Unusual dural and skull-based mesenchymal neoplasms: a report of four cases

Giant primary intracranial multi-fossa leiomyosarcoma involving the frontal sinus, ethmoid air cells, anterior fossa, middle fossa, and intraventricular space: A case report and literature review

Background

Leiomyosarcomas (LMSs) is a type of sarcoma that arises from smooth muscle and generally presents in the abdomen. Although intracranial LMS has been identified before, most reported presentations have been in immunocompromised patients. Here, we present an intracranial LMS in an immunocompetent patient.

Case Description

A 22-year-old male with a history of an atypical pineal parenchymal tumor of intermediate differentiation resected by suboccipital craniotomy at the age of 12 followed by adjuvant radiation therapy, presented with 3 weeks of decreased appetite, weight loss, and lethargy. He subsequently underwent transbasal approach skull base tumor resection. Histologic examination of the mass along with the patient's history of radiation was supportive of a low-grade, radiation-induced LMS arising from the anterior fossa of the skull or meninges and extends to the frontal sinus and ethmoid air cells.

Conclusion

Primary intracranial LMS is an extremely rare diagnosis and presenting symptoms vary with the location and size of the tumor. Due to the poor specificity of clinical symptoms, diagnosis is often based on histology. The most common treatment is surgical resection. Adjuvant chemotherapy with various agents has been found to be somewhat effective outside the central nervous system. When LMS does occur, a history of immunocompromised state or previous radiation exposure is often present. Pathological confirmation is required for an appropriate diagnosis.

Olfactory groove monophasic sinovial sarcoma and von Recklinghausen's disease: A case report and literature review

BACKGROUND

Soft-tissue sarcomas are a rare and diverse group of neoplastic lesions. They represent only 1% of malignant tumors in adults and 15% in children. Synovial sarcoma (SS) is a type of soft-tissue sarcoma, accounting for 5-10% of cases, and commonly affecting extremities. Diagnosis, treatment, and prognosis remain challenging especially when localized in uncommon areas, such as intracranial lesions.

CASE DESCRIPTION

A 13-year-old male patient with a clinical history of neurofibromatosis Type I (NF1) presenting holocranial headache with jet vomiting and apathy 2 days before admission, without neurological deficits and/or focal findings. On magnetic resonance imaging: an extra-axial infiltrative lesion with contrast uptake at the base of the skull in the olfactory groove topography. After total tumor resection, the anatomopathological examination showed monophasic SS. The patient returned after 6 months with similar symptoms, and the lesion recurred and was reoperated. Unfortunately, 7 months after the second surgery, the patient died.

CONCLUSION

SS can occur extraarticulously and with a variable clinical presentation and poor prognosis despite adjuvant therapies with radiotherapy and chemotherapy. In individuals with clinical history of NF1, there is still no direct correlation between the two manifestations, although current descriptions are suggestive of a possible interaction.

Primary intracranial synovial sarcoma: A case report and review of literature

Background:

Primary intracranial synovial sarcomas (PrISS) are unusual dural based mesenchymal tumors seen most commonly in the supratentorial compartment. They can mimic a spontaneous intracranial hemorrhage or a high-grade glioma on imaging.

Case Description:

A 31-year-old male presented with headache and right hemiparesis for 2 weeks. CT brain revealed a left frontal spontaneous intracerebral hemorrhage. PrISS revealed a heterogeneously ring enhancing solid cystic lesion with attachment to convexity dura. Intraoperatively, it mimicked a high-grade glioma. Histopathology report showed features of a synovial sarcoma, which was later confirmed with IHC. Classical SYT-SSX2 translocation was confirmed only on RTPCR after fluorescent in situ hybridization (FISH) was negative for same. Whole body positron emission tomography (PET-CT) did not show any extracranial tumor. Despite radiotherapy, there were recurrence and tumor progression at 6 months and the patient succumbed 11 months later.

Conclusion:

PrISS is an unusual aggressive intracranial neoplasm that carries a worse prognosis when compared nonintracranial synovial sarcomas. Molecular cytogenetics (FISH and RTPCR) are essential for confirming the diagnosis, though FISH seems to have a lower sensitivity and can yield false negative results as was noted in this case.

Recurrent primary intracranial synovial sarcoma, a case report and review of the literature

Synovial sarcoma (SS) occurs in various parts of the body, predominantly in the extremities. It also occurs in organs without synovial structures. The intracranial disease has been reported as metastasis, but primary intracranial SS has been reported rarely. We report a patient with hemiplegia and a mass on the brain CT. Pathology showed SS with no extracranial pathology.

Synovial sarcoma (SS) is one of the most common sarcomas of soft tissue, and it mostly occurs in the lower extremities. It can cause metastasic disease, especially in the lungs, bones, and lymph nodes. Metastasis in the brain is very rare. Primary intracranial SS has also been reported in extremely rare cases. In this article, we study the case of a 28‐year‐old man with primary intracranial SS.

Primary intracranial smooth muscle tumor associated with Epstein-Barr virus in immunosuppressed children: two cases report and review of literature

Primary intracranial smooth muscle tumors are rare. Most cases are related to Epstein-Barr virus proliferation in immunocompromised patients such as organ solid recipients. Only a few cases have been reported in pediatric patients. The clinical features are very variable depending mainly on the location and size of the smooth muscle tumor (SMT) and the pathogenesis is poorly understood. We describe two cases of intracranial SMT localized in the temporal lobe and associated with EBV in immunosuppressed children. A review of the literature associated with intracranial leiomyomas was also done.

Intracranial primary synovial sarcoma mimicking a spontaneous cerebral hematoma-a case report and review of the literature

BACKGROUND

Synovial sarcoma is a soft tissue sarcoma, of uncertain histological origin, usually located near large joints and concerning mainly young adults. Intracranial presentation in the form of metastasis from a primitive body sarcoma has been rarely reported. However, intracranial primitive synovial sarcoma (IPSS) is extremely rare and only a few cases have been reported in the literature.

CASE DESCRIPTION

We present the case of a 48-year-old man, with no particular medical history, that was referred to our hospital for severe headache with a normal neurological exam and a CT cerebral scan showing a left frontal lobe hematoma. The initial cerebral CT scan didn't show any vascular malformation and the body CT scan was negative for a primitive lesion. A close follow-up with a cerebral MRI three months later, demonstrated a T1 enhanced lesion with an important volume progression. The patient underwent a complete surgical removal of this lesion and the first pathology diagnosis was compatible with a meningioma. After further proofreading by an expert and molecular analysis, the diagnosis of monophasic synovial sarcoma was confirmed. Nine months after the first surgery, the follow-up MRI showed the progressive recurrence of the lesion and in this context the patient underwent a second surgery with total resection of the tumor and frontal thin margin excision. Afterwards, the patient was treated with adjuvant radiotherapy, with a good clinical evolution, and till now the follow-up shows no recurrence.

