Brachytherapy (Internal Radiation Therapy)
Brachytherapy is a form of internal radiation therapy where tiny radioactive seeds or temporary radiation sources are placed directly inside the prostate. This delivers a very high dose of radiation to the cancer while minimizing exposure to nearby organs like the bladder and rectum.
It is an effective, minimally invasive, curative treatment for many men with low- and intermediate-risk prostate cancer, and is sometimes combined with external beam radiation for higher-risk disease.
Types of Brachytherapy
1. Low-Dose Rate (LDR) Brachytherapy – “Seed Implant”
Permanent radioactive seeds are implanted into the prostate
Radiation is released slowly over weeks to months
Usually a one-time outpatient procedure
Most common for low-risk and some favourable intermediate-risk cancers
2. High-Dose Rate (HDR) Brachytherapy
Temporary catheters are placed in the prostate
A high-intensity radiation source is inserted for minutes, then removed
Often done in 1–2 sessions
Used for intermediate- and high-risk cancers, often combined with EBRT
What the Procedure Is Like
For LDR (Seeds)
Performed under spinal or general anesthesia
Ultrasound guides placement of 70–150 tiny seeds
Go home the same day
Seeds stay in place permanently, but radiation fades over time
Minimal downtime—many men return to normal activities within days
For HDR
Thin tubes are inserted into the prostate under anesthesia
The radiation source travels through the tubes briefly
Tubes are removed before you go home
Often combined with short-course EBRT for best results
Who Is a Good Candidate?
Brachytherapy is often recommended for:
Low-risk prostate cancer
Favourable intermediate-risk cancer
Men with a smaller prostate gland (large prostates may require shrinking with medication first)
Men who prefer a one-time treatment option
HDR brachytherapy may be used for:
Unfavourable intermediate-risk or high-risk cancer (with EBRT)
Boost therapy after external beam radiation
Advantages of Brachytherapy
Highly effective, with long-term cure rates similar to surgery and EBRT
Very targeted radiation, sparing healthy tissue
Minimal downtime
Convenient one-day (LDR) or short-course (HDR) treatment
Lower risk of bowel issues compared with external beam radiation
Suitable for men who want a non-surgical curative option
Possible Side Effects
Short-Term
Urinary urgency, frequency, or burning
Temporary difficulty urinating (more common with LDR seeds)
Perineal soreness (from needles or catheter placement)
Mild fatigue
Long-Term
Persistent urinary symptoms in some men
Urethral narrowing (rare)
Erectile dysfunction over time (similar risk to radiation therapy overall)
Very low risk of bowel issues compared with EBRT
Special Considerations for LDR Seeds
For a short time, men may be asked to avoid long close contact with pregnant women or young children, though seeds are low-power and safe
Rarely, a seed can pass during urination early on—usually harmless
Why Men Choose Brachytherapy
Single-day treatment
Strong evidence for long-term cure
Less disruption to daily life
Lower bowel side effects
Highly targeted approach
Many men find it helpful to speak with others who’ve had either seed implants or HDR therapy. Groups like PROSTAID Calgary offer insight into real-world experiences, recovery, and what to expect week by week.
✔ a caregiver-focused explanation