 This phase III trial studies the side effects and best dose of lenalidomide when given together with combination chemotherapy and to see how well they work in treating patients with newly diagnosed stage II-IV peripheral T-cell non-Hodgkins lymphoma. Drugs used in chemotherapy, such as cyclophosphamide, doxorubicin hydrochloride, vincristine sulfate, and etoposide, work in different ways to stop the growth of cancer cells, either by killing the cells, by stopping them from dividing, or by stopping them from spreading. Lenalidomide may stop the growth of peripheral T-cell non-Hodgkins lymphoma by blocking the growth of new blood vessels necessary for cancer growth. Giving combination chemotherapy with lenalidomide may be a better treatment for peripheral T-cell non-Hodgkins lymphoma. 