For medical, nursing and physiotherapy undergraduates, and postgraduates

1. MAMMARY GLAND
DR. SUNDIP CHARMODE
ASSOCIATE PROFESSOR
DEPARTMENT OF ANATOMY
AIIMS RAJKOT

2. INTRODUCTION
• The breast is a modified sweat
gland and lies in the superficial
fascia of pectoral fascia.
• No distinct fibrous capsule.

4. EXTENT
• Vertically: from second to sixth rib in the mid–clavicular line
• Horizontally: from the lateral border of sternum to the mid-axillary
line along the fourth rib

5. MAMMARY BED
• The base of the gland rests upon the
following structures:
• Pectoralis major: in medial 2/3rd
• Serratus anterior: in lateral 1/3rd
• External oblique aponeurosis: Infero-medial
quadrant
• Deep projections from the glandular
parenchyma sometimes penetrate the
superficial part of pectoralis major

6. Parts, Shape & Position of the Gland
• It is conical in shape.
• It lies in superficial fascia of the
front of chest.
• It has a base, apex and tail.
• Its base extends from 2nd to 6th
ribs.
• It extends from the sternum to the
midaxillary line laterally.
• It has no capsule.

7. MAMMARY BED
• Retro-mammary space: loose
connective tissue intervenes between
the base of gland and the deep fascia
covering the structures of the
mammary gland.
• Normal breast moves freely over P.
Major; in invasion of breast
carcinoma it is fixed.

8. MAMMARY BED
• Axillary tail of Spence: A tail like
projection from the upper and outer
quadrant of gland enters axilla
through opening in axillary fascia.
‘Foramen of Langer’

9. Axillary Tail of Spence

11. FEATURES IN THE SKIN
• Nipple:
• Conical or cylindrical projection below the centre of breast,
at the level of 4th inter-costal space in nulliparous.
• Pierced by 15-20 lactiferous ducts
• Contain circular and longitudinally disposed smooth
muscles
• Rich nerve supply and provided by sensory receptors for
suckling.

12. FEATURES IN THE SKIN
• Areola:
• It is a pigmented circular area of skin around
the base of the nipple.
• The pigmentation is irreversibly darkened
after first pregnancy
• Outer margin of areola- number of modified
sebaceous glands- enlarged during pregnancy
– ‘Tubercles of Montgomery’- Oily
secretion.
• Besides these glands, areola contains sweat
glands and accessory mammary glands.

13. FEATURES IN THE SKIN
• Areola:
• The skin is devoid of hair and
subcutaneous fat.
• Beneath the areola, each lactiferous
duct is dilated to form lactiferous sinus,
before passing through the nipple.
• A sub-areolar lymphatic plexus of
Sappy collects the lymph from the
areola and nipple.

14. STRUCTURE OF THE BREAST
• It is made up of three components:
1. Glandular tissue: It is of tubulo-alveolar type and arranged in lobes
2. Fibrous tissue:
3. Interlobar fatty tissue

15. GLANDULAR TISSUE
• 15-20 pyramidal lobes, each drained
by a separate lactiferous duct
• Converges towards areola
• Lactiferous sinus
• Finally, ducts open on to the nipple.
• The ducts possess myo-epithelial cells

16. FIBROUS TISSUE
• Supports the lobes and forms a number
of septa which anchor the parenchyma
to overlying skin and the underlying
pectoral fascia.
• Suspensory ligaments of Cooper

17. INTERLOBAR FATTY TISSUE
• It makes the organ rounded in contour. Fat is however absent beneath the
areola and nipple.

21. STRUCTURAL DIFFERENTIATION

22. ARTERIAL SUPPLY OF BREAST
1. Lateral thoracic branch of axillary artery
provides lateral mammary branches – supply
the lateral part of the gland
2. Superior thoracic artery – upper part of gland
3. Perforating branches of internal thoracic artery
to the 2nd, 3rd and 4th intercostal spaces – form
the medial mammary branches – medial part
of breast
4. Lateral branches of 2nd, 3rd and 4th intercostal
arteries supply the deep surface of the gland.

23. VENOUS DRAINAGE OF BREAST
• The veins form a plexus, Circulus
Venosus beneath the areola.
• From this plexus the veins radiate
to the periphery in close
proximity to the skin and drain
into the axillary, internal thoracic
and intercostal veins.

24. VENOUS DRAINAGE OF BREAST
• Through the intercostal and azygous veins, the blood may
communicate via internal vertebral venous plexus (Batson) with intra-
cranial sagittal and transverse sinuses and establish venous
communications with clavicle, humerus and cervical vertebrae.
• Breast cancer may spread to these bones by the retrograde venous
flow.

25. NERVE SUPPLY OF BREAST
• The nerves are derived from the anterior and lateral cutaneous
branches of 4th to 6th intercostal nerves, which also convey
sympathetic fibers.

26. LYMPHATIC DRAINAGE OF BREAST
The lymphatic drainage is in two sets:
• Those draining the parenchyma of the breast including areola and
nipple
• Those draining the overlying skin excluding areola and nipple

27. From the parenchyma of the breast including
areola and nipple
• The lymph vessels form plexuses
in interlobular connective tissue
and walls of lactiferous ducts.
• These join with subareolar
plexus of Sappy (which collects
from areola and nipple)

28. DRAINAGE
1. 75 % of lymphatics from the gland drain into Axillary nodes. Efferents
from these nodes pass to Central group and thence to Apical group.
2. 20% of the lymphatics accompany the perforating branches of Internal
thoracic artery and drain into Parasternal (internal mammary) nodes
from both medial and lateral parts of breast.
3. 5% lymphatics from lateral and posterior parts of the gland follow the
posterior intercostal vessels and drain into Posterior Intercostal Nodes.

