Laparoscopic resection of a retroperitoneal schwannoma behind the lesser omental sac

Laparoscopic retroperitoneal resection of the duodenal gastrointestinal stromal tumors in neurofibromatosis type 1; Case Report and literature review

Background

Neurofibromatosis type 1, also known as NF1, is a disorder that is passed down in an autosomal dominant manner. It manifests in a wide variety of tumors and affects several organ systems. It is expected that those carrying the NF1 gene will develop a rare mesenchymal tumor known as a gastrointestinal stromal tumor (GIST) more than general population.

Case report

This research discusses a 42-year-old female patient with NF1 who was identified with a duodenal GIST but clinically and radiographically misinterpreted as having a retroperitoneal neurofibroma. She had minimally invasive retroperitoneal laparoscopic surgery to remove the tumor and primary anastomosis of the affected duodenal wall. A spindle cell GIST was entirely excised during surgery, as indicated by the pathologist. As a consequence of dialogue at a multidisciplinary team meeting, the patient was discharged from the hospital on the fourth postoperative day and is presently undergoing regular clinical follow-up.

Conclusion

Anatomically problematic sites, such as the duodenal GIST in NF1 patients, can be treated safely with the laparoscopic retroperitoneal approach even when retroperitoneal neoplasia arises from the intrabdominal structure and protrudes into the retroperitoneal region.

Total laparoscopic resection by medial-retroperitoneal approach using virtual navigation: two case reports of primary retroperitoneal schwannoma

Background

We report two rare cases of retroperitoneal schwannoma completely resected by a laparoscopic medial-retroperitoneal approach aided by virtual navigation. Three-dimensional images have been used in liver and lung surgery, but there are few prior reports on retroperitoneal surgery.

Case presentation

These two case reports are of a 60-year-old man and a 40-year-old man with asymptomatic retroperitoneal schwannoma. In both cases, the tumors were located in the right renal hilum and were close to the duodenum, right ureter, and inferior vena cava. Simulation using three-dimensional images was performed before surgery, and a medial-retroperitoneal approach was performed to secure a wide surgical field. During the operation, we confirmed the location of the main feeder and the relationship between the tumor and organs with those shown on the three-dimensional images and performed total laparoscopic resection.

Conclusion

The medial-retroperitoneal approach provides operative safety. Preoperative simulation and intraoperative navigation with three-dimensional images, which can be freely rotated and interactively visualized from any angle, are useful methods to enhance the surgeon’s understanding of a patient’s specific anatomy and are especially effective when resecting a retroperitoneal tumor that is located in an anatomically deep and complex location.

An interdisciplinary approach for laparoscopic removal of a large retroperitoneal pelvic schwannoma attached to vital vessels: A case report

RATIONALE

Retroperitoneal schwannomas are very rare and may grow very close to major abdominal vessels. Since the surgical approach to the retroperitoneal space may be complex due to surrounding vital organs, including major vessels, laparoscopic surgery is challenging and has only been recently adopted. Here, we report a case of laparoscopic resection of a large retroperitoneal schwannoma attached to large vital vessels.

PATIENT CONCERNS

A 62-year-old woman presented with a chief complaint of pain in the lower right limb with consequent claudication, which had lasted for approximately 1 year.

DIAGNOSES

Magnetic resonance imaging revealed a solid oval mass measuring 45 × 32 × 39 mm, located medially to the right iliopsoas muscle at the level of the intersomatic space between the 5th lumbar vertebra and the 1st sacral vertebra. This mass was inhomogeneously hypointense in T2 due to the presence of cystic areas, with intense and inhomogeneous contrast enhancement, compatible with the diagnosis of a schwannoma. The mass compressed the inferior caval vein near its bifurcation and the right common iliac vein, anteriorly dislocating the ipsilateral iliac arterial axis.

INTERVENTIONS

A multidisciplinary team skilled in vascular and pelvic laparoscopy was involved. The patient underwent laparoscopic surgery via an anterior transperitoneal approach with right adnexectomy and radical excision of the tumor. The surgery lasted 120 minutes without intraoperative complications. Blood loss was less than 100 mL. The histologic diagnosis was a benign Schwannoma; grade I according to World Health Organization classification.

OUTCOMES

The postoperative course was uneventful. At the 10-month follow-up, the patient had no recurrences and was asymptomatic.

LESSONS

Laparoscopic removal of large retroperitoneal schwannomas, even if attached to major vital vessels, is feasible and safe when performed by experienced surgeons.

Laparoscopically excised retroperitoneal presacral Schwannoma: atypical pre and postoperative manifestations - case report

BACKGROUND

We are a reporting a rare case of retroperitoneal schwanomma with atypical pre and postoperative manifestations. Retroperitoneal schwannomas are rare tumors that are difficult to preoperatively diagnose.

