Safety and Feasibility of Transperineal Targeted Microwave Ablation for Low- to Intermediate-risk Prostate Cancer

Background

Focal therapy has emerged as an interesting option for localized low- to intermediate-risk prostate cancer (PCa). Targeted microwave ablation (TMA) is a novel FT modality involving targeted delivery of microwave energy under multiparametric magnetic resonance imaging (MRI)/ultrasound guidance.

Objective

To describe the step-by-step procedure for TMA and report early functional outcomes.

Design, setting, and participants

This was an experimental phase 1–2 trial in 11 patients diagnosed with a single, MRI-visible PCa lesion of up to 12 mm, scored as International Society of Urological Pathology grade group (GG) 1 or 2.

Surgical procedure

Transperineal TMA under MRI/ultrasound image fusion guidance.

Measurements

We recorded patient and PCa features; intraoperative and postoperative parameters; pain (Visual Analog Scale [VAS]) and adverse events (Common Terminology Criteria for Adverse Events v5.0); and prostate-specific antigen (PSA), International Prostate Symptom Score (IPSS) and International Index of Erectile Function (IIEF-5) scores at 1 wk and 1, 3, and 6 mo.

Results and limitations

The median patient age was 67 yr (interquartile range [IQR] 18). Median PSA was 5.4 ng/ml (IQR 1.8), median prostate volume was 51 cm³ (IQR 35), and median lesion size on MRI was 10 mm (IQR 4). Ten patients had GG 2 PCa and one had GG 1 disease. The median procedure time was 40 min (IQR 30). No intraoperative complications were reported. All treatments were performed on a day-case basis and no patients were discharged with a urinary catheter. Postoperatively, no grade ≥2 complications were reported. No significant changes in PSA (p = 0.46), IPSS (p = 0.39), or IIEF-5 scores (p = 0.18) scores were reported. The postoperative VAS score at 24 h was 0 for all patients.

Conclusions

TMA is safe, feasible, and well tolerated in patients with low- to intermediate-risk PCa. Oncological outcomes are still awaited.

Patient summary

Targeted microwave therapy is safe and feasible for selected patients with low- to intermediate-risk prostate cancer. The procedure is well tolerated and does not require a urinary catheter after the procedure. Cancer control outcomes are still awaited.

Elastic fusion biopsy versus systematic biopsy for prostate cancer detection: Results of a multicentric study on 1,119 patients

OBJECTIVES

To assess the accuracy of targeted and systematic biopsies for the detection of prostate cancer (PCa) and clinically significant PCa (csPCa) in the everyday practice, evaluating the need for additional systematic biopsies at the time of targeted biopsy.

PATIENTS AND METHODS

From our multicentric database gathering data on 2,115 patients who underwent fusion biopsy with Koelis™ system between 2010 and 2017, we selected 1,119 patients who received targeted biopsies (a median of 3 for each target), followed by systematic sampling of the prostate (12 to 14 cores). Overall and clinically significant cancer detection rate (CDR) of Koelis™ fusion biopsies were assessed, comparing target and systematic biopsies. Secondary endpoint was the identification of predictors of PCa detection.

RESULTS

The CDR of targeted biopsies only was 48% for all cancers and 33% for csPCa. The performance of additional, systematic prostate sampling improved the CDR of 15% for all cancers and of 12% for csPCa. PCa was detected in 35%, 69%, and 92% of patients with lesions scored as PI-RADS 3, 4 and 5, respectively. Elevated PI-RADS score and positive digital rectal examination were predictors of PCa, whereas biopsy-naïve status was associated with csPCa.

CONCLUSION

In the everyday practice target biopsy with Koelis™ achieves a good CDR for all PCa and csPCa, which is significantly improved by subsequent systematic sampling of the prostate. The outstanding outcomes of fusion biopsy are confirmed also in biopsy-naïve patients. Elevated PI-RADS score and positive digital rectal examination are strongly associated with presence of PCa.

Accuracy of elastic fusion biopsy in daily practice: Results of a multicenter study of 2115 patients

OBJECTIVES

To assess the accuracy of Koelis fusion biopsy for the detection of prostate cancer and clinically significant prostate cancer in the everyday practice.

METHODS

We retrospectively enrolled 2115 patients from 15 institutions in four European countries undergoing transrectal Koelis fusion biopsy from 2010 to 2017. A variable number of target (usually 2-4) and random cores (usually 10-14) were carried out, depending on the clinical case and institution habits. The overall and clinically significant prostate cancer detection rates were assessed, evaluating the diagnostic role of additional random biopsies. The cancer detection rate was correlated to multiparametric magnetic resonance imaging features and clinical variables.

RESULTS

The mean number of targeted and random cores taken were 3.9 (standard deviation 2.1) and 10.5 (standard deviation 5.0), respectively. The cancer detection rate of Koelis biopsies was 58% for all cancers and 43% for clinically significant prostate cancer. The performance of additional, random cores improved the cancer detection rate of 13% for all cancers (P < 0.001) and 9% for clinically significant prostate cancer (P < 0.001). Prostate cancer was detected in 31%, 66% and 89% of patients with lesions scored as Prostate Imaging Reporting and Data System 3, 4 and 5, respectively. Clinical stage and Prostate Imaging Reporting and Data System score were predictors of prostate cancer detection in multivariate analyses. Prostate-specific antigen was associated with prostate cancer detection only for clinically significant prostate cancer.

CONCLUSIONS

Koelis fusion biopsy offers a good cancer detection rate, which is increased in patients with a high Prostate Imaging Reporting and Data System score and clinical stage. The performance of additional, random cores seems unavoidable for correct sampling. In our experience, the Prostate Imaging Reporting and Data System score and clinical stage are predictors of prostate cancer and clinically significant prostate cancer detection; prostate-specific antigen is associated only with clinically significant prostate cancer detection, and a higher number of biopsy cores are not associated with a higher cancer detection rate.