Multiple retroperitoneal schwannomas: case report and review of the literature

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.

Sacrococcygeal neurofibroma: rare cause for chronic pelvic pain

Pelvic pain is a common gynecologic complaint. Retroperitoneal pelvic tumors are rarely a cause of pelvic pain. Neurofibroma is an uncommon pelvic retroperitoneal tumor, and only 17 cases are reported to date. A 38-year-old woman with chronic pelvic pain had a soft fixed mass that was the size of an orange in the right posterolateral fornix, with a normal uterus on pelvic examination, and a mass of 6.3 × 5.2 cm with mixed echotexture on the right side separate from both ovaries on transvaginal ultrasonography. A provisional diagnosis of retroperitoneal mass probably a retroperitoneal teratoma was made. Laparoscopy was performed; an ill-defined retroperitoneal soft tissue mass of about 6 cm was seen on the right pararectal and presacral area, displacing the rectum toward the left side. The mass was soft and jellylike without a cyst wall. Histopathologic study and immunohistochemistry results were consistent with neurofibroma of the sacrococcygeal regions. To our knowledge this is the third case of sacrococcygeal neurofibroma treated by complete laparoscopic excision. Gynecologists should keep sacrococcygeal neurofibroma as a differential diagnosis of pelvic pain with atypical location of a pelvic mass. A high index of suspicion and an appropriate imaging technique are needed for accurate diagnosis. Laparoscopy seems to be a safe and effective method of managing retroperitoneal presacral neurofibromas.

Multiple retroperitoneal schwannomas mimicking adrenal tumors

Schwannomas are benign tumors mostly arising from the head and neck. Retroperitoneal schwannomas are rare. Here we report the case of a 68-year-old woman with multiple retroperitoneal schwannomas. An abdominal computed tomography (CT) scan showed 1 non-enhancing mass with a low-density area, 4.6 cm in diameter, in the left adrenal region and another non-enhancing mass with a low-density area, 2.9 cm in diameter, in the para-aortic region. The patient had regularly undergone CT scans for malignant tumor screening in maintenance dialysis patients. Retrospectively, the 2 tumors had existed in the same regions in previous CT scans and had gradually increased in size. The tumors were completely resected. Pathological diagnosis of both tumors was schwannoma. When a CT scan shows a slowly growing retroperitoneal tumor with a low-density area, schwannoma should be considered. If the tumor increases in size, complete resection should be performed for pathological diagnosis.

Recurrent retroperitoneal Schwannomas displaying different differentiation from primary tumor: case report and literature review

Background

Retroperitoneal Schwannomas are uncommonly found in the retroperitoneum and few of them show malignant transformation and invasion. Local recurrence are common in malignant Schwannomas with very few reports of tumor distinct differentiation at recurrences.

Case presentation

We report here a rare case of retroperitoneal schwannoma with multiple origins from retroperitoneum and pelvic wall. Pathological examination confirmed the case as a schwannoma with malignant transformation. Radical dissection of the tumors along with the sacrifice of adjacent sigmoid colon and left kidney failed to provide a cure for this patient. Due to tumor recurrence, a second and a third surgery of radical excision were performed 6 months and 17 months later after the first surgery, respectively. Histopathologic analysis identified that the recurrent tumors were different from the original schwannoma because of their smooth muscle-like differentiation.

Conclusion

Malignant schwannomas are uncommon sarcomas with a high incidence of local recurrence. Distinct immunohistochemical staining results of the tumors at recurrence indicate their potential of smooth-muscle like differentiation. Radical excision of the tumors may provide benefit for their local recurrences.

Intramuscular schwannoma arising from the psoas muscle presenting with femoral nerve neuropathy

A spherical mass of the right psoas muscle was found incidentally by magnetic resonance health examination in a 43-year-old woman. The patient had complained of numbness in her right leg over the previous six months and neuralgia at the time of computed tomography-guided core biopsy, which was done to establish the diagnosis. To our knowledge, femoral nerve neuropathy caused by an intramuscular schwannoma arising from the psoas muscle has not been previously published.

A case report of a giant presacral cystic schwannoma with sigmoid megacolon

Schwannomas are peripheral nerve sheath tumours with a slow growth rate. Giant sacral schwannoma with anterior cortex erosion and associated intrapelvic extension are uncommon. Though they tend to be large when initially found, most Giant schwannomas are clinically asymptomatic. The tumour appears heterogenous due to long standing degeneration. Herein, we present a case of a large purely cystic presacral schwannoma in a patient with poliomyelitis, which has displaced adjacent organs including urinary bladder and sigmoid colon, with an initial presentation of constipation. The tumour was partially excised and diagnosis was confirmed by histo-pathology and immunohistochemistry.

