Study of Irinotecan and Docetaxel in Patients With Metastatic or Unresectable Gastric or Gastroesophageal Junction Adenocarcinoma

Inclusion Criteria:

* Patients must have clinically documented unresectable or metastatic gastric cancer or gastroesophageal adenocarcinoma and histologic confirmation of the diagnosis with tumor.
* Patients must have received one prior chemotherapeutic regimen for metastatic or unresectable disease. Patients may not have received prior therapy with irinotecan or a taxane.
* Tissue from tumor must be available. This may be paraffin embedded tissue from previous biopsy/resection or if it is not available, a repeat biopsy must be performed.
* Patients must agree to have a 20 cc blood sample drawn in addition to routine labs with each cycle of chemotherapy.
* Patients must have measurable disease by clinical exam or radiologic studies, that is at least one lesion measurable in at least one dimension, measuring 10 mm or more on a spiral CT scan, or at least 20 mm by an exam or a non-spiral scan. If prior radiation therapy was administered, measurable disease must be outside the radiation field.
* Patients must have a Zubrod performance status of 0-2.
* Patients must have a predicted life expectancy of at least 12 weeks.
* Patients must have:

  * a pre-treatment granulocyte count (i.e., segmented neutrophils + bands) of \>1,500/mm3,
  * a hemoglobin level of greater than or equal to 9.0 gm/dl, and
  * a platelet count of \>100,000/mm3.
* Patients must have adequate renal function as documented by a calculated creatinine clearance \> 60.
* Patients must have adequate hepatic function as documented by a serum bilirubin less than or equal to the institutional upper limit of normal, regardless of whether patients have liver involvement secondary to tumor.
* No major surgery within 1 month of starting study drug.
* Women of childbearing potential must have a negative pregnancy test.
* Peripheral neuropathy: must be \< grade 1

Exclusion Criteria:

* Patients may not have a history of an allergy to irinotecan.
* Patients with any active or uncontrolled infection, including known HIV infection.
* Patients with psychiatric disorders that would interfere with consent or follow-up.
* Patients with a history of myocardial infarction within the previous six months or congestive heart failure requiring therapy.
* Pregnant or lactating women. Men and women of reproductive potential may not participate unless they have agreed to use an effective contraceptive method while on treatment and for at least 3 months thereafter.
* Presence of clinically apparent central nervous system metastases or carcinomatous meningitis.
* Patients with a history of seizures are ineligible. Patients receiving phenytoin, phenobarbital, or other anti-epileptic prophylaxis are ineligible.
* Patients with any other severe concurrent disease, which in the judgment of the investigator would make the patient inappropriate for entry into this study.
* Patients with a history of severe hypersensitivity reaction to docetaxel or other drugs formulated with polysorbate 80.