Ultraschall Med 2005; 26 - OP057
DOI: 10.1055/s-2005-917338

THE USEFULNESS OF CONTRAST ENHANCED ULTRASONOGRAPHY IN PATIENTS WITH PANCREATIC CARCINOMA BEFORE AND AFTER CHEMORADIATION THERAPY

M Nishida 1, K Koito 2, N Hirokawa 2, T Satoh 2, M Hori 2, Y Kawai 2, T Shonai 2, M Someya 2, N Yama 2, H Hyodoh 2, M Hareyama 2
  • 1Radiation Oncology, Imaging and Diagnosis, Sapporo Medical University Graduate school of Medicne
  • 2Department of Radiology, Sapporo Medical University, Sapporo, Japan

Purpose: The aim of our study was to investigate the hemodynamic response to treatment, as shown by contrast enhanced ultrasonography (EU).

Methods and Materials: Seventeen patients with unresectable Stage IVa/ IVb pancreatic carcinoma were enrolled. Pathologically, all tumors were proven to be adenocarcinoma. EU was performed before and after chemoradiation. We assigned the intratumoral enhancement pattern of EU, a score of 1 for weakly positive, 2 for positive, 3 for strongly positive and 4 for very strongly positive

The treatment effect was estimated by CT. IMD (intratumoral microvessel density) was calculated by means of CD 34 immune staining. Also average of microvessel diameter (AVD) was calculated in the same areas. VEGF staining was graded on a scale of 0(<25%), 1(<50%), 2(<75%) and 3(>=75%). Intratumoral enhancement patterns were evaluated and compared to those IMD, AVD and VEGF.

Results: One out of seventeen cases responded completely (CR) to therapy, nine responded partially (PR), and eight were unchanged (NC). The median EU score of PR/CR cases was 3, while NC showed 2. At the same time, average IMD of CR/PR was 17.1, NC was 9.9, median VEGF grade of CR/PR was 2, NC was 1. CR/PR showed higher score of EU, IMD and VEGF than NC. There is a significant difference between IMD and treatment effects (p<0.05).

Both of PR and NC developed increasing enhancement patterns within 7 days post-radiotherapy. EU score was 3 both in CR/PR and NC, IMD of CR/PR and NC were decreased to 3.7, 3.2 respectively, while the AVD were increased both in PR and NC cases, from 2.9 to 13.4 in PR, from 8.2 to 8.8 in NC.

The EU score of PR/CR cases, post chemo radiotherapy was 1, showing diminishment intratumoral enhancement patterns 12 days after the therapy; while IMD was also significantly decreased to 2.3 and VEGF was 0. However, the EU score of NC cases was 2, showed a persisted intratumoral enhancement patterns. VEGF was 1, it was the same grade compared with pre therapy. The alteration of EU score in PR/CR cases decreased from 3 to 1, while NC showed no change, the score has been 2. There is a significant difference between EU score and treatment effects (p<0.05).

Conclusions: NC implied hypovascularity, PR and CR showed tumor hypervascularity pre-treatment, hypervascularity might indicate a high sensitivity to treatment. Increased intratumoral enhancement patterns within 11days post-radiotherapy probably represents dilatation of AVD, this was cased secondary to tumor necrosis and granulomatous change.

To summarize the result, in PR, decreased enhancement pattern results from fibrotic change, whereas in NC, continuous vascular enhancement pattern suggests continued tumor viability after the therapy.

Prior treatment, EU revealed hyper vascularity in the tumors of PR cases, while hypo vascularity in the NC cases. EU can demonstrate intratumoral vascularity to estimate tumor viability and angiogenic activity