CONCLUSION

IPSS is an extremely rare sarcoma, with challenging diagnosis and difficult management. Specific molecular analysis is necessary. Complete resection followed by radiotherapy seem to be the most appropriate therapeutic approach. However, the prognosis is still poor. Our case is even rarer because of the initial presentation as a cerebral hematoma.

Skull Base Leiomyomas and Angioleiomyomas: A Systematic Literature Review and an Uncommon Case Report

BACKGROUND

Skull base leiomyomas (LMs) and angioleiomyomas (ALMs) are rare, and the understanding of this disease is limited. We present a systematic literature review of skull base LM and ALM and report a case of internal auditory canal (IAC) ALM.

METHODS

A systematic review was conducted following the PRISMA guidelines. PubMed and Embase were systematically queried for skull base LM and ALM, and Rayyan QCRI was used for the review. After applying exclusion criteria, individual articles were evaluated for quality control, data collection, and analysis. The presentation, management, and outcome of a 37-year-old man with a right-sided IAC ALM are described.

RESULTS

Of 68 unique entries, 27 studies were included. Thirty-four cases of skull base LM (n = 6) or ALM (n = 28) were identified. Average age at presentation was 45.1 ± 14.5 years, and 52.9% of patients were male. Tumor diameter was 2.75 ± 1.6 cm, with headaches being the most reported symptom. Commonly reported locations were the cavernous sinus and the external auditory canal. Only 3 cases of IAC ALM met the criteria for this review. All tumors were treated with surgery, and gross total resection was achieved in 27 patients. Radiation was given in 3 cases with subtotal resection.

CONCLUSIONS

Skull base LM and ALM are rare. Given the need for pathology, surgery has been the standard treatment for symptomatic skull base LM and ALM. It is important to understand the available data about this disease and consider it in the differential of skull base lesions.

Sarcomas of the sellar region: a systematic review

PURPOSE AND METHODS

Sarcomas of the sellar region are uncommon and unexpected tumors. Here, we review the cases reported in literature via a systematic search.

RESULTS

Ninety-four patients, 58.5% male with mean age of 39.2 ± 17.2 years were included. Fifty-seven (62%) had soft tissue sarcomas (STS) and 35 (38%) bone sarcomas (BS). Sarcoma was a primary tumor in 66%, developed after radiotherapy in 31.9% and 7.4% were metastatic. Median time between radiotherapy and sarcoma development was 10.5 (11) years. Main presentation symptoms were visual disorders (87.9%), headache (61.5%) and III cranial nerve palsy (24.1%). After surgery, sarcoma persisted or recurred in 82.3% and overall mortality reported was 44.6% with 6.5 (14) months of median survival. Tumor appeared earlier in BS compared to STS (34.4 ± 15.1 vs. 42.6 ± 17.6 years), p = 0.034 and complete tumor resection was achieved more often (41.3% vs. 4.4%), p =  < 0.001. Condrosarcoma and rhabdomyosarcoma were more frequent subtypes among primary tumors while fibrosarcoma was among post-radiation sarcomas. Tumor size was larger in radiation associated sarcomas (mean maximum diameter 46.3 ± 9.3 vs. 29.1 ± 8.0 mm, p = 0.004) and persistency/recurrence was similar in both groups (70.1 vs. 73.3%, p = 0.259).

CONCLUSION

Sarcomas appear as mass effect symptoms in the middle aged population, mainly as primary tumors, but one third is associated with radiotherapy. Surgery is commonly not curative, mortality rate is high and death ensues shortly after diagnosis.

Surgical management and long-term outcomes of primary intracranial leiomyosarcoma: a case series and review of literature

Primary intracranial leiomyosarcomas (PILMSs) are extremely rare neoplasms, and their management remains unclear. The authors aimed to enunciate the radiological features and design a treatment protocol based on previously published cases combined with our series. Clinical data from all 12 cases of PILMS treated at their institute between 2008 and 2018 were reviewed. Meanwhile, they searched the Ovid MEDLINE, Embase, PubMed, Web of Science and Cochrane databases using the keywords "leiomyosarcoma" and "intracranial," "central nervous system," "cerebral," or "brain" Previously published data were processed and used according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The authors' cohort included 4 males (33.3%) and 8 females (66.7%) ranging in age from 13 to 67 years with a mean of 44.1 ± 5.0 years. Gross total resection (GTR), subtotal resection, and partial resection were achieved in 8 (66.7%), 3 (25%), and 1 (8.3%) patient, respectively, and only four patients (33.3%) received adjuvant therapy after surgery. After a mean follow-up of 30.5 ± 7.6 months, 6 patients (50%) experienced recurrences, and all of them died at the final. Twenty-seven patients (15 were male and 12 were female), in the literature cases, were identified between January 1980 and November 2019, presenting with PILMS. GTR and non-GTR were achieved in 21 (77.8%) and 6 (22.2%) patients, respectively. Postoperative radiotherapy was administrated in 17 patients (63.0%), and postoperative chemotherapy was administrated in 9 patients (33.3%), After a mean follow-up of 22.2 ± 4.1 months, recurrence and death occurred in 8 (36.4%) and 4 (14.8%) cases, respectively. In the pooled cases, the univariate analysis model revealed that only GTR was a significantly favorable factor for increased progression-free survival (hazard ratio 0.270, 95% confidence interval = 0.093-0.787, p = 0.016) and overall survival (hazard ratio 0.255, 95% confidence interval = 0.073-0.890, p = 0.032). GTR was recommended as an optimal treatment; meanwhile, postoperative radiation was also a choice to help increase the survival of patients of PILMS.

Intracranial Leiomyoma Associated with Epstein-Barr Virus: A Cerebellopontine Angle Mass Presenting with Trigeminal Neuralgia

BACKGROUND

Primary intracranial leiomyoma is a rare smooth muscle tumor often associated with Epstein-Barr virus (EBV), with <30 cases reported worldwide. These tumors commonly occur in patients with immunocompromised status, especially those with human immunodeficiency virus. In the present report, we have described the case of an EBV-associated leiomyoma at the cerebellopontine angle. The patient had presented with trigeminal neuralgia, which, to the best of our knowledge, is the first reported anatomical location and presentation for this tumor type.

