Table 3.
Comparisons of patients with or without grade 4 lymphopenia in propensity score matched cohort (N = 272).
| Characteristic | Parameter | Grade 0–3 Lymphopenia (N = 193) | Grade 4 Lymphopenia (N = 79) | P value |
|---|---|---|---|---|
| Age | Mean | 59.5 | 62.5 | 0.02 |
| PTV (cc) | Mean | 548 | 601 | 0.05 |
| Gender, N (%) | Female | 21 (66) | 11 (34) | 0.48 |
| Male | 172 (72) | 68 (28) | ||
| Stage, N (%) | I | 3 (75) | 1 (25) | 0.95 |
| IIA | 63 (72) | 24 (28) | ||
| IIB | 7 (64) | 4 (36) | ||
| III | 114 (71) | 47 (29) | ||
| IVA | 6 (67) | 3 (33) | ||
| KPS, N (%) | 70 | 5 (63) | 3 (38) | 0.69 |
| 80–100 | 188 (71) | 76 (29) | ||
| Tumor location, N (%) | Upper-Middle | 8 (80) | 2 (20) | 0.73 |
| Lower | 185 (71) | 77 (29) | ||
| Induction chemotherapy, N (%) | No | 126 (72) | 48 (28) | 0.48 |
| Yes | 67 (68) | 31 (32) | ||
| Histology, N (%) | Adenocarcinoma | 188 (71) | 77 (29) | 1.00 |
| SCC | 5 (71) | 2 (29) | ||
| RT Modality, N (%) | IMRT | 81 (60) | 55 (40) | <0.0001 |
| PBT | 112 (82) | 24 (18) |
Abbreviations: PTV = planning target volume, KPS = Karnofsky performance status, SCC = Squamous cell carcinoma, RT = radiation therapy, IMRT = intensity-modulated radiation therapy, PBT = proton beam therapy.