Irinotecan and Carboplatin in Treating Patients With Metastatic or Recurrent Small Cell Lung Cancer

DISEASE CHARACTERISTICS:

* Histologically or cytologically confirmed small cell lung cancer, meeting 1 of the following criteria:

  * Previously untreated metastatic or extensive disease

    * Malignant pleural effusion or multifocal lung disease is considered metastatic or extensive disease
    * Prior radiotherapy allowed
  * Recurrent disease

    * Limited, metastatic, or extensive disease
    * Relapsed after prior chemotherapy, excluding irinotecan hydrochloride

      * At least 90 days since prior chemotherapy
* Measurable disease, defined as ≥ 1 unidimensionally measurable lesion ≥ 1 cm by physical examination or radiographic techniques
* Known brain metastases allowed

PATIENT CHARACTERISTICS:

* ECOG performance status 0-2
* Life expectancy ≥ 3 months
* White Blood Cells \> 3,000/mm³
* Absolute neutrophil count ≥ 1,500/mm³
* Platelet count ≥ 100,000/mm³
* Hemoglobin ≥ 9.0 g/dL
* Bilirubin ≤ 1.5 mg/dL
* SGOT ≤ 2.5 times upper limit of normal (ULN) (5 times ULN if liver metastases present)
* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception during and for 3 months after completion of study treatment
* No medical disease that, in the opinion of the investigator, would preclude study treatment

PRIOR CONCURRENT THERAPY:

* See Disease Characteristics
* At least 10 days since prior radiotherapy (including brain)
* No prior irinotecan hydrochloride
* At least 2 weeks since prior and no concurrent anticonvulsants
* No concurrent radiotherapy