title: CA-SSR1 Polymorphism in Intron 1 of the EGFR Gene in Patients with Malignant Tumors Who Develop Acneiform Rash Associated with the Use of Cetuximab.
abstract: OBJECTIVE
  Epidermal growth factor receptor (EGFR) inhibitors are not equally effective in all cancer patients. One potential clinical factor that could help in selecting patients who may benefit from treatment with cetuximab is acneiform rash, which correlates with the clinical response to EGFR inhibitors. Some previous studies have suggested that the tendency to develop rash may depend on polymorphisms in the EGFR gene. In this investigation, the association of degree of CA dinucleotide polymorphism with skin rash and cetuximab therapy outcome was examined.
  
  
  METHODS
  The study included 60 patients treated with cetuximab. For each patient, the severity of acneiform rash was assessed, and the type of polymorphism was determined by genotyping. Associations between genotypes, the acneiform rash, and response to treatment were determined by using the chi-square test and Spearman's rank correlation. The cutoffs S≤17(CA), L>17(CA), n(CA)≤35, and n(CA)>35 were tested, as well as the sum of the two allele repetitions.
  
  
  RESULTS
  A correlation was found between body surface area covered by rash and the sum of the two allele repetitions (p=0.030). No statistically significant relationship between genotype and response to treatment was observed. However, in patients who have had partial remission, we noticed a higher incidence of polymorphism, with less CA dinucleotide repetitions and early onset of rash.
  
  
  CONCLUSIONS
  A correlation between genotype and severity of rash was observed. That is, the severity of rash decreased with an increased number of CA repetitions.
authors.affiliation: Department of Oncology, University of Warmia and Mazury, Olsztyn, Poland.
authors.forename: Tomasz
authors.initials: T
authors.lastname: Jarząbek
authors.forename: Monika
authors.initials: M
authors.lastname: Rucińska
authors.forename: Wojciech
authors.initials: W
authors.lastname: Rogowski
authors.forename: Marzena
authors.initials: M
authors.lastname: Lewandowska
authors.forename: Jerzy
authors.initials: J
authors.lastname: Tujakowski
authors.forename: Maja
authors.initials: M
authors.lastname: Habib
authors.forename: Anna
authors.initials: A
authors.lastname: Kowalczyk
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Byszek
authors.forename: Rafał
authors.initials: R
authors.lastname: Dziadziuszko
authors.forename: Sergiusz
authors.initials: S
authors.lastname: Nawrocki
mesh_terms: D017486:Acneiform Eruptions / Q000175:diagnosis / Q000209:etiology*; D000328:Adult; D000368:Aged; D000483:Alleles; D000970:Antineoplastic Agents / Q000009:adverse effects*; D000068818:Cetuximab / Q000009:adverse effects* / Q000627:therapeutic use; D018900:Dinucleotide Repeats; D066246:ErbB Receptors / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D007438:Introns; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications* / Q000188:drug therapy / Q000235:genetics*; D011110:Polymorphism, Genetic; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D000970:Antineoplastic Agents; D066246:ErbB Receptors; D000068818:Cetuximab