title: Histopathologic and immunohistochemical characterization of rash to human epidermal growth factor receptor 1 (HER1) and HER1/2 inhibitors in cancer patients.
abstract: OBJECTIVE
  Human epidermal growth factor receptor (HER) 1 and HER 1/2 inhibitors have shown benefit against a wide range of solid tumors. However, their use is associated with rash in 40% to 90% of patients, which impacts quality of life and interrupts antineoplastic therapy. The pathologic characteristics of affected skin remain unclear, precluding development of rational therapies. The aim of this study was to evaluate differences in histologic and immunohistochemical alterations in rash caused by lapatinib, a dual HER1/2 inhibitor (HER1/2i), and the single HER1 inhibitors (HER1i) cetuximab, erlotinib, and panitumumab.
  
  
  METHODS
  For each of the four drugs, skin biopsies were collected and analyzed from 8 patients with rash (n = 32). Blinded independent histologic analysis and automated measurement of 17 skin biomarkers involved in proliferation, differentiation, and inflammation were conducted.
  
  
  RESULTS
  Increased expression of pAKT and decreased dermal K16 and p27 for HER1/2i when compared with each of the HER1i were observed. In addition, decreased epidermal atrophy and follicular neutrophilic infiltrate were evidenced in the skin of patients on HER1/2i when compared with HER1i.
  
  
  CONCLUSIONS
  We found a lower inhibition of epidermal kinetics and decreased inflammation in HER1/2i-induced rash. These findings underscore differences in skin toxicity as related to specificity of HER blockade, concordant with clinical tolerability and decreased severity of skin toxicity seen with the HER1/2i lapatinib compared with the HER1 inhibitors cetuximab, erlotinib, and panitumumab.
authors: Department of Dermatology, Robert H. Lurie Comprehensive Cancer Center, Northwestern University, Chicago, IL, USA.
authors: Beatrice
authors: B
authors: Nardone
authors: Kimberly
authors: K
authors: Nicholson
authors: Marissa
authors: M
authors: Newman
authors: Joan
authors: J
authors: Guitart
authors: Pedram
authors: P
authors: Gerami
authors: Nicholas
authors: N
authors: Talarico
authors: Ximing J
authors: XJ
authors: Yang
authors: Alfred
authors: A
authors: Rademaker
authors: Dennis P
authors: DP
authors: West
authors: Mario E
authors: ME
authors: Lacouture
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000911:Antibodies, Monoclonal / Q000009:adverse effects / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized; D001284:Atrophy; D000068818:Cetuximab; D066246:ErbB Receptors / Q000037:antagonists & inhibitors; D000069347:Erlotinib Hydrochloride; D005076:Exanthema / Q000139:chemically induced*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D053536:Keratin-16 / Q000378:metabolism; D000077341:Lapatinib; D008297:Male; D008875:Middle Aged; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D009369:Neoplasms / Q000188:drug therapy*; D000077544:Panitumumab; D047428:Protein Kinase Inhibitors / Q000009:adverse effects* / Q000627:therapeutic use; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D011799:Quinazolines / Q000009:adverse effects / Q000627:therapeutic use; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors; D012867:Skin / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D055815:Young Adult
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000068818:Cetuximab; D066246:ErbB Receptors; D000069347:Erlotinib Hydrochloride; D053536:Keratin-16; D000077341:Lapatinib; D048052:Mitogen-Activated Protein Kinase 3; D000077544:Panitumumab; D047428:Protein Kinase Inhibitors; D051057:Proto-Oncogene Proteins c-akt; D011799:Quinazolines; D018719:Erb-b2 Receptor Tyrosine Kinases; C512478:EGFR protein, human; C508053:ERBB2 protein, human