title: Familial study of chronic lymphocytic leukemia: aggregation of different malignant processes in families with individuals affected with chronic lymphocytic leukemia.
abstract: There has been evidence that familial factors play a certain role in some cases of chronic lymphocytic leukemia. It is possible in one or more family members to observe chronic lymphocytic leukemia alone, other malignant disorders or combination of both of them.
  
  
  OBJECTIVE
  of our study was to analyze the association of family history of malignances with the onset of chronic lymphocytic leukemia.
  
  
  METHODS
  We conducted a case-control study through direct inquiry of the families of 126 patients with chronic lymphocytic leukemia. The control group consisted of 124 patients with benignant disorders. For statistic data processing we used Fisher's exact test in 2x2 table and Kaplan-Meier survival analyses.
  
  
  RESULTS
  35.71% of the investigated individuals had first degree relatives with malignant disorders, while in the control group their percentage was 17.7%. Significant correlation between positive family history of malignancy and the onset of chronic lymphocytic leukemia was found (P = 0.0016). The risk of development of chronic lymphocytic leukemia in individuals with family history of malignant disorders was 1.69 times higher than in individuals with negative family history RR = 1.697, 95% C.I. [1.177; 2.448]. There was no significant difference in the general survival between groups with positive and negative family history of malignancy. Stomach cancer was particularly often diagnosed in families with individuals affected with chronic lymphocytic leukemia. Other lymphoproliferative disorders were also registered in 3.9% of the families from the control group.
  
  
  CONCLUSIONS
  Our data show that there is a high risk of getting chronic lymphocytic leukemia in close relatives of affected individuals with malignant disorders. There was no data for greater aggressiveness of chronic lymphocytic leukemia in patients with positive family history of malignancy.
authors.affiliation: Department of Hematology, University Hospital St George, Medical University, Plovdiv, Bulgaria.
authors.forename: Ivanka S
authors.initials: IS
authors.lastname: Nenova
authors.forename: Istilian N
authors.initials: IN
authors.lastname: Karnolski
authors.forename: Nonka G
authors.initials: NG
authors.lastname: Mateva
authors.forename: Katya N
authors.initials: KN
authors.lastname: Sotirova
mesh_terms: D000293:Adolescent; D000328:Adult; D002031:Bulgaria / Q000453:epidemiology; D016022:Case-Control Studies; D002648:Child; D016000:Cluster Analysis; D005192:Family Health; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000175:diagnosis / Q000235:genetics* / Q000401:mortality; D008297:Male; D009369:Neoplasms / Q000453:epidemiology / Q000235:genetics*; D012307:Risk Factors; D015996:Survival Rate