Table 2.
Risk factors associated with RILD after reirradiation
| Variables | RILD (+) | RILD (−) | Univariate | Multivariate | ||
|---|---|---|---|---|---|---|
| p value | p value | OR | 95 % CI | |||
| Total number | 13 | 23 | ||||
| Liver function before 2nd RT | ||||||
| Total bilirubin ≧2.0 mg/dL | 4 | 0 | 0.016 | |||
| Albumin ≦3.5 g/dL | 8 | 4 | 0.007 | |||
| Presence of ascites | 3 | 1 | 0.086 | |||
| INR ≧1.71 | 0 | 0 | ||||
| CTP score ≧6 | 10 | 4 | <0.0001 | 0.001 | 15.833 | 2.947 ~ 85.075 |
| Presence of PVTT | 8 | 5 | 0.017 | |||
| AST/ALT ≧3x of upper normal limit | 5 | 1 | 0.088 | |||
| Hepatitis | ||||||
| Hepatitis B infection | 6 | 10 | 0.877 | |||
| Hepatitis C infection | 2 | 6 | 0.458 | |||
| RT parameters of 2nd RT | ||||||
| Mean CTV (cm3) | 158.8 ± 157.9 | 204.2 ± 348.7 | 0.740 | |||
| Mean PTV (cm3) | 257.9 ± 207.8 | 314.4 ± 480.7 | 0.260 | |||
| Mean normal liver dose (EQD2, Gy8) | 12.0 ± 6.8 | 10.2 ± 4.8 | 0.726 | |||
| Mean normal liver volume (cm3) | 1173.4 ± 622.2 | 992.5 ± 196.1 | 0.332 | |||
| Interval between 2 courses (month) | 8.1 ± 8.1 | 12.6 ± 12.3 | 0.247 | |||
| Mean cumulative normal liver dose (EQD2, Gy8) | 32.0 ± 15.0 | 30.6 ± 9.7 | 0.233 | |||
| Mean cumulative prescribed dose (EQD2, Gy15) | 82.8 ± 15.9 | 90.6 ± 15.4 | 0.065 | |||
| Abutting score for two PTV | 1.3 ± 0.9 | 1.1 ± 0.7 | 0.548 | |||
Abbreviation: RILD radiation-induced liver disease, OR odds ratio, CI confidence interval, CTP Child-Turcotte-Pugh, PVTT portal vein tumor thrombosis, AST aspartate aminotransferase, ALT alanine aminotransferase, CTV clinical tumor volume, NS no significance, EQD2 biologically equivalent doses calculated in 2Gy