Ultrasound‐Guided Transperineal Versus Transrectal Prostate Aspiration Biopsy in Diagnosing Prostate Cancer

Abstract

Background

Ultrasound‐guided prostate biopsy is the standard method for the diagnosis of prostate cancer. However, the effect of the optimal puncture approach on diagnostic yield and patient outcomes remains controversial.

Objective

To compare the diagnostic effectiveness and clinical outcomes of ultrasound‐guided transperineal versus transrectal prostate aspiration biopsy in patients suspected of prostate cancer.

Methods

A retrospective analysis was conducted on 150 patients who underwent prostate biopsy at our hospital between February 2020 and August 2024. Patients were divided into transperineal (n = 62) and transrectal (n = 88) groups. Key outcomes including cancer detection rate, complications, pain (VAS), and negative emotions were compared, with p < .05 indicating a statistically significant difference.

Results

No significant difference was found between the transperineal and transrectal groups in the detection rates of prostate cancer (51.61% versus 43.18%), chronic prostatitis (12.90% versus 18.18%), or benign prostatic hyperplasia (35.48% versus 38.64%). Transperineal biopsy required longer puncture time (22.92 ± 2.02 min versus 19.70 ± 1.93 min), but resulted in fewer overall complications (20.97% versus 38.64%), lower post‐procedure pain scores (VAS: 2.82 ± 1.13 versus 3.68 ± 1.14), and lower anxiety (HAMA: 10.34 ± 1.29 versus 12.55 ± 1.44) and depression scores (HAMD: 10.33 ± 1.68 versus 12.90 ± 1.38).

Conclusion

Both ultrasound‐guided transperineal and transrectal prostate biopsies are effective diagnostic methods for prostate cancer. Transperineal biopsy offers advantages in reducing postoperative complications, pain, and negative emotional responses, supporting its preferential use in selected patients.

Abbreviations

HAMA

Hamilton Anxiety Scale

HAMD

Hamilton Depression Scale

PSA

prostate‐specific antigen

PSAD

prostate‐specific antigen density

PTBx

transperineal puncture biopsy

TRBx

transrectal prostate biopsy

VAS

Visual Analogue Scale

Prostate cancer is one of the most common malignant tumors of the male genitourinary system, and its incidence continues to rise globally, especially in older men. ¹ , ² As early symptoms of prostate cancer are not obvious, timely and effective diagnostic methods are crucial for improving patients' quality of life and prolonging their survival period. ³ , ⁴ The gold standard for diagnosis of prostate cancer is prostate biopsy and the accuracy of prostate biopsy directly translates to correct diagnosis and appropriate treatment of prostate cancer. ⁵ , ⁶ With the development of medical imaging technology, the 2 main methods being used in clinical practice for ultrasound guided prostate biopsy techniques are now transrectal biopsy and transperineal biopsy. ⁷ , ⁸

As a classic surgical method for the diagnosis of prostate cancer, transrectal prostate biopsy (TRBx) has long played an important role in clinical practice due to its convenient biopsy procedure, economic and practical characteristics. Although this technique has advantages in obtaining prostate tissue samples directly through the rectal wall, recent studies have found that it has several clinical limitations. Literature reports have shown that complications such as rectal bleeding or infection may occur with TRBx, ⁹ , ¹⁰ especially for patients with diabetes or immunocompromised patients, the risk of infection is particularly noteworthy. In addition, limited by the puncture angle, it is difficult for TRBx to fully obtain the tissue of the peripheral zone of the prostate, which may lead to missed diagnosis of clinically significant cancer foci and affect its detection rate. ¹¹ In addition, limited by the puncture angle, it is difficult for TRBx to fully obtain the tissue of the peripheral zone of the prostate, which may lead to missed diagnosis of clinically significant cancer foci and affect its detection rate. ¹²

