Clinical stage I non-small cell lung cancer including FDG-PET Imaging: sites and time to recurrence

Positron emission tomography (PET) has improved the accuracy of staging non-small cell lung cancer (NSCLC), although some early-stage patients will still relapse. The purpose of this study was to determine the sites and time to recurrence in patients with clinical stage I NSCLC whose initial staging evaluation included conventional imaging and fluorodeoxyglucose-PET.

This study was approved by our institutional review board and complies with the Health Insurance Portability and Accountability Act. We retrospectively searched our PET database and identified 231 patients (125 women, 106 men; ages 36-93 years) with primary NSCLC and clinical stage I disease. The sites and time to recurrence were recorded. The average follow-up time was 33 months.

Of the 231 patients with clinical stage I tumors, 196 patients (85%) had pathological stage I disease. Two patients developed a second primary lung cancer, and 40 patients (20%) developed local or distant recurrence. Ninety-three percent of all patients remained disease free at 1 year, and 27% (11/40) of those who recur do so in the first year. The most common site of first recurrence was the thorax, followed by the brain, bone, and adrenal glands.

Twenty percent of stage I NSCLC patients staged with conventional imaging and PET will develop recurrent NSCLC. The sites of recurrence with the addition of PET are similar to those reported with staging by conventional imaging alone. Additional studies are needed to determine the optimal time for follow-up imaging if intervention for recurrent disease is shown to improve survival.