In Sook Lee, Presenter: Nothing to Disclose

You Seon Song, Abstract Co-Author: Nothing to Disclose

Hie Bum Suh MD, Abstract Co-Author: Nothing to Disclose

Se Kyoung Park, Abstract Co-Author: Nothing to Disclose

Jeung Il Kim MD, PhD, Abstract Co-Author: Nothing to Disclose

Jong Woon Song, Abstract Co-Author: Nothing to Disclose

To evaluate the presence or absence of recurrent or remnant lesion during post-operative follow-up of malignant or locally aggressive tumors by using dynamic constrast enhanced (DCE, perfusion image) and diffusion weighted images (DWI).

From January 2013 to February 2014, 24 patients (16 women, 8 men; age range, 18-84 years; mean age, 50 years) with 33 follow-up MR images performed DCE and DW images adding to conventional MR images after surgical removal of malignant or locally aggressie tumors. The day interval between first operation and follow-up date was ranged 7-439 days (mean 151 days). On conventional MR images, we evaluated the presence or absence of definite mass or nodule formation and focally fluid or hematoma formation at operation site, and edema and fascial thickening adjacent operation site. We measured apparent diffusion coefficient (ADC) values on ADC maps calculated from DWI. On DCE images, we obtained the values of Ktrans, Kep, Ve, iAUC. And also, time-concentration curve (TCC) was automatically obtained with 7 types.

20 patients had malignant soft tissue tumors, two maligant bone tumors and two Langerhans cell histiocytosis. Seven patients performed follow-up MR images of two-times and one performed three-times. Among 33 follow-up MR images, 12 cases had recurred or remnant lesions confirmed with re-operation. Only 4 cases were confirmed with no recurred or residual lesions through the re-operation and remaining 17 cases were determined with clinical and imaging follow-up more than 6 months. The factors evaluated on coventional MR images were all statistically insignificant (p < 0.05). On DCE images, the values of Ktrans and iAUC and TCC patterns were significant (p < 0.05). On DWI, the values of ADC were significant (p<0.05).

For evaluating the presence or absence of recurrence or remnant lesion at operation site after surgical removal of malignant or locally aggressive tumors, DCE and DWI were more effective than conventional MR images.

In the cases that the determination of recurred or remnant lesion at previous operation site is difficult on follow-up MR images, these functional MR images might be helpful for avoiding unnecessary re-operation or procedures.

Lee, I, Song, Y, Suh, H, Park, S, Kim, J, Song, J, Post-operative Follow-up MRI of Malignant or Locally Aggressive Tumors: Tissue 4D Perfusion and Diffusion Weighted Images.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14045558.html