Prognostic value of Alkaline Phosphatase in Adults  with Localised Osteosarcoma

Prognostication in osteosarcoma remains a problem. It would be helpful if objective instruments were available early in treatment, preferably before surgery. Alkaline phosphatase is easy to determine and has been shown to have a predictive value for survival. Most authors however report only on alkaline phosphatase level before chemotherapy, or after surgery. In this study the prognostic value of Alkaline Phosphatase (AP), measured before and after chemotherapy, but before surgery was established in a retrospective survey of patients, 18 years or older, with non-metastatic, high grade osteosarcoma.  AP was classified as Normal (<100% upper limit), High (100%<AP<200%) or Very-High (AP>200%). 

AP was not correlated with local recurrence. Normal or High pre-chemotherapy AP correlated with better survival at 10 years (64% and 70%) than Very-High pre-chemotherapy AP (37%, p=0.005). Post-chemotherapy AP correlated with survival (68%, 39% and 25% in the Normal, High and Very-High group, p=0.0007) and response to chemotherapy (p=0.049).

A pre-chemotherapy AP over twice normal correlates with worse survival. If AP is decreased after chemotherapy, but still raised, survival is better, but still worse then if AP normalises. A raised post-chemotherapy AP predicts poor chemotherapy response.

 

Bibliographical reference:

Bramer JA et al.: "Pre- and post-chemotherapy alkaline phosphatase levels as prognostic indicators in adults with localised osteosarcoma", Eur J Cancer. 2005 Dec;41(18):2846-52. Epub 2005 Nov 7

 

Jos Bramer

Royal Orthopaedic Hospital, Birmingham, UK; Department of Orthopaedic Surgery, Academic Medical Center, Amsterdam, The Netherlands