Benign retroperitoneal schwannoma presenting as colitis: A case report

We report a case of a patient presenting with clinical, radiological and endoscopic features of colitis due to a compressive left para-aortic mass. Total open surgical excision was performed, which resulted in complete resolution of colitis. Histopathology and immunohistochemistry revealed benign retroperitoneal schwannoma. These neural sheath tumors rarely occur in the retroperitoneum. They are usually asymptomatic but as they enlarge they may compress adjacent structures, which leads to a wide spectrum of non-specific symptoms, including lumbar pain, headache, secondary hypertension, abdominal pain and renal colicky pain. CT and MR findings show characteristic features, but none are specific. Schwannoma can be isolated sporadic lesions, or associated with schwannomatosis or neurofibromatosis type II (NF2). Although they vary in biological and clinical behavior, their presence is, in nearly every case, due to alterations or absence of the NF2 gene, which is involved in the growth regulation of Schwann cells. Both conditions were excluded by thorough mutation analysis. Diagnosis is based on histopathological examination and immunohistochemistry. Total excision is therapeutic and has a good prognosis. Schwannomatosis and NF2 should be excluded through clinical diagnostic criteria. Genetic testing of NF2 is probably not justified in the presence of a solitary retroperitoneal schwannoma.

Uncommon adrenal masses: CT and MRI features with histopathologic correlation

Adrenal glands are common sites of diseases. With dramatically increased use of computed tomography (CT) and magnetic resonance (MR) imaging, more and more uncommon adrenal masses have been detected incidentally at abdominal examinations performed for other purposes. In this article, uncommon adrenal masses are classified as cystic masses (endothelial cysts, epithelial cysts, parasitic cysts, and pseudocysts), solid masses (ganglioneuroma, ganglioneuroblastoma, extramedullary plasmacytoma (EMP), neurilemmoma, and lymphoma), fat-containing masses (myelolipoma, teratoma), and infectious masses (tuberculoma), and the imaging features of these uncommon masses are demonstrated. Although most of these lesions do not have specific imaging features, some fat-containing masses and cystic lesions present with characteristic appearances, such as myelolipoma, teratoma, and hydatid. Combination with histopathologic characteristic of these uncommon masses of adrenal gland, radiological features of these lesions on CT and MR imaging can be accurately understood with more confidences. Moreover, CT and MRI are highly accurate in localization of uncommon adrenal masses, and useful to guide surgical treatments.

Analysis of 82 cases of retroperitoneal schwannoma

BACKGROUND

The aim of the study was to improve the diagnosis and treatment of retroperitoneal schwannoma by analysing clinical manifestations and postoperative course of this rare disease.

METHODS

A retrospective analysis of 82 patients with retroperitoneal schwannoma between January 1951 and September 2004 was carried out.

RESULTS

The patients were 38 (46%) men and 44 (54%) women between the ages of 6 months and 70 years. The interval between clinical manifestation and diagnosis ranged from 10 days to 2 years. The main symptoms were abdominal distension (30.5%) and abdominal pain (20.7%). Only in 13 patients (15.9%) a correct preoperative diagnosis was made by either ultrasound-guided biopsy, computed tomography scanning or magnetic resonance imaging. All patients received operative therapy. Sixty patients (73.2%) underwent a total resection; 13 patients (15.9%) subtotal resection, but 9 patients (11.0%) had only an examination and a biopsy. Two patients (2.4%) had multiple schwannomas and two others had a simultaneous malignancy (adenocarcinoma of the ascending colon and squamous-cell carcinoma of the lung, respectively). Most of the retroperitoneal schwannomas were close to the spine. Pathological results showed 81 (98.8%) were benign schwannoma and 1 (1.2%) was a malignant one. The tumour size ranged from 3 to 22 cm. One benign schwannoma recurred 3 years after the operation. The patient with malignant schwannoma died 18 months after the operation because of metastasized disease.

CONCLUSION

Most of the retroperitoneal schwannomas are benign. It is difficult to make an accurate preoperative diagnosis. However, with the preoperative assessment of ultrasound-guided fine-needle aspiration, computed tomography and magnetic resonance imaging, the accuracy of diagnosis could definitely be improved. Treatment depends solely on surgery. Malignant schwannomas are insensitive to chemotherapy and radiation, resulting in poor prognosis.

