BLDE University Journal of Health Sciences

REVIEW ARTICLE
Year
: 2021  |  Volume : 6  |  Issue : 1  |  Page : 22--30

Role of ureterolysis in the management of retroperitoneal fibrosis: A systematic review


Rami Boulma1, Akil Mestiri2, Hassen Khouni1, Bilel Saidani1, Adnen Chouchen1,  
1 Department of Surgery, Interior Security Forces Hospital, La Marsa, Tunisia
2 Daytime Hospital Department, Interior Security Forces Hospital, La Marsa, Tunisia

Correspondence Address:
Dr. Rami Boulma
Department of Surgery, Interior Security Forces Hospital, La Marsa
Tunisia

Abstract

The purpose of the present study is to assess the outcome of ureterolysis in the management of ureteral entrapment secondary to retroperitoneal fibrosis (RPF). A literature search of online database PubMed for studies about ureterolysis was performed. The keywords used for this literature review were: “Retroperitoneal fibrosis” and “Ureterolysis.” Articles in English published between 1980 and 2019 were included. Articles published in non-English language, without full text or lacking of relevant data, were excluded. Clinical perioperative and outcome data were collected, analyzed, and compared between open, laparoscopic, and robotic ureterolysis subgroups. Postoperative complications were recorded according to the Clavien classification. One hundred and six articles were initially collected. After analysis, 37 articles were finally selected for the review. The number of patients was 402. The number of renal units was 554. The median age of our population was 54.55 years (36.5–71). The male/female ratio was 1.71. RPF was idiopathic in 312 patients (77.61%). Ureterolysis was bilateral in 131 cases. The mean success rate in open ureterolysis was 90.45% (77%–100%), the mean success rate in laparoscopic ureterolysis was 93.72% (77.8%–100%), and the success rate in robot-assisted ureterolysis was 100%. Most complications were Clavien I and II. Clavien V was noted in four patients. Ureterolysis is an effective treatment in the management of ureteral entrapment in RPF. It is a safe procedure with possible but manageable complications. It can be proposed in cases of medical therapy failure.



How to cite this article:
Boulma R, Mestiri A, Khouni H, Saidani B, Chouchen A. Role of ureterolysis in the management of retroperitoneal fibrosis: A systematic review.BLDE Univ J Health Sci 2021;6:22-30


How to cite this URL:
Boulma R, Mestiri A, Khouni H, Saidani B, Chouchen A. Role of ureterolysis in the management of retroperitoneal fibrosis: A systematic review. BLDE Univ J Health Sci [serial online] 2021 [cited 2021 Dec 9 ];6:22-30
Available from: https://www.bldeujournalhs.in/text.asp?2021/6/1/22/313358


Full Text



Although retroperitoneal fibrosis (RPF) was firstly described in 1905, there is still no clear consensus about the exact management of this disease. RPF is a quite mysterious disease characterized by the formation of fibrosis plaque mainly around retroperitoneal vascular structures.

In 70% of cases, no evident etiology is found and the RPF is called idiopathic. The remaining cases are caused by inflammatory diseases, malignancies, and some long-term medications.[1]

The major complication of this fibrosis plaque is ureteral entrapment, and consequently renal obstruction. Ureteral involvement is seen in up to 80%–100% of RPF.

Multiple treatments have been tried in order to release the ureter from the fibrosis. Therefore, medical treatment, ureteral endoscopic stenting, and surgical ureterolysis have been performed for this purpose. Ureterolysis is thought to be a quite morbid procedure with significant risk of ureteral injury.

The success of endourology these late decades encourages many authors[2],[3] to manage ureteral entrapment with ureteral stenting and corticosteroid therapy. This association is considered to be conservative, low morbid, and effective. However, the long-term morbidity, efficacy, and cost of this conservative option are questionable.

As an alternative to conservative management of ureteral entrapment in RPF, we have tried to assess the outcome of ureterolysis in this pathology. Our assessment was performed through a literature review about ureterolysis in RPF.

Finally, we will try to give more clarity about the management of this pathology.

A literature search of online database PubMed for studies dealing with ureterolysis was performed. The keyword used for this literature review were: “Retroperitoneal fibrosis” and “Ureterolysis.”

