Solid Primary Retroperitoneal Masses in Adults: An Imaging Approach

Traumatic retroperitoneal neuroma at the site of prior radical nephrectomy: A case report

We present a case of a 68-year-old male with past history of renal cell carcinoma and radical nephrectomy, who developed a traumatic retroperitoneal neuroma at the site of his prior surgery thirteen years later which initially was thought to be a cancer recurrence. We review the patient's past medical history, clinical presentation, and disease course. Finally, we provide a brief review of retroperitoneal peripheral nerve lesions and discuss current approaches to their management.

The value of contrast-enhanced ultrasound in percutaneous biopsy of retroperitoneal masses

PURPOSE

To evaluate the diagnostic yield of contrast-enhanced ultrasound (CEUS)-guided biopsy of retroperitoneal masses (RMs).

MATERIALS AND METHODS

Between 2006 and 2023, 87 patients presented at our US center for biopsy of an RM. In all biopsies, CEUS was performed prior to the intervention. The technical success rate of biopsy, the presence of diagnostic tissue in solid tumor biopsy samples, the accuracy of the biopsy and the occurrence of post-interventional complications were evaluated.

RESULTS

A US-guided biopsy could be conducted in 84/87 cases (96.6%). In 3/87 cases (3.4%), US-guided biopsy was impossible because the planned needle path was obstructed by vital structures. Of 84 lesions, 80 (95.2%) were solid lesions, and 4 (4.8%) were lesions containing fluid. In all solid tumors, 80/80 (100%), diagnostic vital tissue was successfully obtained. CEUS-guided biopsy showed a sensitivity of 93.2%, a specificity of 100%, a positive predictive value of 100%, a negative predictive value of 72.2%, and a diagnostic accuracy of 94.2% for the differentiation between malignant and benign RMs. In one of the 84 cases (1.2%), there was a complication of postinterventional abdominal pain.

CONCLUSION

Percutaneous CEUS-guided biopsy is a safe procedure with a high diagnostic yield and a low complication rate.

Salmonella bovismorbificans abscess masking a primary testicular tumour in the retroperitoneum - A case report

INTRODUCTION AND IMPORTANCE

Testicular tumours can present outside the testis in about 5 % of cases, including as a primary lesion within the retroperitoneal space. These arise insidiously and can be hard to detect. Salmonella is an uncommon cause of abscess formation and the subtype of bovismorbificans, arising from geckos, only scarcely reported to cause an abscess. We describe a case in line with SCARE Criteria where a retroperitoneal non-seminomatous germ cell tumour presented with a salmonella bovismorbificans abscess and subsequent bacteraemia.

CASE PRESENTATION

A 37 year old male presented unwell with fevers and right flank pain suggestive of pyelonephritis. He had a salmonella bacteraemia on initial blood cultures, subsequently isolated to be salmonella bovismorbificans, and a CT scan demonstrate a large 7.7 cm retroperitoneal mass with surrounding lymphadenopathy.

CLINICAL DISCUSSION

An initial attempt at tissue sampling failed as the lesion was filled with purulent material requiring a pig tail drain to remain in place. He progressed slowly with resolution of fevers and bacteraemia however the lesion did not reduce in size despite adequate antibiotic treatment for two weeks. A repeat core biopsy and aspiration after 19 days revealed ongoing salmonella infection with a yolk sac tumour and seminoma. His AFP markers at this time were elevated at 3330kIU/L.

CONCLUSION

A underlying malignancy should be consider when a retroperitoneal abscess fails to resolve with adequate treatment especially when a organism unknown to cause abscess is isolated.

Comprehensive neurosurgical and visceral surgical therapy of retroperitoneal nerve tumors: a descriptive and retrospective analysis

