An intracranial malignant solitary fibrous tumor

Intracranial solitary fibrous tumor mimicking meningioma: A case report

RATIONALE

Solitary fibrous tumor is a rare mesenchymal tumor. This case report describes the diagnosis and treatment of this tumor.

PATIENT CONCERNS

A 31-year-old patient presented with epileptic seizure and headache 1 day prior to the visit and showed transient right limb hemiplegia for 6 hours that was resolved after intravenous infusion of mannitol.

DIAGNOSES

Based on imaging, the provisional diagnosis was meningioma. Postsurgical histopathological diagnosis confirmed solitary fibrous tumor.

INTERVENTIONS

The lesion was totally excised. The patient improved remarkably after the operation, without any signs of associated limb movement disorder. No epileptic seizure was observed or reported after the operation.

OUTCOMES

Postoperation computed tomography (CT) scans showed no obvious residual tumor. The patient was followed up every 3 months for a total of 1 year following the operation, during which time the patient did not complain of headache or seizure.

LESSONS

The manifestation of solitary fibrous tumor (SFT) through imaging methods has certain specific findings,butimmunohistochemistry is still very important for confirming the diagnosis.

Rapid recurrence and bilateral lungs, multiple bone metastasis of malignant solitary fibrous tumor of the right occipital lobe: report of a case and review

BACKGROUND

Intracranial malignant solitary fibrous tumor (MSFT) is extremely rare. The authors report a case of MSFT of the right occipital lobe with a rapid recurrence and bilateral lung, multiple bone metastasis.

CASE PRESENTATION

The patient was a 25-year-old male presenting with headache, nausea and visual disturbances without obvious cause. Three times right-side occipital craniotomies were performed and two times postoperative conformal radiotherapy were administered within one year. 4 months after the third time of right-side occipital craniotomy, the patient felt right chest pain and neck pain. Positron emission tomography/computed tomography (PET/CT) showed tumor recurrence of the right occipital lobe and bilateral lung metastasis, multiple bone metastasis including: vertebrae, libs, the left iliac wing, sacrum, the right ischium and upper parts of both femurs. Ultrasound guided puncture biopsy of left-side back of the neck and CT guided puncture biopsy of the third lumbar vertebra were performed. General sample showed grayish white or grayish red with irregular shape. Histopathologically, the tumor was composed of areas of alternating hypercellularity and hypocellularity with spindle-shaped cells, which arranged as fascicular, storiform pattern or patternless pattern, with intervening irregular eosinophilic collagen bundles. Some areas showed hemangiopericytoma-like perivascular pattern and perivascular hyalinization. Tumor cells were pleomorphic with mitotic counts of more than 4 per 10 high power fields and showed coagulative necrosis. Immunohistochemically, tumor cells were diffusely positive for vimentin and CD99, focal positive for CD34, bcl-2 and Actin. Ki-67 labelling index was more than 40%. The final pathological diagnosis was MSFT of the right occipital lobe, metastatic MSFT of left-side back of the neck and the third lumbar vertebra.

CONCLUSION

The MSFT of the right occipital lobe with recurrence and bilateral lung, multiple bone metastasis is extremely rare. Although intracranial MSFT is extremely rare, it should be considered in the differential diagnosis. Definite diagnosis depended mainly on pathological morphology and immunohistochemistry. The prognosis of MSFT is poor due to recurrence and metastasis. Complete resection of intracranial MSFT is difficult, and carful follow-up is needed.

Solitary fibrous tumor of the central nervous system: a clinicopathologic study of 24 cases

OBJECTIVE

Solitary fibrous tumor is a rare, spindle-cell benign mesenchymal neoplasm and has a high recurrence rate. In this study, we reviewed our experience in the diagnosis and treatment of 24 patients with central nervous system solitary fibrous tumors.

METHODS

Clinical data were retrieved from the medical records. Prognosis was assessed by clinic service and telephone interview. The specimens were stained with hematoxylin and eosin. Immunohistochemistry for CD34, CD99, EMA, HMB-45, Bcl-2, vimentin, GFAP, S-100, MBP, CK and MIB-1 was performed in all cases. Distributions of time to progression and recurrence were estimated using the Kaplan-Meier method and compared using the log-rank test.

RESULTS

The 24 patients included 13 men and 11 women with a median age of 49.0 years. The most frequent initial symptoms were headache, dizziness, unstable walk and hearing loss. The most common location was cerebellar pontine angle (n = 6). Surgery reached gross total removal for 18 patients but subtotal removal for six patients on initial operation. Histopathologic examination showed spindle to oval cells were disposed in wavy fascicles between prominent, eosinophilic bands of collagen. Dense bands of collagen appeared in cross section as minute nodules that separated individual tumor cells. Cellular areas with a partial hemangiopericytoma pattern were noted in six cases. Atypical presentations were shown on initial operation in three cases. CD34, CD99 and vimentin were 100% positive; but EMA, CK, MBP, HBM-45 and GRAP were 100% negative. The positive in Bcl-2, RF and S-100 was 89%, 85% and 26%, respectively. Follow-up information was available for 23 patients. The median follow-up period was 36.0 months. Nine patients recurred and one patient died from the progression. Incomplete surgical resection was significantly associated with recurrence (p = 0.010). MIB-1 labeling index in recurrence was higher than in no recurrence (6.0% versus 3.4%, p = 0.029). All treated with subtotal removal only had subsequent tumor recurrence or progression; however, the two patients who were administered adjuvant radiosurgery after subtotal removal did not recur or progress. Adjuvant radiosurgery seemed to improve the prognosis (p = 0.028).

