title: Does sex influence the impact that smoking, treatment interruption and impaired pulmonary function have on outcomes in limited stage small cell lung cancer treatment?
abstract: OBJECTIVE
  To look for survival differences between men and women with limited stage small cell lung cancer (LS-SCLC) by examining stratified variables that impair treatment efficacy.
  
  
  METHODS
  A retrospective review of 215 LS-SCLC patients treated from 1989 to 1999 with concurrent chemotherapy-radiotherapy modelled on the 'early-start' thoracic radiotherapy arm of a National Cancer Institute of Canada randomized trial.
  
  
  RESULTS
  Of 215 LS-SCLC patients, 126 (58.6%) were men and 89 (41.4%) were women. Smoking status during treatment for 186 patients (86.5%) was: 107 (58%) nonsmoking (NS) (76 [71%] male [M]; 31 [29%] female [F]) and 79 (42%) smoking (S) (36 M [46%]; 43 F [54%]) (continuing-to-smoke F versus M, P=0.001). Fifty-six patients (26%) had radiotherapy interruptions (RTI) during chemotherapy-radiotherapy because of toxicity. Radiotherapy breaks were not associated with sex (P=0.95). Survival by sex and smoking status at two years was: F + NS = 38.7%; F + S = 21.6%; M + NS = 22.9%; and M + S = 9.1% (P=0.0046). Survival by sex and RTI status at two years was: F + no RTI = 32.4%; F + RTI = 23.6%; M + no RTI = 23.0%; and M + RTI = 3.8% (P=0.0025). Diffusion capacity for carbon monoxide (DLCO) was recorded for 86 patients (40%) and median survival by sex and DLCO was F = 16.7 months and M = 12.1 months for a DLCO less than 60%; and for a DLCO 60% or more, F = 15.1 months and M = 15.3 months. First relapses were recorded in 132 cases (61%), with chest failure in men (45%) greater than for women (35%) and cranial failure rates similar between sexes (48%). Upon multivariable analysis, continued smoking was the strongest negative factor affecting survival.
  
  
  CONCLUSIONS
  In LS-SCLC, women overall do better than men, with or without a negative variable. The largest quantifiable improvement in survival for women came from smoking cessation, and for men from avoidance of breaks during treatment.
authors.affiliation: Dept. of Radiation Oncology, Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA. videtig@ccf.org
authors.forename: Gregory M M
authors.initials: GM
authors.lastname: Videtic
authors.forename: Pauline T
authors.initials: PT
authors.lastname: Truong
authors.forename: Robert B
authors.initials: RB
authors.lastname: Ash
authors.forename: Edward W
authors.initials: EW
authors.lastname: Yu
authors.forename: Walter I
authors.initials: WI
authors.lastname: Kocha
authors.forename: Mark D
authors.initials: MD
authors.lastname: Vincent
authors.forename: Anna T
authors.initials: AT
authors.lastname: Tomiak
authors.forename: A Rashid
authors.initials: AR
authors.lastname: Dar
authors.forename: Frances
authors.initials: F
authors.lastname: Whiston
authors.forename: Larry W
authors.initials: LW
authors.lastname: Stitt
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018288:Carcinoma, Small Cell / Q000188:drug therapy / Q000401:mortality* / Q000503:physiopathology / Q000532:radiotherapy; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000188:drug therapy / Q000401:mortality* / Q000503:physiopathology / Q000532:radiotherapy; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011879:Radiotherapy Dosage; D012189:Retrospective Studies; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology*; D016019:Survival Analysis