Prostatic cancer surveillance following whole-gland high-intensity focused ultrasound: comparison of MRI and prostate-specific antigen for detection of residual or recurrent disease

Abstract

Objective: This retrospective study compares dynamic contrast-enhanced (DCE) MRI with the serial prostate-specific antigen (PSA) measurement for detection of residual disease following whole-gland high-intensity focused ultrasound (HIFU) therapy of prostate cancer. Methods: Patients in whom post-HIFU DCE-MRI was followed within 3 months by ultrasound-guided transrectal biopsy were selected from a local database. 26 patients met the study inclusion criteria. Serial PSA levels following HIFU and post-HIFU followup MRI were retrieved for each patient. Three radiologists unaware of other investigative results independently assessed post-HIFU MRI studies for the presence of cancer, scoring on a four-point scale (1, no disease; 2, probably no disease; 3, probably residual disease; and 4, residual disease). Sensitivity, specificity and receiver operating characteristic (ROC) analysis were performed for each reader, post-HIFU PSA nadir and pre-biopsy PSA level thresholds of .0.2 and .0.5 ng ml 21. Results:The sensitivity of DCE-MRI for detection of residual disease for the three readers ranged between 73% and 87%, and the specificity between 73% and 82%. There was good agreement between readers (k50.69-0.77). The sensitivity and specificity of PSA thresholds was 60-87% and 73-100%, respectively. The area under the ROC curve was greatest for pre-biopsy PSA (0.95). Conclusion: DCE-MRI performed following whole-gland HIFU has similar sensitivity and specificity and ROC performance to serial PSA measurements for detection of residual or recurrent disease.

Imaging modalities in focal therapy

“…Sensitivity ranged between 73% and 87% between 3 readers, whereas specificity ranged between 73% and 82%. These results were comparable with pre-biopsy PSA levels [42]. …”

Medium-term Outcomes after Whole-gland High-intensity Focused Ultrasound for the Treatment of Nonmetastatic Prostate Cancer from a Multicentre Registry Cohort

“…Fourthly, not all patients received postoperative biopsies as these were only carried out on a ''for-cause'' basis due to rising PSA or a prostate MRI suggestive of residual or recurrent disease. Our previous report has showed that such a strategy was accurately valid [9]. Finally, there was a significant rate of retreatment that many would argue is a weakness, although the ability to re-apply the same treatment might be considered an advantage.…”

“…Two rises in PSA after nadir, without predefining the level of rise, was investigated with a prostate biopsy or MRI followed by biopsy if the MRI was suspicious[9]. All centres and surgeons underwent a rigorous period of training and proctoring by expert HIFU operators involving online learning, observation of at !5 cases on two separate occasions in an expert centre and on-site proctoring by an expert urologist for !5 cases followed by the presence of a senior expert clinical applications specialist for all subsequent treatments.…”

Ultrasonic Enhancement of Drug Penetration in Solid Tumors

“…Multiple MRI protocols can be proposed for the guidance of ultrasound therapies including diffusion-weighted (75, 76), T2-weighted (77, 78), and contrast enhanced T1-weighted imaging (79–81), fluid attenuated inversion recovery (FLAIR) (82), heteronuclear ( 23 Na) (83), spectroscopy (84), and displacement sensitive sequences via MR elastography (85). Following HIFU ablation of the prostate, gadolinium enhanced MRI is often used to evaluate the extent of tissue damage.…”