Intracranial solitary fibrous tumor/hemangiopericytomas: a clinical analysis of a series of 17 patients

OBJECTIVE

Solitary fibrous tumors (SFTs) and haemangiopericytomas (HPCs) are rare mesenchymal tumors in central nervous system (CNS). Although progressed recognition to the diagnosis and treatment of SFT/HPCs, it still remains many confusions regarding on its occurrence, aggressive evolution, malignant transformation, dedifferentiation phenomenon, distant metastasis and unpredictable propensity.

PATIENTS AND METHODS

Seventeen cases of CNS SFT/HPCs who underwent surgical treatment from January 2010 to December 2020 were collected in the authors' institute. Clinical, radiological, pathological data and followup details were reviewed in all cases.

RESULTS

The age of this series was 41-73 years old. Seven cases located subtentorially, five cases originated from middle skull base and four in supratentorial. MRI shows iso-signal intensity on T1WI, and heterogeneous slightly long/short signal on T2WI. There is significant contrast after gadolinium-enhancement. It is easy to be misdiagnosed before surgery. The positive rate of nuclear STAT6 is 94.12%, higher than CD34 (87.5%). Eight patients were grade I, eight grade II and one in grade III. Five cases developed tumor relapse, in which two cases had local intracranial recurrence combined with dissemination and metastasis of cerebrospinal fluid in the spinal canal, accompanied by pathological malignant transformation, and another one occurred blood metastasis.

CONCLUSIONS

CNS SFT/HPCs are rare intracranial tumors with unpredictable propensity. Gross total resection is critical to its overall clinical prognosis. Given its potential recurrence and malignant transition, adjuvant radiotherapies are recommended when necessary, and long-term follow-up is indispensable. The underlying molecular biological mechanisms are still needed to be further exploration.

Doege-Potter syndrome associated to metastatic solitary fibrous tumor

Solitary fibrous tumor (SFT) is a rare fibroblastic mesenchymal neoplasm with an estimated annual incidence of 0.35 per 100,000 individuals. Doege-Potter syndrome is a paraneoplastic syndrome related to solitary fibrous tumor clinically characterized by hypoglycemia, occurring in less than 5% of cases. Herein, we report a case of metastatic SFT associated with recurrent severe hypoglycemia. A 43-year-old male with a noncontributory medical history presented with a painless and progressive growing mass in the right thigh. The histological evaluation rendered the diagnosis of SFT, and tumor resection was performed. One year after the operation, on the oncological follow-up, he was admitted to the emergency unit, manifesting an early-morning seizure associated with a severe hypoglycemia. The laboratory findings of non-islet cell tumor hypoglycemia (NICTH) in the background of a relapsed metastatic solitary fibrous tumor were consistent with the diagnosis of Doege-Potter syndrome. Hepatic embolization associated with oral glucocorticoid was an efficient palliative treatment to control the hypoglycemic crisis and allow hospital discharge.