AB102. Efficacy and safety of prostate biopsy at 12 points by 16 G puncture needle

Objective: To investigate the efficacy and safety of transrectal prostate biopsy at 12 points by 16 G puncture needle under ultrasonic guidance.

Methods: One hundred cases of transrectal prostate biopsy patients under ultrasonic guidance were screened from urinary surgery of our hospital. They were taken as the research objects. All patients were in accordance with “disease diagnosis and treatment guidelines of China urinary surgery [2011]” and the operation indication of prostate biopsy. All patients were fully informed of the experiment, signed the informed consent and operation informed consent. They were highly suspected for suffering from prostate cancer. All patients were randomly divided into experimental group and control group using random number table method, with 50 cases in each group. 16 G puncture needle was adopted in patients of experimental group and conventional 18 G puncture needle was adopted in control group. Two groups of patients were divided into small volume subgroup (<40 mL), middle volume group (40-60 mL) and large volume group (>60 mL).Then they were divided into low level subgroup (4.1-10.0 ng/mL) and high level subgroup (>10.1 ng/mL) according to the level of PSA, A subgroup (D >0.15) and B subgroup (D <0.15) according to the level of PSAD. All patients’ puncture was performed by a full-time doctor. The operation was performed under epidural anesthesia. The tissue sampling was drawn by the routine 12 puncture needle. The length of needle was more than 11.9 mm and remained roughly consistent. HE staining was performed after puncture biopsy. The positive rate of biopsy was observed. All patients were treated with perioperative anti-infection and analgesic drug according to the state of illness. The postoperative pain degree, infection, hematuria and other complications of patients in two groups were recorded and evaluated.

Results: The success rates of needle biopsy were compared between patients in two groups. The prostate lesion tissue slice was bulky by 16 G puncture needle in experimental group. And the success rate of needle targeted biopsy was 37.5% (15/40). The prostate lesion tissue slice was bulky by 18 G puncture needle in control group. And the success rate of needle targeted biopsy was 15% (6/40). χ²=5.23, P<0.05. The success rates of needle targeted biopsy in patients of two groups showed significantly statistical significance. The total positive rates were compared between patients in two groups. There were 18 cases of prostatic cancer patients detected in experimental group (18/50, 36%). The total coincidence rate was 36%; There were 12 cases of prostatic cancer patients detected in control group (12/50, 24%). The total coincidence rate was 24%; χ²=1.19, P>0.05. The overall positive rates and coincidence rates showed no significantly statistical significance. Volume subgroup examination result: there were seven cases of small subgroup (7/12, 58.33%), six cases of middle volume subgroup (6/17, 35.29%) and five cases of large volume subgroup (5/21, 23.81%) detected by 16 G puncture needle. There were four cases of small volume subgroup (4/15, 26.67%), three cases of middle volume subgroup (3/12, 25%) and five cases of large volume subgroup (5/23, 21.74%) by 18 G puncture needle. The results of small, middle and large subgroups were χ²=1.14, χ²=0.03 and χ²=0.04. The detection rates showed no significant difference between all subgroups. P>0.05, which showed no statistical significance; the subgroup analysis showed that the overall detection rate of prostate cancer in large volume subgroup was lower than those of middle and small volume subgroups. The experimental group P=0.042, control group P=0.0042. P<0.05, which had statistical significance. Subgroup PSA examination results showed the detection rates of patients in all subgroups in experimental group and control group. The high level group: χ²=0.39, χ=1.34, P>0.05, which had no significantly statistical difference; however subgroup analysis showed that the detection rate of prostate cancer in overall PSA low level subgroup was lower than that of high level group. The experimental group: χ²=4.95, the control group χ²=7.67, P<0.05. The difference had statistically significance. PASD subgroup examination result showed the detection rates in relative PASD subgroups in experimental group and control group. A subgroup: χ²=1.11, B subgroup: χ²=0.36, P>0.05, which had no significantly statistical difference. However subgroup analysis showed that the detection rate in PASD A group was lower than that of PASD B group. The experimental group: χ²=5.97. The control group: χ²=5.02, P<0.05. The difference had statistical significance. Postoperative pain VAS visual analogue scale and the incidence rates of hematuria, infection and other complications results showed that there was no significant difference between experimental group and control group. χ²=0.05, P>0.05, which had no statistical significance.

Conclusions: 16 G needle can effectively improve the targeted detection rate. 18 G more used in conventional systematic biopsy.

Keywords: Prostate; biopsy; cancer