CASE PRESENTATION

This is a case report of a male patient, 41 years old, with symptoms of hipogastric and lower right member pain, as well as a history of a papilliferous thyroid tumor. Computerized tomography exams were inconclusive, showing a mass in the presacral region with dimensions of 4.4 × 3.9 × 3.4 cm. Removal was carried out by laparoscopic surgery, with self-limited postoperative complications. Diagnosis was carried out by anatomopathological examination, and syndromic hypotheses were discarded.

CONCLUSIONS

The postoperative complications of schwanomma are little reported in the literature. In the simultaneous occurrence of schwanomma and other endocrine tumors, further studies are warranted to better differentiate the cases that need investigation of syndromic causes.

Laparoscopic resection of a retroperitoneal schwannoma located in the hepatic hilus

Schwannomas are tumors and commonly occur in the head and neck region; however, they rarely present in the retroperitoneum. A 79-year-old man was admitted to our hospital for a follow-up of a tumor in the hepatic hilus. A 2.8 × 2.5 cm solid tumor located between the hepatic hilus and common hepatic artery was originally identified, and the size of the tumor had increased from 2.0 × 2.0 cm to 2.8 × 2.5 cm over the course of 3 years. The patient underwent percutaneous sonopsy, and the tumor was subsequently diagnosed as a benign schwannoma. Since the patient wished to undergo an operation, we performed laparoscopic surgery. During the operation, the tumor was detected in the retroperitoneal space, where it was strongly adhered between the left gastric artery and common hepatic artery. At this point, no major vessels had vascularized the tumor. We then completely removed the tumor from the retroperitoneal space without any complications. The clinical course was uneventful, and the patient was discharged on postoperative day 4 without any symptoms. Later, a definitive histopathologic examination revealed a benign schwannoma. Here, we report this rare case of a retroperitoneal schwannoma located in the hepatic hilus.

Retroperitoneal schwannomas: advantages of laparoscopic resection. Review of the literature and case presentation of a large paracaval benign schwannoma (with video)

Retroperitoneal schwannomas represent 0.5%-3% of all retroperitoneal tumors. Complete surgical removal is the treatment of choice because it permits a correct histological diagnosis and prevents eventual degeneration. Laparoscopic surgery has been reported as safe and effective by several authors. We present a comprehensive review of the literature regarding the role of laparoscopy in surgical resection of retroperitoneal schwannomas, and we present a case showing the technique (with video). Laparoscopic resection in experienced hands is safe and effective, and guarantees excellent postoperative results in terms of patient recovery.

Retroperitoneal schwannomas in the anterior pararenal space: dynamic enhanced multi-slice CT and MR findings

BACKGROUND

To evaluate the imaging features of schwannomas in the anterior pararenal space (APS), especially focusing on dynamic enhanced multi-slice CT (MSCT) and MR findings.

PATIENTS AND METHODS

Eight patients with pathologically proved retroperitoneal schwannomas in the APS underwent dynamic enhanced multi-slice CT (MSCT), while three of these patients also had a contrast-enhanced MR examination. The imaging findings were retrospectively reviewed.

RESULTS

All eight cases exhibited forward displacement of the pancreas, and three cases showed lateral displacement and compression of the inferior vena cava. The tumors had round or oval shape with a maximal axial diameter of 4.0-12.3 cm (average, 6.7 cm). All eight tumors were solitary and well circumscribed. Of the eight retroperitoneal schwannomas in the APS, six exhibited a capsule with thickness of 1.0-2.0 mm, one showed punctate calcification, two displayed cystic degeneration, and three revealed a "target sign" on CT and MR. The tumors were hypo-dense on unenhanced CT images, hyper-intense on T2W images, and homogeneously hypo-intense on T1W images. All eight tumors exhibited gradual enhancement on dynamic enhanced CT or MR images. One case showed delayed enhancement. Heterogeneous enhancement was the dominant pattern occurring in seven out of eight tumors.

CONCLUSION

The imaging findings of schwannoma in the APS correspond with its pathological composition. Schwannoma should be included in the differential diagnosis of tumors in the APS.

