Fine-needle aspiration cytology of "ancient" schwannoma

Clinical and radiological features of intracranial ancient schwannomas: a single-institution, retrospective analysis

Ancient schwannoma (AS) is a subtype of schwannoma characterized by slow progression despite degenerative changes in pathology. Although it is considered a benign tumor, most previous reports have focused on extracranial AS; therefore, the clinical characteristics of intracranial AS is not clear. We included 174 patients who underwent surgery for sporadic intracranial schwannoma, and 13 patients (7.5%) were diagnosed with AS. Cysts were significantly more common in patients with AS than conventional schwannomas (92.3% vs. 44.7%, p < 0.001), as was bleeding (38.5% vs. 6.9%, p = 0.003) and calcification (15.4% vs. 1.3%, p = 0.029). The maximum tumor diameter was also larger in patients with AS (35 mm vs. 29 mm, p = 0.017). The median duration from symptom onset to surgery (7.0 vs. 12.5 months, p = 0.740) did not significantly differ between groups, nor did the probability of postoperative recurrence (p = 0.949). Intracranial AS was strongly associated with cyst formation and exhibited a benign clinical course with a lower rate of recurrence and need for salvage treatment. Extracranial AS is reportedly characterized by a slow progression through a long-term clinical course, whereas intracranial AS did not progress slowly in our study and exhibited different clinical features to those reported for extracranial AS.

Cytological features of cranial and paraspinal nerve Tumours

The 2021 World Health Organization Classification of Central Nervous System Tumours introduced significant revisions to the categorization of paraspinal and nerve sheath tumours. This updated system encompasses seven tumour types: schwannoma, neurofibroma, perineurioma, hybrid nerve sheath tumours, malignant melanotic nerve sheath tumour, malignant peripheral nerve sheath tumour and cauda equina neuroendocrine tumour. This review provides an image-rich cytologic reference of these tumours, with particular emphasis on intraoperative smear preparations. Knowledge of the key cytological features of these tumours and their differential diagnoses will help guide classification of these challenging entities.

The Utility of Fine Needle Aspiration (FNA) Biopsy in the Diagnosis of Mediastinal Lesions

Fine needle aspiration is a minimally invasive, low-morbidity, and cost-efficient technique for the sampling of mediastinal lesions. Additionally, ancillary testing on FNA samples can be used for the refinement of diagnoses and for treatment-related purposes (flow cytometry, cytogenetics, immunohistochemistry, and molecular diagnostics). Mediastinal lesions, however, can show a variety of lineages and morphologic features, giving rise to diagnostic dilemmas. As a result, the differential diagnosis can vary widely and becomes especially challenging due to the smaller sample size on FNA and the variability in component sampling. For appropriate patient management and to determine the correct treatment strategies, accurate pathologic diagnoses are paramount. In this review, we present the cytomorphologic features together with the immunophenotypic findings of mediastinal lesions, with emphasis on the diagnostic challenges and pitfalls in FNA cytology samples, including smears and cell block sections.

Cervical Sympathetic Chain Schwannoma-Our Experience

Tumours arising from the parapharyngeal space are uncommon. The most common tumour arising primarily from this region is a neurogenic tumour, especially Schwannoma. The most common site of origin of a Schwannoma in parapharyngeal space is Vagus nerve. Cervical sympathetic chain (CSC) schwannomas are extremely rare. Here, we discuss a case of a 30-year old female with cervical sympathetic chain schwannoma, the clinical presentation, diagnosis and management.

Incidental ancient schwannoma of the posterior mediastinum in a young male: a rare scenario

Ancient schwannoma is a distinctive type of schwannoma occurring mostly in the retroperitoneum. The presentation in the posterior mediastinum is rare. The term 'ancient' represents a group of neurogenic tumours showing degenerative changes with marked nuclear atypia. A 26-year-old man was incidentally detected to have an upper mediastinal mass lesion in the chest X-ray. MRI chest revealed a mixed signal intensity lesion in the left side upper para spinal region of the posterior mediastinum. The patient underwent left posterior thoracotomy and excision of the mass was done. Postoperative period was uneventful. The histopathological feature was typical of Ancient schwannoma. The patient is on regular follow-up and disease free until.

