This document summarizes the anatomy and embryological development of the breast. It describes how the breast develops from mammary ridges in the embryo and can have accessory breasts or nipples from failed regression. The blood supply, innervation, and lymphatic drainage of the breast is outlined. Infectious disorders of the breast are also summarized, including bacterial infections commonly caused by Staphylococcus aureus and Streptococcus in the postpartum period. Treatment involves antibiotics and may require surgical drainage for abscesses.

1. BREAST

2. ANATOMY:
Embryology
• At Week 5-6 of fetal development, two ventral bands of thickened ectoderm mammary ridges & milk
lines
• In most mammals, paired breasts develop along these ridges, which extend from the base of the
forelimb (future axilla) to the region of the hind limb (inguinal area). These ridges are not prominent in the
human embryo and disappear after a short time, except for small portions that may persist in the pectoral
region.
• Accessory breasts (polymastia) or accessory nipples (polythelia) may occur along the milk line when
normal regression fails.
• Accessory nipples (polythelia) occur in <1% of infants and may be associated with abnormalities of the
urinary and cardiovascular systems.

3. • Symmastia is a rare anomaly recognized as webbing between the breasts across the
midline.
• Turner’s syndrome (ovarian agenesis and dysgenesis) and Fleischer’s syndrome
(displacement of the nipples and bilateral renal hypoplasia) may have polymastia as a
component.
• Absence of the breast (amastia) is rare and results from an arrest in mammary ridge
development that occurs during the sixth fetal week.
• Poland’s syndrome: hypoplasia or complete absence of the breast, costal cartilage and rib
defects, hypoplasia of the subcutaneous tissues of the chest wall, and brachy-syndactyly.

4. Functional Anatomy
• The breast is composed of 15 to 20 lobes which are each composed of several lobules.
• Fibrous bands of connective tissue travel through the breast (Cooper’s suspensory ligaments), insert
perpendicularly into the dermis, and provide structural support.
• The mature female breast extends from the level of the second or third rib to the inframammary fold
at the sixth or seventh rib. It extends transversely from the lateral border of the sternum to the
anterior axillary line.
• The deep or posterior surface of the breast rests on the fascia of the pectoralis major, serratus
anterior, and external oblique abdominal muscles, and the upper extent of the rectus sheath.
• The retromammary bursa: on the posterior aspect of the breast between the investing fascia of the
breast and the fascia of the pectoralis major muscles.
• The axillary tail of Spence extends laterally across the anterior axillary fold.
• The upper outer quadrant of the breast contains a greater volume of tissue than do the other quadrants.

5. Nipple-Areola Complex.
• The epidermis of the nipple-areola complex is pigmented and is variably corrugated. During
puberty, the pigment becomes darker and the nipple assumes an elevated configuration.
Throughout pregnancy, the areola enlarges and pigmentation is further enhanced.
• The areola contains sebaceous glands, sweat glands, and accessory glands, which produce small
elevations on the surface of the areola (Montgomery’s tubercles).
• Smooth muscle bundle fibres , which lie circumferentially in the dense connective tissue and
longitudinally along the major ducts, extend upward into the nipple, where they are responsible for
the nipple erection that occurs with various sensory stimuli.
• The dermal papilla at the tip of the nipple contains numerous sensory nerve endings and
Meissner’s corpuscles. This rich sensory innervation is of functional importance because the
sucking of the infant initiates a chain of neurohumoral events that results in milk let down

6. Blood Supply, Innervation, and Lymphatics
Principal blood supply from:
(a) perforating branches of the internal mammary artery;
(b) lateral branches of the posterior intercostal arteries; and
(c) branches from the axillary artery, including the highest thoracic, lateral thoracic, and pectoral
branches of the thoraco acromial artery
• The second, third, and fourth anterior intercostal perforators and branches of the internal mammary
artery arborize in the breast as the medial mammary arteries.
• The lateral thoracic artery gives off branches to the serratus anterior, pectoralis major and pectoralis
minor, and subscapularis muscles. It also gives rise to lateral mammary branches.

