1Department of Radiation Oncology, Korea University Ansan Hospital, Korea University College of Medicine, Ansan, Korea
2Department of Radiation Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
3Department of Radiation Oncology, St. Vincent’s Hospital, College of Medicine, The Catholic University of Korea, Suwon, Korea
4Department of Radiation Oncology, Asan Medical Center, Ulsan University College of Medicine, Seoul, Korea
5Proton Therapy Center, Research Institute and Hospital, National Cancer Center, Goyang, Korea
6Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University College of Medicine, Seoul, Korea
7Department of Radiation Oncology, Seoul National University College of Medicine, Seoul, Korea
Copyright © 2022 by the Korean Cancer Association
This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
General information including the author, affiliation, year of publication, patient recruitment, type of study, target disease, and definition of oligometastasis.
Clinical data including the number of patients in each arm (LCT arm vs. control arm), target sites for LCT (e.g., metastatic or primary site), number of oligometastasis, treatment modality employed, OS, PFS, and adverse events of grade 3 or higher.
Ethical Statement
The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.
Author Contributions
Conceived and designed the analysis: Ahn YC, Chie EK, Lee JH, Kim YS, Suh YG, Kim KH, Rim CH, Cho WK.
Collected the data: Rim CH, Cho WK.
Contributed data or analysis tools: Ahn YC, Chie EK, Lee JH, Kim YS, Suh YG, Kim KH, Rim CH, Cho WK.
Performed the analysis: Rim CH
Wrote the paper: Rim CH, Cho WK, Ahn YC, Chie EK.
Conflicts of Interest
Yong Chan Ahn, the editor-in-chief of the Cancer Research and Treatment, was not involved in the editorial evaluation or decision to publish this article. All remaining authors have declared no conflicts of interest.
Author, target disease | Modality of LCT | No. | Control | No. | Grade ≥ 3 toxicity |
---|---|---|---|---|---|
Gomez, NSCLC [8] | RT or surgery & standard maintenance | 25 | Standard maintenance | 24 | 2 cases G3 esophagitis in LCT; 1 G3 fatigue and 1 G3 anemia cases in control |
Ni, NSCLC [35] | TKI & MWA | 34 | TKI | 52 | 4 (9.3%) of MWA group needed chest tube drainage No G ≥ 3 toxicity related to TKI |
Shang, NSCLC [42] (postop) | RT or RFA and/or CTx | 105 | CTx or BSC | 47 | Overall: 24.8% vs. 21.2% (LCT vs. control) (most common complication was myelosuppression) 1 case (0.9%) G5 infection in LCT arm |
Wang, NSCLC [67] | RT (one site only) & ICI | 59 | ICI | 93 | 9 of 59 (15%); mostly pneumonia or BM toxicity; 1 G5 mortality case due to severe pneumonia in LCT arm |
Iyengar, NSCLC [32] | SBRT & CTx | 14 | CTx | 15 | Total 4 (28.6%) and 3 (20%) cases at LCT and control; no G5 toxicity |
