Intracranial Outcomes of De Novo Brain Metastases Treated With Osimertinib Alone in Patients With Newly Diagnosed EGFR-Mutant NSCLC

Introduction

Patients with EGFR-mutant NSCLC have a high incidence of brain metastases. The EGFR-directed tyrosine kinase inhibitor osimertinib has intracranial activity, making the role of local central nervous system (CNS)-directed therapies, such as radiation and surgery, less clear.

Methods

Patients with EGFR-mutant NSCLC and brain metastases who received osimertinib as initial therapy after brain metastasis diagnosis were included. Individual lesion responses were assessed using adapted RANO-BM criteria. CNS progression and local progression of brain metastasis from osimertinib start were analyzed using cumulative incidence treating death as a competing risk. Overall survival was estimated using Kaplan-Meier methodology.

Results

There were 36 patients who had a median interval from brain metastasis diagnosis to first-line osimertinib initiation of 25 days. In total, 136 previously untreated brain metastases were tracked from baseline. Overall, 105 lesions (77.2%) had complete response and 31 had partial response reflecting best objective response of 100%. Best response occurred at a median of 96 days (range: 28-1113 d) from baseline magnetic resonance imaging. This reflects a best objective response rate of 100%. Two-year overall survival was 80%. CNS progression rates at 1-, 2-, and 3-years post-osimertinib were 21%, 32%, and 41%, respectively. Lesion-level local failure was estimated to be 0.7% and 4.7% at 1- and 2-years post-osimertinib, respectively. No clinicodemographic factors including brain metastasis number were associated with post-osimertinib progression.

Conclusions

Intracranial response to osimertinib is excellent for patients with EGFR-mutant NSCLC with de novo, previously untreated brain metastases. Very low local failure rates support a strategy of upfront osimertinib alone in selected patients.

Cranial intraosseous meningioma: spectrum of neuroimaging findings with respect to histopathological grades in 65 patients

The aim of this study was to determine various imaging features of intraosseous meningiomas (IOMs) and differentiate low-grade from high-grade tumors. The histopathologic evaluation revealed World Health Organization (WHO) grade I tumor in 56 (86%) patients, grade II in 8 (12%), and grade III in 1 (2%) patient. WHO grade I was considered low grade and II and III were designated as high grade. Hyperostosis was observed most commonly in low-grade IOMs. Mixed hyperostotic/lytic pattern with radial bony spiculations and presence of a scalp mass seem to be more frequently associated with higher-grade IOMs.

Diffusion tensor imaging in a child with hypertrophic olivary degeneration

Hypertrophic olivary degeneration (HOD) is caused by disruptive lesions affecting components of the Guillain-Mollaret triangle (GMT). We present conventional magnetic resonance and diffusion tensor imaging (DTI) findings in a 6-year-old girl with HOD after surgery for a midbrain pilocytic astrocytoma. To our knowledge, this is the first dedicated DTI analysis of GMT in a child with HOD in the literature. In our patient, we found higher fractional anisotropy (FA) and axial diffusivity values of the inferior olivary nucleus (ION) and lower FA, but higher radial diffusivity (RD) values of all other GMT components compared to age-matched controls. Increased FA values of the ION may be explained by increased packing of white matter fibers. However, associated hyperintense T2 signal is contradictory and the association between increased FA values and hyperintense T2 signal remains unclear. Low FA and high RD values of the other GMT components likely reflect demyelination with axonal degeneration and correlate well with histopathological findings.

The many faces of fungal disease of the paranasal sinuses: CT and MRI findings

The prevalence of fungal rhinosinusitis has increased worldwide over the last two decades. Fungal rhinosinusitis includes a wide variety of infections, from relatively innocent to rapidly fatal processes. Fungal infection may be one of the most challenging forms of sinonasal pathology to manage, especially the invasive forms, which have high mortality rates. Therefore, it is essential to correctly diagnose and classify fungal disease of paranasal sinuses in order to accurately predict prognosis and implement effective therapy. This essay describes the different manifestations of fungal sinusitis on computed tomography and magnetic resonance imaging to optimize differentiation, and includes correlation with the pathologic classifications.

Abscess formation as a complication of a ruptured urachal cyst

The urachus is a midline tubular structure that extends upward from the dome of the bladder toward the umbilicus. This tubular structure normally involutes before birth, remaining as a fibrous band with no known function. Persistence of all or any portion of the fetal urachus results in several anomalies, the most common of which is the urachal cyst (Yu JS, Kim KW, Lee HJ, Lee YJ, Yoon CS, Kim MJ, Radiographics, 21:451-4611, 2001; Ohgaki M, Higuchi A, Chou H, Takashina K, Kawakami S, Fujita Y, Hagiwara A, Yamagishi H, Surg Today, 33:75-77, 2003). Although most urachal cysts are asymptomatic, there are a few reports about intraperitoneal rupture of infected urachal cysts, all of which caused peritonitis and sepsis (Ohgaki M, Higuchi A, Chou H, Takashina K, Kawakami S, Fujita Y, Hagiwara A, Yamagishi H, Surg Today, 33:75-77, 2003; Kojima Y, Miyake O, Taniwaki H, Morimoto A, Takahashi S, Fujiwara I, Int J Urol, 10:174-176, 2003; Agatstein EH, Stabile BE, Arch Surg, 119:1269-1273, 1984). We report the imaging and operative findings of a patient, presented with a urachal abscess after a spontaneously ruptured urachal cyst.

Symptomatic epidural gas after open diskectomy: CT and MR imaging findings

We report a case of symptomatic epidural gas accumulation after open diskectomy, causing lumbar radiculopathy. Surgery had been performed in a 44-year-old man for disk extrusion; however, he was readmitted to the hospital with increased lower back pain 5 months after the operation. CT and MR studies demonstrated accumulation of gas in the lumbar epidural space compressing the dural sac and nerve root. Symptoms disappeared after surgical removal of the gas.