Table 2 Key findings of major PCa TULSA studies.

Chopra et al. [30]

2012

N = 8

Proof of principle [treat and resect] study [single center]

-mean age = 60 yr

-GS ≤ 7

-PSA < 15 ng/mL

Radical prostatectomy same day

Not reported

n/a

n/a

-Mean spatial targeting accuracy was -1.0 mm ± 2.6 mm

-No evidence of thermal effects on surrounding structures

Chin et al. [29]

2016

N = 30

Phase I safety and efficacy study [whole gland treatment] [multi center]

-Treatment-naïve men aged ≥65 yr with biopsy-proven organ confined PCa

-PSA ≤ 10 ng/mL

-GS 3 + 3 or 3 + 4

GS6 (3 + 3): 24 (80%)

GS7 (3 + 4): 6 (20%)

12 months

-No rectal injury or fistula,

-No G4 or higher adverse events

-1 epididymitis, resolved with IV antibiotics

-Median PSA decreased by 87% from 5.8 ng/mL at baseline, to 0.8 ng/mL at 1 month, and was stable at 0.8 ng/mL at 12 months

-Median IPSS values returned to baseline by 3 months

-Median IIEF-15 values returned to baseline by 12 months

At 12 months:

-16/29 (55%) patients had positive biopsy for any residual disease

-9/29 (31%) patients had clinically significant disease

-20/29 (69%) patients had no clinically significant disease

Klotz et al. [32]

2021

N = 115

Phase II safety and efficacy study [whole gland treatment] [multi-center]

-45–80 years old

-T2b or less

-GG 1-2

-PSA < 15 ng/mL

-minimum 10 core biopsy

-no previous treatment

GG1: 43 (37%)

GG2: 69 (60%)

GG3: 3 (3%)

12 months

-12 grade 3 adverse events occurred in 9 patients, all resolved by 12 months

-no grade 4 events, rectal injuries, severe incontinence, or sever erectile dysfunction

-median PSA decreased from 6.3 ng/mL at baseline to nadir of 0.34 ng/mL

-at 12 months, median PSA was stable at 0.5 ng/mL

-Of the 92 patients who were potent at baseline, 69 (75%) maintained or regained potency by 12 months

-At 12 months, less than 1% of patients were incontinent per EPIC-50

At 12 months, patients free of PCa:

-13/17 (76%) patients with baseline low volume GG1

-16/26 (14%) patients with baseline high volume GG1

-43/68 (63%) patients with baseline GG ≥ 2

-overall, 72/111 (65%) patients had no evidence of cancer

Ramsay et al. [33]

2017

N = 5

Proof of principle [treat and resect] study

[sectoral ablation] [single center]

-T1 or T2a PCa

-GS ≤ 7

-PSA < 15 ng/mL

Radical prostatectomy same day

Not reported

n/a

n/a

-Averaged temperature control accuracy -1.6 ± 4.8 °C

-Spatial target accuracy -1.5 mm ± 2.8 mm

-Average treatment accuracy -0.4 ± 1.7 mm

Anttinen et al. [35]

2020

N = 6 (8 MRI-visible, MRI-targeted biopsy confirmed lesions, PI-RADS ≥ 3)

Phase I safety and efficacy [treat and resect] study

[sectoral ablation]

[single center]

-Median age 70 yrs

-Median PSA = 8.9 ng/mL

GS 6 (3 + 3): 1 (17%)

GS 7 (3 + 4): 2 (33%)

GS 7 (4 + 3): 2 (33%)

GS 8 (4 + 4): 1 (17%)

3 weeks

No treatment related complications

-not analyzed by authors

-No difference in quality of life outcomes (IPSS, IIEF-5, UCLA-PCI-UFI, ICIQ-SF, and EPIC26-BD) between baseline and 3 weeks post-TULSA

At 3 weeks:

-Target ablations were successful in all patients, with target treatment volumes of 7-19 mL

-At prostatectomy, histopathology demonstrated no viable malignancy within the ablated targets

-4/6 (67%) patients had residual cancer outside of the planned ablation volume, inside the pre-planned 3 mm safety margin near the NVB at the prostate capsule

Anttinen et al. [35]

2020

N = 11

Phase I safety and efficacy study [Salvage treatment] [single center]

-localized, histopathologically verified, radiorecurrent PCa

-median age 69 years

-9 patients received external beam RT

-1 patient received high dose rate brachytherapy

-1 patient received external beam RT and second-line salvage high dose rate brachytherapy

12 months

-1 grade 3 adverse events

-3 grade 2 adverse event, related to urinary retention and infection

-at 12 months, 10 patients were free of catheterization; 1 patient who received prior salvage brachytherapy remained on intermittent catheterization

-no urethral strictures, rectal injuries, or post-TULSA fistulas

-Median PSA decreased from 7.6 ng/mL at baseline to nadir of 0.2 ng/mL and was 0.23 ng/mL at 12 months

-All patients had severe erectile dysfunction (per IIEF-5) at the time of study enrollment

-Reduction in EPIC-26 irritative/obstructive domain scores from median 94 at baseline to 75 at 12 months

At 12 months:

10/11 (91%) patients were free of PCa in the targeted ablation zone, confirmed on imaging and biopsy

-2 out of field recurrence detected on PSMA-1007 PET-CT

-1/11 (9%) in field recurrence detected on PSMA-1007 PET-CT, located at the periphery of the ablated region