Retroperitoneal schwannoma: case series and literature review

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.

Retroperitoneal ancient schwannoma presenting as left flank pain and moderate unilateral hydronephrosis: A case report and literature review

Key Clinical Message

Benign ancient retroperitoneal schwannomas (BARS) exhibit abdominal masses and flank pain to incidental findings at more advanced stages. Histopathological and immunohistochemical analysis is essential for confirmation of benign nature. Our patient was misdiagnosed as ureteric colic, highlighting the need to consider BARS in differential diagnosis to prevent complications like hydronephrosis.

Abstract

Ancient schwannomas are usually benign neoplasms that originate from Schwann cells of peripheral nerves. We present a novel case of a 24-year-old young male with left flank pain and nausea which was initially thought to be left ureteric colic. However, in-depth imaging and biopsy revealed a retroperitoneal mass. The definitive diagnosis was narrowed down to Benign Retroperitoneal Ancient Schwannoma (BARS) via immunohistochemistry and histopathological analysis. This often marble-shaped S100 protein-positive tumor is an under-recognized and potential cause of hydronephrosis if localized near the renal structures. In addition, the retroperitoneal location with infrarenal abdominal aortic adherence is another rare peculiarity in the present case that demands prompt diagnosis and surgical excision to avoid any cardiovascular sequelae such as hypotension and abdominal pain, as indicated by the natural history of growth of this benign tumor. Therefore, timely excision of this benign tumor prior to its further proliferation is paramount. We initially planned laparoscopic removal but adopted excision via laparotomy because of the proximity of the vital structures. The postoperative course of the patient was uneventful and subsequently the patient's presenting complaint of left abdominal flank pain greatly improved. The patient was advised to undergo follow-up computed tomography scan of kidney ureter bladder and RFT evaluation 6 months postsurgery which indicated no evidence of recurrence or iatrogenic complications. The diagnosis and management of the present case share valuable experiences for similar future cases worldwide.

A giant pelvic infiltrating schwannoma misdiagnosed as an ovarian neoplasm that was resected using a laparoscopic approach: A case report

Introduction and importance: Large retroperitoneal schwannomas are rare and present significant challenges in surgical management, particularly when located in the pelvic region. Gynecologists can encounter rare problems when a pelvic schwannoma is mistaken for an adnexal pathology. Case Presentation: A 62-year-old woman presented with a giant retroperitoneal mass suspected of a potentially malignant ovarian tumor preoperatively. Computed tomography revealed a large mixed solid-cystic mass near the right adnexa measuring 118 × 100 × 80 mm. The cancer antigen 125 level was 196 U/mL. We performed a diagnostic-operative laparoscopy, which showed a retroperitoneal neoformation below the cava and aortic bifurcation adherent to the sacrum, right pelvic vessels, and hypogastric nerve up to the vagina. We carefully detached the mass from the nearby tissues using the most appropriate laparoscopic devices. The entire neoplasm was removed through the vagina into a surgical bag. The surgery lasted 180 min without complications. Histology revealed a grade I benign schwannoma. At the 12-month follow-up, the patient was asymptomatic without signs of recurrence. Clinical Discussion: Pelvic retroperitoneal schwannomas can mimic ovarian carcinomas; misdiagnosis may occur due to their rarity and the difficulty of interpreting preoperative imaging. In case of unexpected giant presacral schwannomas surgical management is challenging due to their peculiar location. Conclusion: This case underscores the need for a skilled, experienced team of gynecological oncologists to achieve favorable outcomes when performing laparoscopic surgery of giant pelvic retroperitoneal schwannoma. Adequate knowledge of the complex pelvic anatomy, careful surgical planning, and familiarity with the most appropriate surgical tools are critical points.

Adrenal Schwannoma: Case Description and Diagnostic Pointers of a Rare Disease

Benign nerve sheath tumours such as schwannomas commonly involve the peripheral and cranial nerves. A schwannoma in the adrenal gland is a very rare occurrence, which arises from the adrenal medulla. Its most common presentation is a non-functional incidentaloma. It does not have any unique imaging characteristic distinguishing it from other adrenal masses; hence, its diagnosis is usually confirmed by final histopathology. In this report, we present two cases of an adrenal schwannoma for which we anticipated an unusual diagnosis, which was confirmed through adrenalectomy on histopathology.

Malignant psammomatous melanotic schwannoma mimicking adrenal cyst: case report

Background

Melanotic schwannoma is a melanin producing nerve sheath tumors. Rarely, it can be associated with psammoma bodies, called psammomatous melanotic schwannoma. Psammomatous melanotic schwannomas are associated in up to 10% of the cases with Carney’s syndrome. The rarity of the lesion, which may present at different localizations create difficulty in placing a correct initial diagnosis. Definitive diagnosis is made after complete tumor excision and pathomorphological evaluation. The prognosis depends on the anatomical localization, local invasion and presence of a high mitotic index. The main pathomorphological differential diagnosis includes schwannomas and other melanin producing tumors as melanoma.

Case presentation

We present a case of an 11-year-old female with cystic lesion adjacent to right adrenal gland, mimicking adrenal cyst. Ultrasound guided biopsy was undertaken due to the cystic appearance of the formation and the lack of certain diagnosis from the non-invasive diagnostic tests. No signs of cellular and nuclear atypism were observed. The diagnosis of benign endothelial cyst with spontaneous hemorrhage was suggested. The patient underwent transabdominal laparoscopic adrenalectomy en-bloc with the cyst to prevent spillage of the cyst content due to the intimate adhesion of the lesion to the adrenal gland and vena cava inferior. Pathomorphological examination revealed malignant psammomatous melanotic schwannoma. The adrenal gland was intact with no tumor infiltration. The patient was followed up on the 1st and 2nd month afterwards the surgery by MRI with no signs of local recurrence and postoperative complications.

