Lidocaine suppositories for prostate biopsy

Authors


Klaus G. Fink, Urology, Salzburger Landeskliniken, Paracelsus Private Medical University, Salzburg, Austria.
e-mail: k.g.fink@salk.at

Abstract

OBJECTIVES

To evaluate, in a randomized prospective study, the efficiency of transrectal lidocaine suppositories to reduce pain during transrectal prostate biopsy, as suppositories allow longer for the agent to be effective.

PATIENTS AND METHODS

In all, 100 patients were randomized to receive either a placebo suppository or 10 mL of 2% (200 mg) lidocaine gel rectally 10 min before biopsy, or a suppository containing 60 mg lidocaine 1 or 2 h before biopsy. Costs (in euros) per application were 0.82 for gel and 0.63 for suppositories. In all patients the same 10-core biopsy technique was used. Pain was evaluated using a visual linear pain scale ranging from 0 to 100 points; the patient's side of the scale did not show the number of points.

RESULTS

The mean pain scores in the placebo, lidocaine gel, and lidocaine suppositories applied 1 h and 2 h before biopsy were 36.2, 40.9, 29.2 and 21.2, respectively. Thus patients with no anaesthesia reported 25% more pain than those receiving lidocaine suppositories 1 h before and 71% more pain than those receiving lidocaine suppositories 2 h before biopsy (P = 0.002).

CONCLUSIONS

Lidocaine suppositories at a lower dose and with longer to take effect can be used to reduce pain significantly more effectively than the commonly used gel. As suppositories are easy to use and cheap, they are recommended in daily routine prostate biopsy.

INTRODUCTION

Transrectal prostate biopsy has become the standard procedure to diagnose prostate cancer. Usually urologists consider that the discomfort associated with the procedure is so mild and insignificant that the biopsy is taken with no anaesthesia [1]. For many years the sextant biopsy was the standard but currently the trend is to take 10 or more cores in one biopsy session. This is important, as pain increases with the number of cores taken. There is no doubt that a periprostatic nerve block is an efficient technique to minimize pain, as described by Soloway [2] in an editorial, but based on a survey by Davis et al.[3] only a few urologists are using it. Thus it seems that there is a need for a simple method of pain reduction for transrectal prostate biopsy. We evaluated the pain levels associated with the procedure and studied the feasibility of administering lidocaine as a suppository, in a randomized study that included a placebo, standard lidocaine gel and suppositories with two different application times before biopsy for the lidocaine to take effect.

PATIENTS AND METHODS

Indications for prostate biopsy included an abnormal DRE and/or an elevated serum PSA level. Men with an abnormal sensitivity to pain, e.g. with neurological conditions, anal fissures or strictures, prostatitis or prostatodynia, were excluded from the study. We also excluded men on analgesic medication, to minimize any potential influence on pain perception.

The consecutive patients scheduled for prostate biopsy were randomized by a nurse to one of four groups, using a randomization list generated using a commercially available computer program (DatInf GmbH, Tübingen, free download for Universities and non-commercial users). Group 1 was given a placebo suppository 1 or 2 h before biopsy; in group 2, patients received 10 mL of gel (Cathejell, Montavit, Austria) containing 2% (total 200 mg) lidocaine intrarectally, and as described by Issa et al.[1] and Chang et al.[4], 10 min was chosen to allow the gel to take effect; patients in group 3 and 4 received a suppository containing 60 mg lidocaine 1 h or 2 h before biopsy, respectively. The gel cost (in euros) was 20.61 for 25 doses (0.82 each) and the suppositories were custom-made by our pharmacy for 6.3 per 10 (0.63 each).

The patient and the urologists taking the biopsy were unaware of which group the patient was in, except for group 2. All groups also received 500 mg of ciprofloxacin twice a day, starting the day before biopsy and ending 3 days afterward. The prostate biopsy was taken under TRUS guidance using a 7 MHz transrectal probe, with 10 cores taken in all patients, from the apex, mid and base of the lobe, and from the lateral part of the prostate [5]. This is the standard biopsy technique in our department for patients having a first biopsy. If a patient requires a second biopsy >10 cores would be taken and therefore such patients were excluded unless the first biopsy was >2 years earlier, when the patient was managed in the same way as for a first biopsy. We used an automatic spring-loaded biopsy gun and an 18 G needle with a 22-mm stroke length and 18-mm cutting length (Tru-Cut, CR Bard, Covington, USA).

Immediately after the procedure patients were asked to grade the discomfort or pain experienced during the procedure using a visual linear pain scale. The patient's side of the scale did not show the number of points but the doctor's side had a scale from 0 to 100 points.

The results were analysed statistically using commercial software, with a two-sided t-test powered to detect a difference in the means of 15 points (sd 15, 25 patients per group) at P < 0.05, with a statistical power of 93%.

