Inclusion Criteria:

          -  Patients must weigh at least 10 kilograms at the time of the study enrollment.

          -  Diagnosis

        Newly diagnosed patients with histologically proven mature T- and NK- cell neoplasms:

        COHORT 1

          -  Aggressive NK cell leukemia (ICD-O code 9948/3)

          -  Extranodal NK/T-cell lymphoma, nasal type (ICD-O code 9719/3) COHORT 2

          -  Enteropathy-associated T-cell lymphoma (ICD-O code 9717/3)

          -  Hepatosplenic T-cell lymphoma (ICD-O code 9716/3)

          -  Peripheral T-cell lymphoma, non-otherwise specified (ICD-O code 9702/3)

          -  Angioimmunoblastic T-cell lymphoma (ICD-O code 9705/3)

          -  Other mature T- and NK-cell neoplasm histologies will considered after case-by-case
             discussion with Study Chairs and executive Vice-Chair Patients with lymphoma must have
             stage III or IV disease (See Appendix III for Staging).

               -  Organ Function Requirements

        Adequate liver function defined as:

          -  Total bilirubin ≤ 1.5 x upper limit of normal (ULN) for age.

          -  ALT (SGPT) < 3 x ULN for age.

        Adequate cardiac function defined as:

          -  Shortening fraction of ≥ 27% by echocardiogram, or

          -  Ejection fraction of ≥ 50% by radionuclide angiogram.

        Adequate pulmonary function defined as:

        • Patients with a history of pulmonary dysfunction must have no evidence of dyspnea at
        rest, no exercise intolerance due to pulmonary insufficiency, and a pulse oximetry > 92%
        while breathing room air unless current dysfunction is due to the lymphoma, in which case
        the patient is eligible.

        Exclusion Criteria:

          -  Alk+ or Alk- Anaplastic Large Cell Lymphoma (ALCL)

          -  Patients with active CNS disease.

          -  Patients with stage I or stage II disease (See Appendix III for Staging).

          -  Patients who have received any prior cytotoxic chemotherapy for the current diagnosis
             of NHL.

          -  Previous steroid treatment and/or radiation treatment are not allowed unless they are
             used for emergency management. Patients who have received emergency irradiation and/or
             steroid therapy will be eligible only if started on protocol therapy not more than one
             week from the start of radiotherapy or steroids.

          -  Female patients who are pregnant. Pregnancy tests must be obtained in girls who are
             post menarchal.

          -  Lactating females, unless they have agreed not to breastfeed their infants.

          -  Patients with Down syndrome.

          -  Patients taking CYP3A4 substrates with narrow therapeutic indices. Patients (COHORT 2
             ONLY) chronically receiving medications known to be metabolized by CYP3A4 and with
             narrow therapeutic indices (See Appendix V). The topical use of these medications (if
             applicable) is allowed.

          -  Patients taking CYP3A4 inhibitors. Patients (COHORT 2 ONLY) chronically receiving
             drugs that are known potent CYP3A4 inhibitors within 7 days prior to study enrollment
             (See Appendix V). The topical use of these medications (if applicable) is allowed.

          -  Patients taking CYP3A4 inducers. Patients (COHORT 2 ONLY) chronically receiving drugs
             that are known potent CYP3A4 inducers within 12 days prior to study enrollment (See
             Appendix V).