7. The veins of the breast and chest wall follow the course of the arteries,
with venous drainage being toward the axilla.
The three principal groups of veins are
(a) Perforating branches of the internal thoracic vein,
(b) Perforating branches of the posterior intercostal veins, and
(c) tributaries of the axillary vein.
• Batson’s vertebral venous plexus, which invests the vertebrae and
extends from the base of the skull to the sacrum,may provide a route
for breast cancer metastases to the vertebrae,skull, pelvic bones, and
central nervous system.

8. Nerve supply:
• Lateral cutaneous branches of the third to sixth intercostal nerves
breast (lateral mammary branches) and of the anterolateral chest wall.
• Cutaneous branches from the cervical plexus, specifically the anterior
branches of the supraclavicular nerveskin over the upper portion of the
breast.
• The intercostobrachial nerve [lateral cutaneous branch of the second
intercostal nerve]
visualized during surgical dissection of the axilla.
Resection of theintercostobrachial nerve causes loss of sensation over the
medial aspect of the upper arm.

9. lymph drainage of the axilla
The plexus of lymph vessels in the breast arises in the interlobular connective tissue and
in the walls of the lactiferous ducts and communicates with the subareolar plexus of
lymph vessels.
Efferent lymph vessels from the breast pass around the lateral edge of the pectoralis
major muscle and pierce the clavipectoral fascia, ending in the external mammary
(anterior, pectoral) group of lymph nodes.
Some lymph vessels may travel directly to the subscapular (posterior,scapular) group of
lymph nodes.
From the upper part of thebreast, a few lymph vessels pass directly to the subclavicular
(apical)group of lymph nodes.
The six axillary lymph node
(a) the axillary vein group (lateral)
• four to six lymph nodes
• lie medial or posterior to the vein and
• receive most of the lymph drainage from the upper extremity

10. (b) the external mammary group (anterior or pectoral group)
• five to six lymph nodes
• lie along the lower border of the pectoralis minor muscle contiguous with the lateral thoracic vessels and
• receive most of the lymph drainage from the lateralaspect of the breast;
(c) the scapular group (posterior orsubscapular), which consists of
• five to seven lymph nodes that
• lie along the posterior wall of the axilla at the lateral border of the scapula.
• Receive lymph drainage principally from the lower posterior neck, the posterior trunk, and the posterior
shoulder
(d) the central group
• three or four sets of lymph nodes that are
• embedded in the fat of the axilla lying immediately posterior tothe pectoralis minor muscle
• receive lymph drainage bothfrom the axillary vein, external mammary, and scapular groups of lymph nodes,
and directly from the breast;

11. (e) the subclavicular group (apical)
• six to twelve sets of lymph nodes
• lie posterior and superior to the upper border of the pectoralis minor muscle
• receive lymph drainage from all of the other groups of axillary lymph nodes
(f) The interpectoral group (Rotter’s lymph nodes)
• one to four lymph nodes that are
• interposed between the pectoralis major and pectoralis minor muscles and
• The lymph fluid that passes through the interpectoral group of lymph nodes passes directly into the
central and subclavicular groups.

12. • The axillary lymph nodes --receive >75% of the lymph drainage
from the breast.
• The rest is derived primarily from the medial aspect of the breast,
flows through the lymph vessels that accompany the
perforatingbranches of the internal mammary artery, and enters the
parasternal (internal mammary) group of lymph nodes.
• Axillary lymph node groups

13. INFECTIOUS AND INFLAMMATORY DISORDERS
OF THE BREAST
• Infections in the postpartum period remain proportionately the most common time for breast infections to
occur.
Bacterial Infection
• Staphylococcus aureus and Streptococcus species - most frequent organisms.
• Typically breast abscesses are seen in staphylococcal infections and present with point tenderness,erythema,
and hyperthermia.
If related to lactation they usually occur within the first few weeks of breastfeeding.
On progression of a staphylococcal infection -result in subcutaneous, subareolar, interlobular(periductal), and
retromammary abscesses (unicentric or multicentric).
• now the initial approach is antibiotics
• Operative drainage is now reserved for those cases that do not resolve with repeated aspiration and antibiotic
therapy
or
cases in which there is some other indication for incision and drainage (e.g., thinning or necrosis of theoverlying
skin).