Wang, NSCLC [68] | 125I brachy | 25 | CTx | 28 | ≥ G3 complication is lower in LCT arm (8%, pneumothorax vs. 25%, hematologic & nausea/vomiting) |
Gore, SCLC [28] | PCI and cRT (45 Gy/15 F) | 44 | PCI | 42 | Overall: 25% vs. 9.5% 1 case of G5 pneumonitis in LCT arm |
Bouman-Wammes, prostate [20] | SBRT (mostly 30 Gy/3 F or 35 Gy/7 F) | 43 | Active surveillance | 20 | No SBRT related toxicity |
Ost, prostate [36] | SBRT (81%) or resection | 31 | Active surveillance | 31 | No grade 2 or higher toxicity in LCT arm |
Parker, prostate [38] | RT and ADT | 410 | ADT | 409 | No data in low metastatic burden subgroup; 4% vs. 1% for whole population |
Tsumura, prostate [46] | RT to metastases, prostate brachy & HTx | 22 | Prostate brachy & HTx | 18 | No difference in grade ≥ 2 toxicity |
Phillips, prostate [6] | SBRT 24–48 Gy/3–5 F | 36 | Observation (allow CTx or ADT after 6 mo) | 18 | No G3 or higher adverse event in both arms |
Ruo, colorectal [40] | Bowel surgery and CTx | 127 | CTx (83.5%) | 103 | Grade 5 cases (2 postoperative cases, 1.6%) postop OP morbidity (20.5%) |
Ji, pancreas [56] | SBRT (m 41 Gy/5–7 F)+CTx | 23 | CTx | 23 | 1 case of G3 duodenal bleeding in LCT arm |
Shao, pancreas [65] | Liver and pancreas surgery+CTx | 50 | Palliative surgery + CTx | 50 | Longer hospital stay (21 vs. 13 days, p < 0.001), more transfusion and OP time in LCT arm |
Chen, esophagus [22] | CCRT (IMRT, 50 Gy/25 F to primary; 45 Gy/15 F to metastases; cisplatin/paclitaxel) | 196 | CTx | 265 | No significant difference in both arms |
Li J, esophagus [61] | IMRT (60 Gy) and/or CTx | 55 | CTx (90%), BSC (10%) | 27 | G3 complication: 7.3% (LCT) vs. 11.1% (control) No G4 or 5 toxicity in both arms |
Kim K, HCC [58] | Surgery, RT and/or CTx | 36 | CTx | 22 | 1 case of G3 pneumonitis after surgery |
Palma, multiple [7] | SBRT and/or standard CTx | 66 | CTx | 33 | More in LCT (10.6% vs. 3%) grade 5 cases due to SBRT |
Hu, multiple [55] | RT (SBRT, WBRT) & CTx or HTx | 86 | CTx or HTx | 156 | G3 pneumonia 3 cases (3.5%) and G3 leukopenia 1 case (1.2%) in LCT arm |
ADT, androgen deprivation therapy; BM, bone marrow; BSC, best supportive care; CCRT, concurrent chemoradiation; cRT, chest radiotherapy; CTx, chemotherapy; HCC, hepatocellular carcinoma; HTx, hormone therapy; ICI, immune-checkpoint inhibitor; IMRT, intensity modulated radiation therapy; LCT, local consolidation therapy; MWA, microwave ablation; NSCLC, non-small cell lung cancer; OP, operation; PCI, prophylactic cranial irradiation; RFA, radiofrequency ablation; RT, radiotherapy; SBRT, stereotactic body radiotherapy; SCLC, small cell lung cancer; TKI, tyrosine kinase inhibitor.
Pooled analyses of studies
No. of studies | No. of patients | Heterogeneity p-value | I2 (%) | Heterogeneity | Pooled OR (95% CI) | p-value favoring LCT | |
---|---|---|---|---|---|---|---|
Overall survival | |||||||
