CLASSIFICATION OF TUMOURS

transcript

CLASSIFICATION OF

TUMOURS

Dr Mohamed Elkablawy

ناقص مالحظةالصور اضافة

Neoplasia 2

CLASSIFICATION OF TUMOURS

Intended Learning outcomes

By the end of this talk you should

•Be aware of the calssification of tumours

•Know how tumours are named

•Be familiar with the differences between

benign and malignant tumours

•Know how malignant tumours spread

Calssification Of Tumours

Usually on basis of presumed cell/tissue of origin

On predicted behaviour

Calssification Of Malignant Tumours

Usually on basis of cell/tissue of origin

Main groups are:

•Epithelial

•Connective tissue (mesenchymal)

•Lymphoid/haematological

•Mixture of all (teratomas)

Nomenclature

Tissue of origin

Epithelial:

• cell of origin benign malignant

•Squamous cell Papilloma Sq C carcinoma

•Glandular Adenoma Adenocarcinoma

•Transitional TC Papilloma T C carcinoma

•Basal BC Papilloma B C carcinoma

Nomenclature

Tissue of origin

Mesenchymal:• cell of origin benign malignant

•Smooth Muscle Leiomyoma Leiomyosarcoma

•Striated Muscle Rhabdomyoma Rhabdomyosarcoma

•Blood Vs Heam(angioma) Angiosarcoma

•Nerves Neurofibroma Neurofibrosarcoma

•Adepose tissue Lipoma Liposarcoma

•Cartilage Chondroma Chondrosarcoma

•Bone Osteoma Osteosarcoma

CLASSIFICATION OF TUMOURSNomenclature

Tissue of origin

Mesenchymal:

• cell of origin benign malignant

•Lymphoid Lymphoma

•Hemopoietic Leukemia

•Melanocytes Neavus Melanoma

•Embryonic tisue

•Totipotential cells Teratoma Malignant teratoma

•Unipotential cells Retinoblastoma

Nephroblastoma

Benign Tumours

• Generally slow growing

•Remain localised

•Do not invade surrounding tissues

•Do not spread to distant sites

•Resemble tissue of origin i.e. Well

differentiated

CLASSIFICATION OF TUMOURSBenign Tumours (Microscopic)

• Mitotic activity is low

•Mitotic figures appear normal

•Nuclei appear normal

•No necrosis

CLASSIFICATION OF TUMOURS Benign Tumours (Effects)

• May be unsightly, removed for cosmotic

purposes

•Damage tissue by pressure effects

•Block ducts such as a pancreas or

bronchus

•Block flow of fluid in brain

•May secrete hormones

•May become malignant

Malignant Tumours

• Generally rapid growing

•Irregular edges poorly defined margins

•Invade surrounding tissues

•Spread to distant sites

•May not resemble tissue of origin i.e.

poorly differentiated or anaplastic

CLASSIFICATION OF TUMOURSMalignant Tumours (Microscopic)

• Mitotic activity is high

•Abnormal Mitotic figures

•Nuclei are hyperchromatic and

pleomorphic

•Necrosis usually occur

Malignant Tumours (Spread)

• Invade surrounding tissues

•Spread via lymphatic channels to lymph

•Spread via blood stream to other organs

i.e. metastasis

•Spread across body cavities

Malignant Tumours - Effects

• Destruction of adjacent tissues causing

pain and loss of function

•Pressure on structures leading to

necrosis and infection

•Haemorrhage from surface ulceration

•Obstruction of flow through vital

structures

Malignant Tumours - Effects

• Secondary deposits (metastasis) causing

damage at distant sites

•Cachexia (wasting) due to tumour

necrosis factor-α

•Production of hormones either

appropriate or inappropriate (ectopic)

•Paraneoplastic syndromes

carcinoma of breast. This is not a specific histologic type of breast cancer, but rather

it implies dermal lymphatic invasion by some type of underlying breast carcinoma.

Such involvement of dermal lymphatics gives the grossly thickened,

erythematous, and rough skin surface with the appearance of an orange peel

("peau d'orange"). BACK

Malignant Tumours - Metastasis

• Process by which neoplastic cells from

primary tumour spread to distant sites.

