Clinical value of ^99mTc-MDP bone scintigraphy combined with determination on serum t-PSA and f-PSA in diagnosis of prostatic cancer

Objective: To compare the clinical efficiency of serum total prostate specific antigen(t-PSA) and free-PSA(f-PSA) for prostatic cancer and ^99mTc-MDP bone scintigraphy(BS) for bone metastasis. To explore the diagnostic value of PSA combined with BS in diagnosing prostatic cancer. Methods: To analysed retrospectively on serum PSA levels were measured in 33 patients of prostatic cancer and 14 patients of prostatic hyperplasia who all underwent ⁹⁹mTc-MDP BS. BS images were interpreted according to 5-point scale (O: definitely negative, 1: probably negative, 2: equivocal, 3: probably positive, 4: definitely positive for bone metastasis). ROC analysis was performed. Results: The area under the ROC curve of t-PSA, f-PSA and BS were 0.686, 0.637 and 0.948 respectively. The diagnostic sensitivity and specificity of the best domain value points were 57.6%, 78.6%; 84.8%, 42.9%; 90%, 82.6% individually. Conclusion: PSA combined with ^99mTc-MDP BS could diagnose prostatic cancer effectively and exclude the benign cases with high PSA levels, avoid unnecessary traumatic examination. (authors)