Infantile Optic Pathway Glioblastoma.

BACKGROUND: Optic pathway gliomas and glioblastomas remain a rare entity within the infant population. CASE DESCRIPTION: We outline the case of a 6-month-old female who presented with failure to thrive, nystagmus and features of raised intracranial pressure. Subsequent magnetic resonance imaging demonstrated an infiltrating tumor radiating from the optic nerves bilaterally. She underwent emergent ventriculoperitoneal shunting and biopsy. Histology confirmed a World Health Organization grade IV glioblastoma. CONCLUSIONS: The patient remained clinically and radiologically stable at 1 year. Optic pathway glioblastoma in this population is a previously undescribed entity that requires multidisciplinary input to guide ongoing therapy.

Intra- and Interobserver Reproducibility Assessment of PD-L1 Biomarker in Non-Small Cell Lung Cancer.

Purpose: Reliable and reproducible methods for identifying PD-L1 expression on tumor cells are necessary to identify responders to anti-PD-1 therapy. We tested the reproducibility of the assessment of PD-L1 expression in non-small cell lung cancer (NSCLC) tissue samples by pathologists.Experimental Design: NSCLC samples were stained with PD-L1 22C3 pharmDx kit using the Dako Autostainer Link 48 Platform. Two sample sets of 60 samples each were designed to assess inter- and intraobserver reproducibility considering two cut points for positivity: 1% or 50% of PD-L1 stained tumor cells. A randomization process was used to obtain equal distribution of PD-L1 positive and negative samples within each sample set. Ten pathologists were randomly assigned to two subgroups. Subgroup 1 analyzed all samples on two consecutive days. Subgroup 2 performed the same assessments, except they received a 1-hour training session prior to the second assessment.Results: For intraobserver reproducibility, the overall percent agreement (OPA) was 89.7% [95% confidence interval (CI), 85.7-92.6] for the 1% cut point and 91.3% (95% CI, 87.6-94.0) for the 50% cut point. For interobserver reproducibility, OPA was 84.2% (95% CI, 82.8-85.5) for the 1% cut point and 81.9% (95% CI, 80.4-83.3) for the 50% cut point, and Cohen's κ coefficients were 0.68 (95% CI, 0.65-0.71) and 0.58 (95% CI, 0.55-0.62), respectively. The training was found to have no or very little impact on intra- or interobserver reproducibility.Conclusions: Pathologists reported good reproducibility at both 1% and 50% cut points. More adapted training could potentially increase reliability, in particular for samples with PD-L1 proportion, scores around 50%. Clin Cancer Res; 23(16); 4569-77. ©2017 AACR.