How often should follow-up examinations be conducted while taking gefitinib?

Generally, patients taking gefitinib should undergo follow-up examinations approximately once every four weeks, although the specific interval may be adjusted according to individual disease progression. Seek medical advice promptly if any abnormalities occur. Detailed analysis is as follows:

For patients taking gefitinib for the first time, the initial follow-up evaluation is typically scheduled 1 to 2 months after starting treatment. A chest CT or MRI is performed to assess changes in tumor size and determine whether the drug is effective. A reduction in tumor diameter exceeding 30% or complete disappearance of the tumor is considered partial or complete response, respectively. If the lesions remain stable for more than four weeks, the disease is classified as stable.

For patients on long-term gefitinib therapy with stable conditions, the follow-up interval can be extended to every 2–3 months. However, if symptoms such as worsening cough, shortness of breath, bone pain, or neurological signs develop, or if tumor progression is detected during follow-up, the monitoring frequency should be increased to every two weeks to allow timely adjustment of the treatment plan.

Liver function, blood counts, and tumor markers must be closely monitored throughout treatment. Patients should not discontinue or alter their dosage without medical guidance. If severe adverse reactions occur—such as rash, diarrhea, or interstitial lung disease—gefitinib should be stopped immediately and medical attention sought.