title: Prognostic factors in lung cancer in a defined geographical area over two decades with a special emphasis on gender.
abstract: BACKGROUND
  Many studies over recent decades report an increasing incidence of lung cancer in female patients. Female gender is often reported as a good prognostic factor.
  
  
  OBJECTIVE
  The aim of the present study was to investigate prognostic factors with a special emphasis on gender.
  
  
  METHODS
  During 1989-2008, 1497 patients in eastern Scania, a part of southern Sweden with 202,000 inhabitants, were referred to one Central Hospital and prospectively registered. All patients were grouped into four 5-year periods and were analysed for occurrence of lung cancer, patient performance status, types and stages of lung cancer and the relation to gender.
  
  
  RESULTS
  The incidence of lung cancer more than doubled in women. The proportion of adenocarcinomas increased in females and in males to 57% (P=0.028) and 42% (P=0.001), respectively, while the frequency of small cell lung carcinomas (SCLCs) decreased in both genders to approximately 14%. Females had significantly more frequent stage 1 (16.6%) and higher surgery rate (23.1%) than males (12% and 18.2%, respectively). Females showed a higher 5-year survival rate than males (20.1% and 11.5%, respectively; P<0.001). Patients with non-small cell lung carcinoma (NSCLC) had a higher 5-year survival rate than those with SCLC (16.5% and 7.5%, respectively; P<0.01); however, there was no significant survival difference in females between NSCLC and SCLC.
  
  
  CONCLUSIONS
  Female patients exhibited longer survival than males for both NSCLC and SCLC, and this was not explained by a higher frequency of stage 1 or surgery in NSCLC.
authors.affiliation: Department of Medicine, Central Hospital, Kristianstad, Sweden. gunnar.a.svensson@telia.com
authors.forename: Gunnar
authors.initials: G
authors.lastname: Svensson
authors.forename: Sven-Börje
authors.initials: SB
authors.lastname: Ewers
authors.forename: Ola
authors.initials: O
authors.lastname: Ohlsson
authors.forename: Håkan
authors.initials: H
authors.lastname: Olsson
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002276:Carcinoid Tumor / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D002294:Carcinoma, Squamous Cell / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D005260:Female; D006801:Humans; D015994:Incidence; D008175:Lung Neoplasms / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D012042:Registries / Q000706:statistics & numerical data; D012307:Risk Factors; D017678:Sex Distribution; D055752:Small Cell Lung Carcinoma / Q000401:mortality* / Q000473:pathology / Q000628:therapy; D013548:Sweden / Q000453:epidemiology