Materials and Methods

Patients

One hundred and fifty prostate puncture biopsy patients admitted to our hospital from February 2020 to August 2024 were retrospectively selected for the study, and were divided into the transperineal group (62 cases) and the transrectal group (88 cases) according to the puncture method. All of the following criteria must be met for enrollment. Inclusion Criteria: (1) Meet the indications for prostate puncture biopsy and undergo initial prostate puncture biopsy; (2) Abnormal prostate‐specific antigen (PSA) or prostate‐specific antigen density (PSAD) values; (3) Suspicious nodules detected by imaging or rectal fingerprinting; (4) Completed clinical data. Exclusion criteria: (1) severe cardiopulmonary, cerebral or coagulation disorders; (2) recent lower urinary tract surgery and endocrine drug therapy; (3) systemic infections or coagulation disorders; (4) severe hemorrhoids, rectal or anal disorders; (5) infections or injuries at the site of the puncture; (6) communication disorders and psychiatric disorders; and (7) midway withdrawals or transfers to other hospitals. The study was approved by the Medical Ethics Committee of our hospital, and all patients and their families were informed and signed an informed consent form.

Preparation for Puncture

All patients received ancillary investigations such as routine blood, urine, blood coagulation, biochemistry, urine bacterial culture, routine stool, chest x‐ray, electrocardiogram, and magnetic resonance scanning of the prostate before puncture. It was confirmed that no aspirin, clopidogrel, or other related anticoagulant drugs were taken 1 week before the biopsy procedure. Hypertensive patients control blood pressure within 140/90 mmHg, and diabetic patients control blood glucose within 8 mmol/L. Urinary tract infection before puncture and other symptoms of urinary tract irritation disappeared after active treatment, and urine culture turned negative. Three days before the biopsy procedure, the transrectal group did bowel preparation, including oral metronidazole and gentamicin, and laxative or cleansing enema was taken the night before the biopsy procedure. Two hours before the biopsy procedure, prophylactic intravenous antibiotics were applied in the transrectal group and prophylactic oral antibiotics in the transperineal group. Before the puncture, try to calm the patient's emotion, reduce their nervousness and fear, and accept and cooperate with the biopsy procedure with a positive attitude.

Puncture Biopsy Procedure

Both groups were guided by a color ultrasound diagnostic machine (Toshiba, model: Aplio500) and punctured with a Bard automatic biopsy gun (Bard Inc., model: MG12‐22), with specimen slot lengths of 15 and 22 mm. The biopsy physicians were skilled in puncture, and the tissues were fixed with formalin and sent to the Department of Laboratory Medicine for histopathology.

Transrectal group: the patient was placed in a knee‐chest position on the left side with the back parallel to the operating bed. The anus was fully exposed, and the lower part of the rectum was disinfected at least 3 times by applying iodine‐vapor cotton balls, and the cotton balls were left in the lumen of the rectum, and the lower part of the rectum was disinfected 2 more times. The head of the ultrasound probe was coated with coupling agent and then put on a protective sleeve, installed with a transrectal puncture frame, placed into the rectum to observe the prostate image, adjusting the probe to align with the top, middle, and tip of the prostate at the posterior‐lateral part and the suspected lesion site. An 18G disposable biopsy needle was mounted and passed through the rectal wall under ultrasound guidance. The 12‐needle puncture method was used, with 2 needles at the base and middle of the prostate, 1 needle at the tip, and 1–3 needles at the prostate nodule or ultrasound abnormality. After the biopsy procedure was completed, the puncture site was pressed for 3–5 minutes, and the anus was stuffed with iodine‐vapor gauze to prevent bleeding. Transperineal group: patients were placed in the lithotomy position on the puncture table to fully expose the anus and perineum, 0.5% iodine was given to routinely disinfect the perianal and perineal areas and spread the towel, and 1% lidocaine injection was given to anaesthetize the rectal mucosa and perineum with local infiltration. The rectal ultrasound probe was coated with coupling agent and put on a protective sleeve and then sent into the rectum through the anus for systematic and comprehensive observation of prostate imaging. The probe angle and depth were adjusted as needed to visualize prostate volume, blood flow, nodule location, size and number. Determine the puncture site, install the 18G disposable biopsy puncture needle, from the perineal area skin puncture entry, the tip of the needle to reach the prostate peritoneum, press the puncture launch button. The 12‐needle puncture method was used, with 4 needles for each region and 1–3 needles at the prostate nodule or ultrasonic abnormality, and the perineal area was bandaged with gauze under pressure after the biopsy procedure to avoid bleeding. Within 3 days after the biopsy procedure, patients in both groups were given oral levofloxacin to fight infection.