CASE DESCRIPTION

A 41-year-old male patient had presented with right-sided facial pain in the V1 and V2 dermatomes and previous workup and imaging studies. The patient had undergone treatment of a presumed right-side cerebellopontine angle meningioma as determined by the magnetic resonance imaging characteristics (no biopsy). The patient subsequently underwent right-sided retrosigmoid craniotomy and gross total resection of the tumor. The postoperative period was uneventful with resolution of the trigeminal neuralgia. Histopathologic examination revealed spindle cell neoplasm with histopathologic and immunohistochemical features consistent with leiomyoma. The tumor cells were positive for smooth muscle actin and desmin and were negative for S100, SOX-10, epithelial membrane antigen, glial fibrillary acidic protein, progesterone receptor, CD31, CD34, and E-cadherin.

CONCLUSIONS

Primary intracranial leiomyomas are rare tumors associated with EBV infection that occur in immunocompromised patients. These lesions should be considered in the differential diagnosis for patients with known immunocompromised status (e.g., human immunodeficiency virus), and tissue biopsy should be considered.

Primary intracranial intraventricular leiomyoma: a literature review

Leiomyomas, benign tumors of well-differentiated smooth muscle and vascular collagenous tissue, usually occur in the uterus but can develop wherever smooth muscle is present. Primary intracranial leiomyomas are rare tumors. We present the case of a 40-year-old woman with a primary intraventricular leiomyoma. She consulted us for headache, dizziness, and black spots in her vision. Magnetic resonance images (MRI) disclosed a mass rooted in the posterior septum pellucidum. The tumor was totally excised by the senior author with no residual seen on intraoperative MRI. Pathological examination showed it to be a benign spindle-cell neoplasm. On the 6th month control MRI, there was no recurrence. We also reviewed articles relevant to primary intracranial leiomyomas.

What's that big thing on your head? Diagnosis of a large frontoparietal lesion on an Eastern Zhou skull from Henan, China

We carried out a differential diagnosis of a large frontoparietal lesion on a human skull from a Late Bronze Age archaeological site located on the Central Plain of China, dating to between 771 and 476 BC. The head of this individual was covered in cinnabar, a mercury-based pigment that later was used for medicinal purposes in China. The lesion was well-circumscribed and involved the outer and inner tables of the skull, slight diploë thickening, and coarsening of bone trabeculae with expansion of intertrabecular spaces. We show that the observed changes are most consistent with cavernous hemangioma of the skull, a benign vascular malformation that preferentially affects older adults. Hemangiomas are often neglected in the paleopathological literature because of their benign nature - they tend to be asymptomatic and do not affect quality of life to a significant degree. Nevertheless, they produce characteristic lesions that can be confused with several other conditions with unrelated etiologies, including congenital hemoglabinopathies, traumas, malignant or benign neoplasms, and Paget's disease. We outline the diagnostic criteria that distinguish cavernous hemangioma from other conditions affecting the skull.

Intracranial synovial sarcoma: A clinical, radiological and pathological study of 16 cases

INTRODUCTION

Synovial sarcoma (SS) is a tumor of unknown origin and is extremely rare in the central nervous system. Most studies on intracranial SS included only one or two cases. To better understand the disease, we review a series of primary intracranial SS.

METHOD AND MATERIALS

16 primary intracranial SS in Tiantan Hospital during 2008-2017 were included. The clinical characteristics, including radiological and histological examination, operative records, and prognoses were reviewed.

RESULT

The case series included nine male and seven female patients with an average age of 23.8 years. Radiological results showed that the supratentorial region (81.25%) was the most common site of the brain involved. All patients were misdiagnosed as non-SS tumors. Gross total resection (GTR) was achieved in 12 cases (75.0%), and subtotal resection (STR) was achieved in 4 cases. All cases showed the characteristic SYT-SSX fusion gene, as detected by RT-PCR. The mean progression-free survival time (PFS) was 10.0 months and the mean overall survival time (OS) was 15.5 months. Multivariate analysis revealed that GTR and postoperative adjuvant radiotherapy were independent factors for PFS (HR = 6.143, 95% CI = 1.491-25.312; P = 0.012, HR = 6.143, 95% CI = 1.491-25.312; P = 0.012 respectively) and OS (HR = 9.000, 95% CI = 1.627-49.773; P = 0.012, HR = 0.017, 95% CI = 0.001-0.213; P = 0.002 respectively).

CONCLUSION

Intracranial SS were more frequently observed in the supratentorial region and in young patients without sex predilection. We recommend adjuvant radiation regardless of the extent of resection. More patients and longer follow-up periods were needed to further elucidate the biological features of intracranial SS.

HIV-associated cavernous sinus disease

Introduction

The underlying diagnosis of cavernous sinus disease is difficult to confirm in HIV-coinfected patients owing to the lack of histological confirmation. In this retrospective case series, we highlight the challenges in confirming the diagnosis and managing these patients.

Results

The clinical, laboratory and radiological data of 23 HIV-infected patients with cavernous sinus disease were analysed. The mean age of patients was 38 years. The mean CD4+ count was 390 cells/μL. Clinically, patients presented with unilateral disease (65%), headache (48%), diplopia (30%) and blurred vision (30%). Third (65%) and sixth (57%) nerve palsies in isolation and combination (39%) were most common. Isolated fourth nerve palsy did not occur. Tuberculosis (17%) was the most commonly identified disorder followed by high-grade B-cell lymphoma (13%), meningioma (13%), metastatic carcinoma (13%) and neurosyphilis (7%). In 22% of the patients, there was no confirmatory evidence for a diagnosis. The patients were either treated empirically for tuberculosis or improved spontaneously when antiretroviral therapy was started. Cerebrospinal fluid was helpful in 4/13 (31%) of patients where it was not contraindicated. Only 3/23 (13%) of the patients had a biopsy of the cavernous sinus mass. The outcomes varied, and follow-up was lacking in the majority of patients.

Conclusion

In HIV-infected patients, histological confirmation of cavernous sinus pathology is not readily available for various reasons. In resource-limited settings, one should first actively search for extracranial evidence of tuberculosis, lymphoma, syphilis and primary malignancy and manage appropriately. Only if such evidence is lacking should a referral for biopsy be considered.

