Surgical Anatomy of the chest

CRIMEAN FEDERAL UNIVERSITY

SURGICAL ANATOMY OF THE CHEST

BY-RUSHI DAVE

GROUP-218

Anatomy of breast

The breast is a modified sweat gland.

Development of breast

The epithelium lining of the ducts & acini of the breast is develop from ectoderm & the supporting tissue develops from mesenchyme.

ectoderm

mesoderm

Development of breast

On each side of the ventral surface of young embryos, a thickened band of ectoderm develops(the milk ridge).

It extends obliquely from axilla to inguinal region. In human, the whole of these ridge atrophies, excepting only

small portion in each pectoral region from which breast arises.

Congenital anomaly of breast

Amastia: bilateral absence of breast tissue & nipple. When breast tissue is absent unilaterally, the pectoral muscle is often absent.(3)

Polymastia: more than one breast in one or both sides.(1) Polythelia: supranumerary nipples are situated irregularly over the

breast & not on milk ridge.(2)

situation

The breast lies in the superficial fascia of the pectoral region.

foramen of langer

A small extension called the axillary tail(of Spence) pierces the deep fascia and lies in the axilla

In some normal subjects it can be palpable or seen premanstrually or during lactation.

A well developed axillary tail sometimes mistaken for mass of enlarge lymph nodes.

Extent

Vertically: it extends from the 2nd to 6th rib.

Horizontally: it extends from the lateral border of the sternum to the mid- axillary line.

Deep relations of the breast

The breast lies on the deep fascia (pectoral fascia) covering the pectoralis major.

pectoral fascia

pectoralis

major


Still deeper there are parts of four muscles, namely pectoralis major, the serratus anterior, latissimus dorsi and external oblique muscle.

pectoralis major

Serratus

anterior

latissimus dorsi external oblique


Located deep to pectoralis muscle, the pectoralis minor muscle is enclosed in clavipectoral fascia.

clavipectoral fascia

pecroralis minor

axillary fascia

clavipectoral fascia extends laterally to fuse with axillary fascia


Breast is separated from pectoralis fascia by loose areolar tissue(retromammary space).

It is thin layer of loose areolar tissue that contains lymphatics & small vessels.

retromammary pectorali

space minor

clavipectoral

fascia

axillary fascia

Because of this loose tissue the normal breast can be moved freely over the pectoralis major

Surgical importence: during removal of breast the breast is separeted from pectoral muscle in plane of retromammary space.

Structure of the breast

Structure of the breast can be studied under following heading skin, parenchyma, & stroma.

Skin

- nipple &

- areola

4th IC space

Nipple : erectile structure, covered with thick pigmented skin(which increases during pregnancy)

It contains smooth muscle fiber arranged concentrically & longitudinally.

Near its apex lies orifices of lactiferous ducts.

Areola: epithelium of areola contains numerous modified sweat glands and sebacious glands.

These glands enlarge during pregnancy(Glands of Montogomery).

It contains involuntary muscles arranged in concentric rings as well as radially in subcutaneous tissue.

Architecture of the parenchyma

Parenchyma consist of 10 to 100 lobules, each loblues is cluster of alveoli, drained by lactiferous duct, which near its termination it dilate to form lactiferous sinus.

alveoli

lactiferous lactiferous sinus

duct

.

Different portions of duct system are associated with different diseases.

Large duct-

duct papilloma

duct ectasia

Smaller duct-(during development of breast)

- fibroadenoma

-(during involution of breast)

- cyst formation

- sclerosing adenosis

The stroma

It forms the supporting framework of the gland. It is partly fibrous & partly fatty

Fibrous part: “Ligament of Cooper”-hollow conical projection of fibrous tissue filled with breast tissue, the apices of cones firmly attached to superficial fascia & to the skin.

It anchor the skin & gland to the pectoral fascia.

Fatty stroma forms the main bulk of the gland. It is distributed all over the breast, except beneath the areola & nipple.

The stroma

In cancer of the breast, the malignant cells may invade these ligaments & consequent contraction of these strands may cause dimpling of the skin.

The stroma

If the underlying growth attached to the skin, it cannot be pinched up from the lump

The stroma

If cancer cells grow along the ligament of cooper binding the breast to the pectoral fascia breast fixed to pectoralis major

It cannot then moved in the long axis of the muscle.

The stroma

If cancer cells grow along the ligament of cooper binding the breast to the pectoral fascia breast fixed to pectoralis major

It cannot then moved in the long axis of the muscle.

Blood supply

internal thoracic art.(br. of

subclavian art)

axillary supirior thoracic artery

artery acromiothoracic artery

lateral thoracic artery

branches from intercostal artery

Venous drainage: the superficial veins radiate from breast & are characterized by their proximity to skin.

They are accompanied by lymphatics & drain to axillary, internal mammary & intercostal vessels.

Phlebitis of one of these superficial veins feel like a cord immediately beneath the skin. The condition produces no discoloration & may be tensed like bowstring by putting traction on it (Mondor’s disease).

Nerve supply: the secreting tissue is supplied by sympathetic nerves(2nd-6th intercostal nerves). The overlying skin is supplied by the ant & lat branches of 4th, 5th & 6th intercostal nerves.

Axillary lymph nodes

The breast drains mainly to the axillary nodes, of which there are 5 sets

axillary vein

apical axillary nodes

lat ax.nodes

pectoralis minor

interpectoral nodes(Rotters)

anterior axillary nodes

post ax.nodes

lat thoracic v.

central axilary nodes

subscapular vein internal mammary chain

Axillary lymph nodes Anterior set:

situation- along the lateral thoracic vein under anterior axillary fold. They lie manly on 3rd r

The axillary tail of Spence is in close contact with these nodes & therefore , cancer involving this process may be misdiagnosed as enlarged node with an apparently healthy breast.

Anterior axillary nodes may be involved, by continuity of the tissue

axillary lymph nodesCentral set:

Situation- in the fat of upper part of axilla.

Intercostobrachial nerve passes outwards amongst these nodes

Intercostobrachial nerve

Enlargement of these nodes(in cancer) by pressure on the nerve, cause pain in the distribution of the nerve along the inner border of the arm.

axillary lymph nodes Apical set(infraclavicular nodes):

situation- bounded below by 1st intercostal space, behind by axillary vein, in front by the costocoracoid membrane.

They are of great importance because they receive one vessel directly from upper part of the breast & ultimately most of the lymph from the breast

A single trunk leaves the apical group on each side of the subclavian trunk, & enters the junction of jugular & subclavian vein

or may join the thoracic duct on the left.

Axillary lymph nodes levels

Level 1: lateral to lateral border of pectoralis minor

Level 3(apical groups)

Level 2 (central groups)

Level 1

(lateral groups)

Level 2: central axillary nodes located under pectoralis minor muscle.

Level 3: subclavicular nodes medial to pectoralis minor muscle. It is difficult to visualised & remove unless pectoralis muscles are sacrifised or divided.

the axillary fascial ‘tent’

Axillary lymph nodes are enclosed by layers of fascia which resembles tent lying on its side

the axillary fascial ‘tent’

Axillary lymph nodes are enclosed by layers of fascia which resembles tent lying on its side

Anterior wall: pectoralis minor & clavipectoral fascia

Posterior wall: subscapularis muscle lying on the scapula

Medial wall: deep fascia covering chest wall, upper ribs, intercostal & serratus ant muscle.

surgical importance:

n. to serratus ant.

lies here

Apex : points upwards &

medially where layers of

fascia comes into contact

with

each other.

Base : points downwards & laterally & it is

open

Surgical importance : Block dissection

of axillary lymph nodes should excise the

‘tent’intact

Lymphatic drainage of thje breast Lymphatic of the overlying skin:

These drains the integuments over the breast, but not the skin of the areola & nipple.

They pass in a radial direction & end in the surrounding nodes.

Lymphatics from outer side- goes to axillary nodes

Skin of the upper part – supraclavicular nodes & certain of the vessels may end in cephalic nodes(which lies along with cephalic vein in deltopectoral groove)

Skin of the inner part of the breast- goes to internal mammary nodes.

Lymphatics of the skin over the breast communicates across midline & unilateral disease may become bilateral by these roote.

Lymphatic drainage of thje breast

Lymphatics of the parenchyma of the breast:

2nd leading cause of death

2nd most common cancer

Incidence increases with age

All women are at risk

Breast Cancer Facts

Breast cancer staging according to TNM classification

Stage 0: Tis N o M o

Tis = carcinoma in situ

N o= no reginal lymph

node metastasis

M o= no distant metastasis

Breast cancer staging according to TNM classification

Stage 1: T1 N o M o

T 1 = tumor 2cm or less

in greatest dimension

Stage 2a:

To N1 Mo N1= metastasis

to ipsilateral

ax. Nodes

T1 N1 Mo mobile

T2 N o Mo T2= tumor>2cm

but <5cm in

greatest

dimention

Stage 2b:

T2 N1 Mo

T3 N o Mo T3= tumor size

> 5cm in

greatest

dimention

Stage 3a N2a =met to ipsilat axillary node , fixed or matted

N2b= met to ipsilat int mammary node in absence of ax. node

T o N2 M o

T1 N2 Mo

T2 N2 Mo

T3 N1 Mo

T3 N2 Mo

Stage 3b

T4a= extension to chest wall

T4b= edema(Peaud’ Orange),

T4c= both T4a& T4b

T4d= inflammatory carcinoma

T4 No Mo

T4 N1 Mo

T4 N2 Mo

T4 N2 Mo

Stage 3 c N3a= met to ipsilat infraclavicular LN

N3b= ipsilatInternal mammary& axillary LN

N3c= ipsilat supraclavicular LN

Any T

N3

Mo

Stage 4 : Any T any N + M1

M1= distant metastasis

Treatment of locally advanced carcinoma Patient with locally advanced breast cancer include –

large primary tumors(>5cm)

- tumor involving the chest wall

- skin involvement

- ulceration or satellite skin nodule

- inflammatory carcinoma

- bulky or fixed axillary node

- internal mammary or

supraclavicular node involvement

blood vessel or lymph vessel invasion

- HER 2/neu overexpression

- negative hormone receptor status

Such cancer span stages 2b, 3a & 3b disease.

Central to treatment is the concept that disease has advanced on the chest wall or regional lymph node with no evidence of distant metastasis.

Such patients are recognized to be at significant risk for development of subsequent metastasis & treatment must address the risk of both local & systemic relaps.

Till 1970s surgery alone provided poor local control, with relapses rate

- 30 – 50%

mortality rate - 70%

Similar results are reported when radiotherapy was the sole modality of treatment.

Current management includes

- surgery

- radiotherapy

- systemic therapy

Surgery for breast cancer

Simple or total mastectomy:

removal of all breast tissue, nipple areola complex, & skin


Extended simple mastectomy:

removal of all breast tissue, nipple areola complex, & skin + level 1 axillary lymph node


Modified radical mastectomy:

removal of all breast tissue, nipple areola complex, & skin + level 1 & level 2 axillary lymph nodes.


Modified radical mastectomy:

removal of all breast tissue, nipple areola complex, & skin + level 1 & level 2 axillary lymph nodes.

Neoadjuvant systemic therapy for operable breast cancer Administration of systemic chemotherapy or hormonal

therapy result in reduction of tumor size in 50 to 80% of the patients with locally advanced breast carcinoma

Preoperative or neoadjuvant therapy

can convert

Inoperable tumor that require can shrink

Tumor mastectomy large

tumor

Operable one to eligible for to allow more

lumpectomy cosmetic

lumpectomy

Chemotheraputic regimen of advanced breast cancer

C M F regimen C – cyclophosphamide M – methotrexate F – 5 flurouracil FAC regimen F – 5 flurouracil A – adriamycin(doxorubicin) C – cyclophosphamide AC regimen A – adriamycin C - cyclophosphamide

Newer agents

Trastuzumab : is a humanized murine

(Herceptin) monoclonal antibody raised

against erb B2, HER 2

surface receptor

Laptinib : a dual inhibitor of both

- EGFR

- HER 2

Hormonal therapy for breast carcinoma

Beatson , a surgeon in glasgow cancer hospital was the first to demonstrate that BL oophorectomy can lead to metastatic breast cancer.

Huggins, reemphesized oophorectomy & demonstrated the effectiveness of adrenalectomy in treatment of metastatic breast cancer.

But endocrine ablation therapy has been replaced by antiestrogen therapy.

Tamoxifen(estrogen agonist-antagonist)

is the first line treatment of estrogen sensitive breast cancer.

Endocrine- agents used in treatment of breast cancer Class Common

examples Clinical use

Selective estrogen receptor modulator(SERMS)

Tamoxifen, Raloxifen,Toremifen

Adjuvant therapy for metasttic disease

Aromatase inhibitors(AIs)

AnastrazoleLetrozoleExemestane

Adjuvant therapy for metasttic disease

Pure antiestrogenLutinizing hormone- releasing hormone(LHRH)

FluvistrantGoserelinLeuprolide

-2nd line therapy for metastatic disease-Adjuvant therapy for metasttic disease

Progestational agents

Megestrol 2nd line therapy for metastatic disease

Androgens Fluoxymesterone 3rd line therapy for metastatic disease

High dose estrogens

Diethylstilbestrol 3rd line therapy for metastatic disease

Education

Surgical Anatomy of the chest