4.4 Prostate Flashcards
BPH
50-75% males >60 y/o
More common in Blacks, HTN, DM
Involves transitional zone - glandular tissue surrounding prostatic urethra, at proximal end veru montanum
IVP - ‘J-hook’ distal ureters (due to elevated interureteric ridge) ± ureteric dilatation / tortuosity if long-standing
Hyperplastic nodules high signal on T2W, can be low or high on T1W
Gleason Grading of Prostate Cancer
Grade 1: well differentiated, Grade 5: Poorly differentiated (4 & 5 have potential for lymphatic spread)
Overall score is sum of two predominant histological patterns summated to give overall score (2-4 well differentiated, 5-7 moderately differentiated, 8-10 poorly differentiated)
Prostate cancer - location
85% located in peripheral zone
Tumour grading and size predict prognosis
Cancer elevates PSA x10 more than BPH
Prostate cancer stage
T stage
1: only on histology or DRE
2a: half of one side
2c: both sides of prostate
3a: extracapsular extension without seminal vesicle invasion
3b: seminal vesicle invasion
4: spread to sphincter / rectum / pelvic wall
M stage
1: regional nodes;
1a: distant LNs
1b: osseous
1c: visceral disease
MRI Prostate cancer
Tumours in peripheral zone show relatively low T2W signal (but non-specific)
T1W detects haemorrhage
Cancer shows early rapid enhancement then early washout
Criteria for extracapsular spread: neurovascular asymmetry, angulated gland contour, obliteration of retroprostatic angle
Spectroscopy - cancers show low citrate and high choline (thus elevated choline/citrate ratio >2 SD above average for peripheral zone)
Mucinous adenocarcinoma and small infiltrating cancers hardest to detect
Prostate cancer nodal and metastatic spread
LNs: Obturator, Internal and external iliac LN’s;
80% with nodal disease develop bone metastases at 5 years
Osseous: 85% osteoblastic, 5% lytic, 10% mixed;
pelvis > lumbar > femur > thoracic;
PSA > 58 suggests bone metastases; PSA <20 and no bone pain - 0.2% risk bone metastases
Intrathoracic: 6% patients at first diagnosis
25% patients with stage D have lung or pleural disease
Lymphangitis carcinomatosis more common than lung nodules
