E5077. Impact of Postbiopsy Hemorrhage on MRI-Based Prostate Cancer Interpretation: Is Prolonged Interval Still Necessary in the PI-RADS Era?
Authors
Baichuan Liu;
Department of Radiology, First Medical Center of Chinese PLA General Hospital
Xu Bai;
Department of Radiology, First Medical Center of Chinese PLA General Hospital
Xiaohui Ding;
Department of Pathology, First Medical Centre; of Chinese PLA General Hospital
Huiyi Ye;
Department of Radiology, First Medical Center of Chinese PLA General Hospital
Haiyi Wang;
Department of Radiology, First Medical Center of Chinese PLA General Hospital
Objective:
To the purpose of this study is to investigate the impact of intervals after biopsy on tumor detection and local staging using multiparametric MRI (mpMRI).
Materials and Methods:
This retrospective study included 130 patients with prostate cancer (PCa) who underwent subsequent mpMRI after ultrasound-guided systematic biopsy. The percentages of hemorrhage volume in the total prostate were drawn and calculated. Two genitourinary radiologists evaluated and localized the lesions according to PI-RADS 2.1. The probability of EPE was additionally assessed using EPE grade. Discrepancies between readers were resolved via consensus, then adjudicated by a third expert radiologist in prostate MRI. Patients were divided into three groups: group A (n = 31), group B (n = 67), and group C (n = 32), according to the intervals after biopsy of 3 and 6 weeks, respectively. The registration of MR images to pathologic tumor maps was performed in a single session. Correlations between the hemorrhage extent and interval days were analyzed by using the Spearman correlation coefficient (r). ROC curves were used to evaluate the performance in assessing EPE. The accuracy for tumor detection and the AUC for EPE prediction were compared with Kruskal-Wallis H-test and Delong test, respectively.
Results:
The median interval between biopsy and prostate MR examination was 33 days (IQR, 22–42). The percentage of hemorrhage was significantly correlated with the interval time between biopsy and MR examination (r = -0.325, p < 0.001). The accuracy for tumor detection was 80.6%, 73.1%, 75.0%, and 75.4% for group A, B, C, and overall patients. There was no significant difference in the detectability among the three groups (p = 0.723). For EPE prediction, the AUCs were 0.866 (95% CI: 0.695– 0.961), 0.813 (95% CI: 0.699–0.898), 0.834 (95% CI: 0.661–0.941), and 0.823 (95% CI: 0.695–0.961) for group A, B, C, and overall patients, respectively. There were no significant differences among the subgroups (p = 0.511 for group A and B, p = 0.750 for group A and C, p = 0.818 for group B and C).
Conclusion:
The hemorrhage extent was negatively correlated with the intervals between biopsy and MRI examination. However, the interval period did not affect the detection accuracy and EPE assessment for PCa using mpMRI. There is probably no necessity for prolonged intervals following systematic biopsy to preserve the clarity of MRI interpretation of prostate cancer.
