About one-third of men in a recent prostate cancer study received "mismatched" care, meaning their treatment plans didn't factor in pre-existing conditions such as urinary, bowel or sexual dysfunction, and may have worsened these conditions, researchers report.

The study was published online Monday, ahead of its Jan. 1 print publication date.

The primary authors, researchers at the Center for Outcomes Research at Massachusetts General Hospital Cancer Center, believe that patient embarrassment about these issues may be leading to inappropriate treatment. They feel men simply don't mention pre-existing conditions to their doctors before beginning cancer treatment and consequently may undergo procedures that can make their conditions worse.

"Prostate cancer patients experience the same fears and hard decisions as all cancer patients do, but prostate cancer treatment directly affects very personal things that most people aren't comfortable talking about — urinary, bowel and sexual function," James Talcott, lead author of the study, said in a release.

"In this case, however, having that information matters because the three major treatments available to patients have different patterns of potential side effects."

Standard treatment options for prostate cancer, though similar in effectiveness, often have very different side effects, which need to be discussed in conjunction with a patient's pre-existing conditions, the authors said.

External radiation to shrink a prostate tumour can lead to poor functioning of the bowel, brachytherapy — in which radioactive particles are implanted in the prostate gland — can lead to problems with urination, and surgery can lead to sexual problems.

Questionnaires the answer, authors say

The six-year study tracked 440 patients with early stage prostate cancer at four medical centres in Boston. The participants filled out questionnaires about their urinary, sexual and bowel problems before treatment and at 3, 12, 24 and 36 months.

Researchers also had access to participants' medical files.

They found that 89 per cent of the men enrolled in the study had some form of urinary, bowel or sexual issue before they began treatment for prostate cancer. Thirty per cent of the study participants had mismatched treatment.

"As expected, mismatched brachytherapy and external beam radiation therapy led to worsened urinary and bowel symptoms, respectively, and nerve-sparing radical prostatectomy did not improve outcomes after baseline sexual dysfunction," states the report.

The authors also found that watchful waiting, in which a patient is closely monitored but does not undergo treatment, was infrequent, even in cases where men had all three sets of pre-existing problems and any treatment would have had a negative impact on quality of life.

The authors called for improved communication between doctors and patients to prevent poor outcomes. They also suggested doctors encourage patients fill out a questionnaire before making treatment decisions to ensure the right treatments are being selected.