14. • While staphylococcal infections tend to be more localized and may be
situated deep in the breast tissues, streptococcal infections usually
present with diffuse superficial involvement. They are treated with
local wound care, including application of warm compresses, and the
administration of IV antibiotics (penicillins or cephalosporins).
Epidemic puerperal mastitis
• initiated by highly virulent strains of methicillin-resistant S aureus that
are transmitted via the suckling neonate.
• Purulent fluid maybe expressed from the nipple. In this circumstance,
breast feeding is stopped, antibiotics are started, and surgical therapy
is initiated.

15. Nonepidemic (sporadic) puerperal mastitis
• involvement of the interlobular connective tissue of the breast by an infectious process.
• develops nipple fissuring and milk stasis, which initiates a retrograde bacterial infection.
• Emptying of the breast using breast suction pumps shortens the duration of symptoms
and reduces the incidence of recurrences.
• The addition of antibiotic therapy results in a satisfactory outcome in >95% of cases.
Zuska’s disease [recurrent periductal mastitis]
• a condition of recurrent retroareolar infections and abscesses
• Smoking ---a risk factor
• managed symptomatically by antibiotics coupled with incision and drainage
• wide debridement of chronically infected tissue and/or terminal duct resectioncurative

16. Mycotic Infections
a)Blastomycosis or sporotrichosis
• Intraoral fungi that are inoculated into the breast tissue by the suckling infant -mammary abscesses in close
proximity to the nipple-areola complex.
• Pus mixed with blood may be expressed from sinus tracts.
• Antifungal agents treatment of systemic (noncutaneous) infections.
• Occasionallydrainage of an abscess, or even partial mastectomyto eradicate a persistent fungal infection.
b)Candida albicans
• erythematous, scaly lesions of the inframammaryor axillary folds.
• Scrapings from the lesions --fungal elements (filaments and binding cells).
• Therapy- topical application of nystatin.
Hidradenitis Suppurativa of the nipple-areola complex or axilla
• a chronic inflammatory condition that originates within the accessory areolar glands of Montgomery or within
the axillary sebaceous glands.
• chronic acne predisposed to developing hidradenitis.
• Antibiotic therapy with incision and drainage of fluctuant areas is appropriate treatment.

18. COMMON BENIGN DISORDERS AND DISEASES OF
THE BREAST

22. INVESTIGATIONS OF BREAST DISEASE:

23. BIRADS:

28. BREAST CARCINOMA

30. RISK ASSESSMENT IN BREAST CANCER :
1. GAIL MODEL
2. CLAUSS MODEL
3. BRACPRO MODEL
4. TYRER-CUZIK MODEL

33. DIAGNOSIS OF BREAST CANCER
• In ∼30% of cases, the woman discovers a lump in her breast.
• Other less frequent presenting signs and symptoms of breast cancer include:
(a) breast enlargement or asymmetry;
(b) Nipple changes, retraction, or discharge;
(c) ulceration or erythema of the skin of the breast;
(d) an axillary mass; and
(e) musculo-skeletal discomfort.
• However, up to 50% of women presenting with breast complaints have no physical signs of breast
pathology.
• Breast pain usually is associated with benign disease.
• If a young woman (≤45 years) presents with a palpable breast mass and equivocal mammographic
findings, ultrasound examination and biopsy are used to avoid a delayin diagnosis.

34. Examination Inspection Palpation
 Imaging Techniques
• Mammography
• Ultrasonography.
• Magnetic Resonance Imaging
Breast Biopsy
• Nonpalpable Lesions. Image-guided breast biopsy specimens are
frequently required to diagnose nonpalpable lesions.
Ultrasound localization techniques are used when a mass ispresent,
whereas stereotactic techniques are used when no mass is present
(microcalcifications or architectural distortion only).
• Palpable Lesions. FNA or core biopsy of a palpable breast mass can usually
be performed in an outpatient setting.

