This phase II trial studies the effect of duvelisib or CC-486 and usual chemotherapy consisting of cyclophosphamide, doxorubicin, vincristine, etoposide, and prednisone in treating patients with peripheral T-cell lymphoma. Duvelisib may stop the growth of cancer cells by blocking some of the enzymes needed for cell growth. Chemotherapy drugs, such as CC-486, cyclophosphamide, doxorubicin, vincristine, etoposide and prednisone, 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. This trial may help find out if this approach is better or worse than the usual approach for treating peripheral T-cell lymphoma.

This phase III trial tests whether continuous or intermittent zanubrutinib after achieving a complete remission (CR) with rituximab works in older adult patients with mantle cell lymphoma (MCL) who have not received treatment in the past (previously untreated). Rituximab is a monoclonal antibody that may interfere with the ability of cancer cells to grow and spread. Zanubrutinib may stop the growth of cancer cells by blocking some of the enzymes needed for cell growth. When zanubrutinib is used in MCL, the current standard of care is to continue administering the drug indefinitely until disease progression. This continuous treatment comes with clinical as well as financial toxicity, which could be especially detrimental in older patients. For patients who achieve a CR after initial zanubrutinib plus rituximab therapy, it may be safe and equally effective to stop treatment and restart zanubrutinib upon disease progression rather than continuing indefinitely in previously untreated older adult patients with MCL.

This phase II/III trial compares the side effects and activity of oral azacitidine in combination with the standard drug therapy (reduced dose rituximab-cyclophosphamide, doxorubicin, vincristine, and prednisone [R-miniCHOP]) versus R-miniCHOP alone in treating patients 75 years or older with newly diagnosed diffuse large B cell lymphoma. R-miniCHOP includes a monoclonal antibody (a type of protein), called rituximab, which attaches to the lymphoma cells and may help the immune system kill these cells. R-miniCHOP also includes prednisone which is an anti-inflammatory medication and a combination of 3 chemotherapy drugs, cyclophosphamide, doxorubicin, and vincristine. These 3 chemotherapy drugs, as well as oral azacitidine, 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. Combining oral azacitidine with R-miniCHOP may shrink the cancer or extend the time without disease symptoms coming back or extend patient's survival when compared to R-miniCHOP alone.