Conclusion

Psammomatous melanotic schwannoma near adrenal gland are rare and present difficulty with exact preoperative diagnosis. Complete resection should always be provided. Laparoscopic surgery is feasible if radical excision is not compromised. Long-term follow-up and Carney’s syndrome surveillance after complete excision are recommended especially in young patients.

Huge adrenal schwannoma: a rare type of adrenal tumor, misconceived as adrenocortical carcinoma

Schwannoma is a benign and uncommon neoplasm arising from the neural crest cells. The most common tumor sites are the skin and subcutaneous tissue of the head and neck. Retroperitoneal schwannomas account for 1–3% of all schwannomas and are predominantly female. In particular, adrenal schwannoma is very rare, and due to its large size at the time of diagnosis, adrenal schwannoma is frequently misdiagnosed as adrenocortical carcinoma or pheochromocytoma. Adrenal schwannoma is difficult to distinguish it from other adrenal diseases based on imaging findings alone. In this report, we introduce the case of a huge left adrenal schwannoma.

Retroperitoneal cystic schwannoma mimics liquefied hematoma

Schwannomas are nerve sheath tumors that seldom occur in the retroperitoneal region. Herein, we describe an incidentally detected retroperitoneal schwannoma that mimicked liquefied hematoma on computed tomography. A 61-year-old man was admitted to the emergency department with chest pain caused by a fall at a construction site. Chest computed tomography incidentally revealed a retroperitoneal cystic mass measuring 10 cm, in addition to multiple rib fractures and hemopneumothorax. The patient frequently consumed alcohol and had a history of repeated trauma; therefore, we considered the following 2 conditions: retroperitoneal cystic tumor and liquefied hematoma. He underwent complete surgical excision, and a histopathological examination confirmed the mass as a schwannoma. Experience and knowledge regarding the computed tomography findings of retroperitoneal cystic schwannoma are useful for the differential diagnosis of infrequent retroperitoneal tumors.

Rare case of pelvic schwannoma mimicking intra-ligamenter uterine fibroid: A case report

INTRODUCTION AND IMPORTANCE

Schwannomas are benign tumors originating from Schwann cells of nerve fibers. Pelvic schwannomas are extremely rare. Here, we present a case of a 48-year-old woman with a pelvic schwannoma imitating degenerating cystic leiomyoma.

CASE PRESENTATION

A 48-year-old woman presented with brown-yellowish bloody vaginal discharge, fever, abdominal enlargement, and pain. Abdominal ultrasound showed a homogeneous solid mass with a clear border separated from the uterus and left ovary. Computed tomography (CT) scan revealed a multilocular cystic mass with thick septa and solid enhancing component. Histopathological examination showed a mesenchymal tumor composed of cells with fine chromatin. The nuclei were oval or round, and some cells exhibited spindle and cigar-shaped nuclei. Tumor cells had an abundant amount of eosinophilic cytoplasm. Immunohistochemical examination demonstrated positive expression for S100 as specific staining for schwannomas. Mitosis was not found, and hyalinized blood vessels were observed.

CLINICAL DISCUSSION

Compression by the tumor into the surrounding organs, such as the bladder and intestines, could cause difficulty with defecation and urination in patients. The absence of specific signs and symptoms can lead to a misdiagnosis of pelvic schwannoma. Surgery is the treatment of choice. It is difficult to establish a definitive diagnosis before surgery. Laparotomy approach was taken and a histopathological examination was completed to confirm the diagnosis.

CONCLUSION

Unspecified pelvic pain with abdominal mass may suggest a rare tumor such as schwannoma. Transvaginal ultrasonography is incapable of reliably distinguishing between schwannoma and other tumors.

Surgery of neurogenic tumors of the sacrum

OBJECTIVES

Our objective is to share our experience in neurogenic tumors of the sacral area, an uncommon disease, and assess approaches, intraoperative techniques, complications and clinical course of patients in a case series.

METHODS

We conducted a retrospective analysis of 19 cases of patients with neurogenic tumors in the sacral area who were diagnosed and underwent surgery at our center. Of them, 8 were male and 11 were female. They had a mean age at diagnosis of 51 years (with an age range of 25-78 years). Six patients were asymptomatic and were diagnosed incidentally, while the majority (11 patients) presented with lumbar pain accompanied by other symptoms: pain radiating to the legs, pelvic pain, sensory alterations and loss of strength in the legs. Two patients presented with another primary symptom on diagnosis: pain in the pelvic region and in the left leg. All patients underwent a least one imaging test (MRI/CT scan). Nine patients had tumors limited to the sacrum or with subsequent spread, with surgery via the posterior route. In 6 cases, an exclusively anterior approach was employed owing to the pre-sacral location of the tumor; 4 cases required both an anterior and posterior approach.

RESULTS

The 6 patients who were asymptomatic at diagnosis continued to have no symptoms after surgery. In 8 patients, symptoms resolved after surgery, and at discharge 4 had pain in the lumbar region or legs, which improved in subsequent consultations. One patient had symptoms consistent with motor and sensory deficit in the right leg deriving from impairment of the external popliteal sciatic nerve. The mean follow-up period was 69 months (6-178 months). Histologically, 17 cases were classified as schwannomas, one case was classified as neurofibroma, and one case was classified as neurofibrosarcoma, which received radiotherapy. Three patients with benign histologies had further surgery for local recurrences.

CONCLUSIONS

When selecting the approach, the large size that these tumors can reach, their relationship with structures, and their anterior or posterior spread should be taken in to account. Resecting the tumor mass as much as possible provides greater benefit to the patient, as this decreases the odds of tumor recurrence without increasing intraoperative and postoperative complications when multidisciplinary teams are also used.

