Evaluation of RANO Response Criteria Compared to Clinician Evaluation in Grade 3 Anaplastic Astrocytoma (AA): Implications for Clinical Trial Reporting
| Authors | |
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| Year of publication | 2014 |
| Type | Conference abstract |
| MU Faculty or unit | |
| Citation | |
| Description | Purpose/Objectives: Appropriate determination of progression is increasingly important for evaluation of the efficacy novel treatment strategies in AA. Although RANO response criteria have been developed for contrast-enhancing high-grade gliomas, the majority of grade III tumors are minimally enhancing. Thus RANO criteria may not apply to grade III tumors. In this study, we compared progression free survival (PFS) by RANO criteria with retrospective clinical impression to evaluate utility of RANO criteria in grade III AA. Materials/Methods: We reviewed follow-up MR images for 21 consecutive patients diagnosed with AA who developed radiologically proven recurrence after irradiation at our institution. 57% had biopsy only, 33% subtotal resection and 10% of patients received gross total resection. All patients received concurrent chemoradiation with temozolomide and EBRT (median dose 59.4Gy, 33 fractions). Three different criteria for identification of progression were used for each patient: 1) standard RANO-based criteria (RANO-C; most often met by development of new contrast enhancement or enlargement of contrast-enhancing lesion), 2) RANO criteria for progression based on significant FLAIR increase (RANO-F) and 3) clinical progression based oncologist interpretation of imaging and clinical status usually resulting in change in treatment (Clinical). Time to progression was assessed among the three criteria using Friedman’s test, and pairwise criteria using a sign test. Results: Median overall survival was 25 months. 13 (62%) patients had contrast-enhancing disease at diagnosis. Development of new contrast enhancement was the most common determinant of progression (14 patients, 67%). The timing of PFS was significantly different among the 3 criteria (p<0.001, Friedman’s test); 9.2 months for both RANO-C and RANO-F and 12.6 months for Clinical. RANO-F versus RANO-C were determined at the same time in 14 patients (p=0.45, sign test). RANO-C preceded Clinical in 71% of patients (Sign test, p<.0001, median 3.13 months, IQR = 1.6-6.3 months). For the remaining 29%, RANO-C and Clinical were concurrent. Similarly, RANO-F preceded Clinical in 57% of patients (Sign test, p=.04, median 5.4 months, IQR = 2.7-10.7 months). In 6 patients (29%) Clinical was concurrent with RANO-F; 4 of 6 also met RANO-C. Conclusion: RANO criteria for determination of progression results in statistically significant PFS difference in AA compared with clinician assessment. Caution should be taken in comparing PFS in future studies utilizing RANO criteria with historical controls. Further study is necessary to determine the clinical significance of these findings. |