Pelvic schwannoma in the right parametrium

Neurilemomas are benign usually encapsulated nerve sheath tumors derived from the Schwann cells. These tumors commonly arise from the cranial nerves as acoustic neurinomas but they are extremely rare in the pelvis and the retroperitoneal area (less than 0.5% of reported cases), unless they are combined with von Recklinghausen disease (type 1 neurofibromatosis). We report the case of a 58-year-old female with pelvic schwannoma, 6.5 × 5.5 cm in size, in the right parametrium. This is the first case reported in the literature. Based on the rarity of this tumor and in order to ensure optimum treatment and survival for our patient, we performed laparotomy with total abdominal hysterectomy and en-block tumor excision. A frozen section was taken during the surgery before complete resection of the mass, which was ambiguous. Because of the possibility of malignancy, complete excision of the mass was performed, with pelvic blunt dissection. Histological examination showed a benign neoplasm, originating from the cells of peripheral nerve sheaths; diagnosis was a schwannoma. There were degenerative areas, including cystic degeneration, hemorrhagic infiltrations, ischemic foci with pycnotic cells, and collagen replacement. Pelvic schwannomas are rare neoplasms that can be misdiagnosed. Laparoscopy is a safe and efficient option for approaching benign pelvic tumors and might offer the advantage of better visualization of structures due to the magnification in laparoscopic view, especially in narrow anatomic spaces.

Laparoscopic management of obturator nerve schwannomas: experiences with 6 cases and review of the literature

OBJECTIVES

To present our experiences in management of obturator nerve schwannomas by laparoscopy.

PATIENTS AND METHODS

Six patients who were diagnosed preoperatively with pelvic tumors and histologically with obturator nerve schwannomas were treated by laparoscopy in our hospital between 1998 and 2009. Clinical data were obtained by a retrospective review of all the patients' medical records, radiologic reports, pathologic reports, and operation videos.

RESULTS

A total of 6 tumors were found in 6 patients, none of which was correctly, preoperatively diagnosed as a schwannoma. In 5 of them, obturator nerve roots were identified to be associated with the tumors during the operation. All of the tumors were resected successfully by laparoscopy, including 2 resected by enucleation. Postoperatively, 2 patients developed a permanent neurological deficit, 2 patients developed transient nerve neuropathy but complete resolution within 8 weeks, and the other 2 developed no neurological deficit. Pathologic examination showed that all the tumors were benign schwannoma. At a mean follow-up of 24 months (range, 12 to 48 mo) postresection, all the patients remained free from recurrence.

CONCLUSIONS

Pelvic schwannomas are rare and difficult to diagnose preoperatively. The intraoperative observation of the nerve running through the tumor may aid the diagnosis. Although obturator nerve injury does not seem to be associated with severe impairments, efforts should be made to preserve the integrity of the nerve. Laparoscopic surgery is a safe and feasible method for approaching benign schwannoma in the obturator fossa.

Laparoscopic resection of ancient schwannoma embedded in the psoas muscle

Schwannoma is a tumor originating from the Schwann cell of the peripheral nerve sheath. The diagnosis of schwannoma is based on histologic analysis of surgically excised sample. Retroperitoneal ancient schwannoma, a variant of schwannoma, is rarely observed in clinical practice. We report the case of a 46-year-old man with a retroperitoneal tumor embedded in the psoas muscle, which was treated by laparoscopic resection. The operative result was good, and pathologic analysis revealed a 5.5 × 4.5 cm ancient schwannoma.

Laparoscopic resection of a retroperitoneal schwannoma

Herein is a report of a case of a 34-year-old man whose chief complaint was right lower abdominal pain. He was diagnosed with acute appendicitis. Additionally, an abdominal CT scan found retroperitoneal tumor approximately 5 cm in size, with an imaging effect, located adjacent to the dorsal side of the inferior vena cava. For this suspected neurogenic tumor, laparoscopic appendectomy and retroperitoneal tumorectomy were performed after conservative treatment of appendicitis. The retroperitoneal tumor was 5.5 × 3.5 cm in size, had a capsule, smooth surface and soft elasticity, and the divided face was solid white. The histopathological work-up revealed that the tumor was a benign mixed-type schwannoma, in which spindle cells were arranged. The patient's postoperative course was uneventful, and he was discharged from the hospital 7 days after the surgery. In general, retroperitoneal schwannoma is not associated with any symptoms, so it is often discovered accidentally, as in this case. The appropriate treatment for the condition is surgical resection of the tumor including the capsule. However, the use of laparoscopic surgery has been reported in recent years. Although the majority of the cases are benign, there have been some reports of local recurrence. As such, this case will required careful follow-ups.

