KCR 2012








Notification of abstract acceptance announced via E-mail on July 31st.

Abstract view

Oct. 18 (Thu) Grand Ballroom 105 Room - SS11 NR

17:10-17:20 [SS 11 NR-08]
Differentiation of True Progression from Pseudoprogression in Glioblastoma Treated with Radiotherapy Plus Concomitant Temozolomide Using Apparent Diffusion Coefficient Value by Histogram Analysis.


● Speaker	Hee Ho Chu (Seoul National University Hospital)
● Authors	Hee Ho Chu,Seung Hong Choi,Ji Hoon Kim,Tae Jin Yun,Chul Ho Sohn
● Affiliation	Seoul National University Hospital
● PDF View	SS 11 NR-08.pdf

PURPOSE:
To explore the role of histogram analysis of apparent diffusion coefficient(ADC) maps obtained at standard (1000sec/mm²) and high (3000sec/mm²) b value diffusion-weighted imaging for differentiation of true progression from pseudoprogression in glioblastoma treated with radiotherapy plus concomitant temozolomide.

MATERIALS AND METHODS:
Twenty two patients with histopathologically proven glioblastoma who had undergone concurrent chemoradiotherapy with temozolomide underwent diffusion weighted magnetic resonance imaging with b values of 1000 and 3000 sec/mm², and the corresponding ADC maps (ADC₁₀₀₀ and ADC₃₀₀₀, respectively) were calculated from entire newly developed or enlarged enhancing lesions after completion of chemorariotherapy with temozolomide. Histogram parameters of each ADC maps between true progression (n=11) and pseudoprogression (n=11) were compared using unpaired student’s t-test. Receiver operating characteristic analysis was applied to determine the best cutoff values for the histogram parameters that proved to be significant predictors in differentiating true progression from pseudoprogression.

RESULTS:
In terms of cumulative histograms, the fifth percentile value (C5) of both ADC₁₀₀₀and ADC₃₀₀₀ showed significantly lower in true progression group than pseudoprogression group (P= .049, and P = <.001, respectively). In contrast, both mean ADC₁₀₀₀ and ADC₃₀₀₀ value were not significantly different between the two groups. The diagnostic value of the parameters derived from ADC₁₀₀₀ and ADC₃₀₀₀ were compared, and a significant difference (0.248, P=.028) was found between the areas under the ROC curve of the fifth percentiles for ADC₁₀₀₀ and ADC₃₀₀₀.

CONCLUSION:
The fifth percentile value of the cumulative ADC histogram obtained at a high b value was the most promising parameter for differentiating true progression from pseudoprogression in terms of newly developed or enlarged enhancing lesions after concurrent chemoradiotherapy with temozolomide for glioblastoma.