The aim of this poster is to review the most common CT patterns occurring during follow-up after RFA in patients with NSCLC,
through the experience of our center.
Particular attention was devoted to highlighting CT findings which are not expected after successful RFA and therefore labelled as “red flags” for progression of incompletely ablated tumor or recurrence.
In patients with initial stage NSCLC,
stage IA (T1ab N0),
surgery represents the first line treatment because its survival rate (about 50% at 5 years) is higher than any other treatment.
in some cases surgery is not possible because of medical comorbidities or because of patients’ refusal.
In such patients,
alternative treatments are radiation therapy (including stereotactic body radiation therapy – SRBT) and thermal ablation – whether in the form of radiofrequency ablation (RFA),
microwave ablation or cryoablation.
RFA use in lung cancer...
Findings and procedure details
Contrast enhanced CT and PET-CT play a key role in radiological follow-up after RFA.
There is no standard imaging protocol after RFA which has been widely adopted.
within the first month after the procedure,
contrast-enhanced CT is usually preferred because PET uptake in this timeframe is not specific.
Later evaluations generally involve alternating CT and PET-CT every 3 months for up to 2 years.
Contrast enhanced CT allows early detection of recurrences or residual tumor tissue proliferation.
Generally a contrast enhancement greater than 15...
CT follow up plays an essential role in patients who undergo RFA and it is therefore important for radiologists to gain a solid knowledge of the most common imaging findings expected after successful RFA.
understanding of unexpected findings (“red flags”) is of the utmost importance for the early identification of incompletely ablated tumor and loco-regional or systemic progression of disease.
Whenever CT findings remain ambiguous,
further CT follow-up and/or PET-CT can yield more definite results .
Resident doctor in Radiology
Department of Radiology - Catholic University of Sacred Heart - Policlinico “A.
Gemelli” Foundation – Rome,
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