Structural decay of bone microarchitecture in men with prostate cancer treated with androgen deprivation therapy.
BACKGROUND
Androgen deprivation therapy (ADT) used in the treatment of prostate cancer reduces bone mineral density (BMD) and predisposes to fractures. The structural basis of the BMD deficit and bone fragility is uncertain.


OBJECTIVE
We investigated changes in bone microarchitecture in 26 men (70.6±6.8 yr) with nonmetastatic prostate cancer during the first year of ADT using the new technique of high-resolution peripheral quantitative computed tomography.


METHODS
We conducted a 12-month prospective observational study in the setting of a tertiary referral center.


RESULTS
After 12 months of ADT, total volumetric density decreased by 5.2±5.4% at the distal radius and 4.2±2.7% at the distal tibia (both P<0.001). This was due to a decrease in cortical volumetric BMD (by 11.3±8.6% for radius and 6.0±4.2% for tibia, all P<0.001) and trabecular density (by 3.5±6.0% for radius and 1.5±2.3% for tibia, all P<0.01), after correcting for trabecularization of cortical bone. Trabecular density decreased due to a decrease in trabecular number at both sites (P<0.05). Total testosterone, but not estradiol, levels were independently associated with total and corrected cortical volumetric BMD at the tibia.


CONCLUSIONS
Sex steroid deficiency induced by ADT for prostate cancer results in microarchitectural decay. Bone fragility in these men may be more closely linked to testosterone than estradiol deficiency.
Hamilton
E J
EJ
Department of Medicine, Austin Health/Northern Health, University of Melbourne, Studley Road, Heidelberg, Victoria 3084, Australia.
Ghasem-Zadeh
A
A
Gianatti
E
E
Lim-Joon
D
D
Bolton
D
D
Zebaze
R
R
Seeman
E
E
Zajac
J D
JD
Grossmann
M
M
D000368:Aged; D000726:Androgen Antagonists / Q000627:therapeutic use*; D001823:Body Composition; D015992:Body Mass Index; D015519:Bone Density / Q000187:drug effects*; D001862:Bone Resorption / Q000139:chemically induced; D001842:Bone and Bones / Q000000981:diagnostic imaging / Q000187:drug effects / Q000473:pathology*; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000453:epidemiology / Q000473:pathology*; D011859:Radiography; D011884:Radius / Q000187:drug effects / Q000473:pathology; D013977:Tibia / Q000187:drug effects / Q000473:pathology
D000726:Androgen Antagonists