Articles in English published between 1980 and 2019 were included. Surveys including data from different centers have not been included.

Articles published in non-English language, without full text or lacking of relevant data, were excluded. Clinical perioperative and outcome data were collected, analyzed, and compared between open, laparoscopic, and robotic ureterolysis subgroups.

Different indications of ureterolysis have been reported in literature.

Usually, patients suffering from idiopathic RPF get corticosteroid therapy as a primary line treatment. If corticosteroid therapy is not able to release the ureter from fibrosis plaque, patients are considered in medical therapy failure and thus require ureterolysis. Ureterolysis is also indicated in patients in whom ureteral stent is impossible, or in case of bothering stent-related symptoms. Ureterolysis could be also proposed as a primary treatment if ureteral obstruction is thought to be unlikely resolved by medical therapy alone.

The success of ureterolysis is defined by the absence of evidence of obstruction or need for a second procedure at the last follow-up visit. Postoperative complications have been recorded according to Clavien classification. Data have been analyzed with Microsoft Excel 2013.

One hundred and six articles have been initially collected through PubMed online research using the keyword: “retroperitoneal fibrosis” and “ureterolysis.” After analysis, 37 articles were finally selected for the review. The reasons of the exclusion of the remaining articles were non-English articles, absence of full texts, lack of relevant data, no ureterolysis performed, absence of follow-up, and case reports dealing with extreme rare entity.

A multi-institutional survey about laparoscopic ureterolysis was not included because of redundant data with other selected articles.

The selected articles have been published from 1980 to 2019. All were retrospective studies, except one prospective study. The detailed data of the different series are given in [Table 1].[4],[5],[6],[7],[8],[9],[10],[11],[12],[13],[14],[15],[16],[17],[18],[19],[20],[21],[22],[23],[24],[25],[26],[27],[28],[29],[30],[31],[32],[33],[34],[35],[36],[37],[38],[39],[40]{Table 1}

The number of patients was 402. The number of renal units was 554. The median age of our population was 54.55 years (36.5–71). The male/female ratio was 1.71.

The median body mass index was 27.66 (25–32.6) kg/m2.

RPF was idiopathic in 312 patients (77.61%). Ureterolysis was bilateral in 131 cases.

The indication of ureterolysis was variable in-between authors, including primary ureterolysis in 218 patients (54%), medical therapy failure in 110 patients (28%), stent failure in 40 patients (10%), stent symptoms in 22 patients (5%), abdominal aorta aneurysm surgery in 8 patients (2%), and patient desire in four patients (1%).

The delay between the diagnosis of RPF and ureterolysis was not always mentioned and varies considerably from series. It ranged from 2 weeks to 1 year, depending on whether the patient has been treated medically or not.

A preoperative ureteral stenting was performed when possible in the majority of cases in order to facilitate the identification of the ureter.

Open ureterolysis (OU) was performed for 370 renal units, laparoscopic ureterolysis (LU) was done for 142 renal units, and robot-assisted ureterolysis (RU) was realized for 34 renal units. In the group of laparoscopic ureterolysis, a hand-assisted technique was used in 13 renal units to facilitate ureteral identification with tactile sensation.

Nephrectomy for severe plaque extension and poor/non-functioning kidney was done for eight renal units. All the patients underwent retroperitoneal biopsy in order to look for the etiology of the disease.

Additional surgical procedures were realized in order to reduce the likelihood of recurrence of ureteral fibrosis entrapment, including omental wrapping in 231 renal units and ureter intraperitonization in 105 renal units. Ileal conduit diversion for severe bilateral ureter entrapment and impossibility of ureter liberation was performed in two patients.

For severe distal ureteral entrapment, a Boari flap, ureteral ileal replacement, and ureteral reimplantation were done in three, two, and three renal units, respectively.

Ureteral injury was the most frequent preoperative complication of the ureterolysis occurring in nine renal units; the management was successful after simple suture and ureter stenting.

The median operative time (minutes); estimated blood loss in milliliter; hospital stay duration (days); and success rate for open, laparoscopic, and RU are summarized in [Table 2]. Conversion to OU was done in laparoscopic ureterolysis group because of operative difficulty in ten renal units. No conversions were noted in the RU group.{Table 2}

The postoperative ureteral stenting was realized with a double J stent with a median duration of 4.25 weeks (1–12).