Safe laparoscopic resection of a giant schwannoma in the retroperitoneum using a fluorescent ureteral stent: a case report

Schwannomas that occur in the retroperitoneal cavity are rare. We herein report a patient who underwent safe laparoscopic resection by using a preoperative 3D computed tomography (CT) image and a fluorescent ureteral stent during the surgery.

A 47-year-old man presented with left lower abdominal pain. CT showed a 10-cm continuous retroperitoneal tumor originating at the third lumbar nerve in the lower left abdomen. Schwannoma was suspected. We underwent laparoscopic resection of the tumor guided by 3D images obtained preoperatively. A fluorescent ureteral stent was implanted during the surgery to improve visibility and protect the left ureter. The resection was completed without injury of other organs and vessels. The patient was discharged on postoperative Day 5.

By performing a preoperative simulation using 3D CT images, we could anticipate the anatomical findings and easily identify them intraoperatively. In addition, the fluorescent ureteral stent provided visual support, thereby contributing to safe surgery.

Robotic-assisted excision of a juxta renal retroperitoneal schwannoma

Retroperitoneal schwannoma is a rare benign tumor of the peripheral nerve Schwann sheath. We, herein, report the case of a 74-year-old woman who presented with vague abdominal pain. Computed tomography imaging revealed a retroperitoneal mass that is medial to the right kidney. The patient underwent robotic excision of the tumor with the pathology revealing schwannoma. We report this case due to the scarcity of this disease entity, especially at this location and to emphasize the indication and value of robotic technology in different pathological processes retroperitoneally.

Adrenal schwannoma: A case report of an unusual incidentaloma

Introduction and importance

Adrenal schwannomas are extremely rare tumors often misdiagnosed. The patients are usually asymptomatic while some present with non-specific abdominal pain. Only a few cases are reported to date.

Case presentation

We here present a case of a 55-year-old Nepalese man presented with nonspecific abdominal pain at our Outpatient Department (OPD) found to have mass on ultrasonography of abdomen. On further investigation with Contrast Enhanced Computerized Tomography (CECT) of the abdomen and pelvis, a well-defined heterogeneous adrenal mass of size (7.8 ∗ 8.3 ∗ 6) cm with foci of calcification was seen in the left retroperitoneum. The intraoperative finding of adrenal mass and histopathology of resected mass was suggestive of schwannoma arising from the adrenal gland which was further confirmed by immunohistochemistry.

Clinical discussion

Adrenal schwannoma can mimic tumors like pheochromocytoma, adrenal adenoma, cortical carcinoma, neuroblastoma, and other masses. Only 1–3% of schwannomas are retroperitoneal. Radiological findings of this tumor are non-suggestive. The histological section shows spindle cells with Antoni A and Antoni B regions while positive staining of S-100 protein in Immunohistochemistry.

Conclusion

The diagnosis of adrenal schwannoma in the retroperitoneum is often challenging. The treatment of choice is surgical resection with a good prognosis.

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Adrenal schwannomas are extremely rare tumors.

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These tumors are mostly found incidentally and often asymptomatic.

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Complete surgical resection of the tumor is a must for good prognosis.

Surgery of neurogenic tumors of the sacrum

OBJECTIVES

Our objective is to share our experience in neurogenic tumors of the sacral area, an uncommon disease, and assess approaches, intraoperative techniques, complications and clinical course of patients in a case series.

METHODS

We conducted a retrospective analysis of 19 cases of patients with neurogenic tumors in the sacral area who were diagnosed and underwent surgery at our center. Of them, 8 were male and 11 were female. They had a mean age at diagnosis of 51 years (with an age range of 25-78 years). Six patients were asymptomatic and were diagnosed incidentally, while the majority (11 patients) presented with lumbar pain accompanied by other symptoms: pain radiating to the legs, pelvic pain, sensory alterations and loss of strength in the legs. Two patients presented with another primary symptom on diagnosis: pain in the pelvic region and in the left leg. All patients underwent a least one imaging test (MRI/CT scan). Nine patients had tumors limited to the sacrum or with subsequent spread, with surgery via the posterior route. In 6 cases, an exclusively anterior approach was employed owing to the pre-sacral location of the tumor; 4 cases required both an anterior and posterior approach.

RESULTS

The 6 patients who were asymptomatic at diagnosis continued to have no symptoms after surgery. In 8 patients, symptoms resolved after surgery, and at discharge 4 had pain in the lumbar region or legs, which improved in subsequent consultations. One patient had symptoms consistent with motor and sensory deficit in the right leg deriving from impairment of the external popliteal sciatic nerve. The mean follow-up period was 69 months (6-178 months). Histologically, 17 cases were classified as schwannomas, one case was classified as neurofibroma, and one case was classified as neurofibrosarcoma, which received radiotherapy. Three patients with benign histologies had further surgery for local recurrences.

CONCLUSIONS

When selecting the approach, the large size that these tumors can reach, their relationship with structures, and their anterior or posterior spread should be taken in to account. Resecting the tumor mass as much as possible provides greater benefit to the patient, as this decreases the odds of tumor recurrence without increasing intraoperative and postoperative complications when multidisciplinary teams are also used.

Laparoscopic resection of primary retroperitoneal schwannoma: A case report

BACKGROUND

Schwannomas are rare, often benign, tumors deriving from Schwann cells that have low incidence in the retroperitoneal region (0.5% to 5%). Their diagnosis is hardly confirmed at early stage due to lack of specific features in signs, symptoms and imaging tests. Thus, it is necessary performing guided punch biopsy in order to identify it. Tumor removal is the treatment of choice due to its low sensitivity to radiation and chemotherapy.

