Transcript שקופית 1

IMAGING OF THE AXILLA
Dr. Varda Stahl-Kent
Department of Radiology and the M.
Fanny Breast Institute
ASSAF HAROFE MEDICAL CENTER
WHY IS IMAGING OF THE AXILLA AN
IMPORTANT PART OF BREAST IMAGING?
In cases of breast cancer axillary
adenopathy has high correlation with
prognosis.
– The number of nodes
– The level of axillary involvement .
– Extranodal extention
THE AXILLA -ANATOMIC BOUNDARIES
Anterior wall:pectoralis major and minor.
Posterior wall:subscapularis, latissimus
dorsi and teres major muscles.
Medial wall: serratus anterior muscle.
Lateral wall: bicipital groove of humerus.
CONTENTS OF THE AXILLA
Fat, lymph nodes, arteries, veins and
nerves.
Dense connective tissue that surrounds
nerves and vessels.
May contain accessory breast tissue.
ANATOMY OF VESSELS AND NERVES
SURGICAL LYMPH NODE LEVELS
Level 1- low axillary group
– L.N. lateral/inferior to pectoralis minor
– Includes scapular, axillary vein and pectoral
LOWER L.N. IN THIS GROUP ARE “SENTINEL”
Level 2 – Rotter nodes – mid-axillary group
– Deep/posterior to pectoralis minor
– Includes central and interpectoral and portions of
subclavicular
– LEVEL 1 AND 2 ARE INCLUDED IN ALND.
Level 3 – high or apical axillary group
– Medial and superior to pectoralis minor
LYMPH NODES AND LYMPHATICS
75% of drainage via lateral and medial
trunks extending from areola to axilla
25% via internal mammary chain
Anastomotic lymphatic channels may
communicate with contralateral skin and
breast.
IMAGING OF THE AXILLA
Should include axillary vein and artery, fat
or breast tissue, lymph nodes and possible
abnormality.
Accessory (ectopic) breast tissue in the
axilla – common.
Benign and malignant primary tumors may
occur in the axilla.
NORMAL AXILLARY ANATOMY
NORMAL AXILLARY VESSELS
NORMAL AXILLARY VESSELS
NORMAL AXILLARY LYMPH NODE
PHYSIOLOGY OF THE NORMAL LYMPH
NODE
Blood enters and is drained through the hilum.
Afferent lymphatic channels enter through the
capsule.
The fluid then flows to the subcapsular sinus, the
cortical sinuses, and the l.n. mediastinum, to
enter the medullary sinusoids.
When transcapsular arteries develop, it means
that the l.n. bears metastases.
IMAGING AXILLARY L.N. WITH
ULTRASOUND
Level 1, 2 and sometimes level 3 axillary nodes,
and sometimes also internal mammary nodes
can be seen.
Normal lymph node appearance
– Usually elliptical, with long and short axes,
hypoechoic cortex , hyperechoic fatty hilus.
– May be longer than 2 cms.
– Normal hilar vessels on Doppler exam.
– Internal mammary nodes smaller than axillary, and
morphology difficult to assess.
CORTEX AND SINUS OF A NORMAL
LYMPH NODE
NORMAL AXILLARY LYMPH NODES
LYMPH NODE REPLACED ALMOST
ENTIRELY BY FAT
HILAR VESSEL OF A LYMPH NODE
METASTASES TO AXILLARY L.N.
Malignant cells travel from breast to axilla in
stepwise fashion.
– Level 1 affected first, followed by 2 then 3.
– Skip metastases <5%.
Likelihood of axillary involvement varies with
location of breast primary.
–
–
–
–
Upper outer
Lower outer
Upper inner
Lower inner.
AXILLARY ADENOPATHY - IMAGING
Enlarged (usually >2 cm).
Absent or diminutive fatty hilum.
On mammography: Dense, rounded or irregular.
On ultrasound: Cortical thickening
– Asymmetric - favors metastatic disease.
– Uniformly thickened cortex - favors reactive
adenopathy.
Spiculated margins suggest extranodal
extension.
SHAPE IS MORE IMPORTANT THAN SIZE.
LONG TO SHORT AXIS RATIO <1.4 PATHOLOGIC
AXILLARY ADENOPATHY – IMAGING (2)
Sensitivity for metastases 56 – 72%,
specificity 70 – 90%.