Among our population, four deaths have been noted: two secondary to a congestive heart failure 2 weeks following a laparoscopic ureterolysis, one secondary to acute renal failure, and one due to recurrence of a malignant retroperitoneal tumor.

The postoperative complications according to Clavien classification are reported in [Table 3].{Table 3}

The most serious complications that have been noted in the open ureterolysis group were as follows: prolonged ileus in four patients, wound discharge in three cases, urinary tract infections in three cases, deep-venous thrombosis in three cases, two due to pneumonia, one due to pulmonary embolism, two due to prolonged urine leakage, one due to glomerulonephritis, and one due to wound cellulites.

The most reported complications in laparoscopic ureterolysis were as follows: one intraoperative injury of iliac vein, three prolonged ileus, two deep-venous thrombosis, one urinary retention, one epididymitis, one port-site infection, one urinary tract infection, and one fascial dehiscence.

Complications in RU were as follows: one enterocutaneous fistula, following difficult ureter dissection due to an extensive fibrosis plaque.

The median follow-up was 23.84 months (3–84).

The mean success rate in open ureterolysis was 90.45% (77%–100%), the mean success rate in laparoscopic ureterolysis was 93.72% (77.8%–100%), and the success rate in RU was 100%.

RPF is defined as a retroperitoneal fibroblastic proliferation associated with a chronic inflammation developing around retroperitoneal vascular structures. Ureteral obstruction occurs in most of cases, representing the main issue of the disease.[41]

Most cases of RPF are idiopathic; secondary cases can be due to infections, retroperitoneal surgery, some drugs, or malignancies.[41] The first step for the management is to rule out and treat malignancies causing RPF. The main goal of the management of RPF is to relief renal obstruction through the release of ureter from RPF.

Ureteral obstruction secondary to RPF can be managed either by renal stenting followed by medical therapy or by a primary surgical ureterolysis.[5] Medical therapy may include corticosteroid, immunosuppressive agents, and/or cytotoxic agents.

The exact role of ureterolysis in the management of RPF is still not well defined. There is no consensus in the literature as whether it should be proposed as primary line treatment or rather in case of conservative management failure. This confusion toward the manner to deal with this pathology is due to the poor understanding of the disease. Indeed, the available data concerning RPF come from case reports, small series, and retrospective studies with low proof level.[17]

Ureterolysis is performed since 1934 for the management of ureteral obstruction in RPF. This procedure is thought to be associated with high morbidity and even mortality rate. Furthermore, the progress of endourology in the last decades, encourages a lot of authors.[2],[3] To propose a long-term ureteral stenting associated with medical therapy mostly corticosteroid therapy for the management of RPF. However, a lot of questions remain without definitive answer regarding this conservative management. Can ureteral stenting achieve a complete relief of ureteral obstruction caused by an extrinsic ureteral entrapment? Is this conservative management a long-term efficient attitude? What about the morbidity, the cost of a long-term ureteral stenting?

Docimo and Dewolf[42] in a comparative study between intrinsic and extrinsic ureteral obstruction, showed that relief of obstruction failed in about 50% of cases of extrinsic obstruction after ureteral stenting. They concluded that ureteral stenting is much more effective in ureteral desobstruction secondary to an intrinsic obstruction such as stone or endoluminal stenosis rather than extrinsic obstruction.

The same authors estimated the annual cost of polymer ureteral stenting, when considering four stent exchanges/year, costing about 9648 dollars.

Up to 70% of patients with chronic ureteral stenting report pain requiring medications. Other stent-related symptoms include urgency, frequency, and dysuria, which have been frequently reported.[43]

Additionally, these authors insist about the loss of productivity and absenteeism caused by the iterative ureteral exchange, which has been evaluated as 6 days per procedure.

Corticosteroids are quite effective during the inflammatory phase of the disease when the fibrous plaque is particularly vascularized.[5] However, with time, fibrosis plaque becomes less vascularized and the effectiveness of corticosteroid becomes low. Hence, the idea of getting good result after long-term corticosteroid and stenting has weak arguments. In the conservative management of RPF, there is no consensus about the type, duration of the medical drugs, and the duration of ureteral stenting. This lack of homogeneity between the series does not facilitate comparison.

