|  | Univariate analysis |  | Multivariate analysis | ||
---|---|---|---|---|---|---|
 |  | Incidence of BM (%) |  |  |  |  |
Factors | 1-yr | 3-yr | 5-yr | P | P | RR (95 % CI) |
Gender | Â | Â | Â | Â | Â | Â |
Male | 7.6 | 20.5 | 26.9 | 0.012 | Â | Â |
Female | 13.3 | 33.4 | 43.0 | Â | Â | Â |
Age | Â | Â | Â | Â | Â | Â |
≤60 yrs | 14.1 | 28.8 | 37.9 | 0.035 |  |  |
>60 yrs | 3.9 | 19.3 | 24.9 |  |  |  |
Smoking History | Â | Â | Â | Â | Â | Â |
Negative | 11.7 | 28.6 | 37.9 | 0.038 | Â | Â |
Positive | 7.2 | 21.0 | 26.8 | Â | Â | Â |
Histology | Â | Â | Â | Â | Â | Â |
Non- squamous cell cancer | 12.0 | 34.6 | 44.3 | 0.000 | 0.001 | 4.13(1.86-9.19) |
Squamous cell cancer | 5.0 | 8.3 | 11.4 | Â | Â | Â |
Tumor stage | Â | Â | Â | Â | Â | Â |
T1 | 5.9 | 20.1 | 36.1 | 0.596 | Â | Â |
T2 | 8.3 | 22.6 | 30.1 | Â | Â | Â |
T3 | 14.4 | 36.9 | 36.9 | Â | Â | Â |
Laterality | Â | Â | Â | Â | Â | Â |
Left | 9.8 | 26.8 | 33.9 | 0.456 | Â | Â |
Right | 8.7 | 22.2 | 30.3 | Â | Â | Â |
Location | Â | Â | Â | Â | Â | Â |
Upper/middle lobe | 7.8 | 22.3 | 31.7 | 0.798 | Â | Â |
Lower lobe | 11.5 | 27.2 | 31.6 | Â | Â | Â |
Histologic grade | Â | Â | Â | Â | Â | Â |
Well/moderate | 8.8 | 21.7 | 31.1 | 0.601 | Â | Â |
Poor | 11.4 | 29.5 | 33.0 | Â | Â | Â |
Adjuvant chemotherapy | Â | Â | Â | Â | Â | Â |
No | 11.0 | 21.2 | 24.7 | 0.511 | Â | Â |
Yes | 8.5 | 25.1 | 33.8 | Â | Â | Â |
Postoperative radiotherapy | Â | Â | Â | Â | Â | Â |
No | 9.5 | 25.3 | 34.4 | 0.344 | Â | Â |
Yes | 8.7 | 23.0 | 29.0 | Â | Â | Â |
No. of metastatic lymphonodes | Â | Â | Â | Â | Â | Â |
≤5 | 4.6 | 13.3 | 20.9 | 0.000 |  |  |
>5 | 14.5 | 38.6 | 46.3 | Â | Â | Â |
LNR | Â | Â | Â | Â | Â | Â |
≥ 30 % | 15.3 | 39.2 | 46.4 | 0.000 | 0.000 | 3.33(1.79-6.18) |
< 30 % | 2.9 | 10.3 | 18.4 |  |  |  |
No. of metastatic mediastinal lymphonodes | Â | Â | Â | Â | Â | Â |
< 3 | 4.9 | 13.8 | 21.0 | 0.001 | Â | Â |
≥ 3 | 13.6 | 35.2 | 43.0 |  |  |  |
No. of metastatic mediastinal lymphonodes station | Â | Â | Â | Â | Â | Â |
1 | 6.0 | 14.8 | 21.8 | 0.000 | Â | Â |
2-4 | 15.1 | 42.7 | 51.6 | Â | Â | Â |
Ratio of metastatic mediastinal lymphonodes station | Â | Â | Â | Â | Â | Â |
≤50 % | 3.8 | 13.8 | 19.5 | 0.000 |  |  |
>50 % | 15.0 | 35.8 | 44.9 |  |  |  |