Schwann Cells Of Nerve Fibers Research Articles

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

Introduction and importanceSchwannomas 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 presentationA 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 discussionCompression 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.ConclusionUnspecified 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.

Localisation of S100 Protein and Acetylated Tubulin in Sheep Pancreas

Abstract The pancreas plays a critical role in the control of nutritional homeostasis. It consists of two major parts, the exocrine pancreas, and the endocrine pancreas. In the present study S100 protein and acetylated α-tubulin were used to identify positive structures in both the exocrine and endocrine part of the ovine pancreas. In the exocrine part of the pancreas, a positive reaction to S100 protein was confined to centroacinar cells, intercalated, and intralobular ducts cells. In addition, the S100 protein was localized in the Schwann cells of nerve fibres. On the pancreatic islets, the S100 protein has been observed in Schwann cells of nerve axons, where they form a fine envelope that invests the islet surface. Inside the pancreatic islets, the Schwann cells positive for S100 protein envelope the endocrine cells of the islets. The difference in positivity of the S100 protein was found in relation to the endocrine cells. The relationship between endocrine cell positivity and positive exocrine duct cells was discussed. Acetylated α-tubulin (AT) was restricted to axons of the nerve fibres and was located within the connective tissue accompanying intralobular and inter-lobular ducts, and between secretory acini in close contact with secretory cells.

Presacral schwannoma: a bizarre presentation in the Pandora’s box of abdomen and pelvis

Schwannomas are benign tumors arising from the Schwann cells of nerve fibers. They are extremely rare in the pelvis accounting for only 1-3% of all schwannomas. These tumors are nonaggressive, slow growing, solitary neoplasms with an extremely low possibility of malignant transformation or recurrence after excision. We present a case of a 19 years old male with complaints of radiating pain from lower back to the left thigh associated with altered bowel and bladder habits. Following a detailed work up he underwent laparotomy and mass excision. Histopathological report revealed presacral schwannoma. Post-surgery patient improved symptomatically and is on regular follow up. There are a smaller number of cases of presacral schwannoma reported in the literature. Due to its outlandish striking presentation, diagnosis is very challenging. Although presacral schwannoma is rare, it should be considered as a differential diagnosis in the back of the mind of a surgeon while dealing a case of pelvic mass. In symptomatic and asymptomatic cases, surgical excision is the mainstay of treatment of these tumors.

Rare retroperitoneal conditions that mimic uterine myoma.

The most frequent tumoral condition of the uterus is represented by uterine myoma. The diagnosis, in most cases, is established by clinical examination and ultrasound scan. Nevertheless, there are rare cases, in which the surgical findings reveal a retroperitoneal tumor instead of a uterine myoma. These could be represented by schwannomas or Castleman disease. The schwannomas are rarely malignant and arise from the Schwann cells of nerve fibers. These tumors are frequently found at the level of the head, neck and mediastinum and rarely in the pelvis. Generally, schwannomas localized at retroperitoneal level are asymptomatic and with a very slow growth rate. The treatment consists in complete surgical resection. The recurrence rate is low and, generally, the prognosis is good. The Castleman disease is considered a rare entity, but it should be always taken into consideration when it comes to a differential diagnosis in a young patient who presents a retroperitoneal mass at imagery exams. The condition affects the lymphatic system and is characterized by a hyperplasia of the lymph nodes, sometimes associated with herpes virus infection. The clinical picture is often non-specific; the pain may be the only symptom. The imaging methods are not always conclusive for the final positive diagnosis and the histopathological examination is always necessary. Pelvic Castleman disease can be misdiagnosed as myoma or an adnexal tumor. In this article, we review the present knowledge regarding the pathogenesis, pathology and management of these rare retroperitoneal tumors. Both conditions, when located in pelvis must be taken into consideration in the differential diagnosis of uterine myomas, especially in the pedunculated form.

Two Unusual Presentations of Presacral Schwannoma; A Case Series

IntroductionSchwannomas are benign tumors that arise from the Schwann cells of nerve fibers. They commonly occur in the head and neck, mediastinum and extremities. However, they are extremely rare to be found in the pelvis. Case presentationWe report two cases of pelvic presacral schwannomas found in our hospital. The first case is a 50 years old lady who was seen in the outpatient clinic complaining of pelvic heaviness. Investigations were done including Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) which showed a solid mass in the presacral area. Biopsy was taken, and results came back as schwannoma. The patient underwent exploratory laparotomy and total tumor resection. The second case is a 19 years old gentleman who was referred from a local hospital to our hospital for further evaluation of an asymptomatic left retroperitoneal pelvic mass. The mass was found incidentally after a Road Traffic Accident. The patient underwent exploratory laparotomy and total tumor resection. In the two cases, specimen histopathology report came back positive for schwannoma and patients were doing fine in the post-operative period with no signs of recurrence till this date. ConclusionDue to the few cases in the literature, the diagnosis of presacral schwannoma is challenging. Some patients presented with vague symptoms like pelvic heaviness as seen with the patient in the first case, and some presented completely asymptomatic as seen with the patient in the second case. In symptomatic and asymptomatic cases, surgical excision is the mainstay of treatment of these tumors.

