Phase I-II Study of Fluorouracil in Combination With Phenylbutyrate in Advanced Colorectal Cancer

Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Interferon-gamma may interfere with the growth of tumor cells and slow the growth of the tumor. Combining more than one drug with interferon-gamma may kill more tumor cells. This phase I/II trial is studying the side effects and best dose of giving fluorouracil together with phenylbutyrate, indomethacin, and interferon-gamma and to see how well it works in treating patients with stage IV colorectal cancer

PRIMARY OBJECTIVES:

I. To determine in a Phase I study the toxicity of flurouracil (FU) when given in escalating doses in combination with fixed doses of phenlylbutyrate (PB), indomethacin and recombinant human interferon-gamma (rhIFNg) to patients with advanced colorectal cancer.

II. To determine in a Phase II study the efficacy of FU in combination with PB, indomethacin and rhIFNg in patients with advanced colorectal cancer.

OUTLINE: This is a dose-escalation study of fluorouracil (5-FU).

Phase I: Patients receive 5-FU IV over 24 hours on day 1; phenylbutyrate IV over 120 hours and oral indomethacin daily on days 2-6; and interferon gamma subcutaneously on days 2, 4, and 6. Courses repeat weekly in the absence of disease progression or unacceptable toxicity.

Cohorts of 3-6 patients receive escalating doses of 5-FU until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose at which less than 2 of 6 patients experience dose-limiting toxicity (DLT).

Phase II :Patients receive 5-FU, phenylbutyrate, indomethacin, and interferon gamma as in phase I at the MTD.

Patients are followed for survival.

PROJECTED ACCRUAL: A maximum of 24 patients will be accrued for the phase I portion of this study and approximately 46 patients will be accrued for the phase II portion of this study.

Eligibility Criteria:
Inclusion Criteria:

* Stage IV colorectal adenocarcinoma, excluding brain metastases
* Histological confirmation of colorectal adenocarcinoma
* Previously untreated patients
* Previously treated patients

  * For the Phase I trial, no limitations
  * For the Phase II trial, previous treated limited to adjuvant radiation and/or chemotherapy which is completed at least 12 months before documentation of metastatic disease; patients may not have received chemotherapy for metastatic disease
* For the Phase I trial, patients may have measurable disease or unmeasurable disease; for the Phase II trial, patients must have measurable disease in at least two dimensions on x-rays, CT scan or MRI
* Expected survival of at least 16 weeks
* Performance status of \>= 70% (Karnofsky)
* WBC \>= 3000 uL
* Platelet count \>= 100,000/uL
* Bilirubin =\< 2 x ULN
* Creatinine =\< 2 x ULN
* Not pregnant and not lactating; women of child bearing age must have negative pregnancy test (beta-hcg)
* No allergies to interferon-gamma or E.coli derived products
* No serious medical intercurrent medical illnesses, including Class III or IV cardiovascular disease; patient may not be dependent on immunosuppressive drugs including corticosteroids, and may not receive these drugs for the entire duration of the study
* No diarrhea, and with adequate oral intake
* Patients of child-bearing age and potential must agree to use adequate birth control other than oral contraceptives for the entire duration of the study
* No previous or concurrent malignancy except inactive nonmelanoma skin cancer, in situ carcinoma of the cervix, grade 1 bladder cancer, or other cancers if the patient has been disease free for \>= 5 years
* Patients must be oriented and rational, and aware of the investigational nature of the study