title: Risk factors for classical Kaposi's sarcoma.
abstract: BACKGROUND
  Classical Kaposi's sarcoma (KS) is a malignancy of lymphatic endothelial skin cells. Although all forms of KS are associated with the KS-associated herpesvirus (KSHV), classical KS occurs in a small fraction of KSHV-infected people. We sought to identify risk factors for classical KS in KSHV-infected individuals.
  
  
  METHODS
  Lifestyle and medical history data from case patients with biopsy-proven non-AIDS (non-acquired immunodeficiency syndrome) KS in Italy were compared by logistic regression analysis with data from population-based KSHV-seropositive control subjects of comparable age and sex. After KSHV immunofluorescence testing, randomly selected patients on the rosters of local physicians were identified as control subjects. Risk of KS was estimated by odds ratios (ORs) and 95% confidence intervals (CIs). All statistical tests were two-sided.
  
  
  RESULTS
  From April 13, 1998, through October 8, 2001, we enrolled 141 classical KS case patients and 192 KSHV-seropositive control subjects of similar age (mean = 72 years for case patients and 73 years for control subjects) and sex (30% female case patients and 35% female control subjects). The strongest association was a reduced risk of KS with cigarette smoking (OR = 0.25, 95% CI = 0.14 to 0.45). Cigarette smoking intensity and duration could be evaluated for men, among whom the risk for KS was inversely related to the amount of cumulative smoking (P(trend)<.001). KS risk decreased approximately 20% (OR = 0.81, 95% CI = 0.74 to 0.89) for each 10 pack-years reported, and it was decreased sevenfold (OR = 0.14, 95% CI = 0.07 to 0.30) with more than 40 pack-years. In multivariable analysis, a decreased KS risk was associated with smoking (OR = 0.23, 95% CI = 0.12 to 0.44); but an increased KS risk was associated with topical corticosteroid use (OR = 2.73, 95% CI = 1.35 to 5.51), infrequent bathing (OR = 1.85, 95% CI = 1.04 to 3.33), and a history of asthma (OR = 2.18, 95% CI = 0.95 to 4.97) or of allergy among men (OR = 2.59, 95% CI = 1.15 to 5.83) but not among women (OR = 0.09, 95% CI = 0.003 to 2.76). KS was not related to other exposures or illnesses examined.
  
  
  CONCLUSIONS
  Risk for classical KS was approximately fourfold lower in cigarette smokers, a result that requires confirmation by other studies. Identification of how smoking affects KS risk may lead to a better understanding of the pathogenesis of this malignancy and interventions for its prevention.
authors.affiliation: Viral Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD 20892, USA. goedertj@mail.nih.gov
authors.forename: James J
authors.initials: JJ
authors.lastname: Goedert
authors.forename: Francesco
authors.initials: F
authors.lastname: Vitale
authors.forename: Carmela
authors.initials: C
authors.lastname: Lauria
authors.forename: Diego
authors.initials: D
authors.lastname: Serraino
authors.forename: Mario
authors.initials: M
authors.lastname: Tamburini
authors.forename: Maurizio
authors.initials: M
authors.lastname: Montella
authors.forename: Angelo
authors.initials: A
authors.lastname: Messina
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Brown
authors.forename: Giovanni
authors.initials: G
authors.lastname: Rezza
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Gafà
authors.forename: Nino
authors.initials: N
authors.lastname: Romano
mesh_terms: D000287:Administration, Topical; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000893:Anti-Inflammatory Agents / Q000009:adverse effects; D000914:Antibodies, Viral / Q000097:blood; D001249:Asthma / Q000150:complications; D016022:Case-Control Studies; D016001:Confidence Intervals; D005260:Female; D005938:Glucocorticoids; D006566:Herpesviridae Infections / Q000821:virology; D019288:Herpesvirus 8, Human / Q000276:immunology / Q000302:isolation & purification*; D006801:Humans; D006920:Hygiene; D007558:Italy; D008019:Life Style; D008297:Male; D008487:Medical History Taking; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D012307:Risk Factors; D012514:Sarcoma, Kaposi / Q000209:etiology*; D012907:Smoking
chemical_list: D000893:Anti-Inflammatory Agents; D000914:Antibodies, Viral; D005938:Glucocorticoids