Giant Solitary Schwannoma of Submandibular Salivary Gland-A Rare Entity

Submandibular gland tumours, especially mesenchymal tumours, are extremely rare. Schwannoma of the salivary gland is a particularly rare form of an extracranial neurogenic tumor, of which ancient schwannoma is one of five variants. Since the first description, only a few ancient schwannomas have been reported in different locations in the head and neck region. In the submandibular gland it is very rare. This report presents a case of 26 year old male patient with an ancient schwannoma of the submandibular gland seems to be arising from parasympathetic fibers.

Ancient schwannoma of the cervical sympathetic chain

Ancient schwannomas exhibit characteristic histological features. Fine‐needle aspiration cytology (FNAC) is of limited use. Radiological evidence demonstrating displacement of blood vessels may aid diagnosis of schwannoma. Malignant transformation of ancient schwannoma has been reported. Surgical excision carries a high risk of postoperative Horner's syndrome.

A case of infected schwannoma mimicking malignant tumor

BACKGROUND

Infected schwannoma has been reported, this being one of the four cases published in the literature. Infected schwannoma has proven to be a tough diagnostic challenge to the treating tumor surgeon, mimicking infectious entities and most essentially, a malignant tumor.

CASE PRESENTATION

The authors report the case of a 64-year-old male with a soft tissue mass in his right gluteal area that presented initially with right leg pain, then later with signs of inflammation on the tumor area. Magnetic resonance imaging (MRI), computed tomography (CT), and thallium-201 scintigraphy studies confirm the presence of soft tissue mass which had continuity with sciatic nerve, with subsequent serial MRI findings suggesting tumor enlargement with cystic degeneration. Increased level of C-reactive protein (CRP) was observed before surgery. During an open biopsy upon tissue sampling, exudates with necrotic tissue were seen. Increased level of CRP and necrotic change suggested the possibility of malignant tumor. Histopathological diagnosis was schwannoma, and group B Streptococcus was detected by culture. After the confirmation of infected schwannoma, enucleation of the tumor was performed.

CONCLUSIONS

The report concludes that establishment of a benign pathology is essential when presented with similar clinical findings prior to definitive enucleation of an infected schwannoma.

Abdominal Wall Schwannoma

Neurilemmomas-or schwannomas-are rare soft tissue tumours involving peripheral nerve sheaths, usually found in the head and neck regions. They can infrequently originate within the tissues of the abdominal wall. Here, we present a case of symptomatic schwannoma of the abdominal wall in a 62-year-old woman referred for abdominal pain in the right iliac fossa. On physical examination, a 5-7-cm oval-shaped area of consolidation with regular borders and elastic consistence was palpable. Ultrasound examination of the abdomen revealed a hypoechogenic mass measuring 80-33-42 mm; subsequently, a CT scan confirmed the presence of a well-circumscribed mass, with small calcifications inside. Radical excision of the lesion under general anaesthesia was performed, and the histological examination was consistent with the diagnosis of "ancient" schwannoma. The patient was discharged on the second postoperative day, and, at a clinical check 1 month postoperation, she reported no recurrence of abdominal pain and had an improved quality of life. Schwannomas have a good prognosis overall, with malignant degeneration being very rare. Local recurrence is plausible only if non-radical resection of the primitive tumour occurs. This is the second case ever reported, to our knowledge, of symptomatic schwannoma of the abdominal wall. We advocate surgical removal of the tumour when it presents as a cause of abdominal pain, ensuring that a radical excision is performed due to the possibility-though rare-of malignant transformation or recurrence. This offers the possibility of total regression of symptoms through surgical therapy.

Giant solitary ancient schwannoma of the pleura masquerading as bronchopneumonia

We report a 53-year-old female who presented with complaints of sudden onset breathlessness, cough with expectoration for 6 months, and a right lung base lesion in the chest X-ray, which was diagnosed and treated as bronchopneumonia by the family physician. High-resolution computed tomography of the chest was done which revealed a large heterogeneously enhancing mass in the right thoracic cavity. She underwent thoracotomy and was found to have a giant encapsulated and well-circumscribed mass arising from the pleura. Excision biopsy of the mass revealed it to be an ancient schwannoma. Ancient schwannoma of the pleura is a very rare entity. Complete surgical resection is curative.