[Malignant retroperitoneal schwannoma]

We present an uncommon case of retroperitoneal malignant schwannoma diagnosed accidentally. The clinical, diagnostic and therapeutic features are discussed.

[Retroperitoneal neurilemmona]

Schwannoma is an uncommon tumor arising from neural sheath of peripheral nerves. Histological findings showing Antoni A and B zones are the main diagnostic features. We report a new case of a retroperitoneal located one, which is not its most usual place to appear, in a 60 year old male, presenting left flank pain. He received surgical treatment, having a satisfactory evolution.

Résection d’un schwannome rétropéritonéal en sablier par abord combiné

BACKGROUND AND PURPOSE

We report a remarkable case of retroperitoneal schwannoma with significant spinal growth illustrating the effectiveness of a combined surgical approach.

METHODS

A 41-year-old man presented with a long history of back pain and unexplained weight loss. An abdominal mass was found in the right upper quadrant. The CT-scan revealed a partially cystic lesion located in the right psoas muscle. Spinal extension was noticed through the L1-L2 neural foramen. MRI better showed the wide rostro-caudal extension in the spinal canal.

RESULTS

Bilateral L1 and L2 laminectomy was performed to remove the spinal portion of the tumor. It was extradural but attached to the dura. The roots were not infiltrated. The retroperitoneal mass was removed by an anterior transperitoneal approach. The histological examination did not reveal criteria of malignancy.

CONCLUSIONS

Retroperitoneal schwannomas are rare and their preoperative diagnosis remains difficult. In case of significant spinal growth, a combined surgical exposure should be preferred to allow total removal of the lesion and control of the neurological structures.

Retroperitoneal giant schwannomas: report on two cases and review of the literature

The occurrence of massive retroperitoneal schwannomas is extremely rare and their presence may only be expressed by insidious onset of non-specific and misleading symptoms with a predominance of lower back pain. MRI scan as the imaging procedure of choice will demonstrate the tumour location and its relation to the surrounding structures, but due to heterogeneity and degeneration in some tumours, it may mimic malignancy. Hence tissue sampling through needle biopsies are essential to verify the diagnosis prior to surgery. Tumour excision in toto is considered the treatment of choice, but it can be hazardous especially if the tumour is adherent to the presacral venous plexus. Severe bleeding complications due to the damage of venous structures have to be encountered, and establishing lasting haemostasis may pose considerable difficulties. Hence surgery should be attempted with full precautions, and preoperative counseling of the patient. If malignancy can safely be excluded, laparoscopic piecemeal excision should be considered as an alternative treatment as recurrence is unlikely. Definition of the originating nerve might not always be possible and a minor degree of neurological impairment has therefore to be anticipated.

Presacral solitary giant neurofibroma without neurofibromatosis type 1 presenting as pelvic mass--case report

A 35-year-old woman presented with a solitary neurofibroma in an unusual presacral location without neurofibromatosis manifesting as bilateral chronic sciatica for 2 years. She was initially considered as having a giant right ovarian mass, but was referred with a prediagnosis of solitary giant sacral nerve sheath tumor. The initial differential diagnosis was based on neuroimaging. A right-sided J incision with the extraperitoneal approach provided good exposure and handling of the tumor bed. Almost total excision without neurological deficit was possible. The histological diagnosis was neurofibroma. Benign retroperitoneal neural sheath tumors in patients without von Recklinghausen's disease are quite rare. Intrapelvic tumors are often diagnosed at a later stage. Neuroimaging is very helpful to delineate this unusual site and the extent of tumor development, and to determine the appropriate surgical intervention. A clear understanding of retroperitoneal anatomy is essential for safe removal of such tumors. Complete resection is preferred to prevent local recurrence and malignant transformation. Although root section is inevitable, neurological deficit is unlikely.

Detection and enrichment of disseminated renal carcinoma cells from peripheral blood by immunomagnetic cell separation

We have established an immunomagnetic separation procedure for the detection of circulating tumor cells in the peripheral blood based on the magnetic cell sorting (MACS) technique. In previous in vitro experiments, renal-cell carcinoma (RCC) cells were mixed with peripheral blood. In dilutions of 1:200 to 1:107 tumor cells per mononuclear blood cells, an average recovery rate of 84% of tumor cells was determined. In our study, 104 peripheral blood samples from 59 renal carcinoma patients were analyzed. MACS resulted in significant depletion of leukocytes, permitting a search for tumor cells on just 1 slide. Analyzing 8 ml of peripheral blood per patient, 19/59 RCC patients carried disseminated tumor cells (32%) in the range of 1 to 38 cells (median 8). Interestingly, for the cytokeratin-positive (CK+) patient group, we found a correlation between tumor cell number and grading (G2 vs. G3) and an increased number of CK+ patients with advanced tumor stage. MACS appears to be an efficient technique to detect disseminated tumor cells in peripheral blood.

