MR Diffusion-weighted imaging(DWI) of Malignant Melanoma in Head and Neck after Accelerated Carbon-Ion Radiotherapy

PURPOSE: To report change of diffusion weighted imaging(DWI) of malignant melanoma in head and neck after carbon-ion radiotherapy. MATERIAL and METHOD: Eighteen patients having malignant melanoma in head and neck regions undertook carbon-ion radiotherapy at the National Institute of Radiological Sciences, Chiba, Japan. We examined using DWIBS (diffusion-weighted imaging with background body signal suppression) method before and after the treatment. ADC (apparent diffusion coefficient) value was measurable in nine of 18 cases (mean age:65yrs,age range:56-78,5 males and 4 females). We compared the ADC value before the treatment with the after one. Intera Achieva 1.5T Nova Dual system (Philips Medical) was used for the examination. The EPI-based diffusion-weighted imaging sequence with SPIR fat suppression was applied at the settings of two b-values, namely 0 and 1000 sec/mm^2, respectively. Results: Average ADC value for all clinical cases were 0.897x10^-3 (S.D.: 0.142x10^-3) at pre-treatment and 1.355x10^-3 (S.D.: 0.573x10^-3) at post-treatment. ADC values were increased in eight of 9 cases and decreased in one. There was a significant difference in ADC value between pre- and post-treatment (P<0.028).CONCLUSIONS: DWIBS examination for malignant melanoma in head and neck showed significant increases in ADC value after carbon-ion radiotherapy. The ADC value has the possibility of becoming a criteria when you judge the effect of the carbon-ion radiotherapy in malignant melanoma.ECR2007 19th European Congress of Radiolog

MR imaging of adenoid cystic carcinoma in the head and neck after carbon ion therapy

Adenoid cystic carcinomas are relatively rare tumors in head and neck. The tumors tend to invade skull base resulting in contraindication of surgeric therapy.17th European Congress of Radiolog