All studies | 48 | 6,759 | < 0.001 | 50.6 | Moderate | 2.896 (2.337–3.528) | < 0.001 |
Reliable comparability | 15 | 2,690 | 0.007 | 53.4 | Moderate | 2.548 (1.808–3.591) | < 0.001 |
RCTs only | 5 | 1,172 | 0.346 | 10.5 | Low | 1.535 (1.082–2.177) | 0.016 |
NSCLC | 17 | 1,525 | 0.06 | 37.5 | Low to moderate | 2.928 (2.151–3.985) | < 0.001 |
SCLC | 2 | 130 | 0.184 | 43.2 | Moderate | 1.043 (0.336–3.240) | 0.942 |
Prostate | 6 | 2,055 | 0.2 | 31.4 | Low to moderate | 1.941 (1.282–2.938) | 0.002 |
Colorectal | 4 | 914 | 0.016 | 70.9 | Moderate to high | 4.453 (2.103–9.429) | < 0.001 |
HCC | 3 | 218 | 0.541 | ~0 | Very low | 4.436 (2.439–8.069) | < 0.001 |
Esophagus | 4 | 777 | 0.556 | ~0 | Very low | 2.092 (1.485–2.947) | < 0.001 |
Progression-free survival | |||||||
All studies | 39 | 5,021 | < 0.001 | 62.1 | Moderate to high | 3.045 (2.356–3.937) | < 0.001 |
Reliable comparability | 16 | 2,109 | 0.001 | 60.3 | Moderate to high | 2.656 (1.713–4.120) | < 0.001 |
RCTs only | 8 | 1,317 | 0.282 | 18.0 | Low | 1.668 (1.187–2.344) | 0.003 |
NSCLC | 13 | 1,277 | 0.049 | 43.0 | Moderate | 3.993 (2.262–5.087) | < 0.001 |
SCLC | 2 | 130 | 0.276 | 15.8 | Low | 1.654 (0.544–5.034) | 0.376 |
Prostate | 10 | 1,726 | 0.003 | 63.6 | Moderate to high | 2.278 (1.463–3.546) | < 0.001 |
Colorectal | 3 | 684 | 0.031 | 71.3 | Moderate to high | 4.911 (2.212–10.903) | < 0.001 |
HCC | 2 | 126 | 0.854 | ~0 | Very low | 7.974 (2.081–30.547) | 0.002 |
Esophagus | 2 | 675 | 0.016 | 82.8 | High | 2.895 (0.524–15.984) | 0.223 |
CI, confidence interval; HCC, hepatocellular carcinoma; LCT, local consolidative therapy; NSCLC, non-small cell lung cancer; OR, odds ratio; RCT, randomized controlled trial; SCLC, small cell lung cancer.
Pooled survival rates according to disease
No. of studies | No. of patients | LCT | Control | p-value | |
---|---|---|---|---|---|
Overall survival | |||||
NSCLC | |||||
1-Year OS | 17 | 1,539 | 84.1 (77.0–89.3) | 66.0 (54.0–76.2) | 0.004 |
2-Year OS | 16 | 1,387 | 60.5 (52.5–68.0) | 35.1 (26.3–45.0) | < 0.001 |
SCLC | |||||
1-Year OS | 2 | 130 | 60.7 (38.1–79.4) | 42.8 (14.7–76.4) | 0.411 |
Prostate | |||||
3-Year OS | 6 | 1,980 | 86.6 (65.0–95.7) | 77.3 (44.6–93.5) | 0.512 |
Colorectal | |||||
1-Year OS | 4 | 914 | 92.3 (67.9–98.6) | 73.2 (48.1–89.0) | 0.157 |
2-Year OS | 4 | 914 | 72.5 (33.7–93.2) | 40.5 (19.3–65.9) | 0.173 |
Esophagus | |||||
1-Year OS | 4 | 777 | 72.8 (68.0–77.2) | 59.0 (46.6–70.3) | 0.026 |
2-Year OS | 4 | 777 | 31.5 (22.6–42.0) | 18.0 (14.6–22.0) | 0.005 |
Pancreas | |||||
1-Year OS | 2 | 146 | 30.6 (21.1–42.1) | 6.9 (8–40.2) | 0.122 |
HCC | |||||
1-Year OS | 3 | 218 | 72.1 (51.8–86.1) | 36.7 (16.0–63.8) | 0.039 |
2-Year OS | 3 | 218 | 38.8 (13.1–72.7) | 18.4 (6.3–43.2) | 0.282 |
H&N | |||||
1-Year OS | 3 | 145 | 83.7 (58.9–94.8) | 67.3 (20.4–94.3) | 0.463 |
