Prostatic Fossa Pseudoaneurysm After Robot-Assisted Radical Prostatectomy (RARP): A Case Report

Introduction

Robotic radical prostatectomy is the preferred surgical treatment for patients with localized/locally advanced prostate cancer with a life expectancy of more than 10 years [1]. Hemorrhagic complications and hematuria in the perioperative period are rare [2], but they can be severe and prolong its morbidity. Prostatic fossa pseudoaneurysms have been described in the past with variable clinical presentations, most often with intermittent episodes of hematuria, with angioembolization being the preferred treatment modality [3]. Here, we describe a rare case of a pseudoaneurysm in the prostatic fossa as an early postoperative complication (<30 days) of RARP.

Case Report

A 58-year-old man with a history of type 2 diabetes mellitus, high blood pressure, dyslipidemia, and body mass index (BMI) of 23 kg/m2 was evaluated because of an increase in total prostatic specific antigen (PSA) to 4.52 ng/mL. He was taking metformin plus dapagliflozin, Olmesartan, and atorvastatin. Multiparametric magnetic resonance imaging revealed a PIRADS 4 lesion on the left peripheral zone and the prostate biopsy confirmed the diagnosis of prostate cancer, with 5 fragments out of 7 on the left positive for ISUP 2. The patient was offered RARP with extensive lymph node dissection for intermediate-risk prostate cancer after risk stratification of nodal involvement using the nomogram developed by Gandaglia et al. He underwent RARP by anterior transperitoneal approach with intrafascial dissection and bilateral preservation of the neurovascular bundles and puboprostatic ligaments. He was discharged from the hospital 1 day later without any complications, after checking creatinine in pelvic drainage and posterior removal of the pelvic drain. Two days later, he came to the Emergency Department (ED) with pain in lower abdomen quadrants and mild macroscopic hematuria that subsided after bladder irrigation. A blood study showed hemoglobin (Hb) 12 g/dL. Pelvic ultrasound imaging revealed anechogenic content in the prostate fossa that was difficult to characterize. The bladder catheter was removed on postoperative day 7. He subsequently returned to the ED 2 more times in the next 3 weeks with macroscopic hematuria and acute urinary retention (AUR), but blood and imaging studies did not reveal any alterations either time. Four weeks after surgery, he returned to the ED, with gross macroscopic hematuria with clots, requiring continuous bladder irrigation. His Hb was 9.6 g/dL. An angio-CT scan was performed (Figures 1–3), which showed hematoma/hematic content in the bladder lumen; at the site of the prostatectomy, a small amount of loculated fluid was observed, measuring approximately 45×18 mm; and within the collected fluid, an arterial pseudoaneurysm measuring approximately 22 mm was observed. He underwent percutaneous angiography through the right femoral access. An arterial pseudoaneurysm with tributary branches of the left internal iliac artery, left obturator artery, and left prostatic artery was diagnosed (Figure 4). Embolization of the pseudoaneurysm was performed with cyanoacrylate and 255–500-micron microparticles, with hematuria resolution. He was discharged 2 days later. Cystoscopy was not done during the investigation because the hematuria resolved after embolization and he did not have any risk factors for bladder cancer.

Discussion

Hemorrhage following radical prostatectomy is unusual, with an incidence of 0.5–1.6% [4,5]. Older series reported open drainage was the most successful treatment, avoiding long-term functional outcomes of hematoma persistence, such as bladder neck contracture and long-term incontinence [4,5]. Nowadays, endovascular management is used in most of these hemorrhagic complications because it is less invasive, but the management approach depends on the vessel involved and the hemodynamic status [3]. Postprostatectomy pseudoaneurysms (PPP) are a very rare complication, with the most recent series showing only 23 cases described in the literature [3]. They occur because of infections, trauma, malignancies, or iatrogenic causes, such as intraoperative arterial wall damage [6]. In our patient, arterial wall damage was the probable cause; it can result from small bleeding left behind in dissection when using a nerve-sparing approach. Another explanation may be in-block artery and veins ligature using clips or direct artery damage using mono-polar scissors [6,7]. As a result, the vascular anomaly is predis-posed to bleeding and the intermittent bleeding accumulated in the Retzius space drained through the vesicourethral anastomosis, leading to hematuria [7]. The artery most affected by this anomaly is the pudendal artery. In our patient, branches of this artery were also found to be involved in formation of the pseudoaneurysm. As a consequence, when embolization is performed there is a greater risk of erectile disfunction, since the pudendal arterial system provides the inflow for penile tumescence and rigidity [7]. Angiography can also have procedure-related complications, such as lesions at the punctured site, hematomas, arterial spasm, distal embolization, intimal dissection, and vessel thrombosis. The risk of developing complications is increased in interventional procedures, and the overall prevalence of severe vascular injuries is 0.02–9%. It also uses ionizing radiation and iodinated contrast material, which each have their own adverse effects [8]. In our patient, the bleeding started in the first week after surgery, and the pseudoaneurysm was diagnosed 4 weeks later. The reported cases in the literature show an 1–6 week period until the diagnosis is made [3]. The final diagnosis in our patient was made by CT scan and angiography, revealing the pseudoaneurysm formation, and these are the criterion standard in clinical management of this condition. The final treatment was percutaneous transcatheter embolization, which was the most frequently used treatment modality in previous reports, with good clinical outcomes.

Previous reports contain no mention of possible risk factors related to this complication. Our patient had diabetes, hyper-tension, and dyslipidemia. In a patient with uncontrolled hypertension in the postoperative period, small thermal injuries in these vessels can result in a larger lesion or even a vessel rupture, which can predispose to pseudoaneurysm formation. Diabetes and dyslipidemia can lead to chronic inflammation of the arterial wall and atherosclerotic plaques or even aneurysm formation. All these mechanisms of injury can contribute to hemorrhagic complications in the postoperative period in a fragilized vessel. This report highlights the importance of careful monitoring in managing bleeding after radical prostatectomy to achieve a correct diagnosis. A recent review on the management of hemorrhagic complications after minimally invasive radical prostatectomy (MIRP) revealed that 1/25 patients experience a clinically significant postoperative hemorrhage [2]. They can be divided in 3 management groups: surveillance without the need of transfusion, those who need transfusion, and those who require intervention. In that analysis, only 12/3749 men required intervention, 8 underwent exploratory laparotomy, 2 had laparoscopic exploration, and 1 had robotic exploration [2]. No bleeding was identified in 7 and sources of hemorrhaging were mainly from dorsal venous complex, pudendal artery, obturator artery, and the neurovascular bundle [2]. Only 25% of those who required an intervention had a CT angiogram previously [2]. The study attempted to grade the severity of hemorrhagic complications in the postoperative period, but the lack of adequate imaging studies in most of the patients who did an undergo an intervention could have led to a high proportion of major procedures. A better management algorithm for these patients may be upfront CT angiogram and urography followed by percutaneous embolization of identified bleeding sources, if possible, with major surgery as the last option.

Conclusions

Prostatic fossa pseudoaneurysm after RARP is rare. A high level of suspicion is required in patients with AUR and hematuria after surgery. Detection of a drop in hemoglobin should be followed by imaging studies such as CT angiography or percutaneous angiography to make a correct diagnosis and exclude possible life-threatening complications. Treatment using percutaneous embolization can be effective, with good outcomes.