Skull base angiomatous leiomyoma: a case report and review of literature

Leiomyomas, benign neoplasms of mesenchymal origin, are common in gastrointestinal and genitourinary tracts. They are comprised of well-differentiated smooth muscle cells with few mitotic figures. Leiomyomas should not exhibit metastatic potential, though metastasis has been reported. Primary intracranial lesions remain rare. Only 4 cases have been reported in immunocompetent patients. Here we report an intracranial leiomyoma in an immunocompetent patient. A 60 year-old woman with unremarkable past medical history presented with a right sixth nerve palsy. On examination, there was a right sixth nerve palsy with numbness over the right V2 and V3 areas. CT scan showed a well-defined lesion within the right middle cranial fossa adjacent to the cavernous sinus with bony remodelling of the lateral wall of the sphenoid sinus and greater wing of the right sphenoid. MRI showed extra axial mass lesion arising from the right Meckel´s cave/cavernous sinus. The lesion was T2 hyperintense and T1 isointense. Homogenously enhancing centrally with little enhancement peripherally. CT CAP showed no primary lesions. Differential diagnosis at that stage was between meningioma, schwannoma or metastasis. The patient underwent craniotomy and debulking of tumour. Histological analysis confirmed leiomyoma. Post-operative MRI showed residual enhancement in the region of Meckel's cave. As residual tumour was significant, the patient underwent STRS. Further MRI at 1 year showed regression of the tumour. Majority of intracranial leiomyomas are discovered in immunocompromised patients incidentally. Histology reveals spindle shaped cells with blunt ends and few mitotic figures. The best treatment option to date for primary intracranial leiomyomas remains surgical gross total resection without adjuvant radiation therapy. Intracranial leiomyoma transitioning to leiomyosarcoma post radiotherapy has been reported before and therefore follow up with serial imaging is warranted.

Intractable Repeated Intracerebral Hemorrhage Due to Primary Dural Leiomyosarcoma: Case Report and Literature Review

BACKGROUND

There are few case reports of primary leiomyosarcoma originating from the dura mater. We herein report a case of primary dural leiomyosarcoma that presented with repeated intracranial hemorrhage.

CASE DESCRIPTION

A 62-year-old man presented with a 4-year history of a temporo-occipital bump. He showed a disturbance with reading words. The sudden onset of occipitalgia occurred 13 days after the onset. Computed tomography revealed a left temporal subcortical hematoma and thin subacute subdural hematoma associated with a temporal osteolytic mass lesion extending into the subcutaneous layer. The hematoma and tumorous mass lesion were removed. The subcutaneous tumor mass penetrating the skull bone originated from the dura mater and extended into the transverse sinus. No invasion into the cortical surface was observed. The lesion adjacent to the transverse sinus was not resected, and the remnant lesion was irradiated with local radiation therapy of 60 Gy. A left subdural hematoma and intrasylvian subarachnoid hemorrhage occurred 3 months after the first surgery, and a second removal was performed. Temporal subcortical hemorrhage repeatedly occurred 2 months after the second surgery, and the patient died.

CONCLUSIONS

In the present case, primary dural leiomyosarcoma may have invaded the dural sinus and repeated intracranial hemorrhage occurred due to a venous circulatory disturbance. The aggressive clinical course observed is rare. A clearer understanding of the route of invasion and a careful evaluation after primary treatment are needed in order to avoid hemorrhagic complications.

Pazopanib-mediated Long-term Disease Stabilization after Local Recurrence and Distant Metastasis of Primary Intracranial Leiomyosarcoma: A Case Report on the Efficacy of Pazopanib as a Salvage Therapy

Primary intracranial leiomyosarcoma (LMS) is an extremely rare tumor of the central nervous system. Only sporadic case reports have been published, and therefore data regarding long-term prognosis remain scarce. A 76-year-old woman presented with a right parietal mass, which had grown rapidly in the month prior to admission. Neuroimaging showed a resemblance to intraosseous meningioma. Gross total resection of the tumor was achieved, and histological diagnosis confirmed LMS. Because positron emission tomography (PET) with fluorodeoxyglucose (FDG) just after the resection showed no abnormal uptake, we diagnosed the tumor as primary intracranial LMS. Follow-up PET at 16 months after treatment showed two foci of FDG uptake in the bilateral lungs. Histological diagnosis by surgical resection identified the lesions as lung metastases of LMS. In addition, follow-up head magnetic resonance imaging (MRI) at 31 months showed local recurrence, and we conducted salvage therapy using CyberKnife system (Accuray incorporated) and pazopanib. To date, for 15 months after local recurrence, she is alive with intracranial recurrent disease remained inactive.

Primary intracranial leiomyosarcoma in an immunocompetent patient: Case report and review of the literature

Primary leiomyosarcoma is a rare tumor in the CNS, with few reported cases. Here, we describe a case of a primary intracranial leiomyosarcoma of the tentorium cerebelli. A 43-year-old woman presented with headache, acute vision loss, and difficulty speaking. MRI revealed a large heterogeneous-enhancing occipital mass, which was subsequently resected and diagnosed as a primary intracranial leiomyosarcoma. The patient went onto adjuvant radiotherapy delivering 60 Gy in 30 fractions. These tumors are exceedingly rare in immunocompetent individuals. We reviewed the 16 cases that have been reported in the literature. Surgical resection was the most common treatment (92%) with 53% receiving adjuvant radiation. There currently is no standard treatment regimen for intracranial leiomyosarcomas. Additional case reports that include descriptive treatment approaches with patient outcomes may help ascertain the best approach to treating these malignancies.

Primary intracranial dural-based Ewing sarcoma/peripheral primitive neuroectodermal tumor mimicking a meningioma: A rare tumor with review of literature

Ewing sarcoma/peripheral primitive neuroectodermal tumor (ES/pPNET) is a malignant small, round cell tumor arising from bone and soft tissue in children and young adults. It can occur at osseous and extraosseous sites. Its usual locations are diaphysis of long bones followed by pelvis, ribs, vertebrae, and rarely skull. We reviewed the literature and PubMed advanced search on ES/pPNET occurring at extraosseous sites, mainly involving the central nervous system (CNS). We reported a case of a 22-year-old male presenting with seizure finally diagnosed as a case of ES/pPNET. The challenges in management of this rare CNS tumor and its differential diagnosis are highlighted. We found that most cases of ES involving CNS represent secondary metastases from extracranial sites of ES/pPNET and there are rare case reports of primary intracranial ES-pPNET. Furthermore, among these intracranial tumors, most common tumors occupy an intraaxial location and only a handful of cases of dural-based or extraaxial tumors mimicking meningioma are reported. Differentiation of pPNET from central PNET (cPNET) is important as it has definitive therapeutic and prognostic implications. Awareness of this entity of ES/pPNET, its rare dural presentation, and differentiation from the more common cPNET is needed for appropriate patient management. Meningeal ES/pPNET has to be kept in mind in the differential diagnosis of meningeal tumors eroding bone.

