Xiao-hui Ren, Chun Chu, Chun Zeng, Yong-ji Tian, Zhen-yu Ma, Kai Tang, Lan-bing Yu, Xiang-li Cui, Zhong-cheng Wang and Song Lin
Intracranial epidermoid cysts are rare, potentially curable, benign lesions that are sometimes associated with severe postoperative complications, including hemorrhage. Delayed hemorrhage, defined as one that occurred after an initial unremarkable postoperative CT scan, contributed to most cases of postoperative hemorrhage in patients with epidermoid cyst. In this study, the authors focus on delayed hemorrhage as one of the severe postoperative complications in epidermoid cyst, report its incidence and its clinical features, and analyze related clinical parameters.
There were 428 cases of intracranial epidermoid cysts that were surgically treated between 2002 and 2008 in Beijing Tiantan Hospital, and these were retrospectively reviewed. Among them, the cases with delayed postoperative hemorrhage were chosen for analysis. Clinical parameters were recorded, including the patient's age and sex, the chief surgeon's experience in neurosurgery, the year in which the operation was performed, tumor size, adhesion to neurovascular structures, and degree of resection. These parameters were compared in patients with and without delayed postoperative hemorrhage to identify risk factors associated with this entity.
The incidences of postoperative hemorrhage and delayed postoperative hemorrhage in patients with epidermoid cyst were 5.61% (24 of 428) and 4.91% (21 of 428), respectively, both of which were significantly higher than that of postoperative hemorrhage in all concurrently treated intracranial tumors, which was 0.91% (122 of 13,479). The onset of delayed postoperative hemorrhage ranged from the 5th to 23rd day after the operation; the median time of onset was the 8th day. The onset manifestation included signs of intracranial hypertension and/or meningeal irritation (71.4%), brain herniation (14.3%), seizures (9.5%), and syncope (4.8%). Neuroimages revealed hematoma in 11 cases and subarachnoid hemorrhage in 10 cases. The rehemorrhage rate was 38.1% (8 of 21). The mortality rate for delayed postoperative hemorrhage was 28.6% (6 of 21). None of the clinical parameters was correlated with delayed postoperative hemorrhage (p > 0.05), despite a relatively lower p value for adhesion to neurovascular structures (p = 0.096).
Delayed postoperative hemorrhage contributed to most of the postoperative hemorrhages in patients with intracranial epidermoid cysts and was a unique postoperative complication with unfavorable outcomes. Adhesion to neurovascular structures was possibly related to delayed postoperative hemorrhage (p = 0.096).
Xiaohui Ren, Song Lin, Zhongcheng Wang, Lin Luo, Zhongli Jiang, Dali Sui, Zhiyong Bi, Yong Cui, Wenqing Jia, Yan Zhang, Lanbing Yu and Siyuan Chen
Most intracranial epidermoid cysts typically present with long T1 and T2 signals on MR images. Other epidermoid cysts with atypical MR images are often misdiagnosed as other diseases. In this study the authors aimed to analyze the incidence and the clinical, radiological, and pathological features of atypical epidermoid cysts.
Among 428 cases of intracranial epidermoid cysts that were surgically treated between 2002 and 2008 at Beijing Tiantan Hospital, cases with an atypical MR imaging appearance were chosen for analysis. Clinical and pathological parameters were recorded and compared in patients with lesions demonstrating typical and atypical MR appearance.
An atypical epidermoid cyst accounts for 5.6% of the whole series. Radiologically, 58.3% of atypical epidermoids were misdiagnosed as other diseases. Compared with a typical epidermoid cyst, atypical epidermoid lesions were significantly larger (p = 0.016, chi-square test). Pathologically, hemorrhage was found in 21 patients with atypical epidermoid cyst and is significantly correlated with granulation (p = 0.010, Fisher exact test). Old hemorrhage was found in 13 cases and was significantly correlated with cholesterol crystals. Twenty-one patients were followed up for 1.3–8.6 years after surgery. The 5- and 8-year survival rates were both 100%. Three patients experienced cyst recurrence. The 5- and 8-year recurrence-free rates were 95% and 81.4%, respectively.