[Benign presacral schwannoma producing obstructive uropathy. Clinical case and review of the literature]

We report a case of a presacral benign schwannoma which causes right hydroureteronephrosis without other clinical findings. After a fine-needle aspiration (FNA) biopsy under computed tomography (CT) guidance, a fusocellular tumour without athypia was demonstrated. With the initial diagnosis of benign schwannoma the patient was operated on, removing the tumour, and with the immunohistochemical examination (reactivity for S-100) this diagnosis was confirmed.

[Retroperitoneal benign schwannoma. Report of a new case]

The schwannoma is a tumor resulting from the Schwann cells of neural shwath, being its retroperitoneal localization quite unusual. This tumor is clinically unspecified and in most of the cases it originates symptoms coming from the compression of the close structures when its localization is retroperitoneal. Its diagnosis is quite often fortuitous being confirmed by anatomopathological study afterwards. The treatment is surgical radical exeresis with subsequent followup. We report a new case of this uncommon retroperitoneal pathology in a female patient showing a nonspecific clinic. Two years after the surgery she remains asymptomatic without any radiological evidence of recidive.

Micrometastatic bone marrow involvement: detection and prognostic significance

The present review focuses on the methodology and clinical significance of new diagnostic approaches to identify individual cancer cells present in bone marrow, both as a frequent site of metastasis formation and an indicator organ for hematogenous tumor cell dissemination. The steadily increasing number of studies on this issue is characterized by considerable methodological variations of important variables, such as the size of the study population, and the reliability of monoclonal antibodies used for tumor cell detection. Emerging data indicate that this disturbing heterogeneity might be overcome by the use of reliable and specific anti-cytokeratin antibodies (for example, A45-B/B3) as, for the time, standard markers for the detection of micrometastatic tumor cells in bone marrow. Prospective clinical studies have shown that immunoassays based on anti-CK antibodies identify patients' subgroups with a poor clinical prognosis with regard to early metastasis manifestation and reduced overall survival in various epithelial tumor entities, including breast, colon, rectum, stomach, esophagus, prostate, renal, bladder, and non-small cell lung cancer. The immunocytochemical assays may be therefore used to improve tumor staging with potential consequences for adjuvant therapy, because disseminated cells appeared to be dormant, non-cycling (for example Ki-67 antigen-negative) cells, suggesting a resistance to cell-cycle dependent therapy, such as chemotherapy. Therefore, cell-cycle independent antibody-based immunotherapy might be an interesting option to complement chemotherapy. Another promising clinical application is monitoring the response of micrometastatic cells to adjuvant therapies, which, at present, can only be assessed retrospectively after an extended period of clinical follow-up. The outlined current strategies for detection and characterization of cancer micrometastasis might help to design and control new therapeutic strategies for secondary prevention of metastatic relapse in patients with operable primary carcinomas.

Diagnosis of minimal residual disease in bone marrow and blood in cancer patients--methods and clinical implications

For some types of cancer the presence of tumour cells in the bone marrow at diagnosis is an independent prognostic factor. Immunocytochemical staining techniques have led to improvements in the ability to detect occult cancer cells in bone marrow. One major limitation of these methods is that the monoclonal antibodies used are only tumour-associated and not tumour-specific. Therefore, some cross reaction with normal cells can occur. Polymerase chain reaction (PCR) has been applied extensively to measure minimal residual disease in bone marrow and blood of lymphomas carrying the t(14;18) translocation and Philadelphia chromosome (PH)-positive chronic myelogenous leukaemia. One major limitation of the PCR method is that not all tumours of interest carry chromosomal translocation. Reverse transcription PCR assays (RT-PCR) that screen for expression of tissue-specific and tumour-associated genes mRNA in bone marrow and blood have been developed. As in the case of immunocytochemistry, not all RT-PCR assays have the specificity required for them to be used safely in the clinic. Therefore, prior to introducing these methods in the clinic, standardized protocols need to be developed and validated.

