A phase II trial of imatinib mesylate in merkel cell carcinoma (neuroendocrine carcinoma of the skin): A Southwest Oncology Group study (S0331)

Am J Clin Oncol. 2010 Oct;33(5):495-9. doi: 10.1097/COC.0b013e3181b9cf04.

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.

Publication types

  • Clinical Trial, Phase II
  • Multicenter Study
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Benzamides
  • Carcinoma, Merkel Cell / drug therapy*
  • Drug-Related Side Effects and Adverse Reactions
  • Feasibility Studies
  • Female
  • Humans
  • Imatinib Mesylate
  • Male
  • Middle Aged
  • Piperazines / adverse effects
  • Piperazines / therapeutic use*
  • Protein Kinase Inhibitors / adverse effects
  • Protein Kinase Inhibitors / therapeutic use*
  • Pyrimidines / adverse effects
  • Pyrimidines / therapeutic use*
  • Skin Neoplasms / drug therapy*
  • Survival Analysis

Substances

  • Benzamides
  • Piperazines
  • Protein Kinase Inhibitors
  • Pyrimidines
  • Imatinib Mesylate