RESULTS

The mean (range) age of the 100 patients was 65 (41–83) years, the PSA level 17.6  (1.37–326) ng/mL and the prostate volume 38 (15–85) mL; 35 patients had a DRE that was suspicious for prostate cancer, but there were no statistically significant differences in these variables and the pain score.

The mean pain scores in groups 1–4 were 36.2, 40.9 (13% difference not significant, P = 0.367), 29.2 and 21.2, respectively (Fig. 1). Thus patients with no anaesthesia had 25% more pain than those in group 3, and 71% more pain than those in group 4; this difference was significant (P = 0.039 and 0.002, respectively). The difference between group 3 and 4 was 38% and also significant (P = 0.042).

Figure 1.


Study flow chart and pain score results.

Eight men in group 1 and nine in group 2 had pain during prostate biopsy that was perceived as severe, with a pain score of ≥ 50 (scale 0–100); only four men in group 3 and none in group 4 reported a pain score of ≥ 50. The difference in pain scored as ≥ 50 between group 1 or 2 and group 3 was not significant (P = 0.10 and 0.17, respectively), but that between group 1 or 2 and group 4 was significant (P = 0.003 and 0.001, respectively).

DISCUSSION

When urologists are meeting with patients beforehand, the procedure of transrectal prostate biopsy is usually described as uncomfortable. Urologists mostly consider that the discomfort associated with biopsy is so insignificant that the biopsy is taken with no anaesthesia [1]. Collins et al.[6] investigated pain and patients’ acceptance of TRUS-guided prostate biopsy, reporting that up to 90% of men found the procedure to be painful. In the present study, 25 men had a placebo for their biopsy and eight (32%) reported severe pain, defined as a pain score of ≥ 50 points on the scale used.

The periprostatic nerve block is undoubtedly an efficient way of minimizing pain [2], but the survey by Davis et al.[3], undertaken among community urologists in Florida and academic centres across the USA, showed that half of urologists do not recommend any type of anaesthesia and only 11% were using a periprostatic nerve block. Although they did not ask why there was such a low frequency of the use of anaesthetics, it seems that there is a need for a simple method of pain reduction for transrectal prostate biopsy.

Pain and discomfort associated with the procedure is caused by penetrating the anus with the ultrasound probe, penetrating the rectal wall with the needle, penetrating periprostatic tissue and prostatic wall, and finally the entry of the needle on firing the automated biopsy gun. As the rectal wall is a good medium for drug absorption an anaesthetic drug delivered into the rectum should reduce the pain perceived from a prostatic biopsy.

Lidocaine gel administered 10 min before biopsy was described previously, but the data were controversial. Issa et al.[1] reported a randomized study evaluating lidocaine gel; 25 men had 10 mL of 2% lidocaine gel at a total dose of 200 mg and 25 men did not. The mean pain score on a 10-point linear visual scale was 2 for the lidocaine group and 5 for the control group. In the study by Chang et al.[4], 108 men were randomized to receive either intrarectal lidocaine gel at the same dose, or lubricant alone. The only significant result in that study was that younger men had more pain. There was no significant therapeutic effect for lidocaine gel. In the present study the mean pain score in group 1 (placebo) was 36.2, and that in group 2 (lidocaine gel) was 40.9, 13% higher; this result was surprising, although the difference was not statistically significant.

Diffusion through the rectal wall depends on time and dose; it seems reasonable that a longer interval between delivering the agent and taking the biopsy would benefit the patient. Proctologists in Germany use suppositories containing lidocaine at a lower dose, but with a longer interval between delivering the drug and performing small procedures like excising haemorrhoidal nodules. We have evaluated the efficacy for prostate biopsy of administering 60 mg of lidocaine via suppositories 1 and 2 h before biopsy. Patients with no anaesthesia had 25% more pain than those in group 3 and 71% more than those in group 4; the differences in pain perception between men receiving suppositories or lidocaine gel were even higher. Thus suppositories are significantly better than gel, whether administered 1 or 2 h before biopsy, but the difference between 1 and 2 h was also significant.

To our knowledge this is the first report of using different applications of intrarectal lidocaine and different times for the drug to take effect. We did not include periprostatic injection in the study; there is ample evidence that periprostatic nerve block is effective for reducing pain during prostate biopsy [2,7] and therefore we are currently conducting a randomized trial comparing periprostatic nerve block and lidocaine suppositories.

The current European Association of Urology guidelines on prostate cancer state that the need for some form of anaesthesia is increasingly evident, as the current trend is to take more extensive biopsies [7]. Suppositories are cheap, easy to use and can be self-administered by the patient at a scheduled time. Based on our experience we recommend the use of lidocaine suppositories instead of lidocaine gel in routine biopsy.

In conclusion, lidocaine suppositories at a lower dose and with longer to take effect can be used to reduce pain on biopsy significantly better than the commonly used lidocaine gel. As suppositories are easy to handle and cheap, they are recommended for routine prostate biopsy.

CONFLICT OF INTEREST

None declared.

Ancillary