Robotic Management of Pelvic Lipomatosis-Experience with Difficulties Encountered and the Techniques to Successful Outcomes

Pelvic lipomatosis-a rare diagnosis and a challenging management: a case report and literature review

Pelvic lipomatosis (PL) involves nonmalignant excess fat growth in perirectal and perivesical areas, gaining recognition over three decades. This review addresses its clinicopathological aspects amid controversies, emphasizing the need for a comprehensive examination of current literature. This report outlines a 42-year-old man's diagnostic journey for persistent urological symptoms, ultimately identified as PL. PL, if untreated, adversely impacts the urinary system, affecting kidney function and causing systemic complications. Management involves accurate diagnosis through radiological methods and surgical intervention, aiming to alleviate symptoms and enhance affected individuals' quality of life.

Modified Ileal Conduit for Pelvic Lipomatosis: Technique Description and Outcome

INTRODUCTION

The aim of this study was to present the surgical technique and clinical outcomes of modified ileal conduit for pelvic lipomatosis (PL).

METHODS

From 2020 to 2022, we prospectively enrolled 9 patients with PL undergoing modified ileal conduit. The patient characteristics, perioperative variables, and follow-up outcomes as well as the description of surgical technique were reported.

RESULTS

All 9 patients successfully completed the operation. Two patients had perioperative complications of Clavien-Dindo grade I. The mean operation time and bleeding volumes were 253 ± 51.4 min and 238.9 ± 196.9 mL, with a mean postoperative follow-up time of 13.0 ± 5.6 months. The postoperative 3-month and 1-year creatinine values were significantly decreased versus the preoperative (p = 0.006 and p = 0.024). The postoperative 3-month and 1-year estimated glomerular filtration rate values were significantly increased compared with those before operation (p = 0.0002 and p = 0.018). The separation value of left renal pelvis collection system after operation was significantly reduced compared with preoperative evaluation (p = 0.023 at 3 months and p = 0.042 at 1 year) and so was the right side (p = 0.019 and p = 0.023).

CONCLUSION

Modified ileal conduit is safe and feasible for PL. A large sample cohort with long-term follow-up is needed to evaluate the clinical outcomes of PL.

Ureteral reimplantation for the management of pelvic lipomatosis

Introduction

Pelvic lipomatosis is a rare benign disease characterized by urethral elongation, bladder deformity, and/or hydronephrosis. Conservative management is not effective, and urinary diversion is the most effective treatment option but is usually unacceptable for relatively young patients. Ureteral reimplantation seemed to be an appropriate modality under these conditions. We present one case in which pelvic lipomatosis was managed with ureteral reimplantation.

Patient presentation

A 45-year-old, previously healthy man presented with right flank pain. Pelvic CT and CT urography showed excessive pelvic fat, bilateral hydronephrosis, tortuous ureters, and a pear-shaped bladder, all of which indicated a diagnosis of pelvic lipomatosis. We performed laparoscopic bilateral urinary tract infection on this patient. At follow-up, bilateral hydronephrosis and flank pain were greatly relieved.

Conclusion

Pelvic lipomatosis can be managed safely and effectively by urinary tract infection, but longer follow-up periods are needed to evaluate the long-term efficacy of this approach.

Exploring a simplified way to diagnose pelvic lipomatosis: prediction of pelvic fat volume using a single cross-sectional image

Background

Pelvic lipomatosis (PL) is a rare disease characterized by the overgrowth of pelvic adipose tissue (AT). We investigated the relationships between areas of subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) and pelvic fat volume (PFV), and analyzed the feasibility of diagnosing PL from a single cross-sectional image.

Methods

The study included 50 patients and 50 controls. We used nnU-Net to segment SAT and VAT automatically. L3 vertebra was set as the zero point (L0), and a total of 201 slices were obtained with a 1 mm interval (L-100 - L+100). We selected 5 pelvic slices, including slices of the anterior superior margin of the S1-S4 vertebrae and the slice above the bilateral femoral head (FH). SAT areas, VAT areas, and PFVs were calculated by computational software. Areas and volumes of 2 groups were compared by t-test or rank-sum test. The correlations among areas and PFV were calculated. Logistic regression models were developed to identify the best slice for predicting PL. Receiver operating characteristic (ROC) curves were performed, and the area under the curve (AUC) and thresholds [with sensitivity (SEN) and specificity (SPE)] were calculated.