CASE SUMMARY

Forty-seven years old female patient who was hospitalized for elective orthopedic procedure, without complications, evolved with severe pain in the lower limbs, thigh and gluteal region associated with neurogenic claudication. Persistent pain required magnetic resonance imaging (MRI) of the lumbar spine, which showed epidural collection with dural compression and massive heterogeneous perihepatic nodular lesion. The surgical team opted for draining the collection, as well as requested an MRI of the abdomen and pelvis, whose analysis showed expansive lesion in the retroperitoneum, in close contact with the inferior vena cava and with the right renal vein. A guided puncture was performed for diagnostic clarification, which showed immunohistochemical profile compatible with schwannoma. The selected treatment comprised retroperitoneum tumor resection in association with laparoscopic cholecystectomy. The patient was discharged and remained stable after 4-mo follow-up; she remains under follow-up to check the need of cancer investigations.

CONCLUSION

Schwannoma features requires surgical treatment based on laparoscopic resection, which often presents low relapse rates and optimistic prognosis.

Giant Sacral Schwannoma Causing Bilateral Hydronephrosis: Case Report and Review of the Literature

BACKGROUND

Giant sacral schwannomas are very rare, and less than 1%-5% of spinal schwannomas are found in the sacral region. These frequently grow to considerable size because of permissive anatomic location and benign, slow growth of tumor. They can be unnoticed before reaching a huge size.

CASE DESCRIPTION

We report a rare case of a giant sacral schwannoma in a 46-year-old man. The patient presented with difficulty in passing urine, episodic constipation, and swelling of the right lower extremity for 6 months. Magnetic resonance imaging revealed 160 x 110 x 110 mm encapsulated heterogenous solid mass originated from left S1 spinal nerve extending into the pelvis and abdomen. Sigmoid colon and rectum were displaced to the right side, and bladder was displaced anteriorly. Left side of the S1 and S2 vertebral bodies, left S1 and S2 neural foramen were also eroded. It also compressed ureters causing bilateral hydronephrosis. The patient underwent a 2-stage procedure in which complete resection was achieved.

CONCLUSIONS

We report the second case of a completely resected giant sacral schwannoma with bilateral hydronephrosis in the literature. Performing a 2-stage procedure is important in giant sacral schwannomas. Morbidity can be minimized, and extent of resection can be maximized with the help of combined anterior/posterior approach.

Retroperitoneal schwannoma sandwiched between abdominal aorta and inferior vena cava. A case report

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Retroperitoneal schwannomas in the abdominal cavity are rare and pose difficulty in preoperative diagnosis and management.

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Imaging modalities are usually not sufficient to conclude a diagnosis.

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EUS-FNA is useful to confirm preoperative diagnosis.

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In EUS-FNA, diagnosis can be accurate if the tumor size is small and tumor is devoid of intratumoral degenerations.

Introduction

Schwannomas are tumors that originate from the Schwann cells present in the nerve sheath of peripheral nerves. They are commonly seen in cephalocervical areas. Schwannomas in the abdominal cavity are rare. Here, we discuss a case of retroperitoneal schwannoma lying dorsal to pancreas with critical relations to surrounding vessels.

Presentation of case

A 74 years old asymptomatic male was found with elevated amylase level on his routine blood examination. MR imaging revealed retroperitoneal mass of size 21*18*24 mm. EUS-FNA confirmed retroperitoneal schwannoma. The patient had co-morbid renal disease and was on hemodialysis. During the latest follow up, the tumor was 41*37*41 mm in size located dorsal to the confluence of right renal vein and inferior vena cava. The tumor was in contact with inferior vena cava, horizontal part of duodenum, right renal artery, right kidney, and adrenal gland. The patient underwent laparotomy and the tumor was extract with intact capsule. There were no post-operative complications.

Discussion

Pre-operative diagnosis in retroperitoneal schwannomas is challenging because imaging features are usually non-specific, and biopsy is the only diagnostic technique. EUS-FNA, which has low diagnostic accuracy, is useful in pre-operative diagnosis of small tumors devoid of intra-tumoral degeneration.

Conclusion

Retroperitoneal schwannoma is a rare entity. Preoperative diagnosis and curative resection are technically difficult. Care should be given during preoperative investigations and surgical resection of the tumor. EUS-FNA can be a useful diagnostic tool.

Malignant peripheral nerve sheath tumor of the sciatic nerve presenting with leg pain in the setting of lumbar scoliosis and spinal stenosis

STUDY DESIGN

Case report.

OBJECTIVE

We present a case of malignant peripheral nerve sheath tumor (MPNST) presenting as neuropathic pain in the setting of lumbar scoliosis and spinal stenosis. Most peripheral nerve sheath tumors are benign, and malignant cases are more commonly associated with neurofibromatosis type 1 or prior radiation exposure. MPNST is a rare tumor with a poor prognosis. We report a case of MPNST that presented as neuropathic pain following lumbar decompression and fusion surgery.

METHODS

A 60-year-old woman presented for management of lumbar scoliosis, stenosis, and left leg pain. After lumbar decompression and fusion surgery, the patient was readmitted to the hospital after falling 10 weeks post-op. She reported gradual recurrence of leg pain. Left foot drop was noted on exam. Imaging studies showed no spinal changes postoperatively or residual stenosis. Obesity limited electrodiagnostic studies. Hip MRI revealed a lobular soft tissue mass in the left sciatic notch. Surgical resection and pathology provided the diagnosis of MPNST. The patient declined wide resection and other interventions after seeking a second opinion. Palliative pain management was implemented.

RESULTS

The patient expired 15 months after her index spinal surgery.

