Imatinib in small cell lung cancer.
OBJECTIVE
To evaluate the clinical efficacy of Imatinib Mesylate in untreated or sensitive relapsed small cell lung carcinoma patients. Secondary endpoints included assessment of the safety and tolerance of Imatinib, and an analysis of KIT expression in tumor samples.


METHODS
Patients with previously untreated small cell lung cancer (SCLC) or with a sensitive relapse (one prior regimen with a sustained response for over 60 days) were eligible. Imatinib was delivered at 600 mg on a daily basis. Response was evaluated at 6 weeks using SWOG criteria.


RESULTS
As planned in the study design, a total of 19 patients were included in the trial (9 chemonaive patients with extensive disease and 10 sensitive relapse SCLC patients). No objective responses were observed with most previously untreated patients staying on study for less than 30 days. The median time to progression was 1 and 1.2 month in the untreated and sensitive relapse groups, respectively. Only 4 out of 19 tumor samples (21%) stained for KIT by means of immunohistochemistry.


CONCLUSIONS
No evidence of antitumor activity was observed in this small phase II trial including 19 SCLC patients treated with Imatinib Mesylate. KIT positivity in tumor samples appeared to be far less common than anticipated (21 vs. 70%). Future trials should include a screening procedure to evaluate KIT expression in SCLC samples. A better evaluation of KIT contribution to SCLC tumor progression needs to be achieved.
Soria
Jean-Charles
JC
Division of Medicine, Gustave Roussy Institute, 39 rue Camille Desmoulins, 94805, Villejuif, France. tle-che@igr.fr
Johnson
Bruce E
BE
Chevalier
Thierry Le
TL
D000284:Administration, Oral; D000368:Aged; D000970:Antineoplastic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D001549:Benzamides; D018288:Carcinoma, Small Cell / Q000188:drug therapy* / Q000473:pathology; D018450:Disease Progression; D005260:Female; D006801:Humans; D000068877:Imatinib Mesylate; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015513:Oncogene Proteins / Q000032:analysis / Q000096:biosynthesis; D010879:Piperazines / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors; D019009:Proto-Oncogene Proteins c-kit; D011743:Pyrimidines / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D016896:Treatment Outcome
D000970:Antineoplastic Agents; D001549:Benzamides; D015513:Oncogene Proteins; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D011505:Protein-Tyrosine Kinases; D019009:Proto-Oncogene Proteins c-kit