The effect of smoking on the development of lung cancer in idiopathic interstitial pneumonia

对66例初诊为特发性间质性肺炎(IIP)的患者(男54例，女12例)进行了2~13年的前瞻性研究。同期调查了性别、吸烟史相匹配的慢性阻塞性肺疾病(COPD)患者的肺癌发病率。其中11例(16.7%)发生肺癌，明显高于COPD组(1/95，1%)(P&lt；除1例为男性吸烟者外，其余肺癌患者均为男性吸烟者。在临床表现上，与未发生肺癌的患者相比，IIP患者没有接受激素治疗和胸片体积缩小。在免疫组织化学研究中，我们验证了IIP肺癌患者存在生长因子旁分泌机制的假说。为了验证这一假说，对肺组织标本进行表皮生长因子(EGF)及其受体(EGF-R)染色，9例IIP(+)患者中2例EGF阳性，44例IIP(-)患者中23例EGF染色阳性。对于EGF-R，两组间无显著差异，提示IIP肺癌的生长可能存在旁分泌机制。

The incidence lung cancer in 66 patients (54 males and 12 females), who were originally diagnosed as having idiopathic interstitial pneumonia (IIP), was studied prospectively by following them 2 to 13 years.As controls, sex and smoking history matched patients with chronic obstructive pulmonary disease (COPD) were also surveyed for the same follow up period.Eleven patients with IIP (16,7%) developed lung cancer.This incidence was significantly higher than that of COPD (1 out of 95,1%) group (p<0.01), regardless of the higher mean age and mean observation period of COPD group.All lung cancer patients except one were male smokers.In clinical findings, IIP patients with lung cancer didn't have steroid treatment and volume decrease in chest roentogenogaram when compared with those who did not develop lung cancer.In the immunohistochemical study, we examined the hypothesis that there is a paracrine mechanism of growth factor in the lung cancer with IIP.To validate it, we stained lung specimen with Epidermal growth factor (EGF) and EGF-receptor (EGF-R).Two of 9 IIP (+) patients and 23 of 44 IIP (-) patients showed positive for EGF staining.In stroma cells, 5 of 9 IIP (+) patients and 6 out of 44 IIP (-) patients exhibited positive for EGF straining (p<0.05).For EGF-R,there weren't any significant difference between the two groups.These results suggest that there might exist paracrine mechanism in the growth of lung cancer with IIP.