Since the early 1970s, incidence rates for non-Hodgkin’s lymphoma have nearly doubled. Incidence rates for Hodgkin’s disease have declined about 60%. Better means of diagnosis has also increased the number as doctors better understand cancer of lymphocytes verses other diseases.
Bleomycin falls into the anti-tumor antibiotic class- when it gets into the body it causes strands within the DNA of a cell to break, preventing it from dividing and leading to cell death. It does this to cancer cells and healthy cells. In a combination chemo regimen like ABVD, each drug attacks a cell's ability to divide in different ways; it's like bringing a knife, a stun gun, a baseball bat and some brass knuckles to a fight, but while that analogy probably lends itself to imagining another drug like bleomycin being introduced, it's not that easy. More likely a patient who's prone to pulmonary toxicity would be closely monitored on bleomycin, since that's a major side effect.