Ancient Schwannoma of Ansa Cervicalis: A Rare Clinical Entity and Review of the Literature

Ancient schwannoma is an uncommon variant of schwannoma, a benign tumor arising from the nerve sheath. It is reported to arise from any nerves except optic and olfactory. However, only six cases of ancient schwannomas arising from ansa cervicalis nerve have been reported to date in English literature. Proper preoperative evaluation is necessary to rule out other causes of neck mass such as thyroid lesions, lymphadenopathy, and carotid body tumor. We report a case of ancient schwannoma arising from the ansa cervicalis nerve. The origin of the lesion from ansa cervicalis was confirmed by intraoperative finding. Postoperative histopathological examination revealed degenerative changes including pleomorphism, cellular atypia, large nuclei with prominent nucleoli, and paucity of mitotic figures. Periphery of the mass showed nuclear palisading with characteristic verocay bodies. Immunohistochemical evaluation for S-100 showed diffuse positivity of the tumor cells, thereby confirming the diagnosis of schwannoma. We consider that schwannoma of cervical region can have origin from any nerve and should try to identify the origin pre- and intraoperatively. The postoperative complications depend on the nerve of origin and the precision of the surgery performed.

Symptomatic schwannoma of the abdominal wall: A case report and review of the literature

Schwannoma is a rare, benign tumor that arises from the nerve sheath. This tumor usually involves the extremities, but can also be found in the head and neck, trunk, pelvis, retroperitoneum, mediastinum and gastrointestinal tract. In numerous cases, the tumors are asymptomatic and are identified incidentally on physical examination or imaging. Occasionally, schwannoma is symptomatic due to compression of surrounding large nerves. In the present study, a 57-year-old female presented to the surgical outpatient’s department due to a well-localized parietal pain in the left lower quadrant. The onset of the pain occurred three years prior to presentation, without apparent cause and in the absence of other symptoms. Ultrasound and a computed tomography scan revealed a small solid tumor in the anterior abdominal wall, which was dimensionally stable over time, but was not noted in a preliminary analysis by a radiologist. The lesion was surgically removed using an anterior surgical approach. Histopathology revealed the tumor to be benign schwannoma. The painful symptoms completely disappeared. To the best of our knowledge, this is the third case of an abdominal wall benign schwannoma in the medical literature, and the first symptomatic case.

Rare case of chest wall schwannoma with destruction of rib, masquerading as a breast mass

Schwannomas are slow growing, benign, nerve sheath tumours of Schwann cell origin. They predominantly involve head, neck and flexor surfaces of upper and lower extremities, while the chest wall is an uncommon location for schwannomas. Schwannomas may rarely cause erosion of adjacent bone. We are reporting a very rare case of a chest wall schwannoma with destruction of rib which occurred in a 35-year-old female patient, which initially presented as a breast mass and was radiologically misinterpreted as a malignant soft tissue tumour.

Abdominal wall schwannoma: case report and review of the literature

A 29-year-old female had presented to surgical outpatient's department complaining of lump in the anterior abdominal wall. Ultrasound and magnetic resonance imaging revealed a solid degenerated tumor in the anterior abdominal wall. It was surgically excised, and histopathology confirmed it to be “ancient” schwannoma. To our knowledge, this is the second reported case of an abdominal wall ancient schwannoma in the medical literature.

Ancient schwannoma involving the median nerve: a case report and review of the literature

Ancient schwannomas are benign long standing schwannomas of the neural sheaths. Histological findings are these seen as in conventional schwannomas, but ancient schwannomas additionally demonstrate cystic hemorrhagic changes and degenerative nuclei with pleomorphism and hyperchromasia. Due to the nuclear atypia, and cystic degeneration, ancient schwannomas might be confused with malignant tumors on histology and imaging, leading to a radical surgical approach. The median nerve is rarely affected. We present a rare case of an ancient schwannoma involving the median nerve at the mid humerus. The tumor slowly grew up within ten years and become symptomatic with local pain, mild numbness in the distribution of the median nerve in the palm and Tinel's test. The tumor was successfully removed by separating it from the nerve fascicles to negative margins. Post-operatively local symptoms relieved but minor sensory loss in the median nerve distribution in the palm was noticed which improved in the following six months. Ancient schwannomas can be misdiagnosed as sarcomas due to specific imaging and histologic findings. Patients' physical examination, history and fine radiologic and pathology features should be cautiously interpreted in order to achieve correct diagnosis and avoid unnecessary wide tumor excisions.