Primary intracranial leiomyosarcoma of the torcular Herophili associated with Fanconi anemia and allogenic stem cell transplantation

PURPOSE

Fanconi anemia is associated with a high risk for developing malignant tumors. The occurrence of primary intracranial leiomyosarcoma, however, which in general has a poor prognosis, has not been described thus far. The purpose of this study is to report on management and outcome of leiomyosarcoma of the torcular Herophili associated with Fanconi anemia in a pediatric patient.

CASE REPORT

A 12-year-old girl with Fanconi anemia presented with a primary intracranial leiomyosarcoma arising from the torcular Herophili and infiltrating the adjacent venous sinuses after previous allogenic hematopoietic stem cell transplantation. Radical tumor resection followed by radiotherapy resulted in tumor-free survival and good outcome at a 2-year follow-up.

CONCLUSION

Despite occurrence of leiomyosarcoma in a site thought unfavorable for surgery, combined tumor resection and radiosurgery may yield excellent outcome.

Concurrent occurrence of primary intracranial Epstein-Barr virus-associated leiomyosarcoma and Hodgkin lymphoma in a young adult

Although Epstein-Barr virus (EBV) infection has been known to be associated with a heterogeneous group of malignancies including Hodgkin lymphoma (HL), its association with smooth-muscle tumors (SMTs) has recently been described. Of these SMTs, a primary intracranial EBV-associated leiomyosarcoma (EBV-LMS) is extremely rare, and most of the reported cases were of immunocompromised and/or pediatric patients. A neurologically asymptomatic, previously healthy 27-year-old man was found to have a PET-positive brain lesion during a staging workup for his recently diagnosed HL. Subsequent MRI revealed a 2.6 × 4.0 × 3.3-cm inhomogeneously enhancing tumor with marked surrounding edema in the right anterior frontal lobe. He was serologically HIV negative. He underwent a right frontal lobectomy with gross-total resection of the tumor. Intraoperatively, the tumor had fairly discrete margins and appeared to arise from the anterior falx (that is, it was dural based). Microscopically, the tumor was composed of interlacing fascicles of spindle cells with brisk mitotic activity and multiple foci of necrosis. Immunohistochemically, the tumor cells were positive for caldesmon and smooth-muscle actin and negative for desmin, CD34, CD99, bcl-2, S100 protein, and GFAP. A Ki-67 labeling index was up to 30%. Epstein-Barr virus-encoded RNA in situ hybridization demonstrated strong diffuse positivity with more than 90% of tumor cells staining. Most of the Reed-Sternberg cells in HL were also labeled with Epstein-Barr virus-encoded RNA. This is the first case of a concurrent occurrence of rare intracranial EBV-LMS and HL in a seemingly "immunocompetent" adult patient (immunocompetence determined by routine laboratory data and clinical history). We should be aware of EBV-SMT as a differential diagnosis of dural-based spindle cell neoplasm in this setting given that patients with HL, even at presentation, exhibit a persistent defect in cellular immunity.

Two patients with primary sellar leiomyomas, a rare entity

Leiomyomas are benign smooth muscle tumors commonly found in the genitourinary or gastrointestinal tracts. Rarely, they present as primary intracranial extra-axial brain tumors. Most of these lesions have been described in immunocompromised patients, but have been found very rarely in the immunocompetent patient. We present two patients with sporadic sellar leiomyomas. The first patient is a 25-year-old woman who presented with a 2-year history of amenorrhea and a heterogeneous lesion. The second is a 53-year-old man who presented with headaches and progressive panhypopituitarism, and a large cystic lesion expanding the sella. In both patients, transnasal transphenoidal surgery was performed for resection of the tumor. We review the intraoperative findings, neuropathology and immunohistochemistry and the clinical follow-up. A literature search, which revealed only two prior reported cases of sporadic sellar leiomyomas, and subsequent review led us to conclude that the natural history of sellar leiomyomas relates to the immune status of the patient and that these tumors may cause pituitary dysfunction through infiltration of the gland, mass effect and compression, or even potentially as a byproduct of prolactin secretion intrinsic to the tumor itself. Complete surgical resection of these infiltrating tumors may not be advisable when pituitary function is intact. Long-term endocrine follow-up in these patients is advised.

Sarcomas other than Kaposi sarcoma occurring in immunodeficiency: interpretations from a systematic literature review

PURPOSE OF REVIEW

In immunodeficiency, an increased sarcoma risk is confirmed for Kaposi's sarcoma. Whether rates of other sarcoma subtypes are elevated in the setting of immunodeficiency is not known. We therefore reviewed published case reports on HIV and AIDS patients and organ transplant recipients with sarcomas. For comparison, we assessed sarcomas in the U.S. general population using Surveillance Epidemiology End Results (SEER) data.

RECENT FINDINGS

A total of 176 non-Kaposi sarcoma were identified, 75 in people with HIV and AIDS and 101 in transplant recipients. Leiomyosarcomas (n = 101) were the most frequently reported sarcomas, followed by angiosarcomas (n = 23) and fibrohistiocytic tumors (n = 17). Leiomyosarcomas were reported with two age peaks, in children and young adults. Epstein-Barr virus (EBV) was detected in the tumor cells in 85 and 88% of leiomyosarcomas in HIV-infected people and transplant recipients, respectively. Angiosarcomas and fibrohistiocytic tumors were most frequently reported in men. Among kidney transplant recipients, 20% of sarcomas arose at the site of an arteriovenous fistula. In comparison, leiomyoscarcomas, angiosarcomas, and fibrohistiocytic tumors comprised 16.9, 3.8, and 18.7% of sarcomas in the U.S. general population.

SUMMARY

Leiomyosarcoma and angiosarcoma may occur disproportionately in immunodeficiency. Leiomyosarcomas appear causatively linked to EBV, whereas angiosarcomas might be correlated with an arteriovenous fistula. Additional studies are necessary to understand the contribution of immunodeficiency to the cause of these sarcomas.

Primary intracranial leiomyosarcoma: review of the literature and presentation of a case

BACKGROUND

Primary intracranial leiomyosarcoma (LMS) is a rare tumor of the central nervous system and therefore has only been reported sporadically.