Results

VAT areas of L-94 - L-100, L+79 - L+100, S1-S4, and FH indicated statistical differences between patients and controls (P<0.05). The linear regression model with VAT area as the independent variable was established to estimate PFV (FH level: r=0.745, P<0.001, R2=0.555). Among the univariate logistic regression models, VAT area at FH as the independent variable had the highest performance in predicting PL (AUC: 0.893, SEN: 74%, SPE: 94%), followed by S4 level (AUC: 0.800, SEN: 88%, SPE: 66%). The overall accuracy of the logistic regression model including VAT areas at S4 and FH in predicting PL was 88% (AUC: 0.927, SEN: 90%, SPE: 88%).

Conclusions

VAT areas at the level of FH can help estimate the value of PFV. VAT areas of S4 and FH provide greater power than a single image for the diagnosis of PL.

Surgical treatment of pelvic lipomatosis: a systematic review of 231 cases

Background

Pelvic lipomatosis (PL) is a rare condition that is characterized by excessive growth of fat in the pelvic cavity. Studies have yet to systematically review surgical treatments for PL.

Objectives

To provide a reference for selecting reasonable surgical treatments for PL patients according to previous literature on the surgical treatment of PL.

Design and methods

We conducted this systematic review in accordance with the Preferred Reporting Items for a Systematic Review and Meta-Analysis (PRISMA) of Individual Participant Data guidelines. Literature on PL published from 1968 to 2022 was retrieved from the PubMed and EMBASE databases. Data were collected and analyzed independently by two independent investigators.

Results

A total of 42 studies, involving 231 patients with PL, were included in the analysis. The surgical treatments included transurethral resection (TUR) (48.5%), ureteral stent placement (11.7%), percutaneous nephrostomy (1.3%), ureterocutaneostomy (1.3%), ureteral reimplantation (10.4%), ileal conduit (13%), and allograft kidney transplantation (0.4%). After excluding patients with unclear prognoses, 42.9% of patients showed improvement in lower urinary tract symptoms (LUTS) after TUR. Ureteral stent placement provided relief of hydronephrosis in 62.5% of PL patients. Percutaneous nephrostomy resulted in stable renal function in 33.3% of PL patients, while ureterocutaneostomy led to remission of postoperative hydronephrosis in 33.3% of PL patients. After ureteral reimplantation, 70.8% of patients experienced relief of hydronephrosis or had stable renal function. Ileal conduit led to remission of hydronephrosis, alleviation of symptoms, or maintenance of stable renal function in 83.3% of PL patients. One patient with PL had stable renal function after allograft renal transplantation.

Conclusion

The surgical treatments for PL include TUR, ureteral stent placement, urinary diversion, and allograft renal transplantation. However, the choice of surgical method should be determined after comprehensive consideration of the patient's condition.

Robotic Local Fat Extirpation and Ureteric Reimplantation for Pelvic Lipomatosis with Ureteric Obstruction: Technical Considerations

Background:

Ureteric reimplantation is the treatment of choice for pelvic lipomatosis with ureteric obstruction. Pelvic adherent fat poses a technical challenge during this surgery.

Description of Technique:

We describe the robotic approach to facilitate the precise dissection of the ureter and bladder in adherent fat. After creating pneumoperitoneum and port placement, the ureter is exposed at the iliac crossing and dissected distally. Perivesical fat at the intended site of ureteric reimplantation is excised and cystotomy is done. Ureterovesical anastomosis is performed over a stent.

Patients and Methods:

Two patients with pelvic lipomatosis causing ureteric obstruction and renal function impairment underwent robotic ureteric reimplantation at our institute. Technical aspects and outcomes are discussed here.

Results:

Blood loss was minimal. No intra-operative or post-operative complication was noted. Renal function improved for both patients.

Conclusion:

Robotic approach helps to overcome the technical difficulties posed by adherent fat during ureteric reimplantation in pelvic lipomatosis.

Pelvic lipomatosis associated with bilateral obstructive uropathy and proliferative cystitis

Pelvic lipomatosis is a rare benign entity characterised by excessive deposition of adipose tissue in the perirectal and perivesical spaces. We describe a 43-year-old man with bilateral distal ureteral obstruction secondary to pelvic lipomatosis with concomitant proliferative cystitis resulting in severe hydronephrosis. We performed urinary diversion with percutaneous nephrostomy tube insertion to prevent further renal impairment. The patient was advised close follow-up to monitor the increased risk of bladder adenocarcinoma transformation observed in patients with cystitis glandularis. This report, compliant with the CARE (CAse REport) guidelines for clinical case reporting, presents another case of pelvic lipomatosis associated with acute kidney failure, bilateral hydronephrosis and proliferative cystitis without urodynamic evidence of bladder outlet obstruction that may serve to guide urologists in managing patients with a similar profile.