•Involves primary tumour invation into

surrounding tissues, specially vessels

(lymphatic or blood)

•Then detachment within vessels and

transport as emboli

• Extravasation (move from vessel to

tissue) and growth at distant sites

•Lymphatic spread leads to lymph node

involvement

• Blood vessel spread leads to

haematogenous metastasis (liver, lung,

bone and brain)

•Less commonly, transcoelomic spread

occurs (across body cavities)

Malignant Tumours

Stage/Grade of tumours

• GRADE refers to how closely tumours

resemble their tissue of origin

•STAGE refers to how far a tumour has

spread at the time of presentation

Malignant Tumours

Stage/Grade of tumours• Different systems exist for different tumours

•Dukes’ stage predicts prognosis for colorectal

tumours

•Duke’s A: 90% 5yrs, continued to bowel wall

•Duke’s B: 66% 5yrs, outside bowel wall, LN -ve

•Duke’s C: 33% 5yrs, LN +ve

Malignant Tumours

Stage/Grade of tumours

TNM system• T : Primary tumour size

•N : Lymph Node involvement

•M : Distant metastasis

•Different TNM for each different organ and

tumour

Breast Blood + Lymphatic Supply

• Arterial:

• Anterior perforating branches of internal

mammary artery (internal thoracic)

• Branches of external mammary artery (lateral

thoracic)

• Venous:

• Axillary vein

• Internal thoracic vein

Breast Blood + Lymphatic Supply

• Lymphatic:

• 75% To ipsilateral axillary lymph nodes

• Central

• Pectoral

• Subscapular

• Remainder to infra/supraclavicular and

parasternal lymph nodes, and to contralateral

breast

Breast Histology

Breast Histology (lobules)

Duct Carcinoma In Situ (DCIS)

• Aka intaduct carcinoma

• Tumour cells confined to ducts and acini – no

evidence of any invation of surrounding stromal

tissue

• Tumour cells therefore have no access to

lymphatics or blood vessels

• Approximately 3 – 5% cancers in symptomatic

series and Up to 25% in screening series

• Clinical presentations: mass, nipple discharge,

paget’s disease.

• Mammographic presentation: microcalcification

Duct Carcinoma In Situ (DCIS)

Breast Cancer

• Second most common cancer after lung

• 10.4% of all cancer incidence

• Commonly arises in lobules or ducts

• Can present with symptoms e.g. lump,

lymphadenopathy, nipple discharge

• Can be identified on screening e.g. mammogram

• Requires triple assessment

• 1. Clinical examination

• 2. Radiology (mammogram, Ultrasound)

• 3. Tissue diagnosis (FANC, core biopsy, excisional

biopsy)

Br Ca Macroscopic Appearance

Br Ca Lymph Nodes

• Historically, large groups were removed

Side effects: lymphoedema

• Sentinel lymph node mapping

- Examines first node(s) to drain tumour

for evidence of malignancy

- Identify with dye & radiation

- Can prevent 65 – 70% of patients having

unnecessary axillary node clearance

صورة

Invasive Carcinomas

• Invasive duct carcinoma (carcinoma of no special

type [NST]

• Invasive lobular carcinoma

• Tubular carcinoma

• Mucinous carcinoma

• Medullary (like) carcinoma

• Metaplastic carcinoma

• Rarities

Ductal, NST

• Commonest up to 75%

• Contains <50% of special type characteristics

• Wide variety of histological appearances

Vertebral metastasis

Liver metastasis

Tumour staging

• Based on degree of tumour spread

• TNM classification

• T – local spread – size, involvement of local

structures e.g. skin, chest wall

• N – Nodes – axillary (IPSL – and contralateral),

internal mammary, supraclavicular. Number and

size (very complicated)

• M – distant metastasis

Stage grouping

• Grouped into stage 0 – stage IV according to TNM

classification

• Eg. Stage 1 – T1,N0,M0

• Stage IV – M1, any T and N

• Useful for clinical trials

Prognostic indicators

• Lymph node stage

• Tumour size

• Tumour grade

• Tumour type

• Lymphovascular invasion

• (extensive DCIS at margins)

• (Margin clearance)

Surgery

• Treatment depends on stage

• Surgery is the mainstay

• Clear margins important

• 1. Wide local excision (lumpectomy/ breast

conservative therapy)

• 2. Mastectomy if

• Multi-focal tumours

• Previous radiotherapy to breast

• Tumour large relative to breast

• Patient preference

Other treatments• Radiotherapy

• - Reduces risk of local recurrence

• Chemotherapy

• - Systemic treatment, more advanced disease

• Hormone Therapy

- Depending on ER/PR expression

- Tamoxifen (ER antagonist)

- Aromatase inhibitors (block oestrogen production)

• Monoclonal antibodies

• -Herceptin (HER2/neu receptor antagonist)

Intended Learning outcomes

By now you should

•Be aware of the calssification of tumours

•Know how tumours are named

•Be familiar with the differences between

benign and malignant tumours

•Know how malignant tumours spread

Breast Carcinoma

The most common malignancy in women

In UK 1 in 10-12 chances 1 in 8 women in US Less incidence in Asia Majority of cancers arise

in the ducts. Very rare before age 25

Normal Breast

Large ductLobules

Normal Breast

A normal breast acinus. Note the epithelial cells lining the lumen demonstrate apocrine secretion with

snouting, or cytoplasmic extrusions, into the lumen.