Giant intraosseous schwannoma of scapula: a rare case report and review of the literature

Bony schwannoma is a rare benign tumor derived from schwann cells of nerve fibers in the bone. It accounts for less than 1% of bony benign tumor, and prone to occur in the sacrum and mandible, occurrence in scapula is very rare. Here we report a 42-year-old woman with the chief complaint of pain in the left scapula. Imaging examination showed a giant, irregular, swelling lesion with distinct border involving the left scapula, extending into the left shoulder glenoid and pressing the surrounding soft tissues. Needle biopsy showed that the tumor was composed of spindle cells with S-100 protein positive, mimicking a benign neurogenic tumor. Then a complete excision was performed by removing the tumor and the surrounding tissues including partial left shoulder glenoid. Histologically, Antoni type A areas were the predominant microscopic pattern with occasional alternation by Antoni type B areas. Immunohistochemistry found that the neoplastic cells were scatteredly positive for S-100 protein. All these features suggest a diagnosis of an intraosseous schwannoma of the left scapula. Follow-up of the patient for ten months found no recurrence or sign of other tumors following complete tumor resection without any adjuvant therapy. In conclusion, this case of giant intraosseous schwannoma of the scapula is a rare benign bony tumor, and its diagnosis combined with clinical, imaging and pre-operative needle biopsy is important to guide further therapy, and avoid overtreatment.Virtual slidesThe virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1399352761104042

Intraosseousschwannoma: A Case Report and Review

Bony schwannoma is a rare benign tumour derived from Schwann cells of nerve fibres in the bone. It accounts for less than 1% of bony benign tumour, and prone to occur in the sacrum and mandible, occurrence in scapula is very rare. Here we report a 50-year-old woman with the chief complaint of pain in the left scapula. Imaging examination showed a giant, irregular, swelling lesion with distinct border involving the left scapula, extending into the left shoulder glenoid and pressing the surrounding soft tissues. Needle biopsy showed that the tumour was composed of spindle cells with S-100 protein positive, mimicking a benign neurogenic tumour. Then a complete excision was performed by removing the tumour and the surrounding tissues including partial left shoulder glenoid. Histologically, Antoni type A areas were the predominant microscopic pattern with occasional alternation by Antoni type B areas. Immunohistochemistry found that the neoplastic cells were scatteredly positive for S-100 protein. All these features suggest a diagnosis of an intraosseousschwannoma of the left scapula. Follow-up of the patient for ten months found no recurrence or sign of other tumours following complete tumour resection without any adjuvant therapy. In conclusion, this case of giant intraosseousschwannoma of the scapula is a rare benign bony tumour, and its diagnosis combined with clinical, imaging and pre-operative needle biopsy is important to guide further therapy, and avoid overtreatment.

Cystic schwannoma of the pelvis

Schwannomas are benign tumours that arise from the Schwann cells of nerve fibres. They commonly occur in the head and neck, mediastinum and extremities. They are extremely rare in the pelvis. These are usually slow growing tumours and are often detected incidentally. Pre-operative diagnosis is extremely difficult as there are no definitive signs on imaging. Aspiration biopsy is often inconclusive or misleading. Surgical excision is both diagnostic and therapeutic. As these tumours are often large in size, open excision is most commonly performed. We describe a case of a large, cystic schwannoma of the pelvis causing bladder outlet obstruction and bilateral hydroureteronephrosis. Complete surgical excision was performed laparoscopically.

Immunohistochemical identification and comparison of glial cell lineage in foetal, neonatal, adult and neoplastic human adrenal medulla.

