breast cancer pathology ( ref: bailey & love 26th edition ) -

BY :

ABDULLHA TASKIN ABDULBARI

4TH YEAR MEDICAL STUDENT – SULAIMAN ALRAJHEE COLLGES

NORMAL HISTOLOGY OF THE BREAST 2 cell types :–

line ducts lobules.

1. Contractile MYOEPITHELIAL CELLS lie on the BM assist in milk ejection during lactation & provides structural support to the lobules

2. EPITHELIAL CELLS Luminal –produce milk.

Epithelial & Myoepithelial cells lie on the basement membrane.

Breast cancer may arise from the epithelium of the duct system

• anywhere from the nipple end of the major lactiferous ducts to the terminal duct unit, which is in the breast lobule.

• The disease may be • in situ

• Or : invasive cancer.

• The degree of differentiation of the tumour is usually described using three grades:

• well differentiated,

• moderately differentiated or

• poorly differentiated.

• Ductal carcinoma is the most : common variant with lobular carcinoma

• occurring in up to 15 per cent of cases.

• There are sub- types of lobular cancer including:

• the classical type : which carries a better prognosis than

• the pleomorphic type.

• Occasionally, the picture may be mixed with both ductal and lobular features.

• immunohistochemical : analysis using the e-cadherin antibody, which reacts positively in lobular cancer, will help in diagnosis.

RARER HISTOLOGICAL VARIANTS

• colloid or mucinous carcinoma:

• whose cells produce abundant mucin,

• medullary carcinoma,

• with solid sheets of large cells often associated with a marked lymphocytic reaction,

• tubular carcinoma.

• Invasive lobular carcinoma is commonly multifocal and/or bilateral, hence the increasing use of MRI for assessment.

•

• Inflammatory carcinoma

• Rare

• highly aggressive cancer

• presents as a :

• painful, swollen breast, which is warm with cutaneous oedema.

• This is the result of :

• blockage of the subdermal lymphatics with carcinoma cells.

• Inflammatory cancer : usually involves at least one-third of the breast and may mimic a breast abscess.

• A biopsy : will confirm the diagnosis and show undifferentiated carcinoma cells.

In situ carcinoma :

• is prei-nvasive cancer that has

• not breached the epithelial basement membrane.

• usually : asymptomatic, finding in breast biopsy specimens

• > 20 % of cancers detected by screening in the UK.

• In situ carcinoma may be:

• ductal (DCIS) or

• lobular (LCIS), the latter often being multi-focal and bilateral.

• Both are markers for the later development of invasive cancer,

• which will develop in at least 20 per cent of patients.

• mastectomy : is curative !!

DCIS may be classified using, the Van Nuys system

• which combines the patient’s :

• age, type of DCIS and presence of microcalcifica-tion, extent of resection margin and size of disease.

• Patients with a high score : benefit from radiotherapy after excision,

• low grade : whose tumour is completely excised, need no further treatment.

Staining for oestrogen and progesterone receptors :

• now considered routine,

• their presence :

• Rx : adjuvant hormonal therapy with tamoxifen or an aromatase inhibitor

Staining for c-erbB2 (also known as HER-2/neu) :

• positive > Rx > : monoclonal antibody trastuzumab (Herceptin®),

Paget’s disease of the nipple :

• is a superficial manifestation of an underlying breast carcinoma.

• It presents as :

• an eczema-like condition of the nipple and areola, which persists despite local treatment.

• The nipple is eroded slowly and eventually disappears.

• If left, : the underlying carcinoma will sooner or later become clinically evident

• nipple eczema : should be biopsied if there is any doubt about its cause.

• Microscopically:

• characterised by : the presence of :

• large, ovoid cells with abundant, clear, palstaining cytoplasm

• in the Malpighian layer of the epidermis.

The spread of breast cancer :

•Local

•Lymphatic

•Blood stream

Local spread :

• The tumour increases in size

• and invades other portions of the breast.

• It tends to involve : skin , pectoral muscles and chest wall.

Lymphatic metastasis :

• primarily : to the axillary and the internal mammary lymph nodes.

• Tumours in the posterior one-third of the breast are to drain to :

• the internal mammary nodes.

• It represents :

• the spread of the carcinoma .

• marker for the metastatic potential of that tumour.

LYMPHATIC DRAINAGE

OF BREAST

Spread by the bloodstream :

• It is by this route that skeletal metastases occur :

• the lumbar vertebrae, femur, thoracic vertebrae, rib and skull are affected

• these deposits are generally osteolytic.

• Metastases may also commonly occur in :

• the liver, lungs and brain and, the adrenal glands and ovaries.