CONCLUSIONS

MPNST is an extremely rare tumor that can present with symptoms similar to radiculitis. Clinical signs and symptoms of MPNST are vague and nonspecific due to compression of surrounding structures. Surgical wide resection is the first line of treatment for MPNST with chemotherapy and radiotherapy as adjuvant treatments. MPNST has a poor prognosis with reported 5-year survival ranging from 16 to 54%. This case demonstrates the need to pursue additional workup when diagnostic imaging and objective findings do not satisfactorily explain the clinical presentation.

LEVEL OF EVIDENCE

IV.

Schwannoma Misdiagnosed as Adrenal Adenoma: A Case Report and Review of the Literature

Schwannoma is a benign neurogenic tumor originating from the neural sheath of Schwann cells. It is an extremely rare cause of adrenal adenoma which is very difficult to diagnose preoperatively. We report the case of a right adrenal schwannoma discovered incidentally in a 62-year-old woman during evaluation of right flank pain. The biochemical and hormonal evaluations were unremarkable. Radiological examination revealed a 4.8 cm lesion keeping with right adrenal adenoma. Surgical intervention was done due to the large size of the tumor, and laparoscopic right adrenalectomy was performed. The postoperative course was uneventful. Histological examination established the diagnosis of schwannoma, which was further confirmed by immunohistochemical staining. In conclusion, adrenal schwannoma is extremely rare and can be misdiagnosed as nonsecreting adrenal adenoma. Complete surgical excision is the treatment of choice which is associated with favorable outcome and also helps in clarifying its histopathological nature.

Robot-Assisted Laparoscopic Excision of Complicated Retroperitoneal Tumors with Four Arms Via Retroperitoneal Way: A Unique Minimal-Invasive Approach

Background: Surgical management of complicated retroperitoneal mass is one of the most challenging urologic oncologic surgeries. This study aims to describe our technique and experience in dealing with retroperitoneal mass. Methods: Three patients with complicated retroperitoneal mass were treated with robot-assisted surgery with four arms through retroperitoneal approach. Surgical Procedure: Our standardized anatomic-based "kidney safe first, then mass resection" technique for robot-assisted complicated retroperitoneal mass resection focused on minimizing the chance of renal pedicle injury. Baseline demographics, pathology data, and latest follow-up outcome were obtained. Results: In this retrospectively reviewed case series, all 3 patients were successfully treated with robot-assisted surgery with four arms during retroperitoneal space. One patient received paravertebral mass resection 2 weeks after the robotic surgery. Mean data included operative time of 175 minutes, estimated blood loss was 133 mL, and hospital stay was 4 days. No complications occurred. Conclusions: Robot-assist surgery for complicated retroperitoneal mass with four arms is a safe and feasible way. Patient Summary: Mini-invasive treatment for retroperitoneal mass with robotic four arms through retroperitoneal approach is a feasible way. The approach reduces interruption of intracorporeal structure and organs. And patients could benefit from the retroperitoneal approach with a quicker recovery.

Pelvic Schwannoma: In light of a case report

A 41-year-old man with abdominal enlargement, as a result of large retroperitoneal Schwannoma, was reported to our center. It was seen to have caused the displacement of the colon and was attached to the presacral region of the spine. Following the diagnosis, successful resection of Schwannoma was achieved.

Esophageal schwannoma: Case report and epidemiological, clinical, surgical and immunopathological analysis

INTRODUCTION

Schwannoma is a tumor of the peripheral nervous system originated in the Schwann cells of the neural sheath.

PRESENTATION OF CASE

A 43-years-old male complained of odynophagia, dysphagia and hemoptysis. The upper gastrointestinal endoscopy showed a smooth elevated lesion, 20 cm from the incisor teeth, occupying the entire lumen of the esophagus. The chest computed tomography (CT) scan showed a lesion of 7 cm and superior mediastinal, lower paraesophageal and cardiac enlarged lymph nodes. A posterolateral thoracotomy was performed with total esophagectomy without intraoperative complications. The anatomopathological analysis revealed fusocellular mesenchymal neoplasia of low malignancy potential. The immunohistochemical study showed positivity for S-100 protein and KI67 antibodies and absence of staining for CD117, CD34, ALK protein, SMA and Desmin. Thus, the morphological and immunohistochemical findings pointed to the diagnosis of esophageal Schwannoma.

DISCUSSION

Although rare and indolent, Schwannoma occurs in the peripheral nervous system, being uncommon in the esophagus.

CONCLUSION

The immunohistochemical study is essential for the diagnosis, which is based on the positivity for S-100 protein and absence of staining for CD34 and CD117.

Retroperitoneal malignant schwannoma in a child

Retroperitoneal malignant schwannomas are extremely rare. Only a few cases have been reported, only one of which occurred in a child. We herein report a case of retroperitoneal malignant schwannoma in a 2-year-old boy who presented with a painless mass in the right lumbar region. The mass had gradually enlarged during a 1-year period, and it was about the size of the patient's fist at the time of consultation. Whole-abdomen computed tomography revealed a space-occupying lesion in the retroperitoneum infiltrating from the L1 to L4 spinal canal. A preoperative diagnosis of a retroperitoneal tumor was made, and complete tumorectomy was performed. Postoperative pathological examination showed a malignant schwannoma. The tumor recurred 1 month after the first operation, and a second complete excision was carried out; the postoperative pathologic examination findings were similar to the previous findings. The patient recovered well and continued to undergo close follow-up.

Surgical management of retroperitoneal schwannoma complicated with severe hydronephrosis: A case report

RATIONALE

Schwannomas are usually benign tumors arising from well-differentiated schwann cells, which rarely occur in the retroperitoneal space. The lack of specific signs and radiologic imaging characteristics makes preoperative diagnosis rather difficult. Most retroperitoneal schwannomas are benign and the primary treatment choice for retroperitoneal schwannomas is surgical excision, however, the involvement of the urinary system is scarcely reported.

