Prostate Radiotherapy Comparing Moderate and Extreme Hypo-fractionation (PRIME Trial)

The standard duration of treatment with radiotherapy is 8 weeks in conventional fractionation; 5-6 weeks with moderate hypo-fractionation, while it is only 1- 2 weeks with extreme hypo-fractionation (SBRT).The health costs and out of pocket expenditure involved in the conventional hypo-fractionated radiotherapy treatment largely depends on the overall treatment duration. This involves expenditure not only for the patient but also the caretaker. Moreover most of these patients presenting to a tertiary care centre from different parts of the country, have logistic issues of accommodation, food, travel along with the treatment costs. Also for patients staying away from family, 5 weeks treatment without considerable family support has a psychological impact, especially on elderly group of patients commonly seen with prostate cancer.This further leads to a major cause of distress among these patients, especially in a resource limited setting as ours.

Extreme hypo-fractionation with a total duration of 2 weeks, would offer an opportunity to optimize the therapeutic ratio taking advantage of the potential therapeutic gain due to low alpha/beta for prostate to higher dose/fraction(compared to surrounding organs at risk). Moreover, shortened overall treatment time,would lead to less distressing and early recommencement of their daily activities for the patients,with an obvious impact in improving the quality of life and health costs.

Given the potential positive economic impact with shorter duration treatment with similar clinical outcomes and probable similar toxicity profile, SBRT (extreme hypo-fractionation) in prostate cancer is an attractive treatment option, especially in a limited-resource setting and can have a large and positive impact on the patient care.

Inclusion criteria

• Age: above 18 years.
• Participants must be histologically proven, adenocarcinoma prostate
• Localised to the prostate or pelvic lymph nodes
• High risk prostate cancer as defined by National Comprehensive Cancer Network (NCCN):Gleason score of 8-10, clinical stage T3a or higher, or PSA > 20 ng/mL.
• Ability to receive long term hormone therapy/ orchidectomy
• Karnofsky Performance Score (KPS) >70 (see appendix
• No prior history of therapeutic irradiation to pelvis
• Patient willing and reliable for follow-up and QOL.
• Signed study specific consent form

Exclusion criteria

• Evidence of distant metastasis at any time since presentation
• Life expectancy <2 year
• Previous RT to prostate or prostatectomy.
• A previous trans-urethral resection of the prostate (TURP)
• Severe urinary symptoms or with severe International Prostate Symptom Score (IPSS) score despite being on hormonal therapy for 6 months which in the opinion of the physician precludes RT
• Patients with known obstructive symptoms with stricture.
• Any contraindication to radiotherapy like inflammatory bowel disease.
• Uncontrolled comorbidities including, but not limited to diabetes or hypertension
• Unable to follow up or poor logistic or social support