A single-arm clinical trial on ultra-hypofractionated radiotherapy using an MR linear accelerator for prostate cancer with preserved sexual function (SMART pro II study)

A single-arm clinical trial on ultra-hypofractionated radiotherapy using an MR linear accelerator for prostate cancer with preserved sexual function - SMART pro II study

Status

Active, not recruiting

Phases

Unknown

Study type

Interventional

Source

JPRN

Registry ID

JPRN-UMIN000061315

Enrollment

Registered

2026-04-23

Start date

2026-05-01

Completion date

Unknown

Last updated

2026-06-29

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

prostate cancer

Interventions

The dose will be 13 Gy per session, for a total of two sessions, resulting in a total dose of 26 Gy. The dose prescription will be set so that 95% of the CTV (urethra + 1 mm) is irradiated at a dose o

26.0 Gy, V24.7 Gy &lt

60%, V23.4 Gy &lt

70%, V19.5 Gy &lt

90% Penile bulb: D50 &lt

15 Gy Cavernosus: D0.1 cc &lt

12 Gy Internal pudendal artery: D0.1 cc &lt

14 Gy

Eligibility

Sex/Gender

Male

Inclusion criteria

Inclusion criteria: (1) Risk classification according to NCCN guidelines: very low to favorable intermediate (2) Strong desire for preservation of sexual function and ECOG PS: 0-1 (3) Eligible for treatment with MR linear accelerator (4) No lymph node or distant metastasis on imaging (5) No history of smoking, or has quit smoking (6) Well-controlled diabetes (HbA1c < 7.0%)

Exclusion criteria

Exclusion criteria: 1) Patients already receiving hormone therapy 2) Patients with a history of pelvic radiation therapy 3) Patients with a biopsy positivity rate of 33.3% or higher in both lobes 4) Patients with PI-RADS >=4 lesions within 5 mm of the NVB on both sides of the bilateral MRI before treatment 5) Patients with an EPIC combined sex score of 30 or less 6) Patients taking anticoagulants or antiplatelet drugs 7) Patients with psychosis or psychiatric symptoms who are deemed unable to participate in the study 8) Patients whom the principal investigator deems unsuitable for inclusion in the study

Design outcomes

Primary

Measure	Time frame
At 24 months post-treatment, is the average total score of the 13 items (out of 44 points) in questions 17-23 regarding sexual function within the EPIC score maintained at 80% of the average score before treatment?	—

Secondary

Measure	Time frame
Sexual function at 60 months (compared to pre-treatment) Biochemical recurrence-free rate (defined as an increase of Nadir +2 ng/ml or higher, according to the Phoenix definition of RTOG-ASTRO).	—

Countries

Japan

Contacts

Public ContactNoriyoshi Takahashi

Tohoku University Graduate School of Medicine Department of Radiation Oncology

noriyoshi.takahashi.e3@tohoku.ac.jp022-717-7312

Outcome results

None listed

Source: JPRN (via WHO ICTRP) · Data processed: Jul 3, 2026