35. BREAST CANCER STAGING AND BIOMARKERS
Breast Cancer Staging:

36. Biomarkers [IHC]
a) Steroid Hormone Receptor Pathway:
• determination of estrogen and progesterone receptor status
• Tumors positive for estrogen or progesterone receptors have a higher response rate to endocrine therapy
(b) growth factors and growth factor receptors-human epidermal growth factor receptor 2 (HER2)/neu,
epidermal growth factor receptor (EGFR), transforming growth factor, platelet-derived growth factor, and
the insulinlikegrowth factor family;
• HER2/Neu +VE: INVASIVE, METASTATIC, EARLY LN INVOLVEMENT, INCREASE RISK OF RECURRENCE AND
DECREASE SURVIVAL RATE
(c) indices of proliferation --proliferating cell nuclear antigen (PCNA) and Ki-67 - HIGH NUCLEAR GRADE
TUMOUR, ER-VE TUMOUR

37. (d) Indices of angiogenesis such as vascular endothelial growth factor(VEGF) and the angiogenesis
index---- INCREASE MICROVASCULAR DENSITY: INVASIVE CARCINOMA
(e) the mammalian target of rapamycin (mTOR) signaling pathway;
(f) tumor-suppressorgenes such as p53;
(g) the cell cycle, cyclins, and cyclin-dependent kinases;
(h) the proteasome;
(i) the COX-2 enzyme;
(j) The peroxisome proliferator-activated receptors (PPARs); and
(k)indices of apoptosis and apoptosis modulators such as bcl-2and the bax:bcl-2 ratio -->inhibit
apoptosis: high histologic grade tumour, LN +VE, poor response to chemotherapy, decrease survival.

38. MANAGEMENT::
In Situ Breast Cancer (Stage 0)
LCIS : observation, chemoprevention, and bilateral total mastectomy.
DCIS with
evidence of extensive disease (>4 cm of disease or disease in more than one
quadrant) -------------mastectomy
For women with limited disease -----lumpectomy and radiation therapy
For non palpable DCIS, needle localization or other image-guided techniques are
used to guide the surgical resection. Specimen mammography is performed to
ensure that all visible evidence of cancer is excised.
Adjuvant tamoxifen therapy is considered for DCIS patients with ER-positive
disease.
The gold standard against which breast conservation therapy for DCIS is
evaluated is mastectomy.

39. Early Invasive Breast Cancer(Stage I, IIA, or IIB)
Mastectomy + Axillary LN status assessment or [ BCT + RT ]+ Axillary LN status assessment
• If sentinel LN can not be identified or found to harbor metastatic disease, axillary LN dissection (Level I+II)
should be done.
Indications of Adjuvant Chemotherapy
1. LN positive
2. Tumor>1 cm
3. LN negative, >0.5 cm with adverse prognostic factors:
• Blood vessel or lymph vessel invasion
• High nuclear or histologic grade
• Her-2-neu over expression
• Negative hormone receptor status
 Endocrine therapy:
• Tamoxifene should be given for hormone receptor positive, cancer >1 cm
• Trastazumab should be given for Her-2-neu positive cancer

40. Locally Advanced Breast Cancer (Stage IIIA, IIIB, IIIC):
• Neoadjuvant chemotherapy + MRM + Adjuvant RT
• BCT for IIIA with N1 with patients who achieve good response to neoadjuvant
chemotherapy
• Systemic chemotherapy + radiotherapy are indicated in treatment of grossly
involved internal mammary nodes (N3b)

41. Distant Metastases (Stage IV):
Indications of Hormonal Therapy
1. Hormone receptor positive
(ER/PR positive)
2. Bone or soft tissue metastases
only
3. Limited or asymptomatic
visceral metastases
Treatment for stage IV breast cancer is not curative but may
• Prolong survival and improve quality of life
• Hormonal therapies are preferred to cytotoxic therapy as it is associated with minimal toxicity
Indications of Systemic Chemotherapy
1. Hormone receptor negative
2. Hormone refractory (after 3
endocrine regimens)
3. Symptomatic visceral metastases

42. • Women with stage IV breast cancer-----develop anatomically
localized problems that will benefit from individualized surgical or
radiation treatment , such as brain metastases, pleural effusion,
pericardial effusion,biliary obstruction, ureteral obstruction,
impending or existing pathologic fracture of a long bone, spinal cord
compression, and painful bone or soft tissue metastases.
• Bisphosphonates or anti-RANKL agent, denosumab + chemotherapy
or endocrine therapy--bone metastases.
• surgical resection of the local-regional disease in women with stage
IV breast-----------women who undergo resection of the primary
tumor have improved survival over those who do not.