The differentiation of glial cells in developing, neonatal, adult and neoplastic human adrenal medulla has studied immunohistochemically. From 8 to 28 weeks' gestational age, S-100 protein and its beta-subunit revealed two different glial cell populations in adrenal glands, namely Schwann-like and sustentacular cells. Schwann-like cells were spindle-shaped cells forming a continuous layer around groups of sympathetic neuroblasts, often in contact with Schwann cells of nerve fibres entering neuroblastic groups. Sustentacular cells were round or oval cells with dendritic cytoplasmic processes; they were not associated with nerve fibres and mingled both with sympathetic neuroblasts and differentiating chromaffin cells. The developmental fate of Schwann-like cells was different from that of sustentacular cells. Schwann-like cells disappeared from the 28th week of gestational age, in association with the disappearance of sympathetic neuroblastic groups, and they were rarely found in neonatal and adult adrenal medulla. In contrast, sustentacular cells persisted between medullary chromaffin cells, and their number and dendritic cytoplasmic processes progressively increased from foetus to adult. In eight cases of primitive adrenal neuroblastic tumours of neonatal age (five undifferentiated neuroblastomas and three ganglioneuroblastomas), Schwann-like cells were found at the periphery of tumoral nests with a lobular growth pattern, while rare sustentacular cells were associated with neuroblasts. In two cases of adult phaeochromocytomas, only sustentacular cells were detected between chromaffin tumoral cells. Our findings suggest that the glial cell types and their distribution in primitive adrenal medulla tumours closely resemble those observed during development in the groups of adrenal sympathetic neuroblasts and in the clusters of chromaffin cells.

Immunohistochemical distribution of S-100 protein and type IV collagen in human embryonic and fetal sympathetic neuroblasts

The expression and distribution of S-100 protein and type IV collagen was studied immunohistochemically in sympathetic neuroblasts from the paravertebral region to the adrenal glands in human embryos and fetuses ranging from 7 to 12 weeks gestational age. From 7 weeks gestational age, S-100 protein was detected in round or oval cells mingling with sympathetic neuroblasts, and in spindle-shaped cells forming a continuous layer around them. The latter S-100 protein-positive cells were found in contact with the Schwann cells of nerve fibres entering the groups of sympathetic neuroblasts. Staining for type IV collagen showed that all groups of sympathetic neuroblasts were surrounded by a continuous basement membrane. By examining serial sections stained for type IV collagen and S-100 protein, a continuous basement membrane was found along the distribution pattern of the peripheral S-100 protein-positive spindle cells. The morphology of these cells, and their relationships with Schwann cells and with the basement membrane of the sympathetic neuroblasts, indicated that they were Schwann-like cells probably capable of synthesizing a continuous basement membrane separating the neuroblasts from the adjacent tissues. In contrast, the round or oval S-100 protein-positive cells, in contact with the sympathetic neuroblasts and not associated with nerve fibres, were considered as sustentacular or sustentacular precursor cells. At week 7 gestational age, the peri-adrenal sympathetic neuroblasts and their sustentacular and Schwann-like cells started to invade the adrenal glands and mingled with the adrenal cortical cells. These findings suggest the extra-adrenal origin of the sustentacular cells in embryonic and fetal adrenal glands.

Pathology and pathogenesis of predilective sites of nerve damage in leprous neuritis. Nerves in the arm and the face.

A very brief review of the literature on the clinicopathological aspects of leprosy is given; mainly through references. The salient features of the two main types of leprosy--tuberculoid and lepromatous--are presented in a Table. The surgical and pathological findings are briefly described and the pathogenesis of involvement of the facial nerve (a motor nerve) is discussed. On the basis of (i) the severe histopathologic changes (degeneration) of the most distal part of the zygomatic branch of the facial nerve (innervating the orbicularis oculi), with sparing of the roots of all branches and the trunk of the nerve; (ii) the concurrent loss of cutaneous sensations in the territory of the maxillary division of the trigeminal nerve (the region of the zygoma and the lower eyelid); and (iii) the close approximation or even anastomoses occurring between the ultimate branches of these two nerves, it is postulated that paralysis of orbicularis oculi occurs secondarily to the sensory nerve damage, i.e. due to spread of infection from the sensory branches of the trigeminal to the motor branches of the facial nerve. The surgical and pathological findings of the nerves in the arm, especially the ulnar and the median and their branches are described, in tuberculoid and lepromatous leprosy. The forms of nerve degeneration, the occasional axon regeneration, and the role of the Schwann cell in harbouring the bacilli, are illustrated. The lysosomal enzyme activity in the Schwann cells of nerve fibres, particularly of unmyelinated fibres which preferentially phagocytose the M. leprae, and their role, albeit not very successful, in degrading the bacilli and controlling the infection, are also stressed, through light and electronmicrographs. The constellation of secondary factors of the terrain operating to produce further damage to primarily diseased nerves, is discussed. These factors include indirect compression from unyielding fibroosseous tissues, minor traumata, stretching of the nerves, and their exposure to lower temperatures in subcutaneous tissues.