Radiofrequency ablathermia of pulmonary nodules : CT follow-up and prognostic study

Radiofrequency ablathermia of pulmonary nodules is a local curative treatment whose efficacy assessment is still a current topic.

To specify the monitoring protocol, the scannographic aspects of treated lesions, deduce criteria of incomplete ablation, and identify the prognostic factors influencing overall and progression-free survivals.

A prognostic descriptive retrospective study conducted in the medical imaging department of Abderrahman Mami Hospital. The nodules were monitored at 24-hour, 2.4,6,9,12,15,18 and 24 months after treatment and then once a year. The study of overall and progression-free survivals was done using Kaplan Meier's method.

Sixteen patients with 21 nodules were included, 20% of them were pulmonary carcinomas and 80% were secondary nodules. 6 nodules presented an incomplete response.The appearance of a convex outline was the first sign of incomplete ablation. 5 out of 6 nodules had a nodular focal enhancement. The cumulative probability of overall survival at 12, 36, and 60 months was 80%, 66% and 39% with a median survival of 31 months. The number of nodules treated was found to be directly related to overall survival. The cumulative probability of progression-free survival was 65% at 12, 36 and 60 months. Pleural contact was the factor influencing progression-free survival.

Radiofrequency ablathermia is an effective technique. Regular CT monitoring allows early detection of tumor recurrence.