From the Guidelines
Repeat imaging should be done every 6 to 12 weeks in patients receiving osimertinib therapy for non-small cell lung cancer (NSCLC), as recommended by the NCCN panel 1. This recommendation is based on the NCCN clinical practice guidelines in oncology, which suggest that response assessment of known sites of disease with CT (with contrast) every 6 to 12 weeks is appropriate for patients receiving subsequent therapy, including osimertinib 1.
Key Considerations
- The NCCN panel recommends osimertinib as subsequent therapy for patients with metastatic EGFR T790M–positive NSCLC that has progressed on erlotinib, gefitinib, or afatinib therapy 1.
- Osimertinib has been shown to be associated with a response rate of approximately 71% and disease control rate of approximately 93% in patients whose disease has progressed on sensitizing EGFR TKI therapy 1.
- The timing of imaging may need adjustment based on individual patient factors such as symptom development, disease aggressiveness, or specific mutation profiles (particularly T790M or EGFR mutations) 1.
Imaging Schedule
- Initial assessment: 6 to 12 weeks after starting osimertinib therapy
- Subsequent imaging: every 3 months for the first year, then every 4-6 months thereafter if the disease remains stable
- Earlier assessment should be considered if a patient develops new or worsening symptoms before the scheduled imaging 1.
From the Research
Repeat Imaging after Osimertinib Treatment
- The optimal timing for repeat imaging after starting osimertinib is not explicitly stated in the provided studies 2, 3, 4, 5, 6.
- However, study 3 mentions that patients received computed tomography scans after 31 days of continuous osimertinib treatment, which showed reductions in liver metastases.
- Study 4 reports that progression-free survival was assessed by blinded independent central review, but does not specify the exact timing of repeat imaging.
- Studies 2, 5, 6 do not provide information on the timing of repeat imaging after osimertinib treatment.
Disease Progression and Treatment Response
- Study 4 shows that osimertinib resulted in a significant progression-free survival benefit compared to placebo, with a median progression-free survival of 39.1 months with osimertinib versus 5.6 months with placebo.
- Study 3 reports that osimertinib treatment led to reductions in liver metastases and improvements in liver function tests.
- Study 2 examines the mechanisms of resistance to osimertinib and reports that MET amplification was found in 3/15 patients (20%) who received osimertinib as first-line therapy.
Pharmacokinetics and Safety
- Study 5 assesses the effects of mild and moderate hepatic impairment on the pharmacokinetics of osimertinib and finds that no dose adjustment is required for osimertinib when treating patients with mild or moderate hepatic impairment.
- Study 6 reviews the post-osimertinib treatment options for EGFR-mutated NSCLC and proposes an algorithm to guide clinicians in managing progression on osimertinib.