Ancient schwannoma of the parapharynx causing dysphagia: a rare entity

A schwannoma is a benign, encapsulated tumour that is derived from neural sheath (Schwann) cells. Approximately 25-40% of schwannomas occur in the head and neck. The most common site is the parapharyngeal space of the neck; oropharyngeal occurrence is extremely rare. Among the various histological types of schwannomas reported to date, the ancient (degenerative) variant is the most rare. To our knowledge, this is the first report of an ancient schwannoma in the parapharynx with an extensive oropharyngeal component causing dysphagia. Dysphagia was the prominent symptom because of the location and volume of the lesion. The tumour was excised via a transcervical approach.

Laparoscopic resection of ancient schwannoma embedded in the psoas muscle

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

Ancient schwannoma of the thigh mimicking a malignant tumour: a report of two cases, with emphasis on MRI findings

Ancient schwannomas are rare, encapsulated tumours of long duration and are benign in nature. The tumour is solitary and may grow to a large size before detection of notable degenerative changes. The term "ancient schwannoma" is used to describe a tumour that has undergone such changes, typified by relative loss of Antoni type A tissue, perivascular hyalinisation, calcification, cystic necrosis, haemorrhage and the presence of degenerative nuclei that may be misinterpreted as sarcomatous pleomorphism. We report two cases of ancient schwannoma in the thigh mimicking malignancies. Identifying the fibrous capsule of the mass and a split fat sign using MRI is important for differentiating ancient schwannoma from other malignant tumours.

[Presacral schwannoma with degenerated areas ("ancient schwannoma")]

A presacral, degenerative schwannoma ("ancient schwannoma") is a rare entity. The clinical signs are nonspecific, and a reliable preoperative diagnosis is difficult. Tumor heterogeneity with calcifications may be seen in degenerated schwannomas on MRI or CT but not necessarily. First-line treatment is complete surgical excision. We present the case of a 44-year-old male who required surgery for a presacral mass. Histopathological examination revealed the diagnosis of a schwannoma with degenerated areas.

A patient with swelling of the eyelid: ancient schwannoma of the supraorbital nerve (2010:6b)

We present a case of swelling of the eyelid and supraorbital anesthesia caused by an intraorbital tumor. The differential diagnosis based on imaging consisted of aneurysmal bone cyst, schwannoma, neurofibroma, dermoid cyst, and cavernous hemangioma. The surgical and pathological diagnosis was an ancient schwannoma of the orbit, a rare entity.

Benign ancient schwannoma of the abdominal wall: an unwanted birthday present

Background

There has been a recent growth in the use of whole body Computerised Tomography (CT) scans in the private sector as a screening test for asymptomatic disease. This is despite scant evidence to show any positive effect on morbidity or mortality. There has been concern raised over the possible harms of the test in terms of radiation exposure as well as the risk and anxiety of further investigation and treatment for the large numbers of benign lesions identified.

Case Presentation

A healthy 64 year old lady received a privately funded whole body CT scan for her birthday which revealed an incidental mass in the right iliac fossa. This was investigated with further imaging and colonoscopy and as confident diagnosis could not be made, eventually excised. Histology demonstrated this to be a benign ancient schwannoma and we believe this to be the first reported case of an abdominal wall schwannoma in the English literature

Conclusions

Ancient schwannomas are rare tumours of the peripheral nerve sheaths more usually found in the head, neck and flexor surfaces of extremities. They are a subtype of classical schwannomas with a predominance of degenerative changes. Our case highlights the pitfalls of such screening tests in demonstrating benign disease and subjecting patients to what turns out to be unnecessary invasive investigation and treatment. It provides evidence as to the consequences of the large number of false positive results that are created by blind CT scanning of asymptomatic patients i.e. its tendency to detect pseudodiesease rather than affect survival rates. Should the number of scans increase there may be an unnecessary burden on NHS resources due to the large numbers of benign lesions picked up, that are then referred for further investigation.