43. OVERALL:
Local Regional Recurrence
• Who had mastectomy: Resection of local regional recurrence with reconstruction
+ chemotherapy + hormonal therapy + RT (if not received RT previously)
• Who had lumpectomy: Mastectomy with reconstruction + chemotherapy +
hormonal therapy

46. Chemotherapy in CA Breast
• Most popular combinations--CMF & CAF
(Cyclophosphamide, Adriamycin
[doxorubicin], and 5-fluorouracil
• CMF is no longer considered adequate
adjuvant chemotherapy
• Modern regimens include an anthracycline
(doxorubicin or epirubicin) and taxanes.
• Effect of combining hormone &
chemotherapy is additive although hormone
therapy is started after completion of
chemotherapy to reduce side-effects.
Indications of Radiotherapy in
Carcinoma Breast
• Locally Advanced Breast Cancer (to
decrease recurrence rate)
• After breast conservation surgery
• Margin is positive after mastectomy
• Metastases to 4 or more lymph nodes

47. Hormonal Therapy in Carcinoma Breast
1. Ovarian suppression or ablation: − Bilateral oophorectomy
− Medically by LHRH agonist (Goserelin, Leuperolide)
2. SERM: Tamoxifen and Raloxifene
3. Aromatase lnhibitors: − Non-steroidal: Letrozole and Anastrazole
− Steroidal: Exmestane
4. Anti-estrogens: Fulvestrant
5. Progestins: Megesterol& Medroxyprogesterone acetate.
• Tamoxifen is DOC in premenopausal patients
• Aromatase inhibitors are DOC in postmenopausal patients

48. New Drugs in CA Breast
Ixabepilone -------Used for antracycline&taxane resistant breast cancer
Lapatinib -------Inhibitor of Her-2-neu & EGFR tyrosine kinase
--Second line Her-2-neu therapy
Sunitinib ---------refractory metastatic breast cancer
TARGETTED THERAPY:
ANGIOGENESIS INHIBITOR: VEGFi: BEVACIZUMAB
PARP INHIBITOR: INIPARIB, OLAPARIB,VELIPARIB
MTORi: rapamycin, everolimus
PD-L1: ATEZOLIZUMAB, PEMBROLIZUMAB

50. Paget’s Disease of Nipple
• Chronic eczematous eruption of nipple which may progress to an ulcerated weeping
lesion.
• CEA positivity
Histopathology
• Paget cell is large, pale staining with round nuclei & large nucleoli
• Paget cells does not invade dermal basement membrane(carcinoma in
situ)
Clinical Features
• >97% underlying ductal carcinoma (in situ or invasive)
• may (54%) or may not (46%) be accompanied by a mass

51. Diagnosis
• Complete mammography and biopsy is required to rule out occult
multicentric disease
• Biopsy showing Paget cell is diagnostic
Treatment
• Most commonly utilized procedure is simple mastectomy
• Wide excision of nipple and areola to achieve clear ,margins +
Radiotherapy + Axillary staging
• Lumpectomy + Radiotherapy + Axillary LN dissection

52. Sentinel Lymph Node Dissection
INDICATIONS: accurate for staging of the axilla in
1. primarily used to assess the regional lymph nodes in women with early breast cancers who are
clinically node-negative by physical examination and imaging studies.
2. larger tumors (T3 N0)
3. after chemotherapy in women with clinically node-negative disease at initial presentation.
Not recommended in patients with
1. inflammatory breast cancers,
2. those with biopsy proven metastasis,
3. DCIS without mastectomy
4. prior axillary surgery.
• PROCEDURE: combination of intra-operative gamma probe detection of radioactive colloid and
intraoperative visualization of blue dye (isosulfan blue dye or methylene blue).
• safe in pregnancy when performed with radioisotope alone.

