Table 1.
Characteristics of included studies.
| Year | Author | Region | Treatment | Tumor | Number of Patients |
Time Point After Immunotherapy | Outcome | Gender (Male/Female) |
Newcastle–Ottawa Scale | Study Design | Reference Number |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2017 | Michael R Cassidy | USA | Ipilimumab | Melanoma | 197 | 3 weeks and 6 weeks | OS; PFS | 125/72 | 9 | Retrospective | [35] |
| 2018 | Aly-Khan A Lalani | USA | Anti-PD-1 and anti-PD-L1 | mRCC | 192 | 6 weeks | OS; PFS; ORR | 101/41 | 9 | Retrospective | [21] |
| 2018 | Katsutoshi Sekine | Japan | Nivolumab (Cohort 1) |
NSCLC | 87 | 4 weeks | OS; PFS; ORR | 54/33 | 8 | Retrospective | [22] |
| 2018 | Katsutoshi Sekine | Japan | Nivolumab (Cohort 2) |
NSCLC | 75 | 4 weeks | OS; PFS; ORR | 50/25 | 8 | Retrospective | [22] |
| 2018 | Takatsugu Ogata | Japan | Nivolumab | Gastric cancer | 26 | Two weeks after the first administration | OS; PFS; ORR | 19/7 | 6 | Retrospective | [38] |
| 2018 | Alona Zer | Canada | Anti-PD-L1 | NSCLC | 88 | 8 weeks | Change in NLR before and after treatment | 43/45 | 7 | Retrospective | [27] |
| 2018 | Malaka Ameratunga | The United Kingdom, Spain, and Australia | Anti-PD-1 and anti-PD-L1 | Advanced solid tumors | 165 | Each cycle of therapy | Change in NLR before and after treatment | 91/74 | 9 | Retrospective | [37] |
| 2018 | Wungki Park | USA | Nivolumab | NSCLC | 159 | Before the second nivolumab infusion | OS; PFS | 82/77 | 7 | Retrospective | [29] |
| 2018 | Monica Khunger | USA | Nivolumab | NSCLC | 109 | After 2 cycles of treatment | Change in NLR before and after treatment | 56/53 | 7 | Retrospective | [42] |
| 2019 | Mehmet A Bilen | USA | / | Melanoma, gastrointestinal cancer, lung/head and neck cancer, breast cancer, and others | 90 | 6 weeks | Change in NLR before and after treatment; OS; PFS | 53/37 | 8 | Retrospective | [44] |
| 2019 | Francesco Passiglia | Italy | Nivolumab | NSCLC | 45 | 6 weeks | OS | 32/13 | 7 | Retrospective | [34] |
| 2019 | Matthieu Dusselier | France | Nivolumab | NSCLC | 59 | The 4th nivolumab infusions | Change in NLR before and after treatment | 44/15 | 7 | Retrospective | [39] |
| 2020 | Arsela Prelaj | Italy | Nivolumab and pembrolizumab | NSCLC | 154 | The second cycle and third cycle | OS; PFS | 126/28 | 7 | Retrospective | [31] |
| 2020 | Kotaro Suzuki | Japan | Nivolumab | mRCC | 65 | 4 weeks | OS; PFS; ORR | 47/18 | 7 | Retrospective | [28] |
| 2020 | A Simonaggio | France | Nivolumab | mNSCLC and mRCC | 161 | 6 weeks | Change in NLR before and after treatment; OS; PFS | 114/47 | 9 | Retrospective | [54] |
| 2020 | Takuto Shimizu | Japan | Pembrolizumab | Metastatic urothelial carcinoma | 27 | 4 weeks | OS; PFS | 23/4 | 6 | Retrospective | [26] |
| 2020 | Yumiko Ota | Japan | Nivolumab | Gastric cancer | 98 | 4 weeks (PFS) and 8 weeks (OS) | OS; PFS | 68/30 | 7 | Retrospective | [23] |
| 2020 | Naotaka Nishiyama | Japan | Nivolumab | mRCC | 52 | 4 weeks | OS; PFS | 36/16 | 7 | Retrospective | [36] |
| 2020 | Lan Huang | China | Nivolumab, pembrolizumab, atezolizumab and ipilimumab | NSCLC | 61 | The fourth cycle of treatment | OS; PFS | 38/23 | 7 | Retrospective | [25] |
| 2020 | Tsutomu Namikawa | Japan | Nivolumab | Gastric cancer | 29 | 2 weeks, 4 weeks, 6 weeks, and 8 weeks | OS; PFS | 19/10 | 6 | Retrospective | [53] |
| 2020 | Daichi Tamura | Japan | Pembrolizumab | Urothelial carcinoma | 41 | 6 weeks | PFS | 29/12 | 6 | Retrospective | [46] |