METHODS

The MEDLINE database was searched for relevant case reports and series published in English from 1969 to March 2012. These papers were reviewed to identify clinical and histopathological features, treatment modalities, and prognoses of patients with primary intracranial LMS.

RESULTS

We reviewed 37 patients, including our patient, with primary intracranial LMS. Of these cases, 16 (43.2%) involved immunosuppression, 4 (10.8%) involved radiation-induced LMS, 3 (8.1%) cases involved a potential leiomyosarcomatous transformation of a brain lesion, and 7 (18.9%) cases, including the presented case, had no specific medical history. The treatment for these cases included resection (33/37, 89.2%), postoperative radiotherapy (20/37, 54.1%), and chemotherapy (7/37, 18.9%).

CONCLUSIONS

The best method for the treatment of LMS could not be determined due to the limited number of cases that have been reported. However, optimized surgical resection, postoperative radiotherapy, and sarcoma-based chemotherapy may improve treatment outcomes.

Meningeal tumors histologically mimicking meningioma

A number of meningeal neoplastic lesions may radiologically and clinically simulate meningioma. In the present paper, we review meningeal non-meningothelial tumors which may also mimic different histotypes of meningioma at the histological examination. Awareness that these lesions exist may facilitate their recognition and correct diagnosis, which is of fundamental importance for prognosis and an appropriate therapeutic approach. Histological and immunohistochemical clues for the differential diagnosis are discussed.

Epstein-Barr virus-associated leiomyosarcoma with cutaneous involvement in an African child with human immunodeficiency virus: a case report and review of the literature

Epstein-Barr virus (EBV)-associated smooth muscle tumors (SMTs) are infrequently encountered lesions restricted to immunocompromised patients. However, they represent the second most common tumor in children with human immunodeficiency virus (HIV) infection. We report a case of a progressively enlarging abdominal mass with cutaneous involvement in an HIV-infected, 4-year-old African girl in Malawi with clinical acquired immunodeficiency syndrome on highly active antiretroviral therapy. Analysis of an excisional specimen revealed a well-differentiated leiomyosarcoma and subsequent studies revealed diffuse nuclear positivity for Epstein-Barr virus early RNAs in lesional cells. We present a report of this case and provide a summary of the literature regarding SMTs in pediatric HIV-infected patients. In addition, we draw attention to the cutaneous manifestations of SMTs in immunosuppressed populations. We highlight EBV-related SMTs as a potential cutaneous complication of HIV infection in children and immunosuppressed patients populations as a whole.

Malignant Peripheral Nerve Sheath Tumor of the Vestibulocochlear Nerve and Brainstem

BACKGROUND AND IMPORTANCE

Malignant peripheral nerve sheath tumors are the most common malignant mesenchymal tumors of soft tissues, but they are very rare when found to arise from a cranial nerve and when not in association with neurofibromatosis. These tumors are highly malignant and carry a poor prognosis with survival usually less than 6 months.

CLINICAL PRESENTATION

The authors report the case of a 23-year-old female with no history of phakomatoses, previous irradiation, or known genetic disorders, who presented with a malignant peripheral nerve sheath tumor of the vestibulocochlear nerve and brainstem. Multiple staged skull base approaches were carried out with maximal possible resection. Adjunctive therapies including standard radiation therapy, intensity-modulated radiation therapy, and stereotactic gamma knife radiosurgery were used with an ultimate patient survival of 27 months.

CONCLUSION

To our knowledge, this is the first report describing a patient with a malignant peripheral nerve sheath tumor of the vestibulocochlear nerve and brainstem treated with staged surgical approaches in conjunction with multiple forms of radiotherapy and having a significant survival of more than 2 years.

Epstein-Barr virus-associated adrenal smooth muscle tumors and disseminated diffuse large B-cell lymphoma in a child with common variable immunodeficiency: a case report and review of the literature

This article reports the clinical and the histological features in a 7-year-old girl affected by common variable immunodeficiency (CVID) who developed multiple Epstein-Barr virus-associated tumors, represented by bilateral adrenal smooth muscle tumors (EBV-SMT) and multifocal diffuse large B-cell lymphoma. The EBV-SMTs showed features compatible with a benign or at least a low-malignant potential neoplasm. A peculiar feature observed in both EBV-SMTs was the occurrence of numerous lymphocytes intermingled with the spindle cells, which consisted of CD3+ CD5+ T-cells, with a predominant cytotoxic CD8+ component. Interestingly, EBV status differed in the neoplasms, since the EBV-SMTs were negative for LMP1 and positive for EBER, whereas the B-cell lymphoma expressed both EBV markers. Furthermore, EBV-LMP1 deletion was positive only in the EBV-SMTs, thus indicating that these tumors were the consequence of 2 distinct, EBV-dependent transformations. Similarly, lymphocyte clonality assay also showed different clonal bands in different sites (skin and nasal cavity), suggesting the development of intratumoral mutations. Finally, the authors review all 127 previously reported EBV-SMT, with discussion of their clinical and pathological features.

AIDS-Related EBV-Associated Smooth Muscle Tumors: A Review of 64 Published Cases

The number of reported cases of smooth muscle tumor (SMT) arising in patients with AIDS has been increasing since the mid-1990s. The aim of this study is to characterize the epidemiology, clinical manifestations, pathologic features, prognosis and, management of Epstein-Barr virus-related SMT (EBV-SMT) in patients with AIDS. An English language literature search identified 53 articles including 64 reported cases of EBV-SMT. The majority of these reports involved patients who were young, severely immunosuppressed, and had multifocal tumors. The central nervous system was the most common site to be involved. Histologically, tumors had smooth muscle features and were immunoreactive for muscle markers and all but two tumors demonstrated the presence of EBV by either immunohistochemistry, in situ hybridization, and/or PCR. While mitoses and/or necrosis were used to separate leiomyoma from leiomyosarcoma, these features did not correlate with clinical outcome. Treatment included primarily resection, and less often radiotherapy, chemotherapy and highly active antiretroviral therapy (HAART). Overall, EBV-SMTs appear to have variable aggressiveness and clinical outcome and may exhibit a more favorable prognosis compared to conventional leiomyosarcoma. Tumor-related death from EBV-SMT occurred in only 4 of 51 patients.