Nerve tumors in the retroperitoneal space are a rarity. Radical surgery according to soft tissue tumors can lead to persistent pain and neurological deficits. This study aims to evaluate clinical outcomes of patients treated by a visceral- / neurosurgical approach. 33 patients with a retroperitoneal nerve tumor underwent surgery between 01/2002 and 12/2022 at our department. A visceral surgeon provided access to the retroperitoneal space, followed by micro-neurosurgical tumor preparation under neuromonitoring. Clinical examination and MRI were performed 12 weeks after surgery and further 3 months (WHO grade > 1) or 12 months (WHO grade 1). Further examinations were based on MRI findings and residual symptoms with median follow-up time of 24 months. One patient was treated for two distinct masses resulting in a total of 34 histological findings. Schwannomas (n = 15; 44.1%) and neurofibromas (n = 10; 29.4%) were the most common tumors. Long-term improvements were noted in radicular pain (15/18 patients; 83.3%), motor deficits (7/16 patients; 43.8%), abdominal discomfort and pain (5/7 patients; 71.4%). Recurrences were observed in 3/33 (9,1%) patients. This study represents the largest series of retroperitoneal BPNSTs treated with microsurgical techniques. Prospective multicenter studies are warranted to establish standardized treatment guidelines.

The value of contrast-enhanced ultrasound in differentiating benign from malignant retroperitoneal masses

OBJECTIVES

To evaluate the value of contrast-enhanced ultrasound (CEUS) perfusion patterns in the differentiation of benign and malignant retroperitoneal masses (RMs).

METHODS

Between 2006 and 2023, 122 consecutive patients with an RM visualizable by B-mode US were investigated additionally with CEUS. On CEUS, the extent of enhancement (classified as marked, reduced, or absent) and the homogeneity of enhancement (HE; classified as homogeneous or inhomogeneous) were evaluated. Subsequently, the malignancy rate according to CEUS perfusion patterns was determined.

RESULTS

On CEUS, marked enhancement was significantly more frequently associated with malignancy than with benignity (p < 0.0001, Fisher's exact test). All lesions with no enhancement were benign. Regarding HE, there was no significant difference between benign and malignant lesions (p = 0.07, Fisher's exact test).

CONCLUSION

On CEUS, marked enhancement in an RM may be indicative of a malignant lesion. Furthermore, absent enhancement can be considered to be an indication of benignity. The use of CEUS can be helpful in the evaluation of the malignancy of retroperitoneal masses.

A road to surgical success: a case report of huge retroperitoneal idiopathic non-pancreatic cyst in a 6-year-old child at tertiary hospital, Muhimbili National Hospital

In most reported cases, pancreatic pseudocysts are the most commonly reported cases and mostly occur in adults. Idiopathic non-pancreatic pseudocyst is rarely reported among children. We are reporting a rare case of retroperitoneal pseudocyst in a 6-year-old male with a 4-week history of abdominal swelling. He had asymmetrical abdominal distention on the right lumber and iliac regions with a smooth surface measuring 12 × 22 cm in its largest dimension. CT scan showed a mesenteric cyst, ipsilateral hydronephrosis, and intrahepatic duct dilatations. Intraoperatively, a retroperitoneal cystic mass was completely excised histologically confirmed pseudocyst. The patient was discharged home after fully recovery after 4 days of surgery. Surgical interventions remain to be the stay management of retroperitoneal pseudocysts with an earlier full recovery. Open surgical technique remains to be a preferred approach, especially for the large and complex retroperitoneal cysts.

Renal cell carcinoma metastasis without a primary: A case report

In Australia, approximately 3 % of all cancers diagnosed each year are renal cancers. Renal Cell Carcinoma (RCC) represents 90 % of all primary renal malignancies. RCC are slow growing and often asymptomatic, thus are often found incidentally. Here we present the case of a 76-year-old male who was found to have a metastatic RCC in a para-aortic lymph node with no primary lesion. He underwent a retroperitoneal lymphadenectomy and 15 months after the surgery, has had no signs of primary tumours or metastasis. This case reports on a rare instance of metastatic RCC without an identified primary renal malignancy.

Safety and efficacy of laparoscopic transperitoneal versus retroperitoneal resection for benign retroperitoneal tumors: a retrospective cohort study

BACKGROUND AND OBJECTIVE

Benign retroperitoneal tumors (BRTs) are clinically rare solid tumors. This study aimed to compare the safety and efficacy of laparoscopic transperitoneal versus retroperitoneal resection for BRTs.

METHODS

The clinical data of 43 patients who had pathologically confirmed BRTs and underwent laparoscopic resection in a single center from January 2019 to May 2022 were retrospectively analyzed. Patients were divided into two groups according to the surgical methods: the Transperitoneal approach group (n = 24) and the Retroperitoneal approach group (n = 19). The clinical characteristics and perioperative data between the two groups were compared. The baseline data and surgical variables were analyzed to determine the impact of different surgical approaches on the treatment outcomes of BRTs.