Radiologically, an atypical epidermoid cyst should be differentiated from dermoid cyst, teratoma, schwannoma, glioma, craniopharyngioma, and cavernous angioma. A tendency toward spontaneous hemorrhage is confirmed in atypical epidermoid cysts, and a hypothesis was proposed for spontaneously intracystic hemorrhage in atypical epidermoid cysts. Follow-up confirmed long-term survival of patients with atypical epidermoid cysts.
Xiaohui Ren, Junmei Wang, Mengqing Hu, Haihui Jiang, Jun Yang and Zhongli Jiang
Intracranial and intraspinal malignant peripheral nerve sheath tumors (MPNSTs) are rarely reported because of their extremely low incidence. Knowledge about these tumors is poor. In this study the authors aimed to analyze the incidence and clinical, radiological, and pathological features of intracranial and intraspinal MPNSTs.
Among 4000 cases of intracranial and intraspinal PNSTs surgically treated between 2004 and 2011 at Beijing Tiantan Hospital, cases of MPNST were chosen for analysis and were retrospectively reviewed. To determine which parameters were associated with longer progression-free survival (PFS) and overall survival (OS), statistical analysis was performed.
Malignant PNSTs accounted for 0.65% of the entire series of intracranial and intraspinal PNSTs. Twenty-four (92.3%) of these 26 MPNSTs were primary. Radiologically, 26.9% (7 of 26) of the MPNSTs were misdiagnosed as nonschwannoma diseases. Twenty-one patients were followed up for 1.5 to 102 months after surgery. Twelve patients experienced tumor recurrence, and median PFS was 15.0 months. The 2- and 3-year PFS rates were 47.7% and 32.7%, respectively. Five patients died of tumor recurrence, and median OS was not available. The 2- and 3-year OS rates were 74.7% and 64.0%, respectively. Univariate analysis revealed that female sex, total tumor removal, and primary MPNSTs were significantly associated with a better prognosis. Multivariate analysis revealed that only total removal was an independent prognostic factor for both PFS and OS.
Malignant PNST within the skull or spinal canal is a rare neoplasm and is seldom caused by benign schwannomas. Radiologically, intracranial or intraspinal MPNST should be differentiated from meningioma, chordoma, fibrous dysplasia of bone, and ear cancer. Total resection whenever possible is necessary for the prolonged survival of patients, especially males.
Zhiyong Bi, Xiaohui Ren, Junting Zhang and Wang Jia
Intracranial subependymomas are rarely reported due to their extremely low incidence. Knowledge about subependymomas is therefore poor. This study aimed to analyze the incidence and clinical, radiological, and pathological features of intracranial subependymomas.
Approximately 60,000 intracranial tumors were surgically treated at Beijing Tiantan Hospital between 2003 and 2013. The authors identified all cases in which patients underwent resection of an intracranial tumor that was found to be pathological examination demonstrated to be subependymoma and analyzed the data from these cases.
Forty-three cases of pathologically confirmed, surgically treated intracranial subependymoma were identified. Thus in this patient population, subependymomas accounted for approximately 0.07% of intracranial tumors (43 of an estimated 60,000). Radiologically, 79.1% (34/43) of intracranial subependymomas were misdiagnosed as other diseases. Pathologically, 34 were confirmed as pure subependymomas, 8 were mixed with ependymoma, and 1 was mixed with astrocytoma. Thirty-five patients were followed up for 3.0 to 120 months after surgery. Three of these patients experienced tumor recurrence, and one died of tumor recurrence. Univariate analysis revealed that shorter progression-free survival (PFS) was significantly associated with poorly defined borders. The association between shorter PFS and age < 14 years was almost significant (p = 0.51), and this variable was also included in the multivariate analysis. However, multivariate analysis showed showed only poorly defined borders to be an independent prognostic factor for shorter PFS (RR 18.655, 95% CI 1.141–304.884, p = 0.040). In patients 14 years of age or older, the lesions tended to be pure subependymomas located in the unilateral supratentorial area, total removal tended to be easier, and PFS tended to be longer. In comparison, in younger patients subependymomas tended to be mixed tumors involving the bilateral infratentorial area, with a lower total removal rate and shorter PFS.