2-Year OS | 3 | 145 | 61.9 (41.1–79.1) | 40.8 (13.8–74.9) | 0.321 |
Progression-free survival | |||||
NSCLC | |||||
1-Year PFS | 13 | 1,291 | 60.3 (51.0–68.9) | 34.7 (26.2–44.3) | < 0.001 |
2-Year PFS | 10 | 1,036 | 32.1 (22.2–43.9) | 10.6 (5.7–19.0) | 0.001 |
SCLC | |||||
1-Year PFS | 2 | 130 | 30.9 (17.2–49.2) | 16.6 (8.0–31.3) | 0.159 |
Prostate | |||||
1-Year PFS | 8 | 1,324 | 71.7 (51.4–85.9) | 56.5 (30.7–79.2) | 0.344 |
2-Year PFS | 7 | 1,270 | 46.8 (26.0–68.7) | 30.3 (13.4–54.9) | 0.316 |
Colorectal | |||||
1-Year PFS | 3 | 684 | 68.1 (52.3–80.6) | 34.6 (19.7–53.3) | 0.007 |
2-Year PFS | 3 | 684 | 41.8 (31.5–53.0) | 12.2 (5.7–24.4) | 0.001 |
Esophagus | |||||
1-Year PFS | 2 | 675 | 33.7 (22.0–47.8) | 23.2 (19.2–27.8) | 0.108 |
2-Year PFS | 2 | 675 | 8.9 (2.6–26.4) | 1.4 (0.6–3.6) | 0.021 |
H&N | |||||
1-Year PFS | 2 | 98 | 69.6 (50.6–83.6) | 25.4 (3.1–78.1) | 0.133 |
2-Year PFS | 2 | 98 | 37.5 (14.4–68.1) | 12.4 (5.6–25.5) | 0.068 |
HCC, hepatocellular carcinoma; H&N, head and neck; LCT, local consolidative therapy; NSCLC, non-small cell lung cancer; OS, overall survival; PFS, progression-free survival; SCLC, small cell lung cancer.
Complication assessment
Author, target disease | Modality of LCT | No. | Control | No. | Grade ≥ 3 toxicity |
---|---|---|---|---|---|
Gomez, NSCLC [ |
RT or surgery & standard maintenance | 25 | Standard maintenance | 24 | 2 cases G3 esophagitis in LCT; 1 G3 fatigue and 1 G3 anemia cases in control |
Ni, NSCLC [ |
TKI & MWA | 34 | TKI | 52 | 4 (9.3%) of MWA group needed chest tube drainage No G ≥ 3 toxicity related to TKI |
Shang, NSCLC [ |
RT or RFA and/or CTx | 105 | CTx or BSC | 47 | Overall: 24.8% vs. 21.2% (LCT vs. control) (most common complication was myelosuppression) 1 case (0.9%) G5 infection in LCT arm |
Wang, NSCLC [ |
RT (one site only) & ICI | 59 | ICI | 93 | 9 of 59 (15%); mostly pneumonia or BM toxicity; 1 G5 mortality case due to severe pneumonia in LCT arm |
Iyengar, NSCLC [ |
SBRT & CTx | 14 | CTx | 15 | Total 4 (28.6%) and 3 (20%) cases at LCT and control; no G5 toxicity |
Wang, NSCLC [ |
125I brachy | 25 | CTx | 28 | ≥ G3 complication is lower in LCT arm (8%, pneumothorax vs. 25%, hematologic & nausea/vomiting) |
Gore, SCLC [ |
PCI and cRT (45 Gy/15 F) | 44 | PCI | 42 | Overall: 25% vs. 9.5% 1 case of G5 pneumonitis in LCT arm |
Bouman-Wammes, prostate [ |
SBRT (mostly 30 Gy/3 F or 35 Gy/7 F) | 43 | Active surveillance | 20 | No SBRT related toxicity |
Ost, prostate [ |
SBRT (81%) or resection | 31 | Active surveillance | 31 | No grade 2 or higher toxicity in LCT arm |
Parker, prostate [ |
RT and ADT | 410 | ADT | 409 | No data in low metastatic burden subgroup; 4% vs. 1% for whole population |
Tsumura, prostate [ |
RT to metastases, prostate brachy & HTx | 22 | Prostate brachy & HTx | 18 | No difference in grade ≥ 2 toxicity |