Color Doppler:
– Peripheral flow, transcapsular vessels favor
malignancy (50% of nodes with peripheral
flow – malignant, low likelihood of benign L.N)
METASTATIC AXILLARY LYMPH NODES
DIFFERENT APPEARANCES OF
ABNORMAL LYMPH NODES
ECCENTRIC CORTICAL THICKENING
WITH OUTWARD AND INWARD BULGES
PERINODAL INVASION
INFLAMMATORY
METASTATIC
ONE FEEDING VESSEL
MULTIPLE VESSELS
BILATERAL ADENOPATHY CAUSED BY
VIRAL INFECTION
REACTIVE LYMPH NODE PER OPEN
BIOPSY
ENLARGED LEVEL 2 NODES
AXILLARY LYMPH NODES IN LYMPHOMA
BREAST CA.
BILATERAL AXILLARY ADENOPATHY LYMPHOMA
D.D. OF AXILLARY ADENOPATHY
Metastases from breast ca.
Other metastases – melanoma, lung, ovary, thyroid
Primary breast ca.
Silicone from current or prior rupture.
HIV
Lymphoproliferative diseases
Rheumatoid arthritis / collagen vascular diseases
Previous granulomatous infection – T. B., Histoplasmosis
Gold deposits
MALIGNANT ETIOLOGIES 55%
F.N.A. PERFORMED FOR EVALUATION
WORKUP OF AXILLARY ADENOPATHY
Clinical presentation of breast ca. as palpable
axillary lymph nodes is rare (0.3 – 0.8%)
If F.N.A. positive for breast ca. and primary is
not demonstrated, M.R.I should be performed
Even if primary is not demonstrated, the patient
is treated as having an ipsilateral breast ca.
If F.N.A does not diagnose the cause for
adenopathy, follow-up in 3 months.
SMALL PRIMARY WITH METASTASES
METASTATIC L.N, NORMAL MAMMOGRAM
ENHANCING MASS ON M.R.I
DIAGNOSIS AND TREATMENT OF PATIENTS
WITH AXILLARY METASTASES FROM BREAST
CANCER
Sentinel lymph node biopsy performed
intraoperatively if lymph nodes are not
proven to contain metastases (by F.N.A or
trucut biopsy)
If sentinel lymph node is affected- continue
to ALND.
If more than 4 nodes affected – irradiation
of the axilla
INTERNAL MAMMARY LYMPH NODES
Lie between the pleura and the intercostal
muscles in the first to third intercostal spaces,
within 1-2 cm of the lateral sternal border.
Adjacent to the internal mammary artery and
veins.
Smaller than axillary L.N., about 0.6 cm.
About 20% of patients may have metastases to
internal mammary lymph nodes, but usually
axillary metastases occur first.
INTERNAL MAMMARY LYMPH NODE
ACCESSORY BREAST TISSUE IN AXILLA
Ectopic breast tissue – mammary tissue that
persists along the embriologic “milk line.”
Accessory nipples and breasts may occur.
Physiologic changes may occur during
menstrual cycle, pregnancy and postpartum.
Adenomas and fibroadenomas may occur.
Carcinoma may occur (less than 1% of breast
carcinomas occur in the axilla)
ACCESSORY BREAST
GALACTOCELE IN AXILLARY BREAST
TISSUE
CALCIFICATION WITHIN AXILLARY
LYMPH NODES - D.D.
Granulomatous diseases – T.B,
Histoplasmosis, sarcoidosis; fat necrosis.
Usually coarse.
Metastatic breast ca. – amorphous and in
peripheral location.
Extramammary metastases: ovarian,
thyroid.
Gold deposits – can be punctate.
Silicone deposits.
PRIOR GRANULOMATOUS INFECTION
SILICONE CONTAINING LYMPH NODE
NON NODAL AXILLARY DENSITIES
Deodorant clumps.
Talc within skin lesion
Retained catheter.
SEBACEOUS CYST
POSTOPERATIVE SEROMA IN THE
AXILLA – CLEAR FLUID
MULTISEPTATED SEROMA
SUMMARY
Imaging of the axilla is an important part of
breast imaging.
U.S. – the method of choice, also for guidance
for cytological or histological diagnosis
If metastases diagnosed – ALND performed for
definite staging.
Other pathologies such as inflammatory
diseases or malignancy other than breast ca.,
treated accordingly.