53. LONG QUESTIONS BASED ON THE TOPIC:
1. Describe surgical anatomy of breast.
2. Lymphatic drainage of of breast and its surgical importance.
3. Discuss benign breast disorder and outline their management.
4. Management of early breast cancer [EBC].
5. Management of locally advanced breast cancer [LABC].
6. Indications and contraindications of BCS.
7. Discuss paget’s disease of nipple.
8. Discuss SLNB and its significance.

54. 1. Dose of radiation per study in mammography:
• a. 0.1cGy b. 0.2 c. 0.3 d. 0.4
2. BIRADS stands for:
a. Breast Imaging Reporting and Data System
b. Best Imaging Reporting and Data System
c. Brain Imaging Reporting and Data System
d. Best Imaging Reporting and Data System

55. ANSWER::
1. Dose of radiation per study in mammography:
• a. 0.1cGy b. 0.2 c. 0.3 d. 0.4
2. BIRADS stands for:
a. Breast Imaging Reporting and Data System
b. Best Imaging Reporting and Data System
c. Brain Imaging Reporting and Data System
d. Best Imaging Reporting and Data System

56. 3. A 45-year-old female presented to your OPD with this lesion in the
left breast. What is the most probable diagnosis?
a. DCIS b. LCIS c. Peau-d’orange d. Paget’s disease of nipple

57. ANSWER:::
3. A 45-year-old female presented to your OPD with this lesion in the
left breast. What is the most probable diagnosis?
a. DCIS b. LCIS c. Peau-d’orange d. Paget’s disease of nipple

58. 4. A 43-year-old lady presents with a 5cm lump in right breast with a
3cm node in the supraclavicular fossa. Which of the following TNM
stage she belongs to as per the latest AJCC staging system?
• a. T2N0M1 b. T1N0M1 c. T2N3M0 d. T2N2M0
5.Breast conservation surgery indicated in:
a. Tumor size < 4 cm b. Central
c. Mobile d. Pendulous breast
e. Diffuse microcalcification

59. ANSWER::::
4. A 43-year-old lady presents with a 5cm lump in right breast with a
3cm node in the supraclavicular fossa. Which of the following TNM
stage she belongs to as per the latest AJCC staging system?
• a. T2N0M1 b. T1N0M1 c. T2N3M0 d. T2N2M0
5.Breast conservation surgery indicated in:
a. Tumor size < 4 cm b. Central
c. Mobile d. Pendulous breast
e. Diffuse microcalcification

60. 6. Aromatase inhibitors used in CA breast are:
a. Letrozole b. Anastrozole
c. Exemestane d. Tamoxifen
7. In Patey’s modified mastectomy, which of the following is
preserved?
a. Intercostobrachial nerve b. Pectoralis major
c. Pectoralis minor d. Axillary fascia

61. ANSWER::
6. Aromatase inhibitors used in CA breast are:
a. Letrozole b. Anastrozole
c. Exemestane d. Tamoxifen
7. In Patey’s modified mastectomy, which of the following is
preserved?
a. Intercostobrachial nerve b. Pectoralis major
c. Pectoralis minor d. Axillary fascia

62. 8.Mondor’s disease is superficial thrombophlebitis of:
a. Axillary vein b. Long saphenous vein
c. Veins of the breast d. Internal mammary vein
9. A 50 years old female presented with the given tumor in the OPD.
The tumor was found to be malignant on biopsy. What is the best
treatment option?
a. Breast conservation surgery
b. Simple mastectomy
c. Wide local excision
d. Modified radical mastectomy

63. ANSWERS::
8.Mondor’s disease is superficial thrombophlebitis of:
a. Axillary vein b. Long saphenous vein
c. Veins of the breast d. Internal mammary vein
9. A 50 years old female presented with the given tumor in the OPD.
The tumor was found to be malignant on biopsy. What is the best
treatment option?
a. Breast conservation surgery
b. Simple mastectomy
c. Wide local excision
d. Modified radical mastectomy