title: A phase II trial of imatinib mesylate in merkel cell carcinoma (neuroendocrine carcinoma of the skin): A Southwest Oncology Group study (S0331).
abstract: BACKGROUND
  Imatinib mesylate (Gleevec) was evaluated as a treatment for Merkel cell carcinoma (MCC, neuroendocrine carcinoma of the skin) based on the identification of strong c-KIT staining of these neoplasms.
  
  
  METHODS
  Eligibility included patients with measurable metastatic or unresectable MCC, c-KIT (CD117) expression and a Zubrod performance status of 0 to 2. Imatinib 400 mg daily was administered orally in 28-day cycles to 23 patients.
  
  
  RESULTS
  Overall, imatinib was well tolerated with grade 1 or 2 nausea, diarrhea, and hematologic toxicity as the most frequent side effects. A partial response was seen in 1 patient (4%; 95% CI: 0%-22%). Median progression-free survival was 1 month (95% CI: 1-2 months). Median overall survival was 5 months (95% CI: 2-8 months). One patient achieved a partial response and another had prolonged disease stabilization while receiving treatment.
  
  
  CONCLUSIONS
  The majority of patients progressed rapidly within 1 to 2 cycles of treatment. The observed progression-free survival and overall survival were not adequate to conclude that this agent was active in advanced MCC, and thus the planned second stage of patient accrual was not opened.
authors.affiliation: Nevada Cancer Institute, Las Vegas, USA.
authors.forename: Wolfram E
authors.initials: WE
authors.lastname: Samlowski
authors.forename: James
authors.initials: J
authors.lastname: Moon
authors.forename: Ralph J
authors.initials: RJ
authors.lastname: Tuthill
authors.forename: Michael C
authors.initials: MC
authors.lastname: Heinrich
authors.forename: Naomi S
authors.initials: NS
authors.lastname: Balzer-Haas
authors.forename: Stuart A
authors.initials: SA
authors.lastname: Merl
authors.forename: Ronald C
authors.initials: RC
authors.lastname: DeConti
authors.forename: John A
authors.initials: JA
authors.lastname: Thompson
authors.forename: Merle T
authors.initials: MT
authors.lastname: Witter
authors.forename: Lawrence E
authors.initials: LE
authors.lastname: Flaherty
authors.forename: Vernon K
authors.initials: VK
authors.lastname: Sondak
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001549:Benzamides; D015266:Carcinoma, Merkel Cell / Q000188:drug therapy*; D064420:Drug-Related Side Effects and Adverse Reactions; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D000068877:Imatinib Mesylate; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000009:adverse effects / Q000627:therapeutic use*; D047428:Protein Kinase Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D011743:Pyrimidines / Q000009:adverse effects / Q000627:therapeutic use*; D012878:Skin Neoplasms / Q000188:drug therapy*; D016019:Survival Analysis
chemical_list: D001549:Benzamides; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D011743:Pyrimidines; D000068877:Imatinib Mesylate