Table 1. Basic characteristics of included studies.
| Author (reference) | Country | Study period | Type of study | N | n | Age [year] | Follow-up [months] | DFI [months] | Median OS (months) | 5-year OS rate (%) | Prognostic factors, No. (%) |
|||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| DFI (<3 y) | Resection of meta* (incomplete) | No. of meta (>1) | HR of meta (negative) | |||||||||||
| Chen et al., 2009 (19) | Japan | 1991-2007 | Retrospective | 41 | 41 | 55 [35-81] | 25 [2-142] | 55 [0-192] | NR | 51 | 15 (36.6) | 0 (0) | 21 (51.2) | NR |
| Ludwig et al., 2003 (20) | Germany | 1989-1998 | Retrospective | 25 | 21 | 54 [35.3-77.3] | NR | 99.2 [13.4-165.8] | 96.9 | 53 | NR | 0 (0) | 9 (42.9) | NR |
| Yoshimoto et al., 2008 (21) | Japan | 1960-2000 | Retrospective | 90 | 90 | 55.1 [32-77] | 79.2 | 67.2 [0-244.8] | 75.6 | 54 | 33 (36.6) | 10 (11.1) | 12 (13.3) | NR |
| Lanza et al., 1992 (22) | USA | 1981-1990 | Retrospective | 44 | 37 | 55 [32-79] | NR | NR | 47 | 49.50 | NR | 0 (0) | 10 (27.0) | 15 (51.7) |
| Yhim et al., 2010 (12) | Korea | 1997-2007 | Retrospective | 45 | 15 | 49 [36-65] | 50 [5.0-136] | NR | NR | 82.10 | NR | 0 (0) | 4 (26.7) | 10 (66.7) |
| Meimarakis et al., 2013 (23) | Germany | 1982-2007 | Prospective | 81 | 81 | 58.2 [28.3-76.3] | NR | NR | NR | 59.60 | NR | 15 (18.5) | 30 (37.0) | 14 (31.1) |
| Welter et al., 2008 (24) | Germany | 1998-2007 | Retrospective | 47 | 47 | 55.0 [34.7-80] | 20.6 [3.2-110] | 44.4 [0-309.6] | 32 | 36 | 18 (38.3) | 14 (29.8) | 18 (38.3) | 25 (56.8) |
| Staren et al., 1992 (10) | USA | 1972-1990 | Retrospective | 63 | 33 | 50 | NR | 48 | 55 | 36 | NR | NR | 6 (18.2) | NR |
| McDonald et al., 1994 (25) | USA | 1982-1992 | Retrospective | 60 | 59 | 58 [21-81] | 42 [1-128.4] | 26.4 [1-247.2] | 42 | 37.80 | NR | 20 (33.9) | 28 (47.5) | NR |
| Simpson et al., 1997 (26) | Australia | 1984-1996 | Retrospective | 17 | 17 | 59 [40-74] | NR | 61.2 [8-218.4] | NR | 62 | 8 (47.1) | NR | 3 (18.8) | NR |
| Friedel et al., 2002 (27) | International | 1960-1994 | Retrospective | 467 | 467 | 53 [21-87] | 34 [0-240] | 43 | 35 | 35 | 181 (39.0) | 75 (16.1) | 148 (32.5) | NR |
| Tanaka et al., 2005 (28) | Japan | 1992-2001 | Retrospective | 52 | 39 | 53.7 [35-75] | NR | 66.8 [11.5-104.8] | 32 | 30.80 | NR | NR | 24 (61.5) | NR |
| Kycler and Laski, 2012 (29) | Poland | 1994-2002 | Retrospective | 33 | 33 | 53.4 [33-75] | 71.3 [0-232] | 51.9 | 73.2 | 54.50 | 16 (48.5) | 18(54.5) | 19 (57.6) | 20 (60.6) |
| Rena et al., 2007 (30) | Italy | 1990-2003 | Retrospective | 79 | 25 | 63 [42-82] | 43 [3-190] | NR | NR | 38 | 10 (40.0) | NR | NR | NR |
| Friedel et al., 1994 (31) | USA | 1979-1992 | Retrospective | 91 | 89 | 53 [23-78] | NR [2-144] | NR | 31 | 27 | NR | 21(23.6) | 28 (41.2) | 19 (57.6) |
| Planchard et al., 2004 (32) | France | 1972-1998 | Retrospective | 162 | 125 | 53 [30-82] | 102 [1-264] | 36 [2-252] | 50.4 | 45 | 65 (52.0) | 29(23.2) | 35 (28.0) | 25 (52.1) |
N, No. of patients; n, No. of analyzing survival and prognostic factors after pulmonary resection; median OS, median overall survival time after pulmonary metastasectomy; 5-year OS rate, 5-year overall survival rate; DFI, disease-free interval, between surgery for the primary tumor and the appearance of pulmonary metastases; meta, metastases; HR, hormone receptor, which includes estrogen receptor (ER) and progesterone receptor (PR), and only when both of them are negative, HR is negative; NR, no refer; *, complete resection was defined as no tumor cells at the surgical margin of the resected lung, which were examined macroscopically and histologically.