PATIENT CONCERNS

A 34-year-old woman presented with progressive left abdominal pain and rebound abdominal mass at the left lower quadrant for 1 month. Radiological imaging suggested capsulated solid mass with cystic and necrotic areas in the retroperitoneum accompanied by severe left kidney hydronephrosis and preoperative biopsy result was inconclusive.

DIAGNOSES

We believe this is a rare case of retroperitoneal schwannoma complicated with severe hydronephrosis.

INTERVENTIONS

After preparation, the patient underwent laparoscopy exploration and converted to open surgical exploration. The patient accepted complete surgical excision of the retroperitoneal tumor and left kidney. Postoperative pathology diagnosis of the mass was proven to be benign retroperitoneal schwannoma.

OUTCOMES

Postoperative course of the patient was uneventful and the left abdominal pain was greatly improved. After 12-month follow up, no evidence of recurrence or any other complication including renal failure was observed.

LESSONS

Preoperative imaging and preoperative ultrasound-guided biopsy are helpful to make accurate diagnosis. The final diagnosis is based on postoperative histological and immunohistochemical findings. The primary treatment option is complete surgical resection of the retroperitoneal schwannoma and the involved upper urinary system when severe hydronephrosis occured. Local recurrence and overall survival are closely correlated with negative resection margins and pathology types.

Clinical features and surgical treatment of sacral schwannomas

BACKGROUND

Sacral schwannoma is relatively rare and both the early diagnosis and appropriate treatment of sacral schwannomas are equally very challenging.

METHODS

11 sacral schwannoma cases operated at the Second Affiliated Hospital, School of Medicine, Zhejiang University, from 2012 to 2016, were investigated retrospectively and 10 were followed up. All patients were assessed with X-ray, CT and MRI, and underwent an intralesional excision.

RESULTS

One patient was male, nine were female and the average age was 48 (ranging between 31 and 63). Three patients suffered from back and leg pain, and seven had no obvious symptoms. The average blood loss during surgery was 980ml (ranging between 100 and 2,000ml). Six patients underwent preoperative biopsy. The surgeries were performed via the combination of an anterior and posterior approach in two patients, a posterior approach in seven patients, and an anterior approach in one patient. Residual tumors were not detected in all patients after surgery. Unfortunately, the postoperative complications occurred in three patients, namely bowel and bladder dysfunction (two patients) and cerebrospinal fluid leakage with secondary intracranial infection (one patient). The average follow-up was 22.7 months (8-44 months). All patients were relieved from preoperative symptoms after the last follow-up.

CONCLUSIONS

The typical findings of our cases in MRI were a well-circumscribed lesion with a heterogenous signal intensity on T2-weighted image, which may be helpful for preoperative decision-making. Intralesional excision can be successfully performed using single anterior or single posterior or both, and is an important procedure in the treatment of sacral schwannomas.

Benign diaphragmatic neurilemmoma mimicking a left adrenal cyst

Neurilemmomas are benign, slow growing, encapsulated nerve sheath tumor. These tumors arise from the schwann cells of neural crest. Neurilemmomas can manifest in various form according to site, extent and severity of involvement of organ. Diaphragmatic neurilemmomas are very unusual and even difficult to diagnose on preoperative imaging. We will report a case of 39 year old male, who presented with complaints of occasional left flank pain for one year and subsequently investigated, which showed left adrenal cyst with haemorrhagic fluid content. On the contrary, when surgical exploration of the lesion was done, it showed a cyst within the diaphragm, completely separated from left kidney and left adrenal with haemorrhagic content in situ. Histopathological examination of the lesion showed it to be a benign neurilemmoma with cystic degeneration. Post opearatively patient did well. We believe that this is the first case report, which is addressing such kind of initial manifestation of diaphragmatic neurilemmomas.

Non-Syndromic Spinal Schwannomas: A Novel Classification

Schwannomas are the most frequent primary tumors of the spine with an incidence of 0.3-0.5/100,000 person per year. Current treatment for non-syndromic spinal schwannomas is total resection of the tumor with preservation of neurovascular structures. This study aims to report neurologic and radiologic outcome following treatment of non-syndromic spinal schwannomas along with a novel tumor classification used in our clinic. A retrospective case series was carried out with a patient sample of 82 male and female patients with non-syndromic spinal schwannomas. All patient data were retrospectively collected from the hospital records. As a routine procedure, after admittance and primary evaluation, patients' tumors were classified using CT or MRI in accordance with our proposed classification method, which employs a dual designation method with tree groups (A, B, and C) for tumor volume and four types (I, II, III, and IV) for tumor localization. Subsequent resection surgery was followed by neurological assessments and follow up at 45th, 180th, and 360th postoperative day. Along with Karnofsky performance status scale, pain, sensory deficits, and motor weakness were scored to assess neurologic recovery. Our finding indicates that patients with different tumor types significantly differ in their neurological scores and show consistent but differential neurological recovery at early and late time points postsurgery. Complications during and postsurgery were minimal, occurring only in two patients. Our findings further reinforce the established safety of total resection operations and indicate that our proposed classification is a simple, effective tool that has proven helpful in preoperative planning and avoiding unnecessary surgical approaches.

Schwannoma of the psoas: An unusual cause of abdominal pain

Schwannomas are usually benign tumours arising from Schwann cells of peripheral nerve sheath. Retroperitoneal location is extremely rare compromising 0.5-5% of all schwannomas, except in patients having von Recklinghausen's disease, in whom retroperitoneal location is more frequent and malignant cases are known to occur. Complete surgical excision with negative margins is the definitive treatment on which the diagnosis is usually made due to nonspecific radiologic appearance. In this article we would like to present an unusual cause of recurrent, abdominal pain in an eighty-six-year-old male.

