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Anatomical basis of Spread of Breast
CarcinomaJibran Mohsin
Resident, Surgical Unit ISIMS/Services Hospital, Lahore
Surgical AnatomyBr
east
Glandular tissue -Mammary Gland (accessory female reproductive
tissue)
Parenchyma(Functional component)
15-20 lactiferous ducts Ductules lobules
Stroma(structural/supportive
component)Subcutaneous tissue (fat)
Surgical Anatomy
Mammary glands are modified sweat glands
Therefore they have no special capsule or sheath
Protuberant conical form with roughly circular base of cone having diameter of 10-12 cm
Surgical Anatomy
Gross anatomy boundaries: Second/third to inframammary fold (sixth/seventh rib) Lateral border of sternum to anterior or mid axillary line
Surgical Boundaries: Clavicle above to 7th or 8th ribs below Midline to the edge of latissimus dorsi posteriorly (post axillary line)
Significance: During mastectomy, whole of tissue breast(i.e. surgical boundaries) MUST be
excised.
Surgical Anatomy
Surgical Anatomy
Breast bed (posterior/deep surface)
2/3rd formed by pectoral fascia overlying the pectoralis major Rest by fascia overlying the serratus anterior Inferiorly, overlying external oblique and upper extent of rectus sheath Between investing fascia of breast and pectoral fascia is a loose connective tissue
plane or potential space - retro mammary space (bursa)
Significance: This plane containing a small amount of fat allows the breast some degree of movement
on pectoral fascia and This is plane of dissection during mastectomy
Surgical Anatomy
Significance –Retromammary space/bursa
Breast elevates when pectoralis major contracts (sign of advanced cancer) if cancer cells
spread deeply directly to invade Retromammary space Deep pectoral fascia overlying pectoralis major,
or metastasis to interpectoral(rotter’s) nodes.
Patient places her hands on her hips and press while pulling he elbows forward to tense her pectoral muscles
Surgical Anatomy
Axillary process or tail (of Spence): Small part of mammary gland may extend along the inferolateral edge of
posterior major toward the axillary fossa (armpit)
Significance: In some normal subjects it is palpable and in a few, it can be seen
premenstrually or during lactation If well-developed, sometimes mistaken for a mass of enlarged lymph nodes or a
lipoma or lump(tumor)
James Spence (1812-1882)Scottish surgeon
* Upper outer quadrant contains greater volume of tissue than others quadrants (hence most common site of carcinoma)
Surgical Anatomy
Suspensory ligaments (of Cooper-1840): Hollow conical projections of condensed fibrous connective tissue filled
with breast tissue Apices of the cones are attached firmly to the superficial fascia and
thereby to the dermis of skin overlying the breast
Significance: Well developed in superior part of breast help support the mammary gland
lobules Account for the dimpling of the skin overlying a carcinoma (get shorten due to
infiltration of malignant cells)
Sir Astley Paston Cooper(1768-1841)
British Surgeon
Surgical Anatomy
Lobule: Basic structural unit of mammary gland Number and size vary enormously (most numerous in young women) From 10 to > 100 lobules empty via ductules into lactiferous duct, of
which there are 15 – 20, usually opens independently on the nipple.(Each duct represents one lobe of breast)
Each lactiferous duct is lined with a spiral arrangement of contractile myoepithelial cells
Deep to areola each duct has a terminal ampulla – lactiferous sinus, a reservoir for milk or abnormal discharges. Involved in let-down reflex.
Ducts converge toward the nipple like the spokes of bicycle wheel
Surgical Anatomy
Areola (L. small area)
Circular pigmented area of skin surrounding the nipple Epithelium contains numerous sweat glands and sebaceous glands,
latter enlarge during pregnancy and serve to lubricate the nipple during lactation (Areolar glands or glands of Montgomery)
portions of the gland visible on the skin's surface are called "Montgomery tubercles". (1837)
Contains involuntary muscle arranged in concentric rings as well as radially in subcutaneous layer
William Fetherstone Montgomery
( 1797 – 1859)Irish Obstetrician
Surgical Anatomy
Nipple (derived from old English word neb, meaning face/nose/beak)
Conical or cylindrical prominences in the centers of the areola Thick skin with corrugations i.e.
No fat, hair or sweat glands Near its apex lie orifices of lactiferous ducts
Contains smooth muscle fibers arranged concentrically and longitudinally; thus it is an erectile structure, which points outwards.
