Intermediate-risk PCa: Urinary complications lowest with brachytherapy

Apr 08, 2019

Among the treatment options for intermediate-risk prostate cancer, brachytherapy is associated with the lowest 10-year rate of severe urinary complications while radical prostatectomy most often resulted in the use of devices to treat erectile dysfunction, according to findings from a retrospective analysis of patients who underwent treatment between 2004 and 2007.

San Francisco-Among the treatment options for intermediate-risk prostate cancer, brachytherapy is associated with the lowest 10-year rate of severe urinary complications while radical prostatectomy (RP) most often resulted in the use of devices to treat erectile dysfunction, according to findings from a retrospective analysis of patients who underwent treatment between 2004 and 2007.

The data come from an examination of a Kaiser Permanente database of 1,503 patients with intermediate-risk prostate cancer who were treated with either RP (n=819), external beam radiation therapy (EBRT) (n=574), or brachytherapy using iodine-125 (n=110).

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Almost all patients (97%) in the database who underwent brachytherapy had prior assessment using the AUA score for urination, which may explain the low rate of urinary complications observed in this group, said lead investigator Barry W. Goy, MD, who presented the data at the Genitourinary Cancers Symposium in San Francisco.

“We know in general that brachytherapy causes more urinary irritative symptoms and can cause some degree of retention if you implant patients with moderately obstructive uropathy,” said Dr. Goy, of Southern California Permanente Medical Group, Los Angeles.

In contrast, only 11.5% of patients who underwent EBRT and 7.3% who underwent RP had a pretreatment assessment for urinary function using the AUA score.

Next: “From a urinary standpoint, I was expecting prostatectomy to be worse, and we found that prostatectomy and radiation were actually quite similar"“From a urinary standpoint, I was expecting prostatectomy to be worse, and we found that prostatectomy and radiation were actually quite similar,” Dr. Goy told Urology Times.

The 10-year rates of severe late genitourinary (GU) effects were 10.1% for RP, 12.5% for EBRT, and 4.0% for brachytherapy. Although the rate of GU complications associated with radiation was fairly low in the study, especially at 5 years, over 10 years some patients required incontinence pads or had post-void residual >100 cc, said Dr. Goy. “Some of those patients didn’t follow up with radiation oncology; they went straight to urology because some needed intermittent catheterization,” he said.

“We think that by doing an AUA score, you can better select patients who might be better suited for surgery or transurethral resection of the prostate followed by radiation versus the radiation options. Obtaining a pretreatment AUA score allows me to counsel patients more accurately about the percentages of severe complications.”

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Last year, his group used the same database to show that 10-year rates of freedom from biochemical failure were 82.0% for brachytherapy, 58.0% for radical prostatectomy, and 58.8% for EBRT (p<.0001). On multivariable analyses, brachytherapy remained an independent predictor for improved freedom from biochemical failure (p=.049 vs. external beam radiation therapy, andp<.0001 vs. RP).

Urinary and rectal complications following RP were graded as severe if patients required ≥3 pads/diapers per day, chronic use of a condom catheter or penile clamp, daily self-catheterization, or placement of a sling or an artificial urinary sphincter, or patients developed rectal fistula/incontinence.

Complications for EBRT and brachytherapy were graded as severe if they were classified as grade 3 or 4 on the Radiation Therapy Oncology Group grading system for late effects.

Severe gastrointestinal late effects (fistula, incontinence, or colostomy) were experienced by 0.5%, 1.6%, and 0.0% of those who underwent RP, EBRT, and brachytherapy, respectively.

The prevalence of patients requiring injections, pumps, or penile implants for a diagnosis of erectile dysfunction (ED) was calculated after a minimum of 1 year of follow-up. Almost one fourth (24.3%) of patients who underwent RP required ED devices, compared with 6.6% of those who had EBRT and 8.2% who had brachytherapy.