Observation Indicators

(1) Prostate disease detection rate: prostatitis, benign prostatic hyperplasia, prostate cancer. (2) Intraoperative indicators: puncture time, number of puncture needles. (3) Occurrence of complications: urinary retention, bleeding, urethral distension, bloody stool, hematuria, dizziness, perineal swelling and pain, chest tightness, dysuria, fever. (4) Pain score: visual analogue scale (VAS) ¹³ was used to assess patients' pain on a scale ranging from 0 to 10. Prior to the assessment, patients were introduced to the scale in detail and were asked to choose the appropriate score according to their pain level, with 0 indicating no pain and 10 indicating severe pain, with the lower the score, the less severe the pain. (5) Negative mood scores: the Hamilton Anxiety Scale (HAMA) ¹⁴ and the Hamilton Depression Scale (HAMD) ¹⁵ were used to rate the patients' anxiety and depression, with higher scores being associated with more negative mood. All patients in this study were followed up for at least 30 days after puncture.

Statistical Analyses

Statistical analyses and plots were performed using GraphPad Prism 8.0. Measurement data were expressed as mean ± standard deviation, and t‐test was used for comparison between 2 groups. Count data were expressed as the number of instances (%), and comparisons between the 2 groups were made using the chi‐square test, and the continuity‐corrected chi‐square test was used when the theoretical frequency in the chi‐square test was less than 5. All analyses were 2‐sided, and p < .05 was considered a statistically significant difference.

Results

A total of 150 patients were enrolled, including 62 patients in the transperineal group and 88 patients in the transrectal group. There were no significant differences in baseline characteristics such as age, BMI, PSA level, prostate volume, comorbidities, preoperative medication, and urinary tract infection between the 2 groups (all p > .05) (Table 1). Pathological examination revealed 70 cases of prostate cancer, 24 cases of chronic prostatitis, and 56 cases of benign prostatic hyperplasia. The detection rates of prostate cancer (51.61% versus 43.18%, p = .394), chronic prostatitis (12.90% versus 18.18%, p = .521), and benign prostatic hyperplasia (35.48% versus 38.64%, p = .825) were comparable between the 2 groups (Table 2). Regarding intraoperative indicators, no significant difference was observed in the number of puncture needles between groups (p = .414). However, the puncture time was significantly longer in the transperineal group than in the transrectal group (22.92 ± 2.02 min versus 19.70 ± 1.93 min, p < .001) (Figure 1). The overall incidence of complications was significantly lower in the transperineal group compared with the transrectal group (20.97% versus 38.64%, p = .034) (Table 3). In terms of pain assessment, the VAS score before puncture was similar in the 2 groups (p > .05), but the VAS score after puncture in the transperineal group was significantly lower than that in the transrectal group (2.82 ± 1.13 versus 3.68 ± 1.14, p < .001) (Figure 2). Similarly, no significant differences were found in pre‐puncture HAMA and HAMD scores between groups (both p > .05). However, post‐puncture scores for both anxiety (10.34 ± 1.29 versus 12.55 ± 1.44, p < .001) and depression (10.33 ± 1.68 versus 12.90 ± 1.38, p < .001) were significantly lower in the transperineal group (Figure 3).

Table 1.

Comparison of General Data Between the 2 Groups [n (%), Mean ± SD]

Classification	Transrectal Group (n = 88)	Transperineal Group(n = 62)	χ2/t	p Value
Age (years old)	70.35 ± 7.45	70.66 ± 7.11	0.255	.799
BMI (kg/m2)	22.91 ± 1.95	23.15 ± 1.92	0.731	.466
PSA (ng/mL)
<10	6.76 ± 1.34	6.92 ± 1.33	0.294	.772
10–20	15.71 ± 2.08	14.92 ± 2.14	1.206	.235
>20	348.7 ± 334.7	242.7 ± 262.9	1.548	.125
Prostate volume (mL)	68.45 ± 25.53	62.81 ± 23.13	1.373	.172
Hypertensive	25 (28.41)	18 (29.03)	0.010	.920
Diabetes	5 (5.68)	2 (3.23)	0.096	.757
Hypertensive + Diabetes	10 (11.36)	6 (9.68)	0.025	.875
Preoperative anticoagulants	1 (1.14)	0 (0.00)	0.023	.878
Preoperative indwelling urinary catheter	1 (1.14)	1 (1.61)	0.253	.615
Preoperative urinary tract infection	2 (2.27)	2 (3.23)	0.042	.839

Table 2.

