title: Unexpected rapid progression of metastatic adenoid cystic carcinoma during treatment with imatinib mesylate.
abstract: BACKGROUND
  There is a lack of effective treatment for metastatic adenoid cystic carcinoma (ACC), a usually indolent tumor. We studied the efficacy of imatinib mesylate, a potent inhibitor of KIT tyrosine kinase, in patients with KIT-positive metastatic ACC.
  
  
  METHODS
  Five patients with lung metastasis were treated in a pilot study with imatinib 400 mg by mouth twice a day. Mutations of c-kit and platelet-derived growth factor receptor (PDGFR)-alpha in tumors from these patients were analyzed.
  
  
  RESULTS
  Disease progression was noted in three of five patients during the short treatment periods, ranging from 2 to 3 weeks. Three patients died of disease within 6 months. No detectable mutations were found in c-kit and PDGFR-alpha.
  
  
  CONCLUSIONS
  We observed an unexpected high progression rate of metastatic ACC within short periods during imatinib treatment. Use of imatinib to treat cancers without c-kit or PDGFR-alpha mutation should be approached with caution.
authors.affiliation: Department of Oncology, National Taiwan University Hospital, National Taiwan University, No 7, Chung-Shan South Rd, Taipei 10016, Taiwan.
authors.forename: Ching-Hung
authors.initials: CH
authors.lastname: Lin
authors.forename: Roh-Fan
authors.initials: RF
authors.lastname: Yen
authors.forename: Yung-Ming
authors.initials: YM
authors.lastname: Jeng
authors.forename: Chin-Yuan
authors.initials: CY
authors.lastname: Tzen
authors.forename: Chiun
authors.initials: C
authors.lastname: Hsu
authors.forename: Ruey-Long
authors.initials: RL
authors.lastname: Hong
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000009:adverse effects*; D001549:Benzamides; D003528:Carcinoma, Adenoid Cystic / Q000188:drug therapy* / Q000235:genetics / Q000556:secondary; D004252:DNA Mutational Analysis; D018450:Disease Progression; D005260:Female; D006258:Head and Neck Neoplasms / Q000235:genetics / Q000473:pathology* / Q000628:therapy; D006801:Humans; D000068877:Imatinib Mesylate; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000556:secondary; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D010879:Piperazines / Q000008:administration & dosage / Q000009:adverse effects*; D016066:Pleural Effusion, Malignant / Q000473:pathology; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D011743:Pyrimidines / Q000008:administration & dosage / Q000009:adverse effects*
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D011505:Protein-Tyrosine Kinases