Schwannoma of the tongue: two case reports and review of the literature

The aim of this study was to describe clinicopathologic and radiographic features of two cases of schwannoma involving the oral tongue and to review the literature of this unusual clinical entity. Case reports with review of the pathologic, radiologic and clinical data for two patients with schwannoma of the tongue are reported. Review of the literature of case reports of schwannomas (neurilemmomas) of the tongue from 1955 to 2006 with analysis of the patient's age, gender, presenting symptom(s), tumor size, and surgical approach was undertaken. The two patients in our series presented with painless swelling of the tongue. Transoral excision was performed and pathologic examination confirmed the diagnosis of schwannoma in both the cases. A total of 126 cases of schwannoma of the tongue have been reported in the English literature over the past 51 years. Schwannomas of the tongue typically present in the third decade of life (33%), display no gender predilection (52.8% female; 47.2% male) and often present as a painless mass (69.6%). Schwannomas are likely to elicit distressing symptoms when they occur in the posterior one-third of the tongue (63.2 vs. 13.5%) or approach 3 cm in greatest dimension (33.0 vs. 18.2 mm). The vast majority of cases have been treated with transoral excision (94.8%). Recurrence after surgical excision has not been reported. Schwannoma of the tongue is a relatively rare tumor of the head and neck. Transoral resection allows for removal of this tumor in a manner that precludes recurrence, avoids causing morbidity of tongue function, and remains the standard approach for the treatment of the vast majority of these tumors.

Diagnosis and management of retroperitoneal ancient schwannomas

BACKGROUND

Ancient schwannomas are degenerate peripheral nerve sheath tumors that very rarely occur in the retroperitoneum. They generally reach large proportions before producing symptoms due to mass effect. We describe three cases of retroperitoneal ancient schwannomas and discuss the diagnosis and management of these tumors.

CASE PRESENTATIONS

Three female patients with retroperitoneal ancient schwannomas were reviewed. One patient presented with several weeks of upper abdominal pain and lower chest discomfort, whereas back pain and leg pain with associated weakness were predominant symptoms in the remaining two. Abdominal imaging findings demonstrated heterogeneous masses in the retroperitoneum with demarcated margins, concerning for malignancy. The patients successfully had radical excision of their tumors. Histological examination showed encapsulated tumors that displayed alternating areas of dense cellularity and areas of myxoid matrix consistent with a diagnosis of ancient schwannoma.

CONCLUSION

A diagnosis of ancient schwannoma should be entertained for any heterogeneous, well encapsulated mass in the retroperitoneum. In these cases less radical surgical resection should be considered as malignant transformation of these tumors is extremely rare and recurrence is uncommon following excision.

Case of cystic schwannoma

Schwannoma is a well-defined tumor arising from the nerve sheath. It may present as a solitary mass in any part of the body, but is more commonly seen in the head, neck and extremities. We describe a 32-year-old female patient with a small dermal nodule on the forehead, which was 2 cm in diameter, round and of a cystic nature. Microscopic examination revealed that it consisted of compact spindle cells arranged partly in short bundles or a fascicular pattern with outstanding cystic degeneration manifested as a large, unilocular cavity in the center of the tumor tissue. The tumor cells were positive for S-100 protein and negative for epithelial membrane antigen (EMA), while the tumor capsule was positive for EMA. There was no S-100-positive membrane-like structure lining the cyst wall.

Special problems encountering surgical management of large retroperitoneal schwannomas

Background

Retroperitoneal schwannomas are rare, usually benign tumors that originate in the neural sheath and account for only a small percentage of retroperitoneal tumors. The aim of this clinical study is to present our experience in managing retroperitoneal schwannomas with a review of the current literature and to point out the surgical technical difficulties we faced, due to the tumor's strange behavior that eroded the vertebra in two cases without causing malignant invasion.

Methods

We reviewed the medical files of 69 patients treated in our department for retroperitoneal tumors from January 1991 until December 2006. Five patients had retroperitoneal schwannomas according to pathology report.

Results

There were two male and three female patients, with a mean age of 56 years (range 44–67 years). All patients were asymptomatic and none suffered from von Recklinghausen disease. Imaging workup included ultrasonography, computed tomography and magnetic resonance imaging. One patient, after having a non-diagnostic computed tomography fine needle aspiration (CT-FNA), underwent exploratory laparotomy and incisional biopsy that established the diagnosis of schwannoma. After complete excision of the tumors, postoperative course was uneventful in all patients. Tumors' maximum diameter was 12.7 cm (range 7–20 cm). No recurrences were detected during the follow up period (6–75 months).

