Stereotactic Radiotherapy of Prostate Cancer With Reduction of Safety Margins

University Hospital Ostrava

Status

Enrolling

Conditions

Prostate Cancer (Adenocarcinoma)

Treatments

Procedure: Stereotactic radiotherapy

Study type

Interventional

Funder types

Other

Identifiers

NCT06665932

16/RVO-FNOs/2024 (Other Grant/Funding Number)

ONK-11-SBRT

Details and patient eligibility

About

The study aims to reduce the PTV (Planning Target Volume) safety margins to 1-2 mm in stereotactic prostate radiotherapy for low- and medium-risk prostate cancers while maintaining a dose of 36.25 Gy in 5 fractions per day. By reducing the hems, the investigators expect a reduction of acute and late toxicity on the organs at risk, dominantly the urethra, bladder, penile bulb, and rectum, and an improvement in the quality of life.

Full description

In this prospective study, a total of 100 patients will be treated over 2 years. Patients will be implanted with 4 contrast markers (fiducials) in the prostate - in the base, apex, and right and left lobes of the prostate. Subsequently, 3 planning examinations will be performed: 1. CT with a urinary catheter immediately after the implantation of fiducials (gold contrast markers), with a distance from implantation 2. planning CT and MR without a urinary catheter. The CTV (Clinical Target Volume) will be defined by the prostate, and the border on the PTV will be reduced from 3-5 mm to 1-2 mm isometrically to maximize the reduction of doses to the organs at risk (rectum, bladder, and urethra, penile bulb, testes), the organs at risk (OAR) will be marked in the radiation plan as OAR. Subsequently, the patients will be irradiated with a dose of 36.25 Gy in 5 fractions per day. Acute toxicity will be evaluated in the 1st and 3rd month after radiotherapy, and late toxicity after 4-6 months according to CTCAE criteria (Common Terminology Criteria for Adverse Events).

Enrollment

100 estimated patients

Sex

Male

Ages

18+ years old

Volunteers

No Healthy Volunteers

Inclusion criteria

histologically verified, localized prostate cancer without regional lymphadenopathy or distant metastases
low or intermediate risk - favorable risk
staging according to NCCN recommendations:
low risk: no staging required
intermediate risk- favorable risk: CT abdomen and pelvis
PSA up to 15
age over 18 years
signed informed consent form
suitable position of fiducials (to be determined by the physicist)

Exclusion criteria

a histological type other than acinar adenocarcinoma
the presence of local lymphadenopathy or distant metastases
a dominant lesion in the periphery that is in contact with the capsule or grows through it
PSA over 15
unsatisfactory position of fiducials (to be determined by the physicist)
previous treatment with radiotherapy to the pelvic area