Table I.
Main characteristics of all of the studies included in the meta-analysis.
| First author | Year | Study region | Ethnicity | Number of participants (M/F) | Median follow-up, months(range) | Disease type | Stage | Treatment | Median age, years (range) | NLR cut-off | Outcome | HR | Covariates | (Refs.) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Alagappan | 2018 | USA | Caucasian | 208 (109/99) | 7.5 (4.6-12.0) | Pancreatic adenocarcinoma | Advanced | Combined | 75.2 (65.9-86.1) | 5 | OS/LR | R (M/U) | Albumin; RBC; prior chemotherapy (yes) | (34) |
| Cannon | 2015 | USA | Caucasian | 59 (31/28) | 17 | NSCLC | Early | SBRT | 70 (48-89) | 2.98 | OS | R (U) | - | (33) |
| Chowdhary | 2018 | USA | Caucasian | 188 (91/97) | 13.2 | Brain metastases | Advanced | Combined | NR | 6 | OS | R (M/U) | Active systemic disease; extracranial metastases; graded prognostic assessment; targeted therapy post-SRS; immunotherapy post-SRS | (32) |
| Giuliani | 2016 | Canada | Caucasian | 122 (60/62) | 26.9 (1.3-99.3) | NSCLC | Early | SBRT | 76 (48-90) | 3 | OS | R (M/U) | Female sex; tumor stage T2; hemoglobin | (31) |
| Lai | 2020 | China | Asian | 72 (61/11) | 67.2 (7.7-127.4) | HCC | Early | SBRT | 57 (30-84) | 1.88 | OS | R (M) | - | (30) |
| Mills | 2019 | USA | Caucasian | 27 (12-15) | 8 (1-66) | Malignant adrenal lesions | Advanced | Combined | 63 (51-78) | 4.1 | OS | R (M/U) | Pretreatment ALC >1x106/ml | (29) |
| Sebastian | 2019 | USA | Caucasian | 156 (89-67) | 13.4 | NSCLC | All stages | SBRT | 72 (51-92) | 3.6 | OS | R (M/U) | Age; sex; T stage; histology; ECOG performance status; Charlson's Comorbidity Index; smoking; BED Gy10 | (28) |
| Shaverdian | 2016 | USA | Caucasian | 118 | 28.9 | NSCLC | Early | SBRT | 76 | 2.18 | DMFS/DSS/OS | R (U) | - | (27) |
| Zhuang | 2019 | China | Asian | 60 (49/11) | 36.9 (4.1-73.5) | HCC | ALL stages | Combined | 61.0±12.8 | 2.7 | PFS/OS | R (M/U) | Presence of hepatitis; tumor size (≥1.5cm); pre-treatment pre-treatment AFP (≥20.0 ng/ml); pre-treatment RBC (≥4.5x1012/l); post-treatment PLR (≥263.0) | (26) |
M, male; F, female; USA, United States of America; NSCLC, non-small cell lung cancer; HCC, hepatocellular carcinoma; SBRT, stereotactic body radiation therapy; NR, not reported; OS, overall survival; LR, local recurrence; PFS, progression-free survival; DMFS, distant metastasis-free survival; DSS, disease-specific survival; NLR, neutrophil-to-lymphocyte ratio; HR, hazard ratio; R, obtained by reporting in text; M, multivariate analysis; U, univariate analysis; RBC, red blood cell; SRS, stereotactic radiosurgery; ALC, absolute lymphocyte count; ECOG, Eastern Cooperative Group; BED, biologically effective dose; AFP, α-fetoprotein; PLR, platelet-to-lymphocyte ratio.