Conclusion

Preoperative establishment of diagnosis is difficult in case of retroperitoneal schwannomas, however close relationship of retroperitoneal tumors with adjacent neural structures in imaging studies should raise a suspicion. Complete surgical resection is the treatment of choice. Histology and Immunohistochemistry confirms the diagnosis.

Ancient schwannoma presenting as a thoracic mass

BACKGROUND

Ancient schwannoma is a rare variant of schwannoma, histologically showing atypical features that may result in erroneous diagnosis of a malignant tumor. There are only few reported cases in literature.

CASE DESCRIPTION

We report a case of a 34-year-old man who was found to have giant mediastinal tumor. He underwent thoracotomy to remove the mass, which was proven to be ancient schwannoma on histopathology.

CONCLUSIONS

Clinical and radiological findings are important aids for further consideration of surgical removal of these potentially respectable tumors with good outcome.

Cytohistologic correlations in schwannomas (neurilemmomas), including "ancient," cellular, and epithelioid variants

Schwannoma accounts for one of the most common benign mesenchymal neoplasms of soft tissues. Although it is well defined in the cytology literature, particular histologic subtypes such as "ancient," cellular and epithelioid variants could be a source of diagnostic difficulties. We have reviewed cytology aspirates and corresponding histologic sections from 34 schwannomas diagnosed at Institut Curie. Histologically, 24 cases were classic, 5 were "ancient," 4 were cellular, and 1 was epithelioid schwannomas. No example of melanotic schwannoma was recorded. Original cytologic diagnosis was schwannoma in 13 (38.2%) cases, benign soft tissue tumor in 11 (32.4%), pleomorphic adenoma in 2 (6%) cases, angioma in 1 (2.9%) case, nodular fasciitis in 1 (2.9%) case, suspicious in 3 (8.8%) cases, and not satisfactory in 3 (8.8%) cases. There were no major differences between classical, "ancient," cellular, and epithelioid variants on cytology smears. Myxoid stroma, mast cells, and intranuclear inclusions were limited to classical subtype. Similarly, cyto-nuclear atypia was more frequent in classical subtype than in other subtypes. Schwannoma should be differentiated from well-differentiated malignant peripheral nerve sheath tumor, neurofibroma, and pleomorphic adenoma, in the last instance particularly for head and neck lesions.

Fine-needle aspiration of neurilemoma (schwannoma). A clinicocytopathologic study of 116 patients

The preoperative fine-needle aspiration cytology (FNAC) diagnoses in 116 surgically excised neurilemomas were reviewed and compared with the corresponding histopathologic diagnoses made on surgical specimens and with clinical data. In addition, the utility of adjunctive techniques was analyzed and other spindle-cell lesions in the differential diagnoses were discussed. An unequivocal, benign diagnosis was rendered by FNAC in 80 cases, 67 of which were correctly labelled as neurilemoma in a review of the original cytology reports. There were 6 false-positive malignant diagnoses while 23 smears were considered insufficient and 7 inconclusive as to whether benign or malignant. On reevaluation, the diagnostic smears in most cases contained spindle cells with wavy nuclei embedded in a fibrillar, occasionally collagenous, and/or myxoid matrix and Antoni A/Antoni B tissue fragments. A moderate to abundant admixture of round to oval cells was also frequent. Nuclear palisading was seen in 41 smears with distinctive Verocay bodies in 10. Markedly pleomorphic nuclei were seen in smears from 8 ancient and 6 conventional neurilemomas, and slight to moderate nuclear pleomorphism was observed in 38 additional cases. Thus most neurilemomas have distinct cytomorphologic features that allow correct diagnosis. The major problem in FNAC of neurilemoma is to obtain sufficient material. Furthermore aspirates showing predominantly Antoni A features, nuclear pleomorphism, and/or myxoid changes can easily be confused with other types of benign or malignant soft-tissue tumors.