CONCLUSIONS

Solitary fibrous tumor is a rare mesenchymal tumor with a propensity to recur. The most affected area is the cerebellopontine angle. Immunohistochemistry should be used to differentiate solitary fibrous tumor from other tumors. The extent of resection, MIB-1 labeling index and some anaplastic features might be predictive for recurrence. Postoperative radiosurgery might be an option in incompletely resected solitary fibrous tumor. Regular and long-term follow-up remains mandatory to monitor recurrence.

Solitary fibrous tumors and hemangiopericytomas of the meninges: overlapping pathological features and common prognostic factors suggest the same spectrum of tumors

Meningeal solitary fibrous tumors (SFTs) and hemangiopericytomas (HPCs) are distinct entities in the World Health Organization (WHO) classification of central nervous system (CNS) tumors while they belong to the same spectrum of tumors in other locations. Well-defined histological prognostic factors are also lacking for these tumors. In order to clarify the relationship between SFT and HPC and to find histological and immunohistochemical prognostic factors, we carried out a retrospective study in 89 patients. The following histological parameters were recorded: hypercellularity, collagenic areas, cytonuclear atypias, necrosis, mitotic count per 10 high-power fields, vasculo-nervous adherences defined by engulfment of vessel or nerve by the tumor, brain infiltration. We found overlapping histological and immunohistochemical features between SFT and HPC. The most relevant histological prognostic factors in the whole cohort for both progression-free survival (PFS) and overall survival (OS) in univariate analysis were hypercellularity, high mitotic count (>5 per 10 high-power fields) and necrosis. On the basis of these results, we propose a new grading scheme for these tumors which was of pronostic value for both PFS and OS in uni- and multivariate analysis. As extent of surgery was also a prognostic factor for both PFS and OS in univariate analysis, we propose that management of SFT/HPC might be based both on quality of removal and histological grade.

Solitary fibrous tumor of the central nervous system: a 15-year literature survey of 220 cases (August 1996-July 2011)

We reviewed the world literature on solitary fibrous tumors of the central nervous system from August 1996 to July 2011, focusing on both clinicopathological features and diagnostic findings. The anatomical distribution of the 220 cases reported so far reveals that most are intracranial and just over one-fifth are intraspinal. In decreasing frequency, intracranial tumors involve the supratentorial and infratentorial compartments, the pontocerebellar angle, the sellar and parasellar regions, and the cranial nerves. Intraspinal tumors are mainly located in the thoracic and cervical segments. Although most solitary fibrous tumors of the central nervous system are dural based, a small subset presents as subpial, intraparenchymal, intraventricular, or as tumors involving the nerve rootlets with no dural connection. Preoperative imaging and intraoperative findings suggest meningioma, schwannoma or neurofibroma, hemangiopericytoma, or pituitary tumors. Immunohistochemistry is critical to establish a definitive histopathological diagnosis. Vimentin, CD34, BCL2, and CD99 are the most consistently positive markers. The usual histologic type generally behaves in a benign manner if complete removal is achieved. Recurrence is anticipated when resection is subtotal or when the tumor exhibits atypical histology. The proliferative index as assessed by MIB1 labeling is of prognostic significance. Occasionally, tumors featuring conventional morphology may recur, perhaps because of minimal residual disease left behind during surgical extirpation. Rare extracranial metastases and tumor-related deaths are on record. Surgery is the treatment of choice. Stereotactic and external beam radiation therapy may be indicated for postsurgical tumor remnants and for unresectable recurrences. Long-term active surveillance of the patients is mandatory.

Solitary Fibrous Tumor of the Central Nervous System

Solitary fibrous tumor (SFT) of the central nervous system was first described in 1996. A number of cases have been reported since. The authors present 5 new cases: 4 intracranial and 1 intraspinal. All patients were adults (age range, 47 to 75 years); 4 were male and 1 female; 4 cases were primary tumors; and 1 was a second tumor recurrence. All patients were surgically treated with gross total removal. All cases were histologically examined with immunohistochemical confirmation; 2 tumors exhibited diffuse classic histology, 1 tumor was a cellular variant, 1 tumor was myxoid, and 1 was predominantly classic with focal myxoid features and focally pleomorphic. The postoperative course was uneventful in all. The patient with the cellular variant experienced 2 local recurrences and eventually died of disease 10 years after the initial diagnosis. The patient with the myxoid variant—the tumor studied—which was the second recurrence of a previously misdiagnosed fibrous meningioma surgically treated 15 years earlier, had a recurrence after 2 years for the third time and eventually died of disease. Three patients are alive and well 11.6, 6, and 4 years after surgery. SFT is a rare tumor that needs to be differentiated from some mimickers, mainly fibrous meningioma, hemangiopericytoma, and with regard to the myxoid variant, also adult-onset myxochordoid meningioma and myxoid peripheral nerve sheath tumor. Immunohistochemistry is crucial for the correct diagnosis of SFT. The authors also performed a review of the literature and found a little more than 200 cases on record.