlier w/ CBE and mammo (age 25 in
BRCA1/2
carrier, 5–10 y before earliest FHx case, 8–10 y after thoracic RT, upon dx of ↑ risk benign disease) •
MRI
: superior to mammo in high-risk Pts; consider annually if >20% lifetime risk (eg,
FHx,
BRCA1/2
, prior chest RT) (
Lancet
2011;378:1804) •
Genetic testing
should be considered in women with strong FHx
Diagnostic evaluation

•
Palpable breast mass
: age <30 y → observe for resolution over 1–2 menstrual cycles;

age <30 y, unchanging mass →
U
/
S
→ aspiration if mass not simple cyst;

age >30 y
or
solid mass on U/S
or
bloody aspirate
or
recurrence after aspiration →
mammo
(detect other lesions)
and
either
fine-needle asp.
or
core-needle bx
clearly cancerous on exam or indeterminate read or atypia on bx →
excisional bx

•
Suspicious mammogram
with normal exam: stereotactically guided bx • MRI: detects contralateral cancer in 3% of women w/ recently dx breast cancer & negative contralateral mammogram (but PPV only 21%) (
NEJM
2007;356:1295); whether to use routinely remains unclear
Staging

•
Anatomic
: tumor size, chest wall invasion, axillary LN mets (
strongest prognostic factor
) •
Histopathologic
: type (little prognostic relevance) & grade; lymphatic/vascular invasion

In situ
carcinoma: no invasion of surrounding stroma

Ductal
(DCIS): ↑ risk of invasive cancer in
ipsilateral
breast (~30%/10 y)

Lobular
(LCIS): marker of ↑ risk of invasive cancer in
either
breast (~1%/y)

Invasive
carcinoma: infiltrating ductal (70–80%); invasive lobular (5–10%); tubular, medullary and mucinous (10%, better prognosis); papillary (1–2%); other (1–2%)

Inflammatory breast cancer
(see above): not a histologic type but a clinical reflection of tumor invasion of dermal lymphatics; very poor prognosis

Paget disease
: ductal cancer invading nipple epidermis ± associated mass

•
Biomarkers
: determine estrogen, progesterone receptor (ER/PR) and
HER2/neu
status for all invasive breast cancers • Oncotype DX 21-gene risk recurrence score has predictive and prognostic value in ER
, node
or
Pts (
JCO
2007;25:5287 & 2010;28:1829;
Lancet
2011;378:1812) • Circulating tumor DNA may serve as biomarker of met tumor burden (
NEJM
2013;368:1199)

Treatment

•
Local control
:
surgery and radiation therapy (RT)

Breast-conserving
= lumpectomy + breast RT + axillary node dissection (ALND) is equivalent to
mastectomy
+ ALND (
NEJM
2002;347:1227); contraindications: multicentric disease, diffuse microcalcifications, prior RT, pregnancy, ? tumor >5 cm

Sentinel lymph node dissection (SLND)
prior to ALND preferred if w/o palp axillary LNs; T1-2 w/
SLND & Rx w/ lumpect./RT/chemo may not need ALND (
JAMA
2011;305:569)

Radiation therapy
(RT) after mastectomy for ≥4
LN, tumor >5 cm or
surgical margins → ↓ locoregional recurrence and ↑ survival (
Lancet
2011;378:1707)