A giant solitary schwannoma of the arm mimicking cyst hydatid

We present a 77-year-old female with a size of 9.5×9×7 cm³ giant schwannoma of musculocutaneous nerve volarly located in midarm, which was misdiagnosed as cyst hydatid on ultrasonographic and magnetic resonance image examination. There was not any neurologic sequele after the operation. In case of the similarity of their clinical and radiological findings, schwannoma should be included in the differential diagnosis of hydatid cysts especially in endemic countries.

Das „ancient schwannoma“

"Ancient schwannomas" of the mouth floor are rare, benign neoplasms derived from the nerve sheath of peripheral nerves. They show many degenerative changes such as necrosis and vascular thrombosis. Ancient schwannomas show histopathological features, such as degenerative changes and atypical nuclei, and may easily be confused with malignant neoplasms. B-scan sonography for the mouth floor and MRT imaging may be helpful in differential diagnosis. Here, we report on a patient with ancient schwannoma of the floor of the mouth.

Ancient schwannoma of the parotid gland: a case report and review of the literature

Schwannomas are encapsulated benign tumours arising from nerve sheath cells, of which ancient schwannoma is one of five variants. Since the first description, only a few ancient schwannomas have been reported in different locations in the head and neck region. In the parotid gland, this tumour is very rare. In this report, a 41-year-old female patient with an ancient schwannoma of the parotid gland is presented and the data of this patient compared with other (comparable) cases described in the literature.

Lobulated Schwannoma of the Median Nerve

The authors report an unusual case of volar wrist swelling with the appearance of a simple ganglion on magnetic resonance imaging (MRI); however, operative and histologic examination identified the swelling as an ancient schwannoma. Ancient schwannomas mostly present as a solitary tumor. A lobulated tumor in this location has not been described previously. The pathologic findings of these uncommon tumors and the difficulties encountered in accurate preoperative diagnosis are discussed.

Cytopathology-histopathology of the mediastinum

An appraisal of the cytopathology and corresponding histopathology of epithelial, germ cell, and lymphoid lesions of the mediastinum was previously reported in the Journal. This report aims to complete that topic with a discussion focusing on the correlative cyto-histopathology of the major mesenchymal, neural, and neuroendocrine neoplasms from this anatomic site. As previously stated, the mediastinum remains an uncommon site for fine needle aspiration (FNA) biopsy when compared with other anatomic sites. Yet, the recent use of endoscopic ultrasound-guided FNA for sampling mediastinal masses may increase this use. The purpose of this review is to focus on the shared and dissimilar morphologic features of this subset of neoplasms to improve diagnostic correlation between the two.

Fine-needle aspiration cytology of pleomorphic hyalinized angiectatic tumor: A case report

Pleomorphic hyalinized angiectatic tumor (PHAT) of soft parts is a neoplasm characterized by spindle and pleomorphic cells associated with an angiectatic vasculature. We describe the cytological findings of a fine-needle aspiration biopsy (FNAB) from the right medial knee of a 45-yr-old woman. The aspirate material was entirely submitted in Cytolit solution. The specimen was moderately cellular and was comprised of spindle cells in a background of fibrinous material. The cells varied from small, bland spindle cells with a fine chromatin pattern and inconspicuous nucleoli to larger pleomorphic cells with coarser chromatin and occasional intranuclear inclusions. Most of the cells were arranged singly with sporadic small cluster formation with indistinct cell borders. Rare mononuclear inflammatory cells morphologically compatible with mast cells were identified. The differential diagnosis include solitary fibrous tumor (SFT) and ancient schwannoma, which also shows fibrous-like material and spindle cells that may have intranuclear inclusions.

Pitfalls in fine needle aspiration cytology

A review of pitfalls encountered in fine needle aspiration cytology (FNAC) of all organs and tissues and based mainly on the author's 35-year experience of diagnostic FNAC in clinical practice is presented. Diagnostic difficulties are usually related to deviations from common cytological criteria that may occur in some lesions. Others are due to the effects of the sampling procedure or of the preparation of samples. A few basic rules are proposed, which may help to avoid some of the diagnostic pitfalls.

Ancient schwannoma masquerading as a thyroid mass

Schwannomas are benign, encapsulated nerve sheath cell neoplasms. Cervical sympathetic chain (CSC) schwannomas are rare, with less than 50 cited cases in the literature. CSC schwannomas may mimic a number of parapharyngeal masses. We report a rare variant, "ancient" schwannoma, which presented cytologically and radiologically as a thyroid mass. This is the first report of a CSC schwannoma mimicking a thyroid mass and the first report of an ancient schwannoma of the CSC.

