Survival rates for blood cancers — including lymphoma, myeloma and some types of leukaemia — have dramatically increased over the past decade, due in great part to novel treatment approaches including molecularly-targeted therapies and immunotherapies.

In contrast to traditional forms of treatment which were largely episodic and finite (i.e., a set number of cycles of intravenous chemotherapy), therapy for some haematological cancers may now be given continuously over years, or in some cases indefinitely.

However, a new Commission by The Lancet Haematology shows how current methods of reporting adverse events, focused on assessing a drug or regimen's safety, often fail to also appropriately identify important delayed, chronic or cumulative effects that can affect patients substantially.

The authors propose new approaches to evaluating and reporting adverse events to complement the current methods. These include expanding reporting beyond high grade, acute toxic side-effects, and capturing less severe but chronic side effects, and cumulative and late effects in a more standardised manner.

While short term side effects with some regimens might include nausea and vomitting occurring over a few days in a cycle, long term effects might include neuropathy which worsens over time with ongoing drug exposure and can persist even after therapy is complete, for example.

The Commission also examines streamlined approaches to identify unexpected side effects from stem cell transplantation and improved evaluation of late and long term side effects in survivors.