| 2020 | Daiki Ikarashi | Japan | Nivolumab | mRCC | 45 | 6 weeks | Change in NLR before and after treatment | 30/15 | 6 | Retrospective | [32] |
| 2021 | Yin Tang | China | Anti-PD-1 and anti-PD-L1 | NSCLC | 124 | 6 weeks | OS; PFS; ORR | 89/35 | 8 | Retrospective | [30] |
| 2021 | Xianbin Wu | China | Anti-PD-1 | Esophageal squamous cell carcinoma | 119 | 6 weeks | Change in NLR before and after treatment; ORR | 102/17 | 7 | Retrospective | [41] |
| 2021 | Jeong Uk Lim | Korea | Nivolumab, pembrolizumab, and atezolizumab | NSCLC | 89 | 2 weeks | PFS | 62/27 | 7 | Retrospective | [18] |
| 2021 | Yuzhong Chen | China | Pembrolizumab, Sintilimab and Toripalimab | NSCLC | 151 | 6 weeks and 12 weeks | Change in NLR before and after treatment; OS; PFS; ORR | 115/36 | 8 | Retrospective | [20] |
| 2021 | Won-Mook Choi | Korea | Nivolumab | HCC | 194 | 2 weeks, 4 weeks, and 6 weeks | Change in NLR before and after treatment; OS; PFS | 159/35 | 8 | Retrospective | [33] |
| 2021 | Shixue Chen | China | Nivolumab, pembrolizumab, and others | NSCLC | 101 | 6 weeks | Change in NLR before and after treatment; OS; PFS; ORR | 72/29 | 8 | Retrospective | [47] |
| 2021 | Pei Yi Lee | Singapore | Nivolumab, pebrolizumab, atezolimumab, avelumab, durvalumab, and tremelimumab | Lung cancer, colorectal cancer, nasopharyngeal carcinoma, gastric cancer, hepatocellular carcinoma | 147 | 6 weeks | OS; PFS | 99/48 | 7 | Retrospective | [40] |
| 2021 | Jin Shang | China | Nivolumab, pembrolizumab, atezolimab, ipilimumab, and sintilimab | Pancreatic Cancer | 122 | After 2 doses | OS; PFS | 87/35 | 7 | Retrospective | [52] |
| 2021 | Qi Xiong | China | Nivolumab, pembrolizumab, atezolizumab, and toripalimab | SCLC | 41 | 6 weeks | Change in NLR before and after treatment; OS; PFS; ORR | 36/5 | 7 | Retrospective | [43] |
| 2021 | D Viñal | Spain | / | Lung cancer, melanoma, kidney cancer, bladder cancer, others | 211 | A treatment cycle | Change in NLR before and after treatment; OS; PFS | 136/75 | 7 | Retrospective | [48] |
| 2021 | Yoshiaki Yamamoto | Japan | Pembrolizumab | Urothelial carcinoma | 121 | 6 weeks | Change in NLR before and after treatment | 87/34 | 7 | Retrospective | [49] |
| 2021 | Jwa Hoon Kim | Korea | Nivolumab and pembrolizumab | Esophageal squamous cell carcinoma | 60 | A treatment cycle | OS; PFS | 56/4 | 7 | Retrospective | [50] |
| 2022 | Shaodi Wen | China | Pembrolizumab, sintilimab, toripalimab | NSCLC | 90 | 6 weeks and 12 weeks | Change in NLR before and after treatment; ORR | 69/21 | 7 | Retrospective | [19] |
| 2022 | Yusuke Murakami | Japan | Nivolumab | NSCLC | 162 | 4 weeks | Change in NLR before and after treatment; OS | 111/51 | 8 | Retrospective | [51] |
| 2022 | Lin Wang | China | Camrelizumab | Esophageal squamous cell carcinoma | 69 | 8 weeks | OS; PFS; ORR | 64/5 | 8 | Retrospective | [45] |
| 2022 | Jianming Xu | China | Sintilimab | Esophageal squamous cell carcinoma | 97 | 6 weeks | OS; PFS | 88/7 | 8 | Prospective | [24] |
| 2022 | Deniz Can Guven | Turkey | Nivolumab, atezolizumab, pembrolizumab, ipilimumab, and avelumab | RCC, melanoma, NSCLC and others | 231 | 4 weeks | OS; PFS | 155/76 | 7 | Retrospective | [8] |
Note. USA: United States of America; NSCLC: non-small-cell lung cancer; SCLC: small cell lung cancer; mNSCLC: metastatic non-small-cell lung cancer; RCC: renal cell carcinoma; mRCC: metastatic renal cell carcinoma; HCC: hepatocellular carcinoma; NLR: neutrophil-to-lymphocyte ratio; OS: overall survival; PFS: progression-free survival; ORR: objective response rate; PD-1: programmed cell death-1; PD-L1: programmed death ligand-1.