Comparison of Diagnostic Results Between the 2 Groups [n (%)]

Classification	Prostate Cancer	Chronic Prostatitis	Benign Prostatic Hyperplasia
Transrectal group (n = 88)	38 (43.18)	16 (18.18)	34 (38.64)
Transperineal group (n = 62)	32 (51.61)	8 (12.90)	22 (35.48)
χ2	0.728	0.413	0.049
p value	0.394	0.521	0.825

Figure 1.

Comparison of intraoperative indicators between the 2 groups of patients. A, Number of puncture needles; B, puncture time; ***p < .001.

Table 3.

Comparison of Complications Between the 2 Groups [n (%)]

Classification	Transrectal Group (n = 88)	Transperineal Group(n = 62)	χ2	p Value
Urine retention	1 (1.14)	0 (0.00)
Hemorrhage	2 (2.27)	0 (0.00)
Painful urethral swelling	4 (4.55)	3 (4.84)
Urinary tract infection	8 (9.09)	4 (6.45)
Bloody stool	6 (6.82)	0 (0.00)
Hematuria	9 (10.23)	4 (6.45)
Dizzy	1 (1.14)	0 (0.00)
Perineal swelling	0 (0.00)	1 (1.61)
Chest distress	1 (1.14)	0 (0.00)
Urination disorder	1 (1.14)	0 (0.00)
Feverish	1 (1.14)	1 (1.61)
Overall incidence	34 (38.64)	13 (20.97)	4.488	.034

Figure 2.

Comparison of pain levels between the 2 groups. VAS, visual analogue scale; ***p < .001.

Figure 3.

Comparison of negative emotions between the 2 groups. HAMA, Hamilton Anxiety Scale; HAMD, Hamilton Depression Scale; ***p < .001.

Discussion

The 6‐needle systematic approach, introduced in 1989, is considered the classic “gold standard” for prostate biopsy. ¹⁶ However, long‐term practice has found the method to be problematic in terms of missed diagnoses and false negatives. Modern studies have shown that increasing the number of prostate puncture needles to 10–12 can improve the detection rate of prostate cancer without increasing the risk of complications. ¹⁷ , ¹⁸

