RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Aging may affect the way these drugs work.

PURPOSE: Phase I trial to determine the relationship between aging and the effectiveness of irinotecan in treating patients who have solid tumors.

OBJECTIVES:

• Determine whether there is a relationship between the pharmacokinetic characteristics of irinotecan and aging in patients with non-hematologic malignancies.
• Determine whether there is a relationship between the toxic effects of this drug and aging in these patients.
• Determine whether the relationship between genotype (UGT1A1, CYP3A, and other relevant genes) and phenotype (pharmacokinetics, toxicity) is affected by aging in these patients treated with this drug.
• Analyze data collected on the co-morbid conditions and concurrent medications in these patients treated with this drug.

OUTLINE: This is a multicenter study. Patients are stratified according to age (18 to 55 vs 70 and over).

Patients receive irinotecan IV over 90 minutes once weekly for 4 weeks. Treatment continues in the absence of disease progression or unacceptable toxicity.

Patients are followed for survival.

PROJECTED ACCRUAL: A total of 140 patients (70 per stratum) will be accrued for this study within 3.5 years.

DISEASE CHARACTERISTICS:

• Histologically confirmed non-hematologic malignancy
• Brain metastases or primary brain tumors are eligible provided patient is not receiving steroids or antiepileptic medications

PATIENT CHARACTERISTICS:

Age:

• 18 to 55 or 70 and over

Performance status:

• CTC 0-2

Life expectancy:

• Not specified

Hematopoietic:

• Granulocyte count at least 1,500/mm^3
• Platelet count at least 100,000/mm^3

Hepatic:

• Bilirubin no greater than upper limit of normal (ULN)
• SGOT no greater than ULN

Renal:

• Creatinine no greater than ULN

Other:

• Not pregnant or nursing
• Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY:

Biologic therapy:

• Not specified

Chemotherapy:

• At least 4 weeks since prior chemotherapy (6 weeks for nitrosourea)
• No more than 1 prior chemotherapy regimen for metastatic disease (no limit if administered in the adjuvant setting)
• No prior camptothecin

Endocrine therapy:

• See Disease Characteristics

Radiotherapy:

• At least 4 weeks since prior radiotherapy
• No concurrent radiotherapy, including for palliation

Surgery:

• At least 4 weeks since prior major surgery