Phillips, prostate [ |
SBRT 24–48 Gy/3–5 F | 36 | Observation (allow CTx or ADT after 6 mo) | 18 | No G3 or higher adverse event in both arms |
Ruo, colorectal [ |
Bowel surgery and CTx | 127 | CTx (83.5%) | 103 | Grade 5 cases (2 postoperative cases, 1.6%) postop OP morbidity (20.5%) |
Ji, pancreas [ |
SBRT (m 41 Gy/5–7 F)+CTx | 23 | CTx | 23 | 1 case of G3 duodenal bleeding in LCT arm |
Shao, pancreas [ |
Liver and pancreas surgery+CTx | 50 | Palliative surgery + CTx | 50 | Longer hospital stay (21 vs. 13 days, p < 0.001), more transfusion and OP time in LCT arm |
Chen, esophagus [ |
CCRT (IMRT, 50 Gy/25 F to primary; 45 Gy/15 F to metastases; cisplatin/paclitaxel) | 196 | CTx | 265 | No significant difference in both arms |
Li J, esophagus [ |
IMRT (60 Gy) and/or CTx | 55 | CTx (90%), BSC (10%) | 27 | G3 complication: 7.3% (LCT) vs. 11.1% (control) No G4 or 5 toxicity in both arms |
Kim K, HCC [ |
Surgery, RT and/or CTx | 36 | CTx | 22 | 1 case of G3 pneumonitis after surgery |
Palma, multiple [ |
SBRT and/or standard CTx | 66 | CTx | 33 | More in LCT (10.6% vs. 3%) grade 5 cases due to SBRT |
Hu, multiple [ |
RT (SBRT, WBRT) & CTx or HTx | 86 | CTx or HTx | 156 | G3 pneumonia 3 cases (3.5%) and G3 leukopenia 1 case (1.2%) in LCT arm |
ADT, androgen deprivation therapy; BM, bone marrow; BSC, best supportive care; CCRT, concurrent chemoradiation; cRT, chest radiotherapy; CTx, chemotherapy; HCC, hepatocellular carcinoma; HTx, hormone therapy; ICI, immune-checkpoint inhibitor; IMRT, intensity modulated radiation therapy; LCT, local consolidation therapy; MWA, microwave ablation; NSCLC, non-small cell lung cancer; OP, operation; PCI, prophylactic cranial irradiation; RFA, radiofrequency ablation; RT, radiotherapy; SBRT, stereotactic body radiotherapy; SCLC, small cell lung cancer; TKI, tyrosine kinase inhibitor.
CI, confidence interval; HCC, hepatocellular carcinoma; LCT, local consolidative therapy; NSCLC, non-small cell lung cancer; OR, odds ratio; RCT, randomized controlled trial; SCLC, small cell lung cancer.
HCC, hepatocellular carcinoma; H&N, head and neck; LCT, local consolidative therapy; NSCLC, non-small cell lung cancer; OS, overall survival; PFS, progression-free survival; SCLC, small cell lung cancer.
ADT, androgen deprivation therapy; BM, bone marrow; BSC, best supportive care; CCRT, concurrent chemoradiation; cRT, chest radiotherapy; CTx, chemotherapy; HCC, hepatocellular carcinoma; HTx, hormone therapy; ICI, immune-checkpoint inhibitor; IMRT, intensity modulated radiation therapy; LCT, local consolidation therapy; MWA, microwave ablation; NSCLC, non-small cell lung cancer; OP, operation; PCI, prophylactic cranial irradiation; RFA, radiofrequency ablation; RT, radiotherapy; SBRT, stereotactic body radiotherapy; SCLC, small cell lung cancer; TKI, tyrosine kinase inhibitor.