Intracranial subependymoma is a rare benign intracranial tumor with definite radiological features. Long-term survival can be expected, although poorly defined borders are an independent predictor of shorter PFS. All the features that differ between tumors in younger and older patients suggest that they might have different origins, biological behaviors, and prognoses.
Haihui Jiang, Zhe Zhang, Xiaohui Ren, Wei Zeng, Junmei Wang and Song Lin
1p/19q co-deletion is a well-established tumor cell–specific chromosomal abnormality in oligodendroglial tumors. The endothelial cells (ECs) of oligodendroglial tumor vessels are considered to be normal cells that do not acquire mutations.
A total of 30 samples from 16 male and 14 female patients (median age of 46.5 years) with a histological diagnosis of primary anaplastic oligodendroglioma (AO) were collected in the study. The immunofluorescence technique was used to identify vascular ECs, and the 1p/19q status was detected with fluorescence in situ hybridization. Kaplan-Meier plots were compared using the log-rank method.
The ECs in AO had a higher 1p36 (detected signal) deletion rate than 1q25 (reference signal) (p < 0.01) and a higher 19q13 (detected signal) deletion rate than 19p13 (reference signal) (p < 0.01). The survival analysis results showed that both the progression-free survival (PFS) and overall survival (OS) of the patients with 1p/19q–co-deleted ECs were significantly longer than those with 1p/19q-intact ECs (PFS, p < 0.001; OS, p < 0.001). This correlation was validated by an independent cohort. In addition, the Cox regression model revealed that 1p/19q co-deletion in ECs was an independent prognostic factor (HR 0.056 [95% CI 0.012–0.261], p < 0.001 for PFS; HR 0.061 [95% CI 0.013–0.280], p < 0.01 for OS).
1p/19q co-deletion and polysomy can be also found in the ECs of AO, which suggests that the ECs are, in part, tumor related and reflect a novel aspect of tumor angiogenesis.
Haihui Jiang, Yong Cui, Xiang Liu, Xiaohui Ren, Mingxiao Li and Song Lin
The aim of this study was to investigate the relationship between extent of resection (EOR) and survival in terms of clinical, molecular, and radiological factors in high-grade astrocytoma (HGA).
Clinical and radiological data from 585 cases of molecularly defined HGA were reviewed. In each case, the EOR was evaluated twice: once according to contrast-enhanced T1-weighted images (CE-T1WI) and once according to fluid attenuated inversion recovery (FLAIR) images. The ratio of the volume of the region of abnormality in CE-T1WI to that in FLAIR images (VFLAIR/VCE-T1WI) was calculated and a receiver operating characteristic curve was used to determine the optimal cutoff value for that ratio. Univariate and multivariate analyses were performed to identify the prognostic value of each factor.
Both the EOR evaluated from CE-T1WI and the EOR evaluated from FLAIR could divide the whole cohort into 4 subgroups with different survival outcomes (p < 0.001). Cases were stratified into 2 subtypes based on VFLAIR/VCE-T1WI with a cutoff of 10: a proliferation-dominant subtype and a diffusion-dominant subtype. Kaplan-Meier analysis showed a significant survival advantage for the proliferation-dominant subtype (p < 0.0001). The prognostic implication has been further confirmed in the Cox proportional hazards model (HR 1.105, 95% CI 1.078–1.134, p < 0.0001). The survival of patients with proliferation-dominant HGA was significantly prolonged in association with extensive resection of the FLAIR abnormality region beyond contrast-enhancing tumor (p = 0.03), while no survival benefit was observed in association with the extensive resection in the diffusion-dominant subtype (p = 0.86).
VFLAIR/VCE-T1WI is an important classifier that could divide the HGA into 2 subtypes with distinct invasive features. Patients with proliferation-dominant HGA can benefit from extensive resection of the FLAIR abnormality region, which provides the theoretical basis for a personalized resection strategy.