The effects of the period between biopsy and diffusion‐weighted magnetic resonance imaging on cancer staging in localized prostate cancer

Abstract

Study Type – Diagnosis (exploratory cohort) Level of Evidence 2b OBJECTIVES To investigate whether there are any differences between preoperative magnetic resonance imaging (MRI) and the final pathology results, based on the time between biopsy and preoperative MRI, as there are reports recommending ≥3 weeks after a prostate biopsy, primarily because haemorrhaging interferes with the interpretation of MRI. PATIENTS AND METHODS Between December 2007 and December 2008, we retrospectively analysed 69 consecutive patients who had biopsy‐confirmed prostate cancer. The inclusion criteria for the study were a history of MRI investigation (combined T2‐weighted and diffusion‐weighted MRI) and robot‐assisted laparoscopic radical prostatectomy. The exclusion criteria included an MRI investigation‐to‐surgery interval of ≥1 week, a biopsy having been taken in another hospital, or other than 12 biopsy cores. The amount of haemorrhaging, number of haemorrhaging sites, and the location of the cancer were determined. For this, the prostate was divided into 12 segments which anatomically corresponded to the sites where the 12 core biopsies were taken. Each haemorrhagic prostate segment was scored according to its diameter. Pathology results were reviewed in the same manner. Finally, we assessed any discordance between the sets of results according to the period between the biopsy and the MRI. The association between the MRI and pathology results, in relation to the period between the biopsy and MRI, was plotted and tested using Pearson’s correlation coefficient. RESULTS Five of the 69 patients were excluded because they had a biopsy at another hospital, 12 were excluded because the period between the MRI and the surgery was >7 days. Suspected prostate haemorrhage was detected in 49 of 52 (94%) patients who had MRI. There was a significantly negative correlation with the period between biopsy and MRI (coefficient – 0.285, P= 0.041). There were no significant differences in cancer localization between MRI and pathology results according to the period between the biopsy and MRI (coefficient 0.028, P= 0.874). The rate of matching between MRI results and pathology results was 74%. CONCLUSIONS We found no significant differences in cancer localization between MRI and final pathology according to the period between the biopsy and MRI. Because of this finding, we do not recommend deferring MRI for the purpose of more accurate cancer staging.

Effects of Post Biopsy Digital Rectal Compression on Improving Prostate Cancer Staging Using Magnetic Resonance Imaging in Localized Prostate Cancer

“…Second, several studies have reported that post-biopsy hemorrhaging diminishes with time 3,6,11. We also observed a statistically significant negative correlation between the sum of the hemorrhage score and the time from the biopsy in our previous and current study 7. However, some authors argue that post-biopsy hemorrhaging is not significantly reduced until 55 days after the biopsy 12,13.…”

“…In this study, using multiparametric MRI, the timing of MRI did not affect the accuracy of PCa staging. Because multiparametric MRI usually has a greater sensitivity and specificity than conventional MRI, we believe that interpretation of MRI is less influenced by post biopsy hemorrhage 7,12,14,15. However, if the institute uses conventional MRI rather than multiparametric MRI for PCa staging, rectal compression may reduce the development of intraprostatic hemorrhage at biopsy.…”

Does performance of robot‐assisted laparoscopic radical prostatectomy within 2 weeks of prostate biopsy affect the outcome?

“…In our recent study, 8 post-biopsy hemorrhages were detected via magnetic resonance imaging up to 57 days after the biopsy and the total hemorrhage score was negatively correlated to the time from the biopsy. Our greater EBL in the surgery group within the 2 weeks after the biopsy might result from post-biopsy hemorrhage.…”

Accuracy of staging of oral squamous cell carcinoma of the tongue: should incisional biopsy be done before or after magnetic resonance imaging?

“…3,4,5 Other studies however, have found no significant difference in analysis and staging attributable to the period between the diagnostic biopsy and staging MRI. 6 Accurate OSCC staging is essential to provide patients and clinicians with information necessary to discuss and formulate critical treatment decisions. 7,8 This small cohort of patients with tongue OSCC demonstrates that undertaking biopsies before the staging MRI does not appear to compromise the accuracy of pre-treatment staging.…”