Bone mineral density changes in prostate cancer patients on androgen deprivation therapy 


The objective of our study was to characterize bone mineral density changes in prostate cancer patients on androgen deprivation therapy (ADT) during the first two years of uninterrupted therapy. Moreover we tried to identify which location best reflects bone mass loss.  

Using dual energy x-ray absorptiometry, bone mineral density was prospectively assessed in non metastatic prostate cancer patients, at the lumbar spine and femoral neck, Ward´s triangle, trochanter and total hip. Measurements were performed at baseline and yearly thereafter in ADT patients and at baseline and 1 year in controls (age-matched prostate cancer patients, free of biochemical progression after radical prostatectomy). A group of 61 patients were included; 31 in each group. Median age (70 and 69y. respectively), mean Gleason score and mean baseline serum testosterone did not significantly differ.  Patients under ADT experienced a significant bone mass loss at 12m in all locations, ranging from 2.29% to 5.55% (p<0.001). In contrast, bone mineral density did not change significantly (0.64% to 1.68%) in non ADT patients. In the 20 ADT patients followed during 24m, second year decrease was not as severe, nor was significant when compared to the first year values. Ward´s triangle was the location that reflected the major bone mass loss, with decreases reaching a 5.55% at 12m and 7.05% at 24m.

We concluded that bone mineral density decreases during the first 24 months of androgen suppression with the most relevant effect during the first year. Wards’ triangle is the axial skeletal site that reflects the major bone mass loss. Because, the deleterious impact of long term androgen suppression in bone mineral density is inversely related to fracture risk and indirectly to survival in prostate cancer patients, early diagnosis and prevention of bone mass loss is warranted in these patients.

 

Bibliographical reference:

Morote J et al.: "Bone mineral density changes in patients with prostate cancer during the first 2 years of androgen suppression", J Urol. 2006 May;175(5):1679-83

 

Juan Morote

Department of Urology, Vall d'Hebron Hospital, Autonoma University School of Medicine, Barcelona, Spain