The Prevalence and clinical characteristics of primary Sjogren’s syndrome patients with lung cancer: An analysis of ten cases in China and literature review

BACKGROUND: A retrospective analysis of clinical data from primary Sjogren's syndrome (pSS) patients with lung cancer was conducted in order to guide further clinical work. METHODS: From January 1993 to December 2010, 10 pSS patients with lung cancer were hospitalized at the Peking Union Medical College Hospital. One hundred and three pSS patients were recruited as the controls. Patients' clinical data was retrospectively analyzed. RESULT: The incidence rate of lung cancer in pSS patients was 0.477%. The duration from diagnosis of pSS to lung cancer in the 10 patients was 0.92∼42 years. The pSS patients with lung cancer were significantly older than those without lung cancer (60.8 ± 8.9 vs. 44.9 ± 12.1, P < 0.001). Eight of the pSS patients with lung cancer (80%) were female nonsmokers; five pSS patients with lung cancer (50%) had lung involvement, exhibiting diffuse parenchymal lung disease. Adenocarcinoma was the most common pathological type of lung cancer (90%). Tumor node metastasis staging of lung cancer included: four cases of Ib (40%), one case of IIIb (10%), four cases of IV (40%) and one case undetermined (10%). CONCLUSION: The incidence rate of lung cancer in pSS patients was higher with respect to the normal population. Physicians should closely observe lung cancer incidence during the pSS follow-up period. Adenocarcinoma was the most frequently seen lung cancer pathology in pSS patients. Clinical stages and individualized treatment for pSS patients with lung cancer should be carefully determined.