The association of ureteral stenting and corticosteroid in the management of obstruction in RPF showed a success rate between 75% and 86%.[2],[3] However, criteria of success in the literature are heterogeneous, stent-related symptoms are not always taken into consideration, and the average stent duration was about 19 months, with an extreme of 60 months. Could we speak about success in a patient still stented 60 months after onset of the disease? Long-term corticosteroid therapy complications have to be also considered especially in some at-risk patients.

Ureterolysis was successful in >90% of cases in our literature review. Ureteral desobstruction seemed to be stable in time at a median follow-up of 23.8 months. Among the 402 operated patients, we have noted only four deaths, but these deaths were rather due to patients' comorbidities and not specific to the surgery. The most frequent preoperative complication was ureteral injury noticed in nine renal units. Ureteral injury was efficiently repaired with suturing and stenting of the ureter. Postoperative complications were mostly classified Clavien I and II, so quite manageable.

Our results clearly demonstrate that ureterolysis is an efficient procedure with manageable complications in most of the patients.

The reported failure in ureterolysis cases is mostly due to a subsequent ureteral entrapment by the fibroses, or because of the important delay of ureterolysis when considering medical therapy first.[23]

Interestingly, high-volume centers have showed much better results in terms of ureteral release and acceptable rate complications. Indeed, O'Brien and Fernando[17] in a prospective study about ureterolysis in RPF reported a success rate of 96%. The criteria for postoperative success were even though strict: symptom free, stent free, and drug free. Clavien III and IV complications were noted in 12% of patients, with success management without significant functional impact. These authors suggest ureterolysis in all patients that are not stent free within 6 months of medical treatment. They added that ureterolysis should rather be done at a high-volume center, because it is a technically demanding procedure, with a possibility of additional procedures.

Furthermore, ureterolysis allows deep plaque biopsy offering a qualitative sampling, which contributes to an accurate etiologic study. Surprisingly, Mufarrij et al.[15] reported pain relief in patients undergoing ureterolysis even in the absence of preoperative hydronephrosis. These authors assume that this relief is due to the splitting of fibrous capsule of RPF, resulting in lowering pressure on the retroperitoneal nerves.

The precise timing and indication for ureterolysis is not consensual. In our literature review, the main indications were primary ureterolysis in 218 patients (54%), medical therapy failure in 110 patients (28%), and stent failure in 40 patients (10%). In a multi-institutional survey assessing laparoscopic ureterolysis, the first indication of surgery was medical therapy failure in 88% of cases.[44] The decision to switch for surgery may vary a lot from different authors according to patient's features, extent of fibrous plaque, and the surgical skills of the urologists. Primary ureterolysis is performed when the extent of fibrosis plaque and the degree of hydronephrosis are thought to be untreatable by medical therapy. However, this remains a quite subjective evaluation and most of the authors do not precise the plaque's dimension and/or degree of obstruction.

The most reasonable attitude would be to start with corticosteroid therapy associated with ureteral stenting for 6 months and perform salvage ureterolysis in case of medical therapy failure. This attitude is chosen by a multitude of authors with vast experience in the management of RPF.[14],[17],[44] The other indications of ureterolysis are more consensual including stent failure, stent-related symptoms, malignant RPF, and patient's choice for surgery.

In association with ureterolysis, additional surgical procedures were realized in order to reduce the likelihood of recurrence of ureteral fibrosis entrapment. According to our review, these procedures included omental wrapping in 231 renal units and ureter intraperitonization in 105 renal units.

Omental wrap is thought to act as a barrier preventing ureteral entrapment by fibrosis plaque and giving a vascular supply to the traumatized ureter.[17] Indeed omental cells have the ability to synthetize angiogenic factors such as fibroblast and vascular endothelial growth factor.[45]

If omental wrap is technically impossible, peri-colonic fat is interposed between the colon and ureter, realizing ureteral intraperitonization. The goal is the same as in omental wrapping: exclusion of the ureter from the RPF plaque.[5] However, the exact contribution of omental wrapping in the success of ureteral is still not well established. Thus, there are no comparative randomized controlled studies comparing ureterolysis with and without ureterolysis.

