2. INTRODUCTION
• Prostate cancer has the propensity to spread
to bones
• In autopsy studies – men who died of
metastatic prostatic cancers, 91% had bone
mets.
3. • Seed and Soil theory by Paget
– Seed is the prostate
– Soil is the bone
• Proliferation occurs in axial skeleton – ribs,
pelvis and spine.
– Because of abundant RED MARROW
4. PATHOPHYSIOLOGY
• Primary tumor cells penetrate the BM ->
invades the blood vessels and lymphatics ->
proliferation of tumor cells ->migrate to
distant capillary beds -> escape the
vasculature by extravasation.
5. • How prostate CA spreads to the lumbar spine?
• By BATSON’S plexus
– The Batson venous plexus drains the vetebrae and
skull and forms anastamosis with veins draining the
thoracic, abdominal, and pelvic organs and breast.
– the extradural venous plexus
– Valveless venous system
– Low pressure and high volume
9. SKELETAL RADIOGRAPHY
• The skeleton – mc – 85%
• Plain flims – not sensitive (atleast 50% change
in bone density should occur)
• Radionucleotide scans have replaced Xrays, so
where can we do x rays?
– Inconclusive bone scans
– Specific site of pain to evaluate impending
fracture
10. • Osteoblastic > Osteolytic Cas
• Common sites are pelvic and lumbar spine.
• DD for osteolytic lesions? – mets from other
cancers like thyroid, lungs and colon, myeloid
metaplasia, flurosis and osteopoikilosis.
• Revesered by endocrine therapy
• Transient accentuation of osteoblastic lesion after
orchidectomy or androgen blockade is seen.
11.
12.
13. BONE SCINTIGRAPHY
• Highly sensitive
• Percentage of lesions identified by bone scan
which was not visible on skeletal survey is 23%
• False negativity can also occur.
– In that case if PSA > 50 meand – Occult mets +
• PSA is also useful to help us to choose patients
for bone scan.
– In asymptomatic patients, PSA >10 – 1% Bone scan
positive
• T3 or poorly differentiate CA – bone scan
indicated regardless of PSA.
14. CHEST RADIOTHERAPY
• 6% - have intrathoracic mets
• In stage 4 disease – 25%
• Without chest XRAY– true stage is
underestimated
• At this age group anyway chest imaging is
warranted to rule out other pathologies.
• Lymphangitic spread is more common than
typical discrete nodules.
16. LYMPHANGIOGRAPHY
• Not recommended
• Mets in the form of intranodal filling defect.
• Met deposits as small as 5 mm can be
detected.
• Always confirm with FNAC
17.
18. CT
• Primary role in the detection of LN mets
• Low yield of positive studies
• Results based on size criteria
– >1cm considered abnormal
• Sen – 30-78%
• Spe – 77-97%
• Accuracy – 70-94%
• All enlarged nodes should be biopsied
19. • RP lymphadenopathy is uncommon without
pelvic lymphadenopathy
• Although CT can detect blastic and lytic
lesions, it should not be used to screen bone
lesions.
20.
21.
22. MRI
• LNs are low signal intensity in T1 and high in
T2.
• Osteoblastic mets are low intense in T1 and T2
• MRI in bone mets
– When other studies are inconclusive
– Spinal compression?
• MRI helpful for local staging and not for
systemic staging.
23.
24. CONCLUSION
• Men with advanced prostate cancer are at high risk for the
development of bone metastases and associated skeletal
complications.
• Tumor cells produce stromal factors that affect cell adhesion,
motility, and migration.
• Tumor cells disrupts normal bone remodelling by secreting a variety
of factors stimulating both osteoclastic and blastic bone formation.
• Increased bone resorption leads to release of many bone derived
growth factors that promotes tumor proliferation.
• Zolendronic acid.
