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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, PATIENTS AND METHODS, RESULTS. Meshes: Aged, Aged, 80 and over, Bone Neoplasms, Cohort Studies, Disease Progression, Humans, Male, Middle Aged, Prospective Studies, Prostate-Specific Antigen, Prostatic Neoplasms, Radionuclide Imaging, Radiopharmaceuticals, Sensitivity and Specificity, Technetium Tc 99m Medronate.
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Are serial bone scans useful for the follow-up of clinically localized, low to intermediate grade prostate cancer managed with watchful observation alone? Context: To assess the predictive value of serial bone scans as a surveillance tool for bone metastasis in men with clinically localized prostate cancer and managed with watchful observation. A prospective single-arm study was conducted to assess the feasibility of a watchful observation protocol with selective delayed intervention for patients with clinically localized prostate cancer, i.e. T1b-T2bN0M0, a Gleason score of<or= 7 and a prostate-specific antigen (PSA) level of<or= 15 ng/mL. Patients were managed expectantly as long as they did not meet the empirically predefined criteria of clinical, histological or PSA progression. Bone scintigraphy was repeated every year for the first 2 years, then every 2 years thereafter if the patient remained on watchful observation. When the follow-up PSA level was>15 ng/mL the patient underwent bone scintigraphy every year. In all, 244 eligible patients were enrolled into the study. With a median follow-up of 30 months, 449 bone scans were taken (150 at baseline and 299 in follow-up evaluations); all 299 follow-up scans were negative for bone metastasis. Hence, the true rate of positive follow-up bone scans was estimated to be 0-1.0% (95% confidence). In all, 171 patients had at least one follow-up bone scan; of these, the number (%) of patients who had 1, 2, 3, 4 and>or= 5 follow-up scans was 89 (52), 53 (31), 17 (10), eight (4.7) and four (2.3), respectively. The PSA levels (ng/mL) corresponding to all follow-up bone scans were: 214 scans at PSA<10, 61 at 10-14.9, 18 at 15-19.9 and six at>or= 20 (range 20.2-24.9). The probability of a negative bone scan was estimated to be 88-100% (95% confidence interval) when a PSA threshold of 15 ng/mL was used.
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The probability of positive findings in serial bone scans in untreated, localized, low to intermediate grade prostate cancer was low when the follow-up PSA level remained<15 ng/mL. Avoiding bone scans in this group of patients would translate into a significant cost saving and reduction in their psychological and physical burden. As for those with a follow-up PSA of>15 ng/mL, the role of serial bone scintigraphy remains undefined, as a longer follow-up and a larger sample are needed.