Route of Spread of Malignant tumors
Tum
or Bengin
Malignant(cancer)
Epithelium(parenchyma) Carcinoma Lymphatic
spreadConnective
tissue(stroma)
Sarcoma Hematogenous spread
Axilla
Axilla
Apex Outer border of 1st rib, sup border of scapula, post border of clavicle
Floor Skin (visible part of axilla)
Medial Serratus anterior, ribcage
Lateral Intertubercular sulcus of humerus
Anterior Pectoralis major & minor
Posterior Subscapularis(above), Latissimus dorsi & teres major (below)
Axillary Lymph nodesLevel(with respect to pectoralis minor)
Group Relation to Axillary fossa
Number of nodes
Relation to adjacent structure Drainage area
Level I Lymph nodes(lateral or below the lower border of Pectoralis minor)
Axillary vein group(Humeral group)
Lateral group 4-6 Medial or posterior to axillary vein Upper extremity
External mammary group
Anterior or pectoral group
5-6 Along lower border of pectoralis minorContiguous with lateral thoracic vessels
Lateral aspect of breast
Scapular group Posterior or subscapular group
5-7 Along posterior wall axilla at lateral border of scapulaContiguous with subscapular vessels
Lower posterior neckPosterior trunkPosterior shoulder
Level II Lymph nodes(superficial or deep to pectoralis minor)
Central group 3-4 sets Embedded in fatImmediately posterior to pectoralis minor
Above 3 groupsDirectly from breast
Interpectoral group(Rotter’s Lymph nodes)
1-4 Interposed between pectoralis major and pectoralis minor
Directly from breast
Level III Lymph nodes(medial or above the upper border of pectoralis minor)
Subclavicular group
Apical group 6-12 sets Posterior and superior to upper border of pectoralis minor
All other groups of axillary lymph nodes
Josef Rotter (1857-1924)German surgeon
Axillary Lymph nodes
Axillary Lymph nodes
Axillary nodes clavicular (infra and supraclavicular) lymph nodes subclavian lymphatic trunk (drains upper limb)
Parasternal lymph nodes bronchomediastinal trunk (drains thoracic viscera)
Venous angle(Junction of internal jugular and subclavian vein)
Axillary Lymph nodes
Parasternal (internal mammary) lymph nodes
Afferent: Lymph vessels that accompany the perforating branches of the internal mammary
artery enters into parasternal (internal mammary) group of lymph nodes
Site: Lie along the internal mammary vessels dep to plane of costal cartilages Drain posterior 1/3rd of the breast Not routinely dissected although they were once biopsied for staging.
Efferent: Drains into bronchomediastinal lymphatic trunk (draining thoracic viscera)
Lymphatic Drainage
Lymphatic DrainageNi
pple
, Are
ola
& Lo
bule
s (L
ymph
atic
plex
uses
– in
terlo
bula
r co
nnec
tive
tissu
e an
d wa
lls o
f lac
tifer
ous
duct
s) Subareolar lmyphatic plexus
> 75(~85) % (especially from lateral half) drains to axillary
lymph nodes
Intially to anterior or pectoral nodes for most part
Some lymph drain directly to other axillary nodes (post, central, apical-
upper part)
Interpectoral
Deltopectoral
Supraclavicular
Inferior dep cervical nodes
Most of rest (esp Medial half) -
parasternal lymph nodes
Opposite breast
Subdiapharmatic inferior phrenic lymph
nodes(inferior half)abdomen
Lymphatic Drainage
Skin (excluding nipple and
areola)
Ipsilateral
axillary
Inferior deep cervical
Infraclavicular
Bilateral Parasternal
Sentinel node
Defined as 1st lymph node draining the tumor-bearing area of the breast.
Absence of enlarged axillary lymph nodes is no guarantee that metastasis from breast cancer has not occurred because malignant cells may have passed to other nodes, such as infraclavicular and supraclavicular lymph nodes. Directly.
Peau d’orange
Due to blockage of subareolar lymphatic plexus by metastatic cells (lymphedema)
In turn causes deviation of nipple and thickened leather-like appearance of skin
Prominent or puffy skin between dimpled pores orange –peel appearance (peau d’orange sign)
Larger dimples (fingertip size or bigger) due to cancerous invasion of glandular tissue and fibrosis (fibrous degeneration), causing shortening, places traction on suspensory ligaments.
Subareaolar breast cancer may cause inversion of nipple by similar mechanism involving lactiferous ducts
Arterial supply
Medial mammary arteries/ branches of perforating branches and 2nd 3rd and 4th anterior intercostal branches of the internal thoracic/mammary
artery (origin: subclavian artery)
Lateral mammary branches of Highest thoracic Lateral thoracic artery (origin: 2nd part of axillary artery) Pectoral branches of thoracoacromial artery lateral cutaneous branches of posterior intercostal arteries (origin: thoracic aorta) in
2nd, 3rd and 4th intercostal spaces.
Arterial Supply
Venous drainage
3 Principal groups of veins
1. Perforating branches of internal thoracic vein
2. Perforating branches of posterior intercostal veins
3. Tributaries of the axillary vein
Batson’s (1940) vertebral venous plexus
A network of valve less veins in the human body that connect the deep pelvic veins and thoracic veins (draining the inferior end of the urinary bladder, breast and prostate) to the internal vertebral venous plexuses
Invests the vertebrae and extends from the base of the skull to the sacrum
Posterior intercostal veins azygous/hemiazygous system of veins alongside bodies of vertebrae Batson vertebral venous plexus internal vertebral venous plexus surrounding the spinal cord
May provide a route for breast cancer metastases to vertebrae, skull, pelvic bones and CNS.
Oscar Vivian Batson(1894-1979)Anatomist
Spread to overlying skin
Available at surgicalpresentations