Primary intracranial leiomyosarcoma in an immunocompetent patient: case report

We report a case of intracranial leiomyosarcoma (LMS) arising after resection of neurofibroma at the cerebellopontine angle. A 45-year-old immunocompetent woman presented with recurrence of a tumor 9 years after resection performed in another hospital. Magnetic resonance imaging demonstrated a heterogeneously enhancing, dura-based mass at the left cerebellopontine angle. The tumor was subtotally removed via lateral suboccipital craniotomy. LMS was diagnosed based on histological and immunohistochemical findings. Postoperatively, although the patient was treated using local radiotherapy, she died due to rapid regrowth of the tumor. Reevaluation of the specimen obtained in the first operation led to a diagnosis of neurofibroma. Both LMS and neurofibroma rarely occur intracranially. LMS is generally thought to arise from smooth muscle cells of the blood vessels or pluripotent mesenchymal cells. In this case, LMS might also have originated from smooth muscle cells of the vessels in the neurofibroma, possibly associated with mechanical and/or heat stimulation during the previous surgery.

Epstein-Barr virus associated primary intracranial leiomyoma in organ transplant recipient: case report and review of the literature

INTRODUCTION

A 45 year old female renal transplant recipient presented with headaches of 3 months duration. Clinical and radiological evaluation revealed an approximately 4x4 cm rounded, enhancing mass at the left temporal pole. At surgery, the mass had dural attachment and clinically, radiographically, and macroscopically resembled a meningioma. Histopathological analysis revealed a leiomyoma. Epstein-Barr virus (EBV) DNA was demonstrated within the tumour cell nuclei by the in situ hybridisation technique.

DISCUSSION

This is the first documentation of an EBV-associated primary intracranial leiomyoma in an organ transplant recipient and provides additional evidence of a possible relation between EBV infection and development of smooth-muscle tumours (SMT).

CONCLUSION

With increasing numbers of individuals being on long-term immuno-suppression, EBV-associated SMTs may be encountered more frequently in the future.

Primary intracranial leiomyomas: Report of two cases and review of the literature

A leiomyoma is a benign neoplasm composed of smooth muscle cells that commonly occurs in the genitourinary and gastrointestinal tracts. Primary intracranial leiomyoma, however, is extremely rare and only a few cases have been reported to date. In this study, we present two cases of primary intracranial leiomyomas in middle-aged men. Magnetic resonance images (MRI) showed lesions with homogeneous low signals on T1-, T2-, diffusion-weighted, and FLAIR sequences. Tumors were totally removed and there was no evidence of recurrence in the follow-up study. Pathological analysis with immunohistochemistry revealed that tumors had characteristics of benign smooth muscles. A review of relevant literature has been conducted.

Cerebral tumor with extensive rhabdoid features and a favorable prognosis

This 32-year-old woman, 27 weeks pregnant, harbored a cystic mass with a solid component in the left frontal lobe. Histologically, the lesion was hypercellular and contained a diffuse sheet of eosinophilic cells of various sizes. The cells were almost round and had a few prominent, eccentrically placed, hyperchromatic nuclei of various sizes. Immunohistochemically, the tumor was reactive for vimentin, epithelial membrane antigen, cytokeratin AE1/AE3, smooth muscle actin, and BAF47/INI-1, and negative for glial fibrillary acidic protein, neurofilament protein, S100 protein, CK7, CK20, HMB-45, MIC2, and Bcl-2. The Ki 67 labeling index was 4.2%. Comparative genomic hybridization analysis revealed aberrations of the chromosomal copy number of +7 and −10. This tumor could not be categorized according to the present World Health Organization classification. Results of staining with glial fibrillary acidic protein were not consistent with a glioma, and staining with INI-1 was inconsistent with atypical teratoid/rhabdoid tumor. The tumor was therefore designated as a “cerebral tumor with extensive rhabdoid features.”

Malignant peripheral nerve sheath tumors of cranial nerves and intracranial contents: a clinicopathologic study of 17 cases

Malignant peripheral nerve sheath tumors (MPNSTs) arising from cranial nerves or their branches are very uncommon. The literature consists mainly of isolated case reports and small series. We identified 17 such cases in 14 males and 3 females. With one exception, the tumors affected adults (age range 5 to 69 y, mean 39, median 32). Sites of involvement included vestibular nerves (n=6), vagal nerves (n=4), facial nerves (n=3) (1 centered in the geniculate ganglion), and 2 unspecified cranial nerves in the posterior fossa. In addition, 1 tumor involved the optic chiasm (n=1). Only 1 tumor arose in brain parenchyma of (frontal lobe). All but 3 lesions were intracranial. Five tumors arose in patients who satisfied clinical criteria for neurofibromatosis type 1 (NF1). One patient with a vestibular tumor and presumed NF2 had previously undergone resection of a contralateral vestibular cellular schwannoma. One posterior fossa tumor was a malignant melanotic schwannoma. Four patients had postirradiation malignant peripheral nerve sheath tumors, 2 having been treated for optic chiasm glioma, both being NF1 affected. One patient was irradiated for hypothalamic pilocytic astrocytoma and another for cervical Hodgkin disease. Identifiable precursor lesions included schwannoma (n=4), plexiform neurofibroma (n=2), and solitary intraneural neurofibroma (n=2). All tumors were histologically high grade (6 grade III and 10 grade IV). Three tumors showed heterologous elements, 2 osseous, and 1 rhabdomyoblastic. More often scattered than diffuse, S-100 protein staining was noted in 11 of 16 tumors and variable collagen IV staining in 10 of the 16. Immunoreactivity for p53 protein was diffuse and strong in 7 of 11 tumors. Twelve patients died within 17 months to 3 years of diagnosis, 1 was lost to follow-up, 2 are very recent cases, and 2 patients are currently alive, 1 after 2 recurrences, and another with spinal leptomeningeal metastases. Malignant cranial nerve sheath tumors are rare and are associated with the same poor prognosis as those of spinal nerves at other sites.

Primary intracranial dural-based synovial sarcoma with an unusual SYT fluorescence in situ hybridization pattern

The authors present the case of an elderly man with a primary dural-based intracranial synovial sarcoma. Histological and immunohistochemical profiles of the lesion were diagnostic for a synovial sarcoma, and molecular studies using fluorescence in situ hybridization were compatible with a synovial sarcoma. A wide array of spindle cell neoplasms has been described as originating in the dura. To the authors' knowledge, however, this is only the second primary durabased intracranial synovial sarcoma ever reported, emphasizing the importance of a broad differential diagnosis when encountering spindle cell lesions of the meninges.

