CHOP/Rituximab Followed by Maintenance PEG Intron in Treatment of Indolent/Follicular Non-Hodgkin's Lymphoma

Inclusion Criteria: 1. Patients with a diagnosis of advanced stage indolent non-Hodgkin's lymphoma expressing the CD20 surface antigen (as measured by immunohistochemistry or flow cytometry on peripheral blood, marrow, or tumor tissue). Specific histologic subtypes which are eligible include follicular small cleaved cell (follicular grade 1) and follicular mixed small cleaved and large cell (follicular grade 2) lymphoma, and small lymphocytic lymphoma. Patients with indolent follicular lymphoma (follicular grades 1 and with areas of diffuse histology and patients with diffuse follicle center cell lymphoma are eligible as long as the diffuse areas are not felt to represent areas of transformation to diffuse large B-cell lymphoma. 2. Patients with bulky stage II (at least one tumor mass \>/= 5 cm), or stage III or stage IV disease. 3. Patients with an expected life expectancy of at least 18 months. 4. Karnofsky Performance Status \>70 (ECOG 0, 1) 5. No prior anthracycline/anthracenedione-based chemotherapy (e.g., CHOP, CNOP) 6. No prior chemotherapy, immunotherapy, radiotherapy, or investigational therapies within three weeks of study entry. Steroid therapy is allowed only if required for maintenance of another chronic disease (e.g., rheumatoid arthritis) 7. Patients with newly diagnosed, relapsed, or refractory disease are eligible as long as they have symptoms or signs which require treatment in the opinion of the treating physician. 8. Patients must have at least one bi-dimensionally measurable lesion. 9. Patients aged \> 60 years, or patients with a history of coronary artery disease, congestive heart failure, hypertension, diabetes, or hyperlipidemia must have an estimated ejection fraction \> 0.45 (45%) by MUGA or echocardiography, performed within two months of study entry. 10. Females of childbearing potential must have a negative serum pregnancy test prior to enrollment in the study. 11. Patients without evidence of severe organ dysfunction as determined within two weeks of study entry: Hemoglobin \> 8 g/dl; Absolute neutrophil count \> 1000/; platelets \> 100,000 Creatinine \< 2.0 mg/dl, Bilirubin \< 2.0 mg/dl; AST \< 3 x upper normal; ALP \< 3 x upper normal (if liver function abnormalities are felt to be due to hepatic involvement by lymphoma, bilirubin \< 6 mg/dl; AST \< 4 x upper normal; ALP \< 4 x upper normal will be accepted). 12. All patients will have a complete eye examination performed by an ophthalmologist at baseline. 14\. Patients with negative HBSAg are eligible. In the absence of HBSAg negative results, the following will apply: 1. Patients with positive HBSAg must be further evaluated for potential risk of hepatitis B reactivation (see baseline evaluations). If it is felt that the benefits of rituximab-based therapy outweigh the risks of Hepatitis B reactivation, the patient may be enrolled at the discretion of the investigator and will be referred to gastroenterology for evaluation and possible prophylactic therapy (see baseline evaluations) 2. If the patient requires immediate treatment prior to determination of HBSAg results, and the risk of lymphoma outweighs the potential risk of hepatitis B reactivation, the patient may be enrolled at the discretion of the investigator. Exclusion Criteria: 1. Active CNS lymphoma. 2. Uncontrolled/poorly controlled serious nonmalignant disease (e.g., uncontrolled diabetes mellitus, hypertension, angina, chronic obstructive pulmonary disease). 3. History of hypersensitivity to interferon-alpha. 4. Active uncontrolled infection. 5. History of any other malignancy (except for treated squamous cell or basal cell carcinoma of the skin, or cervical intra-epithelial neoplasia of the cervix) within the past five years. 6. New York Heart Association class III or IV heart disease 7. Myocardial infarction within the past six months. 8. Major surgery within the past month. 9. Diagnosis of deep vein thrombosis or pulmonary embolism within the past three months. 10. Females who are pregnant or lactating. 11. Females of childbearing age who are unwilling to use appropriate methods of contraception. 12. Active psychiatric conditions (e.g., untreated severe depression or psychosis). 13. Patients with known HIV infection. 14. Patients who are on another protocol involving non-FDA approved biologics or drugs. 15. Vulnerable subjects.