Schwannoma of the urinary bladder: a case report

The urinary bladder is an extremely rare site for primary schwannomas. They are most often associated with von Recklinghausen disease. This patient was found to have a schwannoma of the bladder in the absence of evidence of von Recklinghausen disease and was successfully treated with a partial cystectomy. This represents only the third such case in the literature of this entity.

Benign retroperitoneal neural sheath tumors in patients without von Recklinghausen's disease

Benign retroperitoneal neural sheath tumors in patients without von Recklinghausen's disease are quite rare and usually presented as isolated case reports. There are two types of benign neural sheath neoplasms: schwannoma and neurofibroma. Confusion exists in the nomenclature of these tumors due to the disagreement upon their cell of origin. In a collective report from two institutions, three cases with benign retroperitoneal neural sheath tumors are presented, and the histological features, diagnostic and therapeutic options are discussed.

Detection of minimal disease in patients with solid tumors

The detection and elimination of minimal systemic disease in patients with solid tumors is one of the main current topics in clinical oncology. The present review focuses, therefore, on new diagnostic approaches to identify minimal disease in peripheral blood, bone marrow, and lymph nodes of patients with epithelial cancer as the major type of solid tumors in Western industrialized countries. These approaches may be used to improve tumor staging and monitoring of adjuvant therapies, as well as to detect tumor cell contamination in autologous stem cell grafts. Most investigators have developed either immunocytochemical assays with monoclonal antibodies to a variety of epithelial-specific cytoskeleton and membrane antigens or molecular methods based on the extensive amplification of a specific (c)DNA sequence by the polymerase-chain reaction (PCR). In immunocytochemical assays, antibodies to cytokeratins can be regarded as the most specific and sensitive probes to detect isolated epithelial tumor cells in bone marrow and blood. Molecular methods are based on the detection of either mutations in oncogenes and tumor suppressor genes (e.g., ki-ras and p53 genes) or the mRNA expression of tissue-specific and tumor-associated genes. mRNA species targeted in these assays encode cytokeratins, prostate-specific antigen, prostate-specific membrane antigen, carcinoembryonic antigen, and polymorphic-epithelial mucin. To introduce the available methods into clinical practice, standardized protocols need to be developed and validated in multi-center studies.

Primary diaphragmatic schwannoma with a typical target appearance: correlation of CT and MR imagings and histologic findings

A rare case of benign diaphragmatic schwannoma in a 38-year-old female is reported. Precontrast computed tomography (CT) showed an encapsulated well-defined round homogeneous tumor with central calcification, measuring approximately 5 cm in diameter, arising from the left diaphragm. Contrast-enhanced CT and gadolinium-enhanced T1-weighted magnetic resonance (MR) imaging showed focal enhancement in the central portion of the tumor. The tumor showed a typical target appearance of increased peripheral signal intensity and decreased central signal intensity on unenhanced T2-weighted images. Pathological examination of resected specimens of the tumor showed two zonal histological components: a hypercellular portion of spindle cells with nuclear palisading (Antoni A tissue) and a hypocellular portion of cells with cystic degeneration, together with focal calcification and hemangeomatous vascular changes (Antoni B tissue). We consider the radiological characteristics of diaphragmatic schwannoma on CT and MR imagings to represent the geographic difference between the histologic zones of the tumor.

Detection and characterization of residual disease in breast cancer

Although micrometastatic tumor cell spread largely determines the prognosis of patients with operable breast cancer, it is usually missed by conventional tumor staging. Several groups (including ours) have therefore developed immunocytochemical and molecular assays that allow the specific detection and characterization of individual carcinoma cells disseminated to bone marrow, blood, and lymph nodes. These assays may improve the prognostic precision of the current classification systems and may provide a tool for the early assessment of the therapeutic effects of anticancer drugs on micrometastatic cells in individual patients. Another aspect of such methods is that they enable detection of tumor cell contamination in stem cell grafts and validation of the efficiency of purging techniques. The most extensive experience exists with immunocytochemical methods, some of which have the potential to serve as a benchmark for less validated molecular methods. Still, the specificity and sensitivity of immunocytochemical detection of single cancer cells are affected by several variables, which include the intricacies of antigen expression, the lack of distinct morphological characteristics, the size of the analyzed sample, and the staining techniques for visualization of antibody binding. This article provides a critical review of the opportunities and pitfalls related to new methods for the detection and monitoring of minimal residual disease in breast cancer.