A Phase II Trial of 5-Fluorouracil, Leucovorin, and Oxaliplatin (mFOLFOX6) Chemotherapy Plus Bevacizumab for Patients With Unresectable Stage IV Colon Cancer and a Synchronous Asymptomatic Primary Tumor

Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically or cytologically confirmed adenocarcinoma of the colon

- No histological findings other than adenocarcinoma of the colon

- If the primary colon tumor and the metastatic lesions have been identified at
the same time and it is not possible to biopsy the colonic lesion, the patient
will be eligible without histologic confirmation of the primary cancer of the
colon as long as other radiographic studies or scans document the
characteristics of a colon cancer AND the biopsy of a metastatic site confirms
diagnosis of adenocarcinoma suggestive of a primary tumor of the colon

- Unresected primary tumor of the colon AND radiographically confirmed metastatic colon
cancer (single or multiple sites of metastases) that are not considered surgically
resectable for cure by chest imaging and CT scan or MRI of the abdomen within the
past 4 weeks and by endoscopy within the past 8 weeks

- Asymptomatic primary tumor

- No obstruction, perforation, or active bleeding requiring transfusion

- Distal extent of the tumor must be ≥ 12 cm from the anal verge on endoscopy

- Not a candidate for curative surgical resection of all metastatic and colon primary
tumors

- No evidence of Central Nervous System (CNS) metastases

- No recurrent local or metastatic disease after prior adjuvant therapy

- No diagnosis of rectal carcinoma

PATIENT CHARACTERISTICS:

- Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1

- Absolute neutrophil count ≥ 1200/mm³

- Platelet count ≥ 100,000/mm³

- Hemoglobin ≥ 9 g/dL

- Aspartate aminotransferase (AST) ≤ 2.5 times upper limit of normal (ULN) (≤ 5.0 times
ULN if liver metastases are present)

- Alkaline phosphatase ≤ 3.0 times ULN (≤ 5.0 times ULN if liver metastases are
present)

- Bilirubin ≤ 1.5 times ULN (≤ 2.0 times ULN if liver metastases are present)

- Creatinine < 1.8 mg/dL

- Urine dipstick indicating 0-1+ protein

- If dipstick reading is ≥ 2+, a 24-hour urine collection must demonstrate < 1 g
of protein

- Prothrombin Time and International Normalized Ratio (PT/INR) ≤ 1.5 unless the patient
is on therapeutic doses of warfarin, in which case the following criteria must be
met:

- Patient must have an in-range INR (between 2 and 3) on a stable dose of warfarin

- Patient must not have active bleeding or a pathologic condition that is
associated with a high risk of bleeding

- Patients with a history of non-colorectal malignancies must be disease free for ≥ 5
years prior to study entry and be deemed at low risk for recurrence

- Patients with the following cancers are eligible if diagnosed and treated within the
past 5 years:

- Carcinoma in situ of the colon

- Melanoma in situ

- Basal cell or squamous cell carcinoma of the skin

- Carcinoma in situ of the cervix

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception during and for 3 months after the
completion of study therapy

- No uncontrolled blood pressure (BP), defined as BP > 150/100 mm Hg

- No nonmalignant systemic disease that would preclude any of the study therapy drugs,
compromise the safety of the patient, or inhibit the patient's ability to participate
in the study, including any of the following:

- New York Heart Association class III or IV cardiac disease

- Myocardial infarction within the past 6 months

- Unstable angina within the past 6 months

- Symptomatic arrhythmia

- No transient ischemic attack or cerebrovascular accident within the past 6 months

- No symptomatic peripheral vascular ischemia within the past 6 months

- No arterial thrombotic event within the past 6 months

- No gastroduodenal ulcer(s) determined by endoscopy to be active

- No gastrointestinal perforation within the past 12 months

- No serious or nonhealing wound, skin ulcer, or bone fracture

- No significant traumatic injury within the past 28 days

- No significant episodes of acute bleeding requiring blood transfusion within the past
6 months

- No clinically significant (≥ grade 2) peripheral neuropathy (neurosensory or
neuromotor toxicity)

- No pulmonary fibrosis or interstitial pneumonitis by chest x-ray

- No psychiatric or addictive disorders or other conditions that would preclude the
patient from meeting study requirements

PRIOR CONCURRENT THERAPY:

- See Disease Characteristics

- No prior systemic chemotherapy, radiation therapy, or surgery for this malignancy

- No prior endoscopic management of this malignancy other than biopsy, including
endoscopic stent placement, fulguration, or laser treatment

- More than 30 days since prior investigational drugs

- More than 28 days since prior major surgical procedure or open biopsy

- More than 7 days since prior core biopsy or other minor procedure, excluding
placement of a vascular access device

- No concurrent major surgery unrelated to intact primary colon cancer

- No concurrent radiotherapy

- No concurrent filgrastim (G-CSF) or pegfilgrastim as primary prophylaxis for
neutropenia

- No concurrent halogenated antiviral agents

- No other concurrent investigational drugs

- No other concurrent antineoplastic agents