Comparison between low and high dose brachytherapy followed by radiation in prostate cancer

The authors aimed to compare urinary symptoms in men with localized prostate cancer treated with either low-dose or high-dose rate brachytherapy in combination with radiation therapy.

The authors concluded the both low-dose and high-dose brachytherapy with IMRT was safe and well-tolerated by patients. However, it took longer to recover from low-dose treatments than high-dose treatments. This was possibly due to an early show of symptoms and an earlier recovery time following high-dose treatment.

Localized prostate cancer is cancer that is contained within the prostate gland. Treatments such as brachytherapy and radiation therapy can be used to treat this type of cancer. Brachytherapy treats prostate cancer by inserting a radioactive implant device into the cancer tissue. It can be administered as a low-dose (several days or longer) or high-dose (for a few minutes) treatment, depending on the length of time the radioactive implant remains in the cancer tissue. Radiation therapy uses high-energy radiation beams to target, shrink and kill cancer. Intensity-modulated radiation therapy (IMRT) is a form of radiation that delivers treatment to tumors with minimal damage to surrounding tissues.

Urinary symptoms can occur after these treatments. These can include problems such as pain, inability to urinate, or bloating and severe pain in the lower abdomen. It is not clear what symptoms high-dose versus low-dose brachytherapy may cause. 

The aim of this study was to determine urinary symptoms in men with prostate cancer when treated with low-dose or high-dose rate brachytherapy in combination with IMRT.

16 patients in group 1 were treated with low-dose brachytherapy and IMRT. The average follow-up time was 1,070.5 days. 22 patients in group 2 were treated with high-dose brachytherapy and IMRT. The average follow-up time was 1,048.5 days. Patients completed the IPSS (a questionnaire used to measure urinary symptoms) both before and after treatment. The IPSS included questions on bladder obstruction symptoms (such as difficulty or weak urination) and irritative symptoms (urinary frequency and urge).

The IPSS score was higher (more symptoms reported) in group 1 than in group 2 during days 91–270. Irritative symptoms were also higher during days 91–360.

The recovery time for symptoms in group 1 was 181–270 days. This was roughly 90 days longer than recover time for group 2 (91–180).

The authors concluded the both low-dose and high-dose brachytherapy with IMRT was safe and well-tolerated by patients. However, it took longer to recover from low-dose treatments than high-dose treatments. This was possibly due to an early show of symptoms and an earlier recovery time following high-dose treatment.