## 3 Results  
Of 313 patients with malignant pleural mesothelioma, 216 were male (69.0%) and 97 were female (31.0%) (Table 1). The mean age at diagnosis of all subjects was 63.1 \(\pm\) 12.0 years. In terms of age distribution, 94 people (30.0%) were in their 70s, followed by 92 people in their 60s (29.4%), 71 people in their 50s (22.7%), and 42 people in their 40s (13.4%). The mean survival period after diagnosis was 21.7 \(\pm\) 33.0 months, and the median survival period was 8.0 months (95% confidence interval: 6.2-9.8). The 1-year, 2-year, and 5-year survival rates were 43.5%, 23.6%, and 12.5%, respectively. There were 159 cases of smoking history (50.8%) and 180 cases (57.5%) where asbestos exposure sources were occupational factors. However, 42.5% were non-occupational exposure. Among the subjects, 34.4% had surgery, and 71.6% had chemotherapy. The year of diagnosis was highest from 2011 to 2013 in 80 patients (25.6%), which coincided with when the Asbestos Injury Relief Act was enforced, and the lowest was from 2014 to 2016 with 32 patients (10.2%). Information on histological subtypes was available in 45.0% of patients. The most frequently observed subtype was epithelioid in 58.9%, sarcomatoid in 10.3%, biphasic in 13.7%, and NOS in 17.1% (Table 1). Table 2 compares the median survival period according to factors affecting 5-year survival. The median survival period according to age group was 12.0 months (95% confidence interval: 8.3 to 15.7) in the age group under 59 years old; 11.0 months (95% confidence interval: 6.3 to 15.7) in the age group 60-69 years, and 6.0 months (95% confidence interval: 4.7 to 7.2) in the age group 70 years and older. There was a statistically significant difference according to age group (\(p\) < 0.001). The median survival time according to the surgery and chemotherapy groups (\(n\) = 67) was more than higher than those in the surgical group (\(n\) = 28), in the chemotherapy group (\(n\) = 157), and non-surgical and non-chemotherapy group (\(n\) = 61), respectively. However, there was no significant difference in the median survival time according to sex, smoking history, occupational exposure to asbestos, and histological subtype. Figure 1: Flowchart showing the selection of study patients. \begin{table}
\begin{tabular}{l c} \hline \hline
**Variable** & **Malignant Pleural Mesothelioma (n = 313)** \\ \hline Sex & **5-Year Survival (Months)** \\ Male & **Median (95\% CI 1)** & _p-Value 2_ \\ Female & 97 (31.0) \\ Age(years) & 14 (4.5) \\ Mean \(\pm\) SD 1  & 63.1 \(\pm\) 12.0 \\ Median (95\% CI 2) & 64.0 (61.7, 64.4) \\ \textless{}50 & 42 (13.4) \\
50–59 & 71 (22.7) \\
60–69 & 92 (29.4) \\
70–79 & 94 (30.0) \\ \textgreater{}80 & 14 (4.5) \\ Survival duration(months) & \\ Mean \(\pm\) SD 1  & 21.7 \(\pm\) 33.0 \\ Median (95\% CI 2) & 8.0 (6.2, 9.8) \\ Overall survival (\% (95\% CI 2)) & \\
1 year & 43.5 (37.9, 49.0) \\
2 year & 23.6 (18.9, 28.4) \\
5 year & 12.5 (8.9, 16.1) \\ Smoking history & \\ No & 154 (49.2) \\ Yes & 159 (50.8) \\ Surgery & \\ No & 218 (69.6) \\ Yes & 95 (30.4) \\ Chemotherapy & \\ No & 89 (28.4) \\ Yes & 224 (71.6) \\ Year of diagnosis & \\
1997–2004 & 61 (19.5) \\
2005–2007 & 67 (21.4) \\
2008–2010 & 73 (23.3) \\
2011–2013 & 80 (25.6) \\
2014–2015 & 32 (10.2) \\ Occupational exposure & \\ No & 133 (42.5) \\ Yes & 180 (57.5) \\ Histological subtype & \\ Epitthleioid & 86 (58.9) \\ Sarcomatoid & 15 (10.3) \\ Biphasic & 20 (13.7) \\ NOS & 25 (17.1) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: General characteristics of the study subjects. \begin{table}
\begin{tabular}{l c c} \hline \hline  & \multicolumn{2}{c}{**Malignant Pleural Mesothelioma (n = 313)**} \\ \cline{2-3}
**Variable** & **n** & **5-Year Survival (Months)** \\  & **Median (95\% CI 1)** & _p-Value 2_ \\ \hline Total subjects & 313 & 8.0 (6.2, 9.8) \\ Sex & & \\ Male & 216 & 8.0 (6.2, 9.8) \\ Female & 97 & 9.0 (4.9, 13.1) \\ Age(years) & & \\ \hline \hline \end{tabular}
\end{table}