Hideo Gobara MD, Presenter: Nothing to Disclose

Yoshihiro Okumura MD, Abstract Co-Author: Nothing to Disclose

Alafat Alerkin MD, Abstract Co-Author: Nothing to Disclose

Takao Hiraki MD, Abstract Co-Author: Nothing to Disclose

Hidefumi Mimura MD, Abstract Co-Author: Nothing to Disclose

Susumu Kanazawa MD, Abstract Co-Author: Nothing to Disclose

Mitsumasa Kaji MD, Abstract Co-Author: Nothing to Disclose

00030490-DMT et al, Abstract Co-Author: Nothing to Disclose

To prospectively semiquantitative evaluation in FDG PET/CT(PET/CT) imaging features at 3 and 6 months after radiofrequency ablation( RFA ) of lung tumors by LeVeen needle.

A total of 16 patients[ male: 11, female: 6] with 24 lung tumors( metastatic tumor: 17, primary lung carcinoma: 7)( primary site of metastases; colorectal carcinoma: 11, primary lung carcinoma: 4, hepatocellular carcinoma: 2, mean size, 14.8 ± 8.1 mm)( mean age, 65.9± 11.4 years) were studied. Mean of periods of before RFA( Pre RFA) was 21.4 ± 23.2 days, of 3 months after RFA( 3M) was 96.8 ± 10.1 days, and of 6 months after RFA( 6M)was 189.2 ± 10.2 days. PET-CT were acquired after at least 5-h fasting, the patients was received intravenously injection of 0.1 mCi( 37 MBq)/ kg of FDG. The FDG-PET images were obtained 90 minute after the FDG injection. The technical parameter for a 16- detector row helical CT included a section thickness 3 mm. Areas of focally increased glucose uptake were evaluated by the maximum standardized uptake values (SUVmax) for each site which is calculated by the conventional formula normalized for body weight. RFA were performed by LeVeen needle, 14 or 17G, 2- 8 times and rolls per a tumor, with max power 30- 190 w, 9- 41.5 minuates by 4 radiologists who have experience of lung RFA more than 5 years. An each tumor had no local progression which are indicated by contrast enhanced CT at 1 year after RFA. Willcoxon test was calculated among 3 Groups( Pre RFA, 3 M and 6 M). A p value of less than 0.05 was considered indicative of a statistically significant difference.

A SUVmax of 6M was 0.83- 3.6, and a median was. 1.55. It was significant lower than that of Pre RFA, which was 0.56- 7.2, and a median was 2.75 and that of 3 M, which was 0.87- 7.58, and a median was 3.0. There was no significant difference between the SUVmax of Pre RFA and 3M.

On PET- CT imaging feature at 3 months after RFA of lung tumors by Leveen needle, there were higher accumulations in ablated tumors without local progression. And at 6 months after RFA, accumulations were lower than before RFA and 3 months after RFA.

If we perform PET- CT only one time point follow-up, before 1 year after RFA, it is more appropriate , at 6 months than at 3 months after RFA.

Gobara, H, Okumura, Y, Alerkin, A, Hiraki, T, Mimura, H, Kanazawa, S, Kaji, M, et al, 0, Prospective Semiquantitative Analysis on FDG PET-CT Imaging Features before, 3, and 6 Months after RFA of Lung Tumors.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8008695.html