Hypofractionated, Dose Escalation Radiotherapy for High Risk Adenocarcinoma of the Prostate

Summary

In North America, around a quarter a million men are diagnosed with prostate cancer every year, and about 31,000 patients will die of their disease each year. Like other western countries, the incidence in Canada has increased due to an aging population and prostate specific antigen (PSA) screening. This has led to a significant demand on cancer care services for these patients. Prostate cancer patient with high risk features are more often treated with external beam radiation therapy (EBRT) plus two to three years of hormonal manipulation (luteinizing hormone-releasing hormone \[LHRH\] agonist). The most common radiation dose treatment for these patients is 74-78 Gy in 37-39 daily fractions of 180-200 cGy for a treatment length of 7.5 weeks. This fraction size is believed to offer the best balance between desired tumour kill and unwanted normal tissue injury. Larger fraction sizes of more than 250 cGy (hypofractionation) are usually avoided for curative therapy because late reacting normal tissues. However prostate cancer cells have a unique radiobiology characteristic that suggests that hypofractionated radiotherapy is more efficient at prostate tumour killing than standard fractionation is, and will produce equivalent tumour control with a lower total dose and a shorter overall treatment time. Improved target localization techniques and conformal radiation therapy technology have allowed for dose escalation and hypofractionated radiation delivery in these circumstances with minimal or no increased toxicities.

This trial is designed to determine whether high risk prostate cancer patients can be safely treated with a dose escalation hypofractionated radiation therapy in 5 weeks as opposed to the usual 7-8 weeks. These patients will be randomized to either the usual 76 Gy in 38 fractions or 68 Gy in 25 fractions. 3D-Conformal Radiotherapy (3D-CRT) or Intensity Modulated Radiotherapy (IMRT) will be used to deliver the required radiation dose. Patients will also receive 28 months of androgen deprivation therapy (LHRH agonist). The primary outcome of the study is the acute and delayed toxicity and the secondary outcomes include biochemical failure, prostate specific mortality rate, bone metastases free survival, the prognostic and predictive value of several biological variables: presence of the PTEN deletion; expression of FoxP3 gene variants, topoisomerase 2α and cancer testis antigens; expression of X chromosome-linked micro-RNAs; presence of TMRSS2-ERG gene fusion and quality of life. It is planned to recruit 250 patients to this study.

Conditions

• Prostate Cancer

Interventions

RADIATION

hypofractionation

Centres using IMRT will use the dose painting technique to treat the prostate + proximal 1-cm SV to 6800 cGy in 25 fractions while the pelvic lymph nodes will receive 4500 cGy in 25 fractions. For patients with T3b, the whole SV is to be treated to 6800 cGy. Institutions using 3D-CRT will deliver the required dose to the pelvic volume (including pelvic lymph nodes and boost volume) - 4500 cGy - and a concomitant boost to the prostate and proximal 1-cm (or the whole SV if involved) SV to 6800 cGy.

RADIATION

conventional

The first phase: whole pelvis including the prostate and regional lymph nodes treated with 4400 cGy in 22 fractions. The second phase: prostate + proximal 1-cm SV treated with 3200 cGy in 16 fractions. For patients with T3b, the whole SV is to be treated to 7600 cGy.

Sponsors & Collaborators

• Sir Mortimer B. Davis - Jewish General Hospital

  lead OTHER

Principal Investigators

• Tamim Niazi, MD · Jewish General Hospital

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

MALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2012-01-31

Primary Completion

2026-01-31

Completion

2026-01-31

Countries

• Canada

Study Locations