Object: 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. Methods: 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. Results: 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. Conclusions: 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.
Background: This study was designed to explore the progression patterns of IDH-wildtype glioblastoma (GBM) at first recurrence after chemoradiotherapy. Methods: Records from 247 patients who underwent progression after diagnosis of IDH-wildtype GBM was retrospectively reviewed. Progression patterns were classified as either local, distant, subependymal or leptomeningeal dissemination based on the preoperative and serial postoperative radiographic images. The clinical and molecular characteristics of different progression patterns were analyzed. Results: A total of 186 (75.3%) patients had local progression, 15 (6.1%) patients had distant progression, 33 (13.3%) patients had subependymal dissemination, and 13 (5.3%) patients had leptomeningeal dissemination. The most favorable survival occurred in patients with local progression, while no significant difference of survival was found among patients with distant progression, subependymal or leptomeningeal dissemination who were thereby reclassified into non-local group. Multivariable analysis showed that chemotherapy was a protective factor for non-local progression, while gender of male, subventricular zone (SVZ) involvement and O6-methylguanine-DNA-methyltransferase (MGMT) promoter methylation were confirmed as risk factors for non-local progression (P < 0.05). Based on the factors screened by multivariable analysis, a nomogram was constructed which conferred high accuracy in predicting non-local progression. Patients in non-local group could be divided into long- and short-term survivors who differed in the rates of SVZ involvement, MGMT promoter methylation and reirradiation (P < 0.05), and a nomogram integrating these factors showed high accuracy in predicting long-term survivors. Conclusion: Patients harboring different progression patterns conferred distinct clinical and molecular characteristics. Our nomograms could provide theoretical references for physicians to make more personalized and precise treatment decisions.