Risk for ED at up to 12 weeks after a systematic TRUS-guided prostate biopsy


There is nothing very new about the idea that prostate biopsies can affect erectile function in some patients (although we still have very little knowledge of about exactly why this occurs). We have had clear evidence that this effect can occur since 2001. What has been less clear is exactly how common this effect is, whether it is more common in certain categories of patient, and how long it may last after the biopsy in definable sets of patients.

In a paper by Murray et al. in the November issue of BJU International, the authors have reported the results of a prospective study of erectile function before and after transrectal ultrasound (TRUS)-guided biopsy (at which a minimum of 12 systematic biopsy cores were taken together with additional cores that might be indicated based on clinical or imaging data). The biopsies were all carried out at a single academic medical center between January 2011 and March 2013 according to a pre-approved protocol, but they were done by a number of different urologists.

Immediately prior to the biopsy, each patient was asked to complete the five-item version of the International Index of Erectile Function (IIEF-5) questionnaire as well as another questionnaire. The patients were also asked to repeat completion of these questionnaires at 1, 4, and 12 weeks after their biopsies.

Here are the key findings reported by Murray and her colleagues:

  • 220 patients were initially enrolled into the study.
  • At enrollment these 220 patients had
    • An average (mean) age of 64.1 years (range, 45 to 86 years)
    • An average (mean) PSA level of 6.7 ± 0.65 ng/ml
  • At baseline (when all 220 patients completed the questionnaires)
    • 36.6 percent of patients reported no erectile dysfunction (ED), with an IIEF-5 score of 22 to 25.
    • 22.3 percent of patients reported mild ED, with an IEEF-5 score of 17 to 21.
    • 15.5 percent of patients reported mild to moderate ED, with an IIEF-5 score of 12 to 16.
    • 10.0 percent of patients reported moderate ED, with an IIEF-5 score of 8 to 11.
    • 13e.6 percent of patients reported severe ED, with an IIEF-5 score of 5 to 7.
  • At 1 week of follow-up (when 163 patients completed and returned the questionnaires)
    • 29/85 patients (34 percent) who had no ED at baseline had a decreased IIEF-5 score (i.e., an increase in their ED).
    • 1/85 patients who had no ED at baseline reported severe ED at 1 week of follow-up.
    • The average (mean) IIEF-5 score for these 163 patients had dropped from 18.2 at baseline to 15.5 (P < 0.001).
  • At 4 weeks of follow-up (when 126 patients completed and returned the questionnaires)
    • 17 patients (20 percent) who had no ED at baseline had a decreased IIEF-5 score.
    • The average (mean) IIEF-5 score for these 126 patients had dropped from 18.4 at baseline to 17.3 (P = 0.008).
  • At 12 weeks of follow-up (when 103 patients completed and returned the questionnaires)
    • 20 patients (24 percent) who had no ED at baseline had a decreased IIEF-5 score
    • The average (mean) IIEF-5 score for these 103 patients had dropped from 18.4 at baseline to 16.9 (P = 0.004).

The authors were also able to show that:

  • For the patients who had had a prior biopsy before the current biopsy,
    • The average (mean) IIEF-5 score at 1 week of follow-up dropped from 18.3 at baseline to 15,4 (P < 0.001).
    • There was no significant change in IIEF-5 score at 4 or 12 weeks of follow-up compared baseline.
  • For the patients who had not had a prior biopsy before the current biopsy,
    • The average (mean) IIEF-5 score at 1 week of follow-up dropped from 18.4 at baseline to 15.5 (P < 0.001).
    • There was no significant change in IIEF-5 score at 4 weeks of follow-up compared baseline.
    • The average (mean) IIEF-5 score at 12 weeks of follow-up dropped from 18.0 at baseline to 16.4 (P = 0.014).
  • For the  patients who were diagnosed with prostate cancer at the current biopsy,
    • The average (mean) IIEF-5 score at 1 week of follow-up dropped from 18.4 at baseline to 15.5 (P < 0.001).
    • There was no significant change in IIEF-5 score  at 4 weeks of follow-up compared baseline.
    • The average (mean) IIEF-5 score at 12 weeks of follow-up dropped from 18.1 at baseline to 14.7 (P = 0.001).
  • For the  patients who were not diagnosed with prostate cancer at the current biopsy,
    • The average (mean) IIEF-5 score at 1 week of follow-up dropped from 18.1 at baseline to 15.4 (P < 0.001).
    • There was no significant change in IIEF-5 score at 4 or 14 weeks of follow-up compared baseline.
  • For the patients who were < 60 years of age at the time of the current biopsy,
    • The average (mean) IIEF-5 score at 1 week of follow-up dropped from 20.7 at baseline to 18.7 (P = 0.015).
    • There was no significant change in IIEF-5 score at 4 or 12 weeks of follow-up compared baseline.
  • For the patients who were ≥ 60 years of age at the time of the current biopsy,
    • The average (mean) IIEF-5 score at 1 week of follow-up dropped from 17.3 at baseline to 14.1 (P < 0.001).
    • The average (mean) IIEF-5 score at 4 weeks of follow-up dropped from 17.5 at baseline to 16.3 (P = 0.024).
    • The average (mean) IIEF-5 score at 12 weeks of follow-up dropped from 17.8 at baseline to 16.0 (P = 0.005).