This study compared the effectiveness of ultrasound‐guided transperineal puncture biopsy (TPBx) and TRBx using a 12‐needle puncture method in the diagnosis of prostate cancer. The results of the study showed that there was no statistical difference between the transperineal and transrectal groups in detecting prostate cancer, chronic prostatitis, and benign prostatic hyperplasia (p > .05). It suggests that both TPBx and TRBx methods are equally effective in diagnosing prostate cancer or other prostate cancers. It is worth noting that the detection rate of prostate cancer in the transperineal group was slightly higher than that in the transrectal group, which may be attributed to the better tissue samples obtained by transperineal puncture, which provides a more complete sample of the peripheral bands and apical part of the prostate gland, thus making it easier to detect early lesions and small lesions. ¹⁹ The latest study by Nalavenkata SB showed that transperineal puncture was significantly superior to transrectal puncture in detecting high‐grade anterior tumors. ²⁰ This also supports the notion that the transperineal approach provides a more complete sampling of the anterior part in this study. In terms of surgical index, the puncture time in the transperineal group was significantly longer than that in the transrectal group (p < .001), which may be due to the fact that transperineal puncture requires local infiltration anesthesia, and the puncture path is relatively long, making the procedure slightly more difficult. An important factor in assessing the safety of the puncture method is “puncture complications.” ²¹ There were no serious complications such as sepsis and prostate abscess in patients using both puncture methods. The results showed that complications such as urinary retention, bleeding, urethral distension, urinary tract infection, bloody stools, hematuria, dizziness, perineal distension, chest tightness, dyspareunia and fever were fewer in the transperineal group than in the transrectal group (p = .034), confirming its safety advantage. In addition, rectal mucosal injury during transrectal puncture may lead to infection and bleeding, whereas transperineal puncture circumvents the potential risk of the rectal route and reduces the probability of postoperative infection and bleeding. ²² A recently published systematic review clearly indicates that the transrectal route carries a significant risk of infection due to penetration of the rectal mucosa. In contrast, transperineal biopsy has consistently been reported to have an infection rate of less than 1% due to the avoidance of rectal flora. ²³ Although pain is not life‐threatening, severe pain can aggravate anxiety and even cause hypertension, increasing the risk of cardiovascular disease. ²⁴ In terms of pain scores, there was no significant clinical difference between the 2 groups in terms of VAS scores before puncture, but the VAS scores after puncture were significantly lower in the transperineal group than in the transrectal group (p < .001). This implies that postoperative pain control is better served by transperineal puncture. The fact that the puncture route was varied or the local anesthesia was effective may explain this difference. The transperineal puncture is more effective to reduce the pain caused by puncture by the local infiltration anesthesia while transrectal might cause post‐operative pain due to irritation of the rectal mucosa. In addition, the needle path of transperineal puncture is parallel to the long axis of the prostate, and the traveling path of the puncture needle is more in line with the anatomical structure, which reduces the damage to the surrounding tissues, and thus reduces the postoperative pain. ²⁵ One study found that the location of the core of the puncture was significantly associated with the degree of pain, where the core of the puncture located in the peripheral zone of the middle gland was associated with less severe pain. ²⁶ This laterally supports the idea that a puncture route that is more consistent with anatomical structures, such as the peripheral zone, may reduce pain. Negative emotions have a certain impact on human body functions and other symptoms. Prostate cancer patients, under the influence of surgical trauma and other factors, will experience some negative emotions, such as irritability, restlessness, anxiety, etc., which greatly affects the effectiveness of treatment. ²⁷ , ²⁸ The 2 scales used to assess patients' negative emotions were the HAMA and the HAMD. Before puncture, there was no statistically significant difference in HAMA and HAMD scores between the 2 groups of patients, however, following puncture, the HAMA and HAMD scores were significantly lower in the transperineal group than the transrectal group (p < .001). It implies that transperineal puncture is not only physiologically advantageous, but also better experienced at a psychological level for patients. It is possible that the incidence of postoperative complication and pain level is dependent on this difference. That helps to allay patients' anxiety and depression, reducing the pain they have immediately following the procedure, leading to a quicker psychological balance.

The novelty of this study lies in its comprehensive evaluation framework. While previous studies focused on cancer detection rates and complications, this study introduced a 5‐dimensional assessment system with pain scores and validated psychological scales (HAMA and HAMD) for the first time to quantify negative emotions in patients after biopsy. The findings suggest that transperineal biopsy not only reduced physical complications but also significantly alleviated anxiety and depression, providing a new perspective on patient‐centered prostate cancer diagnosis. Of note, the transperineal puncture group in this study was all completed in an outpatient setting using local infiltration anesthesia, which provides further evidence for the clinical feasibility and safety of transperineal puncture in the outpatient setting. However, in resource‐limited clinical settings, transrectal puncture may still be the more pragmatic option for now because of its ease of procedure and lower cost. Future research should focus on how to further simplify the procedure of transperineal puncture and optimize the local anesthesia regimen to make it a feasible diagnostic option in a wider range of clinical settings, so as to benefit more patients.

Limitations

Despite the strengths of this study, there are some limitations. The relatively small sample size of the study meant that our estimates of the overall parameters were not precise enough, thus reducing the validity of the test. Due to limited statistical power, the results we obtained from the study may not be reliable enough to generalize the findings to a wider group of patients. This was a single‐center study and the results may be limited by the clinical practice and skill level of a particular hospital. In addition, the study did not assess long‐term outcomes, such as the impact of biopsy method on subsequent treatment decisions and patient survival. Future studies should consider a multicenter, large sample size design and further explore the impact of different puncture methods on the long‐term prognosis of patients.

Conclusion

In conclusion, ultrasound‐guided transrectal prostate aspiration biopsy and transperineal prostate aspiration biopsy are both effective tests. However, transperineal puncture shows certain advantages in reducing postoperative complications, relieving pain and relieving negative emotions of patients, especially for patients with concerns about transrectal access or complicated with rectal diseases. Although the operation time is long and the technical requirements are high, in clinical application, doctors should comprehensively consider the specific conditions of patients and their own technical conditions to choose the most appropriate puncture method.

Data Availability Statement

The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.