A rare case of giant retroperitoneal neurilemmoma

Paravertebral retroperitoneal ancient schwannoma mimicking irritable bowel syndrome

We report a case of paravertebral retroperitoneal ancient schwannoma (RPAS) with symptoms suggestive of irritable bowel syndrome that was relieved after resection. Very few cases have been reported of RPAS with gastrointestinal symptoms. Increased bowel activity associated with RPAS has not been reported. Our case report suggests that RPAS may present with increased bowel frequency that could be relieved after surgical resection.

Successful management of a giant retroperitoneal ancient schwannoma mimicking malignant tumors: A case report and literature review

Introduction and Importance

Schwannomas, originating from Schwann cells surrounding nerve sheaths, tend to be slow-growing. Among these, giant ancient schwannomas are remarkable for their rare occurrence and their capacity for substantial growth and regressive changes. Furthermore, the expansiveness and flexibility of the retroperitoneal space often conceal the symptoms of retroperitoneal schwannomas, leading to delayed diagnosis and allowing these tumors to grow significantly and become large and long-standing before detection.

Case Presentation

A 24-year-old man presented with left flank pain and a growing abdominal bulge in the left upper quadrant. Computed tomography scan revealed a 15×15×10 cm lytic expansile lesion. Consequently, the encapsulated mass was surgically excised and diagnosed as an ancient retroperitoneal schwannoma through histological and immunohistochemical studies.

Clinical Discussion

Comprehensive preoperative planning and a multidisciplinary strategy are imperative for the complete excision of schwannomas. These tumors can present diagnostic complexities, particularly due to nuclear atypia and pleomorphism, which might lead to misinterpretation regarding malignancy. Despite the risks associated with percutaneous biopsies, the low mitotic count is a critical diagnostic factor. Our study underscores the consensus that the definitive diagnosis should rely on postoperative histopathological findings, highlighting the importance of accurate assessment.

Conclusion

Rare giant retroperitoneal ancient schwannomas pose diagnostic challenges due to their rarity, lack of distinct symptoms, and atypical locations. This study presents a successful case and management.

Imaging in gynecological disease (26): clinical and ultrasound characteristics of benign retroperitoneal pelvic peripheral-nerve-sheath tumors

OBJECTIVE

To describe the clinical and sonographic characteristics of benign, retroperitoneal, pelvic peripheral-nerve-sheath tumors (PNSTs).

METHODS

This was a retrospective study of patients with a benign, retroperitoneal, pelvic PNST who had undergone preoperative ultrasound examination at a single gynecologic oncology center between 1 January 2018 and 31 August 2022. All ultrasound images, videoclips and final histological specimens of benign PNSTs were reviewed side-by-side in order to: describe the ultrasound appearance of the tumors, using the terminology of the International Ovarian Tumor Analysis (IOTA), Morphological Uterus Sonographic Assessment (MUSA) and Vulvar International Tumor Analysis (VITA) groups, following a predefined ultrasound assessment form; describe their origin in relation to nerves and pelvic anatomy; and assess the association between their ultrasound features and histotopography. A review of the literature reporting benign, retroperitoneal, pelvic PNSTs with preoperative ultrasound examination was performed.

RESULTS

Five women (mean age, 53 years) with a benign, retroperitoneal, pelvic PNST were identified, four with a schwannoma and one with a neurofibroma, of which all were sporadic and solitary. All patients had good-quality ultrasound images and videoclips and final biopsy of surgically excised tumors, except one patient managed conservatively who had only a core needle biopsy. In all cases, the findings were incidental. The five PNSTs ranged in maximum diameter from 31 to 50 mm. All five PNSTs were solid, moderately vascular tumors, with non-uniform echogenicity, well-circumscribed by hyperechogenic epineurium and with no acoustic shadowing. Most of the masses were round (n = 4 (80%)), and contained small, irregular, anechoic, cystic areas (n = 3 (60%)) and hyperechogenic foci (n = 5 (100%)). In the woman with a schwannoma in whom surgery was not performed, follow-up over a 3-year period showed minimal growth (1.5 mm/year) of the mass. We also summarize the findings of 47 cases of benign retroperitoneal schwannoma and neurofibroma identified in a literature search.

CONCLUSIONS

On ultrasound examination, no imaging characteristics differentiate reliably between benign schwannomas and neurofibromas. Moreover, benign PNSTs show some similar features to malignant retroperitoneal tumors. They are solid lesions with intralesional blood vessels and show degenerative changes such as cystic areas and hyperechogenic foci. Therefore, ultrasound-guided biopsy may play a pivotal role in their diagnosis. If confirmed to be benign PNSTs, these tumors can be managed conservatively, with ultrasound surveillance. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Pediatric retroperitoneal non-organ-originated malignancies: An analysis based on SEER database

Retroperitoneal non-organ-originated malignancies are rare pediatric tumors with challenging diagnosis and treatment. The present study aimed to analyze the clinicopathological characteristics, treatment, and prognosis of retroperitoneal non-organ-originated malignancies. In the study, we included the pathological diagnosis of pediatric retroperitoneal non-organ-originated malignant tumors between 2000 to 2019 through the updated Surveillance, Epidemiology, and End Results database. We use the Kaplan-Meier survival curve to calculate the overall survival (OS) and cancer-specific survival (CSS). The risk of all-cause death and disease-specific death were analyzed using Cox proportional hazard regression model and Fine-and-Grey competitive hazard model, respectively. In the study, a total of 443 pediatric retroperitoneal non-organ-originated malignancies were included. Of them, only 22.3% of patients had no metastatic disease, 42.9% had distant metastasis and 34.8% had locally advanced diseases. The primary pathological tumor was neuroblastoma followed by germ cell tumor. The overall 10-year OS and CSS were 70.7% and 73.1%, respectively, and the 10-year OS and CSS of metastatic diseases were 54.4% and 56.6%, respectively. Older children, worse tumor stage at diagnosis, incomplete resection, and prolonged time from diagnosis to treatment were significantly associated with worse survival outcomes. Radiotherapy and chemotherapy did not significantly improve the prognosis of patients without complete tumor resection. The study indicated that most pediatric retroperitoneal non-organ-originated malignancies diagnosed with metastatic diseases have plagued treatment. Radiotherapy and chemotherapy are the main treatment methods for children unable to undergo complete surgical treatment. However, these treatments do not reach the same therapeutic effect as complete tumor resection after early diagnosis. Hence, early diagnosis and surgery for complete tumor resection are of utmost importance.

Retroperitoneal schwannoma: Uncommon location of a benign tumor

Schwannoma is a type of nerve tumor of the nerve sheath. They are preferentially localized on the head, neck, and flexor surfaces of the extremities. Retroperitoneal schwannoma is extremely rare. The diagnosis is uncommon and based on the anatomopathological and immunochemistry examination of the surgical specimen. We herein report an uncommon location of schwannoma treated with conventional surgery in a 53‐year‐old female patient admitted to our department for chronic abdominal pain. Retroperitoneal schwannoma is a rare disease that occurs in adult females. The histopathological examination is the only reliable examination for the diagnosis after total surgical resection.