Synovial sarcoma of the neck in a child: a multidisciplinary approach

Synovial sarcoma (SS) is the most common nonrhabdomyosarcomatous soft tissue sarcoma in childhood, but the head-neck site accounts for less than 5% of cases. The authors report a 10-year-old boy with SYT-SSX1 positive left parapharyngeal SS, resistant to front-line VAIA chemotherapy, who obtained a good partial response by salvage regimen (I(3)VE + CEV + I(3)VE) and local radiotherapy, so a complete surgical resection could be performed. The complete remission was subsequently consolidated by ablative high-dose chemotherapy, followed by autologous stem cell reinfusion. The child remains in complete remission at 36 months after completion of treatment.

Intracranial Primary Synovial Sarcoma: Radiologic-Pathologic Correlation

We present a very rare case of spontaneous intracranial synovial sarcoma. A 15-year-old female was admitted to our institution for a cervical spine MRI, reporting a gradual pain of the dorsal neck after an injury three months previously. After obtaining the first sequence we discovered a large skull base mass. We immediately performed a skull base MRI. MR arteriography, MR venography, CT and DSA were also performed. A large space-occupying lesion was demonstrated, extending from the right petrous bone to the occipital bone at the level of the foramen magnum and the right atlantooccipital junction. CT revealed calcifications. The MR venography demonstrated diminished flow in the right transverse and sigmoid sinus, as well in the right internal jugular vein. Otorhinolaryngological evaluation revealed a slight ipsilateral conductive hearing loss. The whole mass was macroscopically removed via a retrosigmoid, transmastoid, infratemporal approach. Postoperative course was uneventful, except for complete palsy of the ipsilateral hypoglossal nerve. The final pathological examination including immunohistochemical picture, showed findings consistent with synovial sarcoma (monophasic spindle-cell type).

Cryptococcal Inflammatory Pseudotumors

"Inflammatory pseudotumors" (IPTs) embrace a heterogeneous spectrum of reactive, infective, and neoplastic entities, that are characterized by a clinical mass composed of a histologic proliferation of spindle cells in a background of inflammatory cells and collagen fibers. Although a spectrum of microorganisms have been identified in infective IPTs, mycobacterial infective IPTs are reported most commonly. We document 5 solitary cryptococcal IPTs, in 2 males and 3 females, aged 19 to 43 years, in the soft tissues of the anterior chest wall, thigh, and arm. All were HIV-positive and had been treated for disseminated cutaneous and/or meningeal cryptococcosis with antifungal therapy, 6 to 12 months earlier. The specimens demonstrated a storiform arrangement of plump spindle cells, in addition to spindle and polygonal cells that were arranged in a haphazard manner. Background lymphocytes, plasma cells, and fibrosis were noted, in addition to scattered giant cells and focal necrosis. On high-power examination, Cryptococcus neoformans yeasts were identified within and between vacuolated spindle and polygonal cells on routine and special stains, confirming cryptococcal IPTs. Immunophenotyping of the spindle cells confirmed a mixed histiocytic and myofibroblastic lineage, with a predominance of the former. In documenting 5, hitherto unreported, pseudotumoral spindle cell reactions to C. neoformans, we not only highlight the need for intense appraisal of all IPTs for infective agents on routine and special stains and investigations, but also postulate that a complex host-fungus interaction, coupled with an exuberant, myofibroblastic response to incomplete therapy, are the pathogenetic drive for the pseudotumoral presentation.

Synovial sarcoma of the sellar region

Primary sarcomas of the sellar region are uncommon, although a wide variety have been reported. To date, no cases of primary synovial sarcoma have been described as occurring at this site. We report an immunohistochemically and molecular genetically confirmed primary synovial sarcoma involving the sellar/parasellar region and cavernous sinus in an adult male. Subtotal resection and radiosurgery proved to be efficacious. The spectrum of primary sellar region sarcomas is summarized.

Malignant Myoepithelioma of Cranial Dura

Malignant tumors of myoepithelial origin have been increasingly recognized at a variety of sites. Herein, we describe an example of malignant myoepithelioma arising in intracranial dura. The patient is a 47-year-old woman who presented with intracranial hemorrhage and on magnetic resonance imaging was found to have an enhancing tumor. No extracranial primary tumor was identified. A gross total resection was performed. Histologically, it varied in pattern from diffuse to focally (<10%) ductular and consisted of epitheloid to spindle cells showing marked mitotic activity. Prominent infiltration of the dura was noted. Immunohistochemical stains showed convincing expression of cytokeratins (AE1/AE3 and CAM 5.2), S-100 protein, smooth muscle actin, and glial fibrillary acidic protein. Electron microscopy performed on formalin-fixed, paraffin-embedded tissue demonstrated cohesive cells with focal intermediate filament content and surface basal lamina formation at stromal interfaces. Occasional desmosomes with tonofilaments surrounded intercellular lumina containing masses of filamentous material. This example of malignant myoepithelioma is the first convincing primary salivary gland type tumor to arise in an intracranial location outside the sellar region or ear. Intracranial dura should be added to various sites at which this morphologically heterogenous tumor may arise.

Follicular Lymphoma of the Dura

OBJECTIVE:

We present an unusual dural-based follicular lymphoma with radiological and macroscopic features similar to a meningioma. The unusual location of this tumor and its distinction from meningioma, mucosa-associated lymphoid tissue-type marginal zone B-cell lymphoma of the dura, and intraparenchymal central nervous system lymphoma, dramatically alters the patient's postoperative treatment. The case illustrates the clinical, radiological, and histological relevance of this rare entity.

CLINICAL PRESENTATION:

A 41-year-old Caucasian man with chronic bifrontal headaches and a raised area over his left frontal cranium that persisted for 1 year presented to the emergency room with nausea and vomiting. His family reported that the patient demonstrated increased irritability and aggressive behavior. A computed tomographic scan revealed a large mass of the left frontal convexity with edema and mass effect. Magnetic resonance imaging scans showed a 5-cm homogeneously enhancing mass in the left posterior frontal lobe.

INTERVENTION:

Preoperatively, the patient underwent angiography and embolization of the tumor. The patient underwent gross total resection of tumor. The dural-based tumor invaded the cranium and scalp. Neuropathological findings were consistent with low-grade follicular lymphoma. The patient is currently undergoing radiation and chemotherapy.

CONCLUSION:

The current case represents the first report of extensive intracranial dural involvement by a follicular lymphoma that shows a classic immunophenotype by immunohistochemistry and flow cytometry. The case illustrates the clinical and radiographic similarities between dural-based lymphoma and meningioma. Distinguishing dural-based follicular lymphoma from mucosa-associated lymphoid tissue-type lymphoma and from intraparenchymal primary central nervous system lymphomas, which are more often large cell lymphomas with more aggressive biological behavior, is essential for proper clinical management.