Osimertinib after definitive chemoradiotherapy in unresectable stage III epidermal growth factor receptor-mutated non-small-cell lung cancer: analyses of central nervous system efficacy and distant progression from the phase III LAURA study.

BACKGROUND: Distant metastases in non-small-cell lung cancer (NSCLC) are a poor prognostic factor that negatively impact quality of life. The central nervous system (CNS) is a common site of distant progression in epidermal growth factor receptor-mutated (EGFRm) NSCLC. Osimertinib is a third-generation EGFR-tyrosine kinase inhibitor recommended for advanced EGFRm NSCLC and as adjuvant treatment for resected EGFRm NSCLC. In LAURA (NCT03521154), osimertinib demonstrated statistically significant improvement in progression-free survival (PFS) versus placebo in unresectable stage III EGFRm NSCLC without progression during/following chemoradiotherapy (CRT). CNS efficacy and time to death or distant metastases (TTDM) analyses are reported here. PATIENTS AND METHODS: Patients without progression during/following definitive platinum-based CRT were randomised 2 : 1 to receive osimertinib (80 mg daily) or placebo until progression [by blinded independent central review (BICR)] or discontinuation. The primary endpoint was PFS by BICR. CNS PFS by neuroradiologist BICR and TTDM by BICR were secondary endpoints. RESULTS: Overall, 216 patients were randomised (143 osimertinib, 73 placebo). Median CNS PFS by neuroradiologist BICR was not reached [95% confidence interval (CI) not calculable (NC)-NC] with osimertinib versus 14.9 months (95% CI 7.4 months-NC) with placebo; hazard ratio (HR) for CNS PFS: 0.17 (95% CI 0.09-0.32). CNS PFS analysis by investigator assessment was consistent with BICR assessment. The cumulative incidence of CNS progression at 12 months was 9% (95% CI 5% to 14%) with osimertinib and 36% (95% CI 24% to 47%) with placebo. There was clinically meaningful improvement in TTDM with osimertinib versus placebo; HR for TTDM: 0.21 (95% CI 0.11-0.38). The cumulative incidence of distant metastases at 12 months was 11% (95% CI 6% to 17%) with osimertinib and 37% (95% CI 26% to 48%) with placebo. CONCLUSIONS: Osimertinib demonstrated clinically meaningful improvements in CNS PFS and TTDM versus placebo, supporting osimertinib post-CRT as the standard of care in unresectable stage III EGFRm NSCLC.

Recurrence of carcinoma showing thymus-like differentiation (CASTLE) involving the thyroid gland.

BACKGROUND: Carcinoma showing thymus-like differentiation (CASTLE) in the thyroid gland is a rare disease with generally a favorable prognosis. Treatment with surgery and adjuvant radiotherapy has been shown to improve local control and long-term survival rates. In this report, we present a case of a recurrent thyroid gland CASTLE and review the literature on the diagnosis and treatment of this disease. CASE PRESENTATION: A 60-year-old woman, who was diagnosed with a CASTLE thyroid tumor in 2015, had a total thyroidectomy and was maintained on thyroid hormone replacement (levothyroxine). After 5 years, the patient had a recurrence, in an advanced stage unsuitable for surgery. As the patient declined to undergo radiotherapy, she was followed up without intervention and is currently stable after 15 months. CONCLUSIONS: CASTLE is a rare disease, diagnosed based on postoperative pathology and immunohistochemistry analysis, especially upon CD5 marker. In case of relapse, treatment options include surgery and radiotherapy; however conservative management without intervention is an acceptable alternative in some cases.