Murray et al. conclude that, in this study,

  • Most men who had a TRUS-guided biopsy had a significant decrease in IIEF-5 score that was independent of age, cancer diagnosis, and prior biopsy status.
  • This decrease in IIEF-5 score
    • Continued for up to 12 weeks in all patients and
    • Was particularly evident in men who had not had a prior biopsy and/or were diagnosed with prostate cancer and/or were ≥ 60 years of age
  • Men ≥ 60 years of age are predisposed to a higher risk for ED after a TRUS-guided biopsy than younger patients
  • Men scheduled for a TRUS-guided prostate biopsy should be counseled specifically about risk for acute or sub-acute ED prior to their biopsy (along with all the other known risks associated with prostate biopsy).

It is worth pointing out that, as far as the authors and your sitemaster are aware, this is the largest prospective study conducted to date on risk for ED associated with TRUS-guided biopsy that has used a validated questionnaire to collect relevant data. However, we repeat that why ED occurs in individual patients after prostate biopsy is unknown, but there are good non-physiological reasons to understand (at least in part) why ED might occur for a while after biopsy in men after a first prostate biopsy and/or after a diagnosis of prostate cancer — regardless of any physiological reasons that may also exist.

7 Responses

  1. Hi, Honey I’m home! They just told me I might have cancer! Let’s go make love!

  2. Yeah right, Honey … Now I’ve really got a headache! :O)

  3. And by the way, Honey, if I ejaculate it’s going to be bloody.

  4. I’m not sure why there is a complete mystery about the physiological cause of temporary ED post TRUS biopsy. In my simpleton mind, if the needle penetrates the prostate and the neurovascular bundle of nerves surrounds the prostate capsule in some places, then isn’t it reasonable to surmise that the needle could penetrate some of the nerves during the TRUS biopsy causing temporary changes in erectile function?

    I recall that within a few hours after my TRUS biopsy, I spontaneously (i.e., without physical or psychological stimulation) had a very hard erection for about 15 minutes. Likewise, the remnants of my neurovascular bundle of nerves post-RP are occasionally physically stimulated by a large bowel movement (by physical pressure applied to the nerves (?)). None of this is scientifically proven of course, but I don’t see why my analysis is so far fetched. Sitemaster, am I way off base here?

    Thanks.

    Richard

  5. Richard:

    Actual physical effects on specific tissues are undoubtedly one of many reasons why men may have loss of or changes in their erectile function after a biopsy … but it’s not as simple as just physical effects on the nerves in the neurovascular bundle. Indeed, ideally such nerves shouldn’t be penetrated at all during a well-conducted prostate biopsy.

    Quite apart from the strong possibility that there are other, as yet unidentified, physical effects of a biopsy on prostate-related tissues, there are also all of the potential psychological effects associated with having a biopsy. We men are highly sensitive the psychological effects of any type of intrusive effect on our genitalia. For some men, just having the biopsy (however well it is conducted) can be very painful physically or very “painful” emotionally and psychologically. In addition, if the biopsy comes back positive there is the entire psychological effect of having been diagnosed with cancer. … That’s quite enough to make sure (for at least some men) that they will have no interest in sex for weeks or months.

    Much as we may be able to identify specific causes for temporary or permanent loss of erectile function in some men after a biopsy, that doesn’t mean we can apply such a cause to all men. In that context it is worth remembering that there are rare prostate cancer patients who, after an orchiectomy, are still highly sexually active with excellent erectile function. It makes no sense whatsoever physiologically, but it is very definitely well documented.

  6. When I had my biopsy, at one point the nurse conducting it said, “This is going to cause tingling or pain in the end of your penis”, and sure enough it did.
    So there must be some nerve involvement, with what effect I don’t know.

  7. James:

    Quite apart from the nerves that run outside and over the prostate (in the neurovascular bundles that control erectile function), there are much smaller and finer nerves that run within the prostate itself and which are much more likely to be associated with the effects the nurse warned you of … but I am not an anatomist and so I cannot offer you a precise explanation.

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