The Value Of Pretreatment Clinical And Biochemical Parameters In Staging And Prognostic Stratification Of Patients With Newly Diagnosed Prostate Carcinoma
To determine whether it is possible to select patients in whom and for what reason bone scintigraphy should be performed or not, a retrospective study was performed of 161 consecutive patients with newly diagnosed prostate cancer.
Follow-up varied from 1 to 88 months during which 67 patients died. Bone scans were classified from 0 (= normal) to 3 (typical pattern of metastases) and were correlated with age, alkaline phosphatase (AP), prostate specific antigen (PSA), tumor grade, TNM-stage and survival. For survival, 68 patients who were not referred for bone scintigraphy were also evaluated.
All parameters demonstrated a correlation with the incidence of a positive bone scan, but PSA was the best overall predictor in this (p<0.0001). None of the patients with PSA ≤ 20 ng/ml (n=64) showed metastases, whereas 8 of 9 patients with PSA > 1000 ng/ml and patients with PSA values between 20 and 1000 ng/ml in combination with AP >90 U/L (n=24) had bone metastases. Furthermore, a class 3 bone scan was found to be the most important parameter in assessing prognosis and survival (p<0.0001), whereas no differences were found in patients with a class 0, 1 and 2 scintigram.
For staging and prognostic stratification purposes, bone scintigraphy and additional roentgenograms are of value in a selected group of patients. In contrast with a typical pattern of metastases on bone scintigraphy, an abnormal scan (class 1 and 2) at the time of diagnosis is not a poor prognostic parameter of the risk of death. Bone scintigraphy can be omitted in patients with PSA values < 20 ng/ml. In patients with PSA levels > 1000 ng/ml or less increased levels combined with alkaline phosphatase levels > 90 U/L, bone scintigraphy seems to be of no value in staging disease.