3 Tumour diagnosis and prognosis - stage and grade

Question 1

Describe how tumours are diagnosed

Answer 1

• Symptoms: clinical history
• Signs: physical examination (lumps and bumps)
• Imaging (X-ray - look for shadowing, MRI)
• Tumour markers (overactive - e.g. prostate-specific antigen (PSA) - overexpressed
• Biopsy: tissue sampling

Question 2

Describe how tumour markers can help in diagnosis

Answer 2

• Certain tumours liberate products that can be detected in blood/urine/CSF samples, thereby acting as tumour markers
• These may aid diagnosis but also be used to follow up therapy when blood levels become increased, often before imaging can detect tumour recurrence

Question 3

give some examples of tumor markers

Answer 3

• HCG - human chorionic gonadotrophin: from tumours with trophoblast elements
• AFP - alpha fetoprotein: liver cancer, germ cell tumours
• PSA - prostate-specific antigen from carcinoma of the prostate

High levels may not always mean cancer

Question 4

Describe how tumour biopsy used in diagnosis

Answer 4

Needed to confirm diagnosis - need a biopsy to look at cells involved to make sure that they show characteristics of tumour + check if it is benign or malignant

• Virtually every site in the body can be biopsied
• Tissue samples are acquired for examination
• Techniques used vary according to site and suspected diagnosis

Question 5

List some biopsy techniques

Answer 5

• Needle biopsy: in the brain, lymph node, eye, thyroid, breast, lung + pleura, liver, kidney, bone, bone marrow, testis, skeletal muscle
• Endoscopic biopsy: respiratory tract, alimentary tract, urinary tract
• Transvascular biopsy: kidney, heart
• Skin
• Cutterage biopsy - endometrial lining of uterus

Imaging can be used in conjunction with the biopsy technique, to guide the procedure

Question 6

Describe the handling of biopsy

Answer 6

• Fix in formalin solution for routine histology, special stains and immunohistochemistry
  > (protiens of tissue - HER2 expresssion in breast cancer - Herceptin can be used to target HER2+ patients that have this tumour)
• FIx in glutaraldehyde for electron microscopy
• Send fresh for cytogenetics, tumours

Question 7

Describe diagnostic cytology

Answer 7

• Examination of cells in tissue fluids or exfoliated from surfaces
• May give a diagnosis of malignancy
• Useful for screening - the main example is the cervical cytology programme
  > cervical smear - pap smear

Question 8

Explain how histology of neoplasms allows prediction of behavior

Answer 8

Two main assessments are made:

• analysis of the degree of differentiation and growth pattern of the tumor
• Evaluation of how far a tumour has spread

Special techinques may be used to obtain further prgnostic information

Question 9

Define and describe the grade (of a tumour)

[biology]

Answer 9

The degree of differentiation of tumour cells relative to normal tissue of origin

• Variation in size and shape of constituent cells of the tumour [pleomorphism]
• The proportion of cells containing mitotic figures [mitotic index]

Question 10

Describe the relatioship between grade and prognosis

Answer 10

In general
- LOW-grade tumours are SLOW growing, have a GOOD prognosis

• HIGH-grade tumours are FAST growing, have a POOR prognosis

These are very general rules that have to be considered with all other clinical aspects

Question 11

Describe histological grading in breast cancer

Answer 11

Assessment of the degree of differentiation of carcinoma from semi-quantitative analysis of its morphological characteristics:

• Tubule formation
• Nuclear pleomorphism
• Mitotic counts

[points given, depending on how much that variable is changed (low 1___3 high)]

Question 12

Describe the relationship between breast cancer grade and prognosis

Answer 12

Patients with low-grade tumours have longer survival than those with high-grade tumours

Question 13

What else can tumour grade be used for?

[predict ag**]

Answer 13

Grade can predict how aggressive cancer can be

- this can help with treatment choice/plans

Question 14

Describe + define tumour staging

Answer 14

[time-dependent factors]

• The size of primary tumors
• The degree to which it has locally invaded
• The extent to which it has spread by distant metastasis

Question 15

Describe the use of the TNM staging system

Answer 15

• The TNM system is based upon the extent of local tumour spread, regional lymph node involvement and the presence of distant metastases
• It can be applied to many different types of tumour, although the specific criteria are different for each tumour site

Question 16

Describe how the TNM staging works

Answer 16

The TNM staging system is used to describe most types of cancer:

• TUMOUR - describes the size of the tumour and any spread of cancer into nearby tissue
• NODES - describes spread of cancer to nearby lypmh nodes
• METASTASIS - descirbes metastasis to nearby lypmh nodes

The T, N, and M are given a score

(TX, 0, is, 1, 2, 3 ,4)
(NX, 0, 1, 2, 3)
(MX, 0, 1)
criteria can be found online
e.g. of a TNM staging
- T2N1M0

This TNM staging can be converted to a prognostic TNM stage

Question 17

Describe the relationship between stage and prognosis

Answer 17

• The stage of a tumour is generally the most important indicator of likely prognosis and of approporate tumour
• Advanced stage tumours (extensive spread) may require aggresive treatments
• Early stage tumours (locailised) may be treatable by relatively conservative measures

Question 18

Describe tumour therapy

Answer 18

Three main nodes of therapy for neoplastic disease

• Surgery (common 1st line treatment)
• Radiotherapy (treatment after surgery)
• Chemotherapy (treatment for [suspected] metastatic disease)

Multimodal therapy is common
- Pathology is pivotal in deciding on appropriate therapy

Question 19

Give an example of a tumour with excellent prognosis

Answer 19

Thyroid cancer

Question 20

Give an example of a tumour with a moderate prognosis

Answer 20

• Kidney, prostate, cervix, and breast cancer

Question 21

Give an example of a tumour with a very poor prognosis

Answer 21

• Pancreas, brain, esophagus cancer