The neutropenia/lymphopenia SIG focus on elucidating risk factors for- and outcomes of neutropenia and lymphopenia among patients treated with chemotherapy and/or radiotherapy for malignant disease.
Neutropenia is a frequent and sometimes fatal complication of