Primary retroperitoneal masses: what is the differential diagnosis?

Primary retroperitoneal masses include a diverse, and often rare, group of neoplastic and non-neoplastic entities that arise within the retroperitoneum but do not originate from any retroperitoneal organ. Their overlapping appearances on cross-sectional imaging may pose a diagnostic challenge to the radiologist; familiarity with characteristic imaging features, together with relevant clinical information, helps to narrow the differential diagnosis. In this article, a systematic approach to identifying and classifying primary retroperitoneal masses is described. The normal anatomy of the retroperitoneum is reviewed with an emphasis on fascial planes, retroperitoneal compartments, and their contents using cross-sectional imaging. Specific radiologic signs to accurately identify an intra-abdominal mass as primary retroperitoneal are presented, first by confirming the location as retroperitoneal and secondly by excluding an organ of origin. A differential diagnosis based on a predominantly solid or cystic appearance, including neoplastic and non-neoplastic entities, is elaborated. Finally, key diagnostic clues based on characteristic imaging findings are described, which help to narrow the differential diagnosis. This article provides a comprehensive overview of the cross-sectional imaging features of primary retroperitoneal masses, including normal retroperitoneal anatomy, radiologic signs of retroperitoneal masses and the differential diagnosis of solid and cystic, neoplastic and non-neoplastic retroperitoneal masses, with a view to assist the radiologist in narrowing the differential diagnosis.

Laparoscopic Excision of Retroperitoneal Schwannoma

Schwannomas are tumours that arise from the myelin sheath of the nerves. A very unusual location for schwannoma is the retro peritoneal areas (less than 2%). We present herewith a patient who had a 4x5cm Schwannoma arising from the nerve root of L2 on the right side, which presented as a lump in the psoas major muscle. This was treated by total laparoscopic excision after splitting open the psoas major. In the published english medical literature we could find only 16 cases of laparoscopic resection of retroperitoneal schwannoma and we believe ours to be the first case that was done through a psoas muscle split technique. Technical and histopathological details are discussed elaborately in this article.

Giant cystic sacral schwannoma mimicking tarlov cyst: a case report

PURPOSE

To present a rare case of a giant schwannoma of the sacrum mimicking a Tarlov cyst.

METHODS

A 58-year-old woman had a 1-year history of low back pain. MRI revealed a large cystic mass in the sacral canal with bony erosion. Radiological diagnosis of Tarlov cyst was made.

RESULTS

The patient underwent surgical treatment for the lesion, which revealed a solid mass. Histopathological examination of the tumor confirmed the diagnosis of schwannoma. The postoperative course was uneventful and the patient has had significant improvement in her pain 1 month postoperatively.

CONCLUSION

Giant cystic schwannoma of the sacrum is a very rare diagnosis overlooked by practitioners for more common cystic etiologies, but its treatment is significantly different. Care should be taken to include this diagnosis in a differential for a cystic sacral mass.

Adrenal Schwannomas: Rare Tumor of the Retroperitoneum

Schwannoma is a benign neurogenic tumor originating from Schwann cells. These produce the myelin sheath that covers peripheral nerves that are often affected. This latter localization is extremely rare, and only a few case reports can be found in the medical literature. Studies have shown that approximately 0.5% to 5% of schwannomas are retroperitoneal, constituting 0.2% of adrenal incidental tumors. These usually present as incidental findings, nonsecreting adrenal masses in asymptomatic patients. Diagnosis of a schwannoma is based on detection of spindle cells with Antoni A and Antoni B regions in histological sections and positive staining for S-100 protein by immunohistochemical analysis. We report a case of an incidentally identified during an abdominal ultrasound examination with schwannoma localized in the left adrenal gland.

Taking it to the next level: lumbar radiculopathy from thoracic nerve schwannoma

Compression or irritation of the sciatic nerve and its branches, the common fibular and tibial nerves, causes sciatica which is a common syndrome characterized most often by radiating pain from the lower back down the legs and also manifesting as sensory and motor deficits. Sciatica is a common presentation of lumbosacral disc prolapse and degenerative disease of the lumbar spine in ambulatory settings. Schwannomas rarely cause sciatica; hence, it is seldom considered in evaluation of a patient with radiculopathy. Our patient presented with lumbar radiculopathy, mild degenerative changes on lumbar magnetic resonance imaging (MRI) scan, and failed conservative treatment. Myelopathy was confirmed with electromyogram (EMG). Thoracolumbar spine MRI revealed the schwannoma in the thoracic region. He recovered neurologic function after tumor excision. This case highlights the diagnostic challenge that may arise in evaluating a patient with lumbar radiculopathy, negative lumbosacral spine imaging, and failure of conservative therapy.

S, M. R. Benign paravertebral ancient neurilemmoma in a young adult: a rare occurrence

Neurilemmoma is a benign neurogenic tumour arising from Schwann cells of the peripheral nerve sheath, which is commonly seen in women in the 5th decade. It rarely arises in the retroperitoneum, being more common in the head and neck region and extremities. Ancient variety of schwannoma is a long-standing tumour, is seen in the middle age and elderly age groups, and is associated with secondary degenerative changes. Herein, we report a case of benign retroperitoneal paravertebral ancient neurilemmoma occurring in a young male adult.

Juxta-adrenal Ancient Schwannoma: A Rare Retroperitoneal Tumor

Retroperitoneal schwannoma is a rare tumor that is often misdiagnosed as malignancy due to a concerning appearance on cross-sectional imaging. Pathology and immunohistochemistry form the gold standard for diagnosis; as such, local excision is the treatment of choice for this disease. We present two cases of juxta-adrenal ancient schwannoma that were treated with adrenalectomy and discuss the current literature regarding this entity.