Three cases of retroperitoneal schwannoma diagnosed by EUS-FNA

Schwannomas are peripheral nerve tumors that are typically solitary and benign. Their diagnosis is largely based on surgically resected specimens. Recently, a number of case reports have indicated that retroperitoneal schwannomas could be diagnosed with endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). We report the diagnosis of three cases of schwannoma using EUS-FNA. Subjects were two males and one female, ages 22, 40, and 46 years, respectively, all of whom were symptom-free. Imaging findings showed well-circumscribed round tumors. However, as the tumors could not be diagnosed using these findings alone, EUS-FNA was performed. Hematoxylin-eosin staining of the resulting tissue fragments revealed bland spindle cells with nuclear palisading. There was no disparity in nuclear sizes. Immunostaining revealed S-100 protein positivity and all cases were diagnosed as schwannomas. Ki-67 indexes were 3%-15%, 2%-3%, and 3%, respectively. No case showed any signs of malignancy. As most schwannomas are benign tumors and seldom become malignant, we observed these patients without therapy. All tumors demonstrated no enlargement and no change in characteristics. Schwannomas are almost always benign and can be observed following diagnosis by EUS-FNA.

[A case of a retroperitoneal schwannoma presenting as hypermetabolic mass in PET-CT]

Schwannoma is a benign neoplasm of the Schwann cells of the neural sheath. Most schwannomas occur in the head and neck, and extremities and rarely in the retroperitoneal space. The differentiation of a schwannoma from other malignant tumor or benign tumor is very difficult on a preoperative examination with ultrasonography, computed tomography or magnetic resonance imaging. Furthermore, the lesion with increased fluorodeoxyglucose uptake in PET-CT cannot exclude malignant tumor. Therefore, this lesion needs surgical excision and a histological examination with immunohistochemical staining. We report a case of schwannoma occuring in the retroperitoneal space that incidentally discovered by PET-CT for health-check up. Pathologic confirmation by laparoscopic excision was done.

Laparoscopic excision of retroperitoneal tumors: report of three cases

Retroperitoneal neural tumors are rarely excised laparoscopically, with fewer than ten cases reported in the literature. Between February 2005 and December 2007, we performed successful planned laparoscopic excision of retroperitoneal tumors using the four-trocar technique in three patients. All three patients were women, with a mean age of 40.7 years. The mean tumor size was 4.8 cm. The mean operative time was 126 min and the mean blood loss 14.3 ml. The postoperative pathological diagnosis was schwannoma in one patient and ganglioneuromas in two. There was no morbidity or mortality. Although difficult to diagnose preoperatively, neural tumors in the retroperitoneal space are most often benign, with a good prognosis. Laparoscopic surgical techniques for retroperitoneal tumors are safe, and their use is encouraged when an appropriate diagnosis is made, after exclusion of malignant subtypes.

Perirenal venous aneurysm presenting as retroperitoneal tumor treated successfully by laparoscopic excision

We describe an unusually located venous aneurysm found incidentally in a 46-year-old man that was presumptively diagnosed as a retroperitoneal mass near the left renal hilum. He presented for constipation and weight loss; an abdominal ultrasound scan disclosed an anechoic lesion in the left retroperitoneum. Abdominal CT showed a 3-cm mass with low density located at the junction of the left para-aortic and perirenal hilar regions that was initially suspected of being metastatic lymphadenopathy with an unknown primary origin or a neurogenic tumor. The mass was resected by a laparoscopic approach, which revealed a round mass with a smooth capsule and roots connecting to the paraspinal muscles. On pathologic examination, the mass showed classic features of a venous aneurysm. At 12-month follow-up, no local recurrence or malignancy was documented.

Evaluation of perinephric, retroperitoneal schwannomas: case report and review of the literature

Schwannomas are tumors arising from the nerve sheath. Because of their infrequent occurrence, nonspecific symptoms, and lack of distinguishing radiologic features, schwannomas are most often diagnosed histologically after surgical excision. We report herein a case of a perinephric, retroperitoneal schwannoma which, after evaluation by computed tomography, magnetic resonance, and angiography, appeared to be a renal cell carcinoma arising from the left kidney. The diagnosis of benign retroperitoneal schwannoma was made by histologic examination and immunohistochemical staining of the excised mass. A practical algorithm for perinephric, retroperitoneal schwannomas is proposed.

[Benign retroperitoneal schwannoma. Incidental diagnostic in patient with hematuria of the percusionist]

The incidence of retroperitoneal primitive tumour varies from the 0.3 to 3%. The sarcomas suppose the group but it frequents of retroperitoneal tumour, being the Schwannoma an unusual tumour with an incidence from 1% to 50% of the retroperitoneal primary tumours. The schwannoma also denominated neurinoma or neurolenoma, it is a derived tumour of the cells of Schwann of the outlying nerves. It is characterized by their clinical and radiological inespecify, being the diagnose pathological, with intense positive inmunohistoquimics to the protein S-100. The election treatment is the surgical remove, with wide margins; not being described cases of malignización neither of metastasis at distance, but if the recurrence existence at probably secondary local level to incomplete resection.