Bone scan positivity in non-metastatic, castrate-resistant prostate cancer: external validation study

ABSTRACT Introduction: Tables predicting the probability of a positive bone scan in men with non-metastatic, castrate-resistant prostate cancer have recently been reported. We performed an external validation study of these bone scan positivity tables. Materials and Methods: We performed a retrospective cohort study of patients seen at a tertiary care medical center (1996-2012) to select patients with non-metastatic, castrate-resistant prostate cancer. Abstracted data included demographic, anthropometric, and disease-specific data such as patient race, BMI, PSA kinetics, and primary treatment. Primary outcome was metastasis on bone scan. Multivariable logistic regression was performed using generalized estimating equations to adjust for repeated measures. Risk table performance was assessed using ROC curves. Results: We identified 6.509 patients with prostate cancer who had received hormonal therapy with a post-hormonal therapy PSA ≥2ng/mL, 363 of whom had non-metastatic, castrate-resistant prostate cancer. Of these, 187 patients (356 bone scans) had calculable PSA kinetics and ≥1 bone scan. Median follow-up after castrate-resistant prostate cancer diagnosis was 32 months (IQR: 19-48). There were 227 (64%) negative and 129 (36%) positive bone scans. On multivariable analysis, higher PSA at castrate-resistant prostate cancer (4.67 vs. 4.4ng/mL, OR=0.57, P=0.02), shorter time from castrate-resistant prostate cancer to scan (7.9 vs. 14.6 months, OR=0.97, P=0.006) and higher PSA at scan (OR=2.91, P <0.0001) were significantly predictive of bone scan positivity. The AUC of the previously published risk tables for predicting scan positivity was 0.72. Conclusion: Previously published risk tables predicted bone scan positivity in men with non-metastatic, castrate-resistant prostate cancer with reasonable accuracy.

Bone scan positivity in non-metastatic, castrate-resistant prostate cancer: external validation study.

INTRODUCTION: Tables predicting the probability of a positive bone scan in men with non-metastatic, castrate-resistant prostate cancer have recently been reported. We performed an external validation study of these bone scan positivity tables. MATERIALS AND METHODS: We performed a retrospective cohort study of patients seen at a tertiary care medical center (1996-2012) to select patients with non-metastatic, castrate-resistant prostate cancer. Abstracted data included demographic, anthropometric, and disease-specific data such as patient race, BMI, PSA kinetics, and primary treatment. Primary outcome was metastasis on bone scan. Multivariable logistic regression was performed using generalized estimating equations to adjust for repeated measures. Risk table performance was assessed using ROC curves. RESULTS: We identified 6.509 patients with prostate cancer who had received hormonal therapy with a post-hormonal therapy PSA ≥2ng/mL, 363 of whom had non-metastatic, castrate-resistant prostate cancer. Of these, 187 patients (356 bone scans) had calculable PSA kinetics and ≥1 bone scan. Median follow-up after castrate-resistant prostate cancer diagnosis was 32 months (IQR: 19-48). There were 227 (64%) negative and 129 (36%) positive bone scans. On multivariable analysis, higher PSA at castrate-resistant prostate cancer (4.67 vs. 4.4ng/mL, OR=0.57, P=0.02), shorter time from castrate-resistant prostate cancer to scan (7.9 vs. 14.6 months, OR=0.97, P=0.006) and higher PSA at scan (OR=2.91, P<0.0001) were significantly predictive of bone scan positivity. The AUC of the previously published risk tables for predicting scan positivity was 0.72. CONCLUSION: Previously published risk tables predicted bone scan positivity in men with non-metastatic, castrate-resistant prostate cancer with reasonable accuracy.

Evaluation of the Fluorescence In Situ Hybridization Test to Predict Recurrence and/or Progression of Disease after bacillus Calmette-Guérin for Primary High Grade Nonmuscle Invasive Bladder Cancer: Results from a Prospective Multicenter Trial.

PURPOSE: Single center studies have shown that positive UroVysion® fluorescence in situ hybridization results were associated with recurrence of nonmuscle invasive bladder cancer treated with intravesical bacillus Calmette-Guérin. Our goal was to validate these findings. MATERIALS AND METHODS: We performed a prospective, multicenter diagnostic trial to determine whether the fluorescence in situ hybridization test could predict recurrence or progression in patients with primary high grade nonmuscle invasive bladder cancer who were scheduled to receive bacillus Calmette-Guérin. Fluorescence in situ hybridization testing was performed prior to the first bacillus Calmette-Guérin instillation, prior to the sixth instillation and at 3-month cystoscopy. The performance of fluorescence in situ hybridization was evaluated. RESULTS: A total of 150 patients were enrolled in analysis, including 68 with Ta disease, 41 with T1 disease, 26 with carcinoma in situ alone and 15 with papillary carcinoma plus carcinoma in situ. At 9 months of followup there were 46 events, including 37 recurrences and 9 progressions. For events with positive fluorescence in situ hybridization findings the HR was 2.59 (95% CI 1.42-4.73) for the baseline test, 1.94 (95% CI 1.04-3.59) for the 6-week test and 3.22 (95% CI 1.65-6.27) at 3 months. Patients with positive results at baseline, 6 weeks and 3 months had events 55% of the time and patients with negative results at each time point had no event 76% of the time. CONCLUSIONS: The study validated that a positive UroVysion fluorescence in situ hybridization test was associated with a 3.3-fold increased risk of recurrence. The test may be useful to risk stratify patients entering clinical trials in whom induction therapy fails. However, using the test to change management decisions is limited due to the discordance between results and outcomes as well as the variance of tests results with time.