Akihiro Nishie MD, Presenter: Nothing to Disclose

Daisuke Kakihara, Abstract Co-Author: Nothing to Disclose

Yoshiki Asayama MD, Abstract Co-Author: Nothing to Disclose

Yasuhiro Ushijima MD, Abstract Co-Author: Nothing to Disclose

Yukihisa Takayama MD, Abstract Co-Author: Research Grant, FUJIFILM Holdings Corporation

Hiroshi Honda MD, Abstract Co-Author: Nothing to Disclose

Daisuke Okamoto MD, Abstract Co-Author: Nothing to Disclose

Nobuhiro Fujita MD, PhD, Abstract Co-Author: Nothing to Disclose

Koichiro Morita, Abstract Co-Author: Nothing to Disclose

Yuichiro Kubo MD, Abstract Co-Author: Nothing to Disclose

Junichi Inokuchi, Abstract Co-Author: Nothing to Disclose

To elucidate whether apparent diffusion coefficient (ADC) of a tumor is a predictor of recurrence after nephrectomy in localized renal cell carcinoma (RCC)

We retrospectively studied 49 patients with localized RCC who underwent magnetic resonance imaging including diffusion-weighted imaging preoperatively. Fifteen patients developed recurrence during follow-up periods of 89 to 1837 days, while the remaining 34 showed no recurrence during follow-up periods of 1209 to 4822 days. ADC was measured by placing a region-of-interest in each tumor on ADC map, as avoiding necrosis and hemorrhage. Mean ADC was calculated by averaging ADC values obtained from three images, and minimum ADC was defined as the lowest ADC value among the three. The correlations between clinicopathological variables that could affect recurrence (age, gender, tumor side, tumor size, growth/invasion pattern, Fuhrman’s grade, histology, venous invasion, average ADC and minimum ADC) and disease free survival were analyzed using Cox proportional hazards model.

In univariate analysis, tumor size, venous invasion, mean ADC and minimum ADC showed significant correlations with disease free survival (p < 0.05). In multivariate analysis, only venous invasion and minimum ADC revealed significance (p < 0.05).

Minimum ADC of a tumor, as well as venous invasion, was an independent predictor of recurrence after nephrectomy in localized RCC.

Because a localized RCC showing low minimum ADC may recur in the early stage, we can propose the necessity of adjuvant therapy and shortening of the follow-up interval by imaging after surgery for such a tumor.

Nishie, A, Kakihara, D, Asayama, Y, Ushijima, Y, Takayama, Y, Honda, H, Okamoto, D, Fujita, N, Morita, K, Kubo, Y, Inokuchi, J, Apparent Diffusion Co-efficient as a Predictor of Recurrence after Nephrectomy in Localized Renal Cell Carcinoma.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14008888.html