Comparison of the gross characteristics of a classic infiltrating ductal carcinoma on the left and a benign fibroadenoma on the right

Crab like shapedue to lines of infiltration

Infiltrating Duct Carcinoma

Prominent bands of collagen

Tendcy to form ductal strucures

Invasive Lobular CarcinomIndian File Strands

Infiltrating Duct CarcinomaLocal Spread

Retraction of nipple

Fixation to underlying muscle

Here is a surgical excision of a small mass from the breast. The mass is well-

circumscribed. Grossly it felt firm and rubbery. This is a fibroadenoma. The blue dye

around the fibroadenoma was used to mark the lesion during needle localization in

radiology so that the surgeon could find this small mass.

Here is the microscopic appearance of a fibroadenoma. To the right is compressed breast connective tissue

forming a "capsule" to this mass. The neoplasm itself is composed of a fibroblastic stroma in which are located elongated compressed ducts lined by benign appearing

epithelium

This is the gross appearance of fibrocystic changes in the breast. A 1.5 cm cyst is noted here. This can lead to palpation of an ill-defined "lump" in the

breast. Sometimes, fibrocystic changes produce a more diffusely lumpy breast.

Another example of microscopic fibrocystic changes of the breast are shown here. Fibrocystic changes

account for the majority of "breast lumps" that are found in women of reproductive years, particularly

between age 30 and menopause.

This is the histologic appearance of fibrocystic changes in breast. There are cystically dilated ducts, areas of

lobules that are laced with abundant fibrous connective tissue (sclerosing adenosis), and stromal fibrosis. There is even a small area of microcalcification seen just to

the upper right of center. No atypical changes are seen here

Prominent sclerosing adenosis, one of the features of fibrocystic changes, is demonstrated by the appearance

of a proliferation of small ducts in a fibrous stroma. Although it is benign, the gross and mammographic

appearance may mimic carcinoma, and it can be difficult to distinguish from carcinoma on frozen section.

There is prominent Apocrine Metaplasia change of the cells lining the cysts in this example of fibrocystic changes of breast. Note the tall, pink, columnar nature of the epithelial cells. This appearance is

benign.

A small benign intraductal papilloma appears here in a breast duct, typically in one of the main lactiferous

ducts beneath the areola. Note that the epithelial cells show no atypia and that there is a fine pink collagenous stroma within the papilloma. An intraductal papilloma

may be associated with a serous or bloody nipple discharge, or it may cause some nipple retraction.

Infiltrating ductal carcinoma, the pleomorphism of the carcinoma cells

within the duct in the center (in a cribriform pattern), as well as the

neoplastic cells infiltrating through the stroma and fat, can be seen

“Scirrhous carcinoma of the breast” , small nests and infiltrating strands of neoplastic cells with prominent

bands of collagen between them. It is this marked increase in the dense fibrous tissue stroma that produces the characteristic hard "scirrhous"

appearance of the typical infiltrating ductal carcinoma. Note the nerve surrounded by the neoplasm at the

lower left. BACK

Lobular carcinoma in situ is seen here. Lobular CIS consists of a neoplastic proliferation of cells in the terminal breast ducts and acini. The cells are small and round. Though these lesions are low grade, there is a 30% risk for development of invasive carcinoma in the same or the opposite breast.

The cells of this breast carcinoma are highly positive for estrogen receptor with this immunoperoxidase stain. Estrogen receptor positivity correlates with a better prognosis because such positive neoplastic cells are better differentiated and more sensitive to hormonal

manipulation. BACK

Paget's cells of Paget's disease of breast have abundant clear cytoplasm and appear in the epidermis either singly or in clusters. The nuclei of the Paget's cells are atypical

and, though not seen here, often have prominent nucleoli

This variant of breast cancer is known as colloid, or mucinous, carcinoma. Note the abundant bluish

mucin. The carcinoma cells appear to be floating in the mucin. This variant tends to occur in older women and

is slower growing, and if it is the predominant histologic pattern present, then the prognosis is better than for

non-mucinous, invasive carcinomas.

CLASSIFICATION OF TUMOURS

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