Surgical Management of Craniospinal Axis Solitary Fibrous Tumors: A Single-Institution Case Series and Comprehensive Review of the Literature

Recurrence of Solitary Fibrous Tumor in the Spinal Cord Following Gross Total and Subtotal Resection: A Case Report of Recurrence 19 Years of Post-total Resection and Systematic Literature Review

Spinal cord solitary fibrous tumors (SFTs), previously known as hemangiopericytoma (HPC), represent exceedingly rare neoplasms. Strategies for their management, such as appropriate follow-up duration, remain controversial due to their propensity for recurrence despite extended periods of quiescence. We report a 51-year-old male presenting with new-onset back pain and gait disturbances, who had undergone gross total resection (GTR) of an SFT within the thoracic spinal cord 19 years ago. Magnetic resonance imaging of the thoracic spine revealed recurrent tumors at the T7 level within the spinal cord. Subsequent resection achieved GTR. A comprehensive literature review was undertaken to assess the benefits of different resection extents (gross total removal (GTR) vs. subtotal removal (STR)), adjuvant radiation therapy, and the optimal duration of postoperative follow-up. Since 1960, 46 cases, including the present one, have reported recurrent spinal SFT/HPC following GTR and STR. Statistical analyses demonstrated that neither the type of resection nor adjuvant radiation therapy significantly impacted median recurrence-free survival in this cohort. Given their unpredictable behavior, meticulous lifelong follow-up following successful resection appears crucial for managing these tumors effectively.

Central nervous system solitary fibrous tumors: Case series in accordance with the WHO 2021 reclassification. Framework for patient surveillance

PURPOSE

Solitary fibrous tumors (SFTs) are a rare type of mesenchymal tumors. The World Health Organization reclassified SFTs in 2021. Currently, guidelines concerning treatment and follow-up are lacking. We performed a retrospective case series with reclassification of SFTs, according to the most recent WHO classification, to explore tumor-behavior. The purpose is to build a framework for long-term patient surveillance.

METHODOLOGY

A retrospective case study was performed according to the PROCESS guidelines. Inclusion criteria were: patients operated on between 2013 and 2023 in two neurosurgical centers with the diagnosis of 'hemangiopericytoma' or SFT on histopathological stains. Patients were excluded if the original stains of the primary tumor were unavailable. The following demographic, radiologic and therapeutic parameters were included in the review: age, sex, original and reclassified anatomopathological diagnosis, location, extent of resection, use of postoperative radiotherapy, location of and time to recurrence, location of-and time to metastasis, and survival. Histological material was re-examined by experienced neuropathologists.

RESULTS

Ten patients were identified with a solitary fibrous tumor of the central nervous system (CNS) (three females) between 2013 and 2023. Age at diagnosis ranged from 38 up to 81. Eight patients were treated by gross total resection (GTR) and postoperative radiotherapy (RT) was applied in five cases. Initial WHO grading consisted of three grade I, two grade II, and six grade III lesions. Reclassification according to the WHO 2021 classification of CNS tumors resulted in seven reclassifications, all towards a lower grade. Four patients showed local recurrence, six to eight years after diagnosis, and five patients developed systemic metastases, nine to 13 years after diagnosis.

DISCUSSION

Although rare, SFT should be included in the differential diagnosis of intracranial tumors with extra-axial growth patterns. The current histological grade according to the WHO 2021 does not seem to account for local recurrence rate or systemic metastasis. When a solitary fibrous tumor is presumed, gross total resection is the recommended treatment. Lifelong patient follow-up is necessary due to the risk of delayed recurrence and distant metastasis, even after gross-total resection. We would advocate for the use of CT thorax-abdomen or full body PET in the detection of systemic metastases at diagnosis and during follow-up, however optimal intervals remain unclear.

Intracranial Solitary Fibrous Tumor: A Case of a 21-Year-Old Male With Olfactory Hallucination

Meningeal solitary fibrous tumors (SFTs) are a rare central nervous system neoplastic process, resulting in frequent misdiagnosis as meningioma prior to pathologic analysis. Appropriate diagnosis is essential to lowering morbidity and mortality, as Grade II or III SFTs are aggressive neoplasms that possess metastatic potential. The existing data may suggest that intracranial SFTs primarily afflict those in their fourth through sixth decades of life. However, we present the case of a patient outside this demographic presenting with symptoms that we were unable to identify in any prior reports. A 21-year-old male in the United States Navy presented to the emergency department (ED) with a two-month history of progressive headaches, leading to nausea and emesis. The patient also endorsed a daily incidence of the same olfactory hallucination followed by several minutes of palpitations, flushing, and dizziness. His neurologic exam was unremarkable, but imaging in the ED revealed a large mass abutting the right medial sphenoid wing. The radiographic appearance of the mass with a dural tail led to a preoperative diagnosis of meningioma. However, pathologic analysis following gross total resection identified the mass as an SFT. A brief literature review complementary to this case underscored the high variability of intracranial SFT case presentations with a relative scarcity of epidemiologic data due to rarity. This review identified that it was common to initially diagnose SFTs as meningioma, similar to this particular case. This emphasizes the importance of an appropriate pathologic diagnosis. This case adds to the existing literature as anecdotal evidence of SFT occurring in a young patient and a unique symptom profile most notable for olfactory hallucination and dysautonomia as features of focal seizure.