This study will assess the prophylactic effect of pegfilgrastim (Neulastim) on febrile and/or Grade IV neutropenia in participants receiving chemotherapy (CT) or immunochemotherapy (ICT) as first or second line treatment for NHL. Pegfilgrastim will be administered at a fixed dose of 6 milligrams (mg) subcutaneously 24 hours after the last dose of CT or ICT in each treatment cycle.