Prognostic impact of 18F-FDG uptake on PET in non-small cell lung cancer patients with postoperative recurrence following platinum-based chemotherapy.

BACKGROUND

Whether fluorine-18-fluorodeoxyglucose ((18)F-FDG) uptake within tumor cells differs between primary and recurrent lung cancers is unknown. The aim of this study was to investigate the prognostic significance of (18)F-FDG uptake by comparing that measured preoperatively at the primary site to that measured postoperatively at sites of non-small cell lung cancer (NSCLC) recurrence. Only patients with postoperative recurrences who received platinum-based chemotherapy as the initial treatment after recurrence were included in the study.

METHODS

Fifty-two patients underwent (18)F-FDG positron emission tomography (PET) examinations before thoracotomy and at the time of recurrence after curative surgery. All recurrences were treated with platinum-based chemotherapy.

RESULTS

(18)F-FDG uptake in the preoperative primary tumors was significantly higher than that in the recurrent tumors (p=0.028), demonstrating a statistically significant correlation (Pearson's correlation coefficient γ=0.482, p<0.001), especially in adenocarcinoma (AC) patients. Low (18)F-FDG avidity within the primary tumor significantly correlated with the presence of epidermal growth receptor factor (EGFR) mutations. (18)F-FDG uptake in the primary tumors was an independent prognostic factor for predicting outcome in NSCLC patients receiving platinum-based chemotherapy for the treatment of postoperative recurrence.

CONCLUSIONS

In NSCLC patients treated by chemotherapy for recurrence, preoperative measurements of (18)F-FDG uptake may be a more powerful surrogate marker for predicting outcome when measured preoperatively at the primary tumor site rather than postoperatively at sites of recurrence.