RESULTS

No significant difference was observed between the two groups in gender, age, body mass index, the American Society of Anesthesiologists score, presence of underlying diseases, tumor size, tumor position, operation duration, intraoperative hemorrhage, postoperative hospital stay, intestinal function recovery time, and postoperative complication rate. The conversion rate from laparoscopic to open surgery was significantly lower in the Transperitoneal approach group than in the Retroperitoneal approach group (1/24 vs. 5/19, χ2 = 4.333, P = 0.037). Tumor size was an independent influencing factor for the effect of surgery (odds ratio = 1.869, 95% confidence interval = 1.135-3.078, P = 0.014) and had a larger efficacy on the retroperitoneal group (odds ratio = 3.740, 95% confidence interval = 1.044-13.394, P = 0.043).

CONCLUSION

The laparoscopic transperitoneal approach has the inherent advantages of anatomical hierarchies and surgical space, providing a better optical perspective of the targeted mass and improved bleeding control. This approach may have better efficacy than the retroperitoneal approach, especially in cases of a large tumor or when the tumor is located near important blood vessels.

Retroperitoneal urothelial carcinoma arising after bladder diverticulectomy: a case report

BACKGROUND

Urothelial carcinoma arises from the inner urothelial membrane of the renal pelvis, ureter, and bladder and often causes macrohematuria. Here, we report a rare case in which the patient developed non-symptomatic urothelial carcinoma anatomically outside the bladder wall 17 years after bladder diverticulectomy.

CASE PRESENTATION

An 82-year-old male patient previously underwent gastrectomy for stomach cancer and partial hepatectomy for intrahepatic cholangiocarcinoma. Follow-up computed tomography revealed a tumor in the retroperitoneal space, where a bladder diverticulum was removed 17 years earlier. Multiparametric magnetic resonance imaging suggested that the tumor was malignant with rectal invasion. Subsequent computed tomography-guided percutaneous biopsy revealed that the tumor was urothelial carcinoma. The patient underwent two courses of neoadjuvant chemotherapy followed by pelvic exenteration with pelvic lymph node dissection. He is currently receiving adjuvant therapy with an immune checkpoint inhibitor and has had no recurrence for 3 months.

CONCLUSIONS

Multiparametric magnetic resonance imaging is a helpful tool for predicting both tumor malignancy and invasion before a pathologically confirmed diagnosis. Although this case is rare, urologists should be aware of the occurrence of urothelial carcinoma after bladder diverticulectomy in cases of incomplete resection of the diverticulum.

Case Report: Adrenal glands degenerated schwannoma: Report of three cases and literature review

Background

Schwannoma is a benign tumor, of which degenerated schwannoma is a subtype. Retroperitoneal schwannomas are extremely rare, as they account for only 3% of retroperitoneal tumors.Degenerated schwannoma is a schwannoma subtype. However,degenerated schwannoma occurring in the adrenal glands is extremely rare.

Case summary

Case 1: A 42-year-old man was referred to our hospital for further examination of a left adrenal mass that was incidentally discovered during a routine physical check-up.No significant abnormalities were found in laboratory tests results. Robotic-assisted laparoscopic excision of the left adrenal gland was performed under general anesthesia. Case 2: A 47-year-old man was admitted to the hospital because of a left adrenal mass found on a routine physical examination.The patient was previously in good health, and there was no family history of a similar disorder. Left-sided laparoscopic adrenalectomy was performed under general anaesthesia. Case 3: A 62-year-old woman with hypertension and diabetes mellitus was referred to our hospital after an incidentally found left adrenal mass.There was no family history of a similar disorder. Left-sided laparoscopic adrenalectomy was performed under general anaesthesia. None of the patients had a recurrence in our study during the postoperative follow-up.

Conclusion

Degenerated schwannoma of the adrenal glands is very rare. The clinical presentations of degenerated schwannoma are nonspecific; a small number of patients do not have any symptoms, and the mass is only found incidentally during physical examination for any number of reasons. The preoperative diagnosis of adrenal degenerated schwannoma is difficult because the diagnosis must rely on pathological examination and immunohistochemistry assays. The management is surgical excision and regular follow-up.