Table 1. Characteristics of the included studies.
| Author | Year | Study design | Stage | Seg, n | Lob, n | Tumor size* (cm), seg vs. lob | Sex* (male/female), seg vs. lob | Age* (years), seg vs. lob | Blood loss* (mL), seg vs. lob | Operative time* (min), seg vs. lob | No. of lymph nodes harvested*, seg vs. lob | Postoperative morbidity*, seg vs. lob | 30- or 90-day mortality*, seg vs. lob | 5-year RFS, HR (seg vs. lob), 95% CI) | 5-year DFS, HR (seg vs. lob), 95% CI) | 5-year OS, HR (seg vs. lob), 95% CI) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Yamashita et al. (22) | 2012 | PM, RS | IA ≤2 cm | 76 | 72 | 1.5 [0.7–3.0] vs. 2.0 [0.9–3.0] | 41/49 vs. 73/51 | 69 [31–87] vs. 68 [50–90] | 132±181 vs. 202±437 | 257±91 vs. 276±82 | 12.1±9.4 vs. 21±9.1 | 17 (18.9) vs. 28 (22.6) | Not reported | – | 1.39 (0.28–7.02) | 1.49 (0.12–2.548) |
| IA >2 cm | 14 | 52 | 1.31 (0.43–4.01) | 1.28 (0.24–6.79) | ||||||||||||
| Deng et al. (16) | 2014 | PM, RS | IA ≤2 cm | 74 | 222 | – | 37/37 vs. 110/112 | 69.8±11.9 vs. 69.8±10.1 | Not reported | Not reported | Not reported | 68 (32.1) vs. 250 (39.3) | 1 (0.4) vs. 2 (0.3) | – | 1.72 (0.95–3.09) | 1.80 (0.96–3.38) |
| IA >2 cm | 31 | 93 | – | 17/14 vs. 48/45 | 71.5±8.1 vs. 71.4±7.7 | Not reported | Not reported | Not reported | 1.93 (0.99–3.77) | 1.92 (0.84–4.36) | ||||||
| Khullar et al. (15) | 2015 | PM, RS | IA ≤2 cm | 987 | 987 | 1.46±0.40 vs. 1.52±0.39 | – | – | Not reported | Not reported | Not reported | Not reported | 15 (1.55) vs. 16 (1.6) | Not reported | Not reported | 1.45 (1.10–1.91) |
| Kodama et al. (23) | 2016 | PM, RS | IA ≤2 cm | 69 | 69 | 1.5±0.4 vs. 1.67±0.3 | 33/36 vs. 32/37 | 62.6±7.81 vs. 62.1±9.52 | Not reported | Not reported | Not reported | Not reported | Not reported | 1.42 (0.24–8.28) | – | 0.69 (0.24–1.95) |
| Nishio et al. (25) | 2016 | PM, RS | IA ≤2 cm | 59 | 59 | 1.7 [1.3–1.8] vs. 1.7 [1.4–1.8] | 38/21 vs. 38/21 | 64 [58–71] vs. 61 [57–70.5] | 161±128 vs. 132±96 | 191±47 vs. 148±29 | Not reported | Not reported | Not reported | – | 1.65 (0.89–3.08) | 1.43 (0.64–3.20) |
| Koike et al. (24) | 2016 | PM, RS | IA ≤2 cm | 87 | 87 | 1.6 [0.6–2.0] vs. 1.6 [0.8–2.0] | 51/36 vs. 48/39 | 68 [42–83] vs. 68 [37-81] | Not reported | Not reported | 10±6 vs. 16±8 | Not reported | Not reported | – | 1.08 (0.63–1.88) | 0.99 (0.54–1.82) |
| Chan et al. (26) | 2020 | PM, RS | IA >2 cm | 90 | 90 | – | 44/46 vs. 132/147 | 71.5±8.6 vs. 68.8±9.1 | Not reported | Not reported | 10±1 vs. 18 ±1 | 23 (25.8) vs. 104 (37.3) | 1 (1.1), 2 (2.2) vs. 5 (1.8%), 6 (2.1) | 1.23 (0.82–1.85) | – | 1.23 (0.91–1.82) |
| Saji et al. (14) | 2022 | MRCT | IA ≤2 cm | 552 | 554 | 1.6 [0.6–2.0] vs. 1.6 [0.6–2.0] | 290/262 vs. 293/261 | 67 [32–83] vs. 67 [35–85] | 60±131 vs. 59±147 | 204±61 vs. 179±82 | 18±11 vs. 18±7 | 148 (26.8) vs. 142 (25.6) | Not reported | 0.998 (0.753–1.323) | – | 0.663 (0.474–0.927) |
| Shao et al. (17) | 2022 | PM, RS | IA >2 cm | 78 | 78 | – | 107/147 vs. 1,642/1,335 | – | Not reported | Not reported | Not reported | Not reported | Not reported | Not reported | Not reported | 1.578 (0.9865–2.525) |
| IA 1–2 cm | 138 | 138 | 1.895 (1.332–2.697) | |||||||||||||
| IA ≤1 cm | 36 | 36 | 1.287 (0.6264–2.644) | |||||||||||||
| Stamatis et al. (27) | 2022 | MRCT | IA ≤2 cm | 53 | 54 | 1.5 [0.5–2.5] vs. 1.5 [0.6–2.0] | 32/21 vs. 30/24 | 69 [42–80] vs. 66 [52–79] | Not reported | Not reported | Not reported | 7 (13.2) vs. 7 (13.0) | Not reported | – | 1.50 (0.60–3.76) | 0.61 (0.23–1.66) |
*, data are presented as median [range], mean ± SD, n, or n (%). Seg, segmentectomy; lob, lobectomy; RFS, recurrence-free survival; HR, hazard ratio; CI, confidence interval; DFS, disease-free survival; OS, overall survival; PM, propensity match; RS, retrospective study; MRCT, multicenter randomized controlled trial; SD, standard deviation.