Bone imaging and serum phosphatases in prostatic carcinoma.

Area of Science:

• Oncology
• Biochemistry
• Radiology

Background:

• Locally advanced prostate cancer frequently presents with or develops bone metastases.
• Monitoring treatment response in these patients is critical for effective management.
• Current monitoring methods include radionuclide imaging and biochemical markers like phosphatases.

Purpose of the Study:

• To evaluate the efficacy of serial radionuclide imaging and plasma phosphatase measurements in monitoring bone metastases during hormonal therapy for prostate cancer.
• To compare the diagnostic and prognostic value of alkaline phosphatase and acid phosphatase in this patient cohort.

Main Methods:

• One hundred twenty-seven patients with locally advanced prostate cancer were studied.
• Serial radionuclide imaging and frequent measurements of plasma acid (tartrate-labile) and alkaline phosphatase were performed before and during hormonal therapy.
• Changes were classified into six groups for comparison.

Main Results:

• Of 71 patients with negative imaging initially, most had normal phosphatase levels.
• In 56 patients with bone metastases at presentation, false negative phosphatase levels were observed in 18% (alkaline) and 36% (acid).
• Serial alkaline phosphatase showed treatment response not always evident on imaging; acid phosphatase was less effective.

Conclusions:

• Serial alkaline phosphatase estimation is essential for follow-up in prostate cancer patients with bone metastases.
• Alkaline phosphatase monitoring may render serial imaging studies superfluous after skeletal metastases are confirmed.
• Acid phosphatase is a significantly less effective marker compared to alkaline phosphatase.