TABLE 2:
Combination of two MR imaging signs of tumor recurrence versus radiation necrosis results
| CC MID | CC SUB | CC MEF | CC SPW | CC SEP | MID SUB | MID MEF | MID SPW | MID SEP | SUB MEF | SUB SPW | SUB SEP | MEF SPW | MEF SEP | SPW SEP | Pathologic Diagnosis | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Presence | 5 | 10 | 7 | 10 | 8 | 7 | 4 | 7 | 5 | 9 | 12 | 10 | 9 | 7 | 10 | Necrosis |
| Absence | 19 | 14 | 17 | 14 | 16 | 17 | 20 | 17 | 19 | 15 | 12 | 14 | 15 | 17 | 14 | Necrosis |
| Presence | 12 | 21 | 19 | 13 | 12 | 13 | 11 | 5 | 4 | 20 | 14 | 13 | 12 | 11 | 5 | Tumor |
| Absence | 18 | 9 | 11 | 17 | 18 | 17 | 19 | 25 | 26 | 10 | 16 | 17 | 18 | 19 | 25 | Tumor |
| P value* | .15 | .05 | .02 | 1 | .78 | .4 | .13 | .33 | .48 | .05 | 1 | 1 | 1 | .77 | .07 | |
| Sign favors diagnosis of: | Tumor | Tumor | Tumor | Neither | Tumor | Tumor | Tumor | Neither | Neither | Tumor | Neither | Neither | Tumor | Tumor | Necrosis | |
| Se (%) | 40.0 | 70 | 63.3 | N/A | 40 | 43 | 36.7 | N/A | N/A | 66.7 | N/A | N/A | 40 | 36.7 | 41.7 | |
| Sp (%) | 79.2 | 58.3 | 70.8 | N/A | 66.7 | 70.8 | 83.3 | N/A | N/A | 62.5 | N/A | N/A | 62.5 | 70.8 | 83.3 | |
| PPV (%) | 70.6 | 67.7 | 73.1 | N/A | 60 | 65 | 73.3 | N/A | N/A | 69 | N/A | N/A | 57.1 | 61.1 | 66.7 | |
| NPV (%) | 51.4 | 60.9 | 60.7 | N/A | 47.1 | 50 | 51.3 | N/A | N/A | 60 | N/A | N/A | 45.5 | 47.2 | 64.1 | |
| Accuracy | 57.4 | 64.8 | 66.7 | N/A | 51.9 | 55.6 | 57.4 | N/A | N/A | 64.8 | N/A | N/A | 50 | 51.9 | 64.8 |
CC indicates corpus callosum involvement; MID, midline spread; SUB, subependymal spread; MEF, new discrete multiple enhancing foci; SPW, “spreading wavefront” appearance; SEP, septum pellucidum involvement; Se, sensitivity; Sp, specificity; PPV, positive predictive values; and NPV, negative predictive values.
*
Fisher’s exact 2-tailed test.