Lung cancer among native and foreign-born Swedes: histopathology, treatment, and survival

Lung cancer (LC) is the leading cause of cancer-related death worldwide, including Sweden. Several studies have shown that socioeconomic status affects the risk, treatment, and survival of LC. Due to immigration after Second World War, foreign-born people constitute 12.5% of the Swedish population. We wanted to investigate if there were any differences in LC management, treatment and survival among the foreign-born Swedes (FBS) compared to the native Swedish population (NatS) in Stockholm.

A retrospective analysis of all patients diagnosed with non-small cell lung cancer (NSCLC) at the Department of Respiratory Medicine and Allergy, Karolinska University Hospital, Solna from 1 January 2003 to 31 December 2008 was made. In all, 2041 cases of LC were diagnosed, thereof 1803 with NSCLC. Of these, 211 (11.7%) were FBS.

The mean age of NatS and FBS patients was 69.9 years, median 70 (range 26-96) and 66.0 years, median 66 (range 38-94), respectively (p < 0.001). In all, 89.8% of NatS and 90.0% of FBS were either smokers or former smokers. Adenocarcinoma was the most common subtype in both groups (NatS 54.7%, FBS 48.3%). In 140 (8.8%) of the NatS and 17 (8.1%) of the FBS the diagnosis was clinical only. There were no significant differences in stage at diagnosis, nor in performance status (PS) or different therapies between the groups. The median overall survival time for the NatS was 272 days and for FBS 328 days, again no significant difference. However, the median overall survival time for female NatS was 318 days and for female FBS 681 days (p = 0.002).

FBS patients were significantly younger than NatS at diagnosis, and female FBS lived longer than female NatS, but otherwise there were no significant differences between NatS and FBS patients with LC regarding diagnosis, treatment, and survival.