Bilateral ureteral involvement in RPF is reported in 67% of cases. This involvement is not necessarily synchronous, but may occur later during the follow-up.[22]

Because of this high rate of bilateral ureteral involvement, some authors perform prophylactic ureterolysis of an uninvolved contralateral ureter. They argue that RPF is a potentially evolutive disease with a high risk of bilateral ureteral entrapment. Contralateral ureterolysis performed during a second procedure would be technically more difficult especially when it is an open surgery. This attitude of treating both ureters simultaneously is nowadays obsolete because of the concern about a “preventive” surgery. Many contemporary authors[10],[14],[15],[23] performing laparoscopic ureterolysis did not perform prophylactic ureterolysis. Thus, they did not report disease development of contralateral side and think that contralateral ureterolysis if needed could be performed without increased morbidity through laparoscopy.[14],[15]

Adjuvant corticosteroids are prescribed by some authors[35] in order to reduce the probability of ureteral re-entrapment. Furthermore, corticosteroids aimed to treat the systemic manifestations of RPF could not be ruled out by surgery. Postureterolysis, corticosteroid therapy had been used rarely in our review (twenty cases) when laboratory tests or imaging presumed a recurrence of the disease. No evident benefits of adjuvant corticosteroid therapy has been reported by Duchene et al.[44]

Ureterolysis can be performed according to the expertise of the surgeon via an open approach, laparoscopic, which could be hand assisted one, or robotic ureterolysis (RU).

Laparoscopic ureterolysis was initially performed in the 1990s. It was successful but required long operative time and occasional significant complications.[6],[32] Current data[44] showed much lower morbidity, no mortality, and a success rate exceeding 90%. This outcome pushed some authors to propose laparoscopic ureterolysis as a first-line consideration in the management of RPF.[9],[32] The main issue with laparoscopic ureterolysis, when comparing to open surgery, is the absence of tactile perception. This may be problematic in identifying the ureter and performing its liberation, in particular severe disease. This encouraged some authors[6] to perform hand-assisted laparoscopy. These authors proposed to initiate the procedure with standard laparoscopy, in case of difficulty to convert not to open but rather to hand-assisted laparoscopy. Duchene et al.[44] reported the results of a multi-institutional survey about laparoscopic ureterolysis, with an overall success rate of about 83%. There were no statistically significant differences between the three groups: laparoscopic, hand-assisted laparoscopy, and robot-assisted laparosopic ureterolysis. The same authors could not draw any conclusions about the exact usefulness of omental wrap because of the small number of patients.

The results of our review showed better success rate of robotic ureterolysis (100%) over conventional laparoscopic ureterolysis (93.72%) and open ureterolysis (90.45%). However, the comparison is comparatively imprecise because of the possible heterogeneity of the groups.

Elashry et al.[38] compared the results of laparoscopic (six patients) versus open (seven patients) ureterolysis. They found a similar success rate but lower morbidity, hospital stay, and analgesics consumption in laparoscopic group patients.

Robotic ureterolysis is a very effective procedure with a success rate reaching 100%. Keehn et al.[14] reported the results of 17 patients (21 renal units) undergoing RU. These authors report that the use of robotics offers greater visual perspective and dexterity. These advantages explain the relative low morbidity of this kind of surgery: only one case of enterocutaneous fistula in this series. Robot-assisted surgery facilitates deep tissue biopsy, which is important for the accurate histologic diagnosis of RPF. Much more advantages of robotic surgery are reported by the authors performing this technique (e.g., wide possibilities of wrist movement, sharp movement, tremor elimination, stable magnified three-dimensional view, and surgeon comfort).[15] The extraordinary movement possibilities of the articulated arm allow a complete circumferentially ureteral liberation from the fibrosis plaque. It might be one of the reasons of the excellent results of RU.[15],[26]

 Conclusion



Ureterolysis is an effective tool for the management of ureteral entrapment in RPF. It is a quite safe procedure especially in skilled surgeons with possible manageable complications. Ureterolysis is the only effective procedure in relieving obstruction in case of medical therapy failure.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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