Retroperitoneal schwannoma: an atypical presentation

Schwannoma is a rare tumour arising from Schwann cells in myelinated neural sheath of the nerves. They can arise in various places like head, neck, extremities, adrenal, retro peritoneum, psoas muscle. We here present a case of 33-year-old male who came with features of acute pancreatitis, with incidentally detected mass in presacral region on ultrasonography. Investigations like CECT and MRI were suggestive of neurofibroma, radical excision of the mass was done which showed solitary encapsulated tumour and cut sections showed areas of necrosis, and histopathologically it was proven as schwannoma. Most of the schwannoma's are benign, but rarely malignant transformation can occur. It can be associated with von Recklinghausen disease. Benign tumours have excellent prognosis, malignant tumours can present at later date with metastasis after excision also. Radiology plays a key role in diagnosis and follows up. Treatment is radical excision of tumour; recurrence is most common and has to be carefully followed up.

Cystic giant sacral schwannoma mimicking aneurysmal bone cyst : a case report and review of literatures

To present a rare case of a cystic giant schwannoma of the sacrum mimicking aneurysmal bone cyst (ABC). A 54-year-old man visited our institute complaining left leg weakness and sensory change for several years. Magnetic resonance imaging revealed a large multilocular cystic mass with canal invasion and bone erosion confined to left S1 body. The lesion showed multiple septal enhancement without definite solid component. Initially the tumor was considered as ABC. The patient underwent grossly-total tumor resection with lumbosacral reconstruction via posterior approach. The tumor was proved to be a cystic schwannoma. The postoperative course was uneventful and the patient was relieved from preoperative symptoms. We present a rare case of pure cystic giant schwannoma confined to sacrum mimicking ABC. The surgical treatment is challenging due to the complex anatomy of the sacrum. Schwannoma should be considered in the differential diagnosis of osteolytic sacral cysts.

Laparoscopic resection of an adrenal schwannoma

BACKGROUND AND OBJECTIVES

Schwannomas are tumors originating from Schwann cells of the peripheral nerve sheath (neurilemma) of the neuroectoderm. Rarely, schwannomas can arise from the retroperitoneum and adrenal medulla. We describe a case of a 71-y-old woman who presented with an incidentally discovered adrenal tumor.

METHODS

Ultrasound and computed tomography scans revealed a lesion with solid and cystic areas originating from the left adrenal gland. The patient underwent complete laparoscopic resection of the tumor and the left adrenal gland.

RESULTS

Histopathological examination and immunohistochemical staining of the excised specimen revealed a benign schwannoma measuring 5.5×5 3.7 cm. To our knowledge, few other cases of laparoscopic resection of adrenal schwannomas have been reported.

CONCLUSION

Because preoperative diagnosis of adrenal tumors is inconclusive, complete laparoscopic excision allows for definitive diagnosis with histological evaluation and represents the treatment of choice.

Simultaneous Right Retroperitoneal Schwannoma and Left Renal Hydatid Cyst

Retroperitoneal schwannomas are quite rare tumors. Isolated renal hydatid cyst is also rare, and it forms 2–4% of hydatid disease. Because of their infrequent occurrence, nonspecific signs and symptoms, and lack of distinguishing radiologic features, we report herein a case of right retroperitoneal mass in a 26-year-old woman which was found to be benign schwannoma following a percutaneous core needle biopsy and a large cortical cyst in the lower pole of the left kidney which was diagnosed as isolated renal hydatid cyst following exploration.

Retroperitoneal cystic schwannoma: A case report with review of literature

The occurrence of retroperitoneal schwannoma is uncommon and its presence may only be expressed by insidious onset of nonspecific symptoms such as vague abdominal pain. Imaging modalities like computed tomography and magnetic resonance imaging may demonstrate the tumor, but due to heterogeneity and degeneration in some tumors, it may mimic malignancy. So, fine needle aspiration cytology followed by tissue sampling through needle biopsies may be essential to confirm the diagnosis prior to the surgery. This case is reported for its rare clinical presentation, having duration of more than 40 years with cystic degenerative changes.

Retroperitoneal schwannoma: a rare case

Introduction. Schwannomas are quiet rare in the retroperitoneal region. Here, we describe an incidentally detected retroperitoneal schwannoma in the abdominal computerized tomography (CT) of a patient with acute appendicitis. Case Presentation. A 38-year-old woman was admitted to the emergency service with the complaints of progressive abdominal pain and nausea for the last 24 hours. Abdominal examination was compatible with acute abdomen. Acute appendicitis was diagnosed by CT. During CT evaluation, a round shaped soft-tissue mass at the retroperitoneal area inferior to the right kidney was detected, The mass was resected and histology revealed schwannoma. Conclusion. Rare tumoral lesions with benign course such as schwannoma can be detected incidentally.

Atypical presentations of retroperitoneal giant schwannomas

Schwannomas are usually benign rare tumors that originating from Schwann cells of peripheral nerve sheaths. Presentation is generally varied and changed in a non-specific range from abdominal mass, flank pain to incidental findings. Herein we report 2 cases of retroperitoneal giant schwannomas with different clinical presentations, of whom one presented with vague abdominal pain, palpable abdominal mass for 4 years, swelling and bilateral hydronephrosis that caused by giant abdominal mass; the other one presented with right flank pain, rectal hemorrhage and lower extremities edema. Two patients were treated by complete surgical excision of masses. The histological and immunohistochemical diagnosis was reported as benign schwannoma. Both of patients are doing well and had no recurrence in 9 years and 28 months follow-up, respectively.