Fine-needle aspiration cytology of pseudosarcomatous lesions of soft tissue

Pseudosarcomatous lesions are benign neoplasms of the musculoskeletal system that are likely to be misdiagnosed as malignant, based on clinical and histologic features. These include soft-tissue "tumors" considered reactive or reparative lesions such as nodular fasciitis and myositis ossificans. Also included in the "pseudosarcoma" category are benign neoplasms which show "pseudoanaplastic" cytologic atypia. The latter include lipoma, leiomyoma, angiomyolipoma, and benign peripheral nerve-sheath tumors. These neoplasms, particularly the reparative processes and the nerve sheath tumors, are increasingly being subjected to initial diagnosis by fine-needle aspiration cytology. Even by conventional cytology this group of lesions represents a well-known pitfall for the diagnostic pathologist. We review some cytologic features: repair-like change, cohesion of cellular fragments, and presence of "normal" elements in the aspirate, which may help the cytopathologist avoid misdiagnosis of these notoriously difficult entities.

On the utility and limitations of fine-needle aspiration of palpable lesions located in the hand

Various types of superficial and deep-seated lesions may occur in the hand, causing concern to the patient and posing diagnostic dilemmas to the clinician. A study was undertaken to evaluate the utility of fine-needle aspiration (FNA) or scraping for the diagnosis of palpable lesions located in the hand. From a clinico-cytologic point of view, lesions were classified as superficial (n = 41) or deep-seated (n = 66), and aspirates were categorized into five groups: benign without specific cytohistologic diagnosis, benign with specific cytohistologic diagnosis, atypical, malignant without specific cytohistologic diagnosis, and malignant with specific cytohistologic diagnosis. Out of 107 cases with aspirates adequate for cytologic evaluation, 85 had histologic correlation; in 22 cases, histologic confirmation was deemed unnecessary because of unequivocal cytologic findings and/or clinical workup. Sensitivity was 90.9%, specificity 100%, and efficacy 98%. Based on these findings, we believe that FNA or scraping may help in the clinical workup of patients with either superficial or deep-seated lesions located in this anatomic region.

Neurogenic tumors of the neck

Neurogenic tumors of the neck occur in children and adults. Important parameters to aid in the differential diagnosis are age at presentation, location, and a history of NF or multiple endocrine neoplasia. Schwannoma is the most common solitary neurogenic tumor in the neck and is usually seen in patients between 20 and 50 years of age. The plexiform neurofibroma and multiple localized neurofibromas are characteristic of NF1. MPNSTs are uncommon aggressive lesions that can arise de novo in patients with NF (10% to 30%) and postirradiation. Neuroblastic tumors consist of neuroblastoma, ganglioneuroblastoma, and ganglioneuroma. These tumors typically arise in the chest and abdomen but occasionally present as a primary neck mass. A neck mass with a histologic diagnosis of neuroblastoma is, however, more commonly metastatic from an abdominal neuroblastoma.

Fine-needle aspiration diagnosis of psammomatous melanotic schwannoma

A 51-yr-old male presented with an 8-mo history of lower back pain. Computerized axial tomography (CT) and magnetic resonance imaging (MRI) studies showed a 3.5 X 3.0 cm sacral mass within the spinal canal in the region of the left S2 nerve root. A fine-needle aspirate biopsy (FNAB) was performed under CT guidance. The cytologic findings included a spindle-cell population with a fibrillary background arranged in a vaguely streaming pattern, wavy nuclei with mild atypia, wispy cytoplasm, rare intranuclear inclusions, and dilated vascular spaces. Some cells contained a nonrefractile granular brown pigment consistent with melanin. Also identified were calcified concentric laminations typical of psammoma bodies. Immunohistochemically, the neoplastic cells were strongly immunoreactive for S-100 protein and HMB-45. A diagnosis of psammomatous melanotic schwannoma was rendered. No stigmata of Carney's complex were identified on physical examination. The patient has declined the recommendation of surgical excision of the mass. We herein describe a case unequivocally diagnosed as psammomatous melanotic schwannoma by FNAB.