Alemtuzumab and Combination Chemotherapy in Treating Patients With Newly Diagnosed Stage II, Stage III, or Stage IV T-Cell Non-Hodgkin's Lymphoma

DISEASE CHARACTERISTICS:

* Histologically confirmed aggressive peripheral T-cell non-Hodgkin's lymphoma (NHL), including the following nodal or extranodal subtypes:

  * Nodal:

    * Angioimmunoblastic lymphadenopathy
    * ALK 1-negative anaplastic large cell NHL
    * Peripheral T-cell lymphoma not otherwise specified
  * Extranodal:

    * Hepatosplenic NHL
    * Enteropathy-associated NHL
    * Panniculitic NHL
* Stage II-IV disease
* Newly diagnosed, CD52+ disease
* Measurable or evaluable disease
* No known CNS involvement with lymphoma
* No nasal natural killer T-cell NHL

PATIENT CHARACTERISTICS:

* ECOG performance status 0-2
* Life expectancy \> 4 months
* Absolute neutrophil count ≥ 1,000/mm³\*
* Platelet count ≥ 75,000/mm³\*
* Hemoglobin ≥ 8.5 g/dL\*
* Bilirubin \< 2.0 mg/dL
* Alkaline phosphatase ≤ 2 times upper limit of normal (ULN)
* AST or ALT \< 2 times ULN
* Creatinine \< 1.5 mg/dL\*
* Not pregnant or nursing
* Negative pregnancy test
* Fertile patients must use effective contraception
* No known hypersensitivity to any of the study drugs
* No serious illnesses that would preclude compliance with study requirements
* No known HIV positivity
* No other preexisting immunodeficiency (e.g., post-organ transplant)
* No other malignancy within the past 5 years except cervical carcinoma in situ or nonmelanoma skin cancer NOTE: \*Unless directly attributable to NHL

PRIOR CONCURRENT THERAPY:

* No prior chemotherapy or radiotherapy

  * Up to 7 days of prednisone preceding initiation of chemotherapy allowed
* No other concurrent chemotherapy, radiotherapy, or immunotherapy
* No other concurrent corticosteroids except dexamethasone used as an antiemetic for a brief period