Prostate Cancer

Question 1

What is the epidemiology of prostate cancer?

Answer 1

• Commonest cancer in males
• More than 47,000 new cases in the UK in 2015
• Predominantly disease of older men
• more than 50% occurring over the age of 75

Question 2

What are the risk factors for developing prostate cancer?

Answer 2

• no clear aetiological agents
• radiation exposure
• diet
• anabolic steroids
• increasing age
• afriacan and afro-caribbean backgrounds
• family Hx
• men whose mother was diagnosed with breast cancer
• BRCA11 and pTEN mutations

Question 3

What is the histology of prostate cancer?

Answer 3

• Over 95% are adenocarcinomas
• Developing in glandualr tissue in posterior or perioheral parts of the prostate gland
• Benign prostatic hyperplasia more commonly aises in the centre of the gland

Question 4

What is the characteristic presentation of prostate cancer?

Answer 4

• Asymptomatic
• May present with:
  
  • local lower urinary tract symptoms
  • poor stream
  • nocturia
  • dribbling
  • increased frequency
  • Impotence is common
• 1 in 5 have metastatic prostate cancer = bone complications
  
  • anaemia
  • pain
  • pathological fracture
  • spinal cord compressin

Question 5

What are the Initial Investigation for suspected prostate cancer?

Answer 5

• Digital rectal exam
  
  • note this will put PSA up after doing so need gap before requesting blood test
• Serum prostate-specfic antigen (PSA) blood test

Question 6

What further investigations may be relevant for prostate cancer?

Answer 6

• MRI
  
  • visualises prostate well
  • needed for radical curative treatment
• Isotope radionucleotide bone scan
  
  • is concern about metastatic disease
  • radiolabelled technetium taken up by oestoblasts at sites of bone remodelling
• Ultrasound guided transrectal biopsy

Question 7

What PSA level makes clinicla suspician of prostate cancer high? Meaning?

Answer 7

• PSA > 100 with positive bone scan
• Ultrasound guided biopsy not required to confirm diagnosis

Question 8

What staging system is used for prostate cancer?

Answer 8

• TNM staging system used

Question 9

What grading system is used for prostate cancer? Describe it

Answer 9

• Gleason system
• Scores tumours from 2 - 10 on the basis of histological patterns in the two dominant areas
• e.g. Gleason 4 + 3 means main area is 4 with second are 3

Question 10

What is the management of prostate cancer?

Answer 10

• PSA, histological grade and stage used to counsel patients on management options

Observation

• in patients with asymptomat disease confined to prostate
• radical treatment unlikely to benefit men with life expectancy of less than ten years

Surgery

• with localised disease (T2 or less) can have radical prostatectomy with curative intent
• Palliative surgery (trans-urethral resection) used to reliev prostatic sympotms or urinary obstruction

Radiotherapy

• alternative to surgery in T1 and T2 tumours where PSA is low
• Low PSA suggest no occult metastaases
• adjuvant radiotherapy may also be given
• may be performed by external bearm irradiation, or brachytherapy
• palliative radiotherapy may be used

Hormonal therapy

• used for treating advanced disease or with radiotherapy
• inhibition of growth-stimulatory effect of endogenous androgens may effectively treat, response rate 80%

Chemotherapy

• Cytotoxic treatment with docetaxel (combo with prednisolone)
• Used around time of diagnosis of metastatic prostate cancer

Question 11

What hormonal therapy can be given to treat prostate cancer? Why

Answer 11

Inhibits endogenous androgens =treats the cancer =response rate 80%

• LHRH Agonists (luteinizing-hormone releasing hormone)
  
  • reduces level of cirulating testosterone
  • given monthly or 3 monthly subcut or IM injections
  • side effects: impotence, loss of libido, tumour flate
• Gonadotrophin eleasing hormone antagonist
  
  • leads to castrate levels of testoterone in 96% of patients within 3 days
  • monthly subcut Injection
• Oestrogen therapy
  
  • inhibit LHRH production from hypothalamus
  • rarely best option due to side effects: impotence, loss of libido, gynaecomastia
• Anti-androgens
  
  • compete with androgens for sites on androgen receptor
• Bilaterla orchidectomy

Question 12

What is the prognosis of prostate cancer?

Answer 12

• Survival related to extent of the disease
• Suvival with low risk localised prostate cancer is 99% at 10 years
• Of all UK patients 10 year survival 84%
• Patients with metastatic disease median survial of 3.5years

Question 13

Why has PSA screening not been introduced?

Answer 13

• Due to poor sensitivity and specificity of PSA testing
• Many of early tumours picked up through screening may never be a clinical problem during the remainder of patients natural life