29. Draining the Overlying skin excluding areola
and nipple
• The integumental lymphatics, excluding areola
and nipple pass in radial manner and drain into
the following peripheral nodes:
1. From outer part : axillary nodes
2. From upper part: supraclavicular group of
lower deep cervical nodes. Some vessels reach
the cephalic nodes in delto-pectoral triangle
and drain into apical group of axillary nodes.
3. From inner part: parasternal nodes in relation
to Internal thoracic vessels in upper four to five
intercostal spaces.

30. Draining the Overlying skin excluding areola
and nipple
4. From lower part: these lymphatics communicate with those of
rectus sheath and form a sub-peritoneal plexus by piercing upper
part of linea alba. These drain into sub-diaphragmatic nodes and
finally reaches hepatic nodes around the bile duct.
4. Rarely, cancer cells from sub-peritoneal plexus drop into general
peritoneal cavity, undergo trans-coelomic migration and produce
secondary deposits on the surface of ovary forming Krukenberg’s
tumour.

31. CLINICAL CORRELATES
1. Skin incisions over breast
2. Fixation of tumour to the underlying pectoral fascia
3. Retraction of skin and nipple
4. Peau d’ orange
5. Congenital anomalies- ‘’thelia’’ and ‘’mastia’’
6. Lymphadenopathy
7. Krukenberg’s tumour
8. Breast examination

32. AXILLARY LYMPH NODES
• They are arranged into 5 groups
which lie in axillary fat :
• Pectoral (Anterior) group : which
lies on the pectoralis minor along
lateral thoracic vessels.
• Subscapular (Posterior) group :
which lies on posterior wall of
axilla on lower border of
subscapularis along subscapular
vessels.

33. AXILLARY LYMPH NODES
• Brachial (Lateral) group lies on lateral
wall of axilla along 3rd part of axillary
vessels.
• Central group : lies in axillary fat at the
base of axilla.
• Apical group : lies at apex of axilla.
• Subclavian lymph trunk: It is formed
by union of efferent lymph vessels of
apical group.
• It usually opens in subclavian vein. On
the left side it usually opens into
thoracic duct.

34. LYMPHATIC DRAINAGE
• Subareolar lymphatic
plexus :
• Lies beneath the areola.
• Deep lymphatic plexus:
• Lies on the deep fascia
covering pectoralis
major.
• Both plexuses radiate in
many directions and
drain into different
lymph nodes.

35. APPLIED ANATOMY- CANCER BREAST
• It is a common surgical condition.
• 60% of carcinomas of breast occur
in the upper lateral quadrant.
• 75% of lymph from the breast
drains into the axillary lymph
nodes.
• In case of carcinoma of one breast,
the other breast and the opposite
axillary lymph nodes are affected
because of the anastomosing
lymphatics between both breasts.

36. Applied Anatomy
• The lactiferous ducts
are radially arranged
from the nipple, so
incision of the gland
should be made in a
radial direction to
avoid cutting
through the ducts.
• Infiltration of the
ligaments of Cooper
by breast cancer
leads to its
shortening giving
peau de’orange
appearance of the
breast.

37. Mammary ridge
• Mammary ridge extends
from the axilla to the
inguinal region.
• In human, the ridge
disappears EXCEPT for a
small part in the
pectoral region.
• In animals, several
mammary glands are
formed along this ridge.

38. Skin /sebaceous gland

40. What is the difference

41. Axillary Lymph node
Axillary (ipsilateral): interpectoral (Rotter’s) nodes and lymph
nodes along the axillary vein and its tributaries that is divided
into the following levels:
a. Level I (low-axilla): lymph nodes lateral to the lateral border
of pectoralis minor muscle.
b. Level II (mid-axilla): lymph nodes between the medial and
lateral borders of the pectoralis minor muscle and the
interpectoral (Rotter’s) lymph nodes.
c. Level III (apical axilla): lymph nodes medial to the medial
margin of the pectoralis minor muscle and inferior to the clavicle.
These are also known as apical or infraclavicular nodes.

44. Sentinel node biopsy and axillary dissection
• Sentinel node biopsy is the most common way to check the axillary
lymph nodes for cancer.
• Before or during the procedure, a radioactive substance (called a
tracer) and/or a blue dye is injected into the breast. These substances
help the surgeon find the nodes to remove.
• The first lymph node(s) to absorb the tracer or dye is called the
sentinel node(s). This is also the first lymph node(s) where breast
cancer is likely to spread.

45. Sentinel node biopsy and axillary dissection
• The surgeon removes the sentinel node(s) to get it checked if the
node(s) contain cancer cells.
• If cancer is not found, it’s likely the other nodes do not contain
cancer. So, no more surgery is needed.
• If the node(s) do contain cancer, more lymph nodes may be removed,
which is called axillary dissection.

46. Lymphedema
• When lymph nodes are removed, some of the lymph vessels can
become blocked and cause lymphedema. Lymphedema is a build-up of
lymphatic fluid. It causes swelling in the arm or other areas such as the
hand, fingers, breast, chest or back.

47. Lymphedema
• Lymphedema isn’t common when only a few lymph nodes are
removed. The cases that do occur are less severe than when more
nodes are removed.
• Today, sentinel node biopsy is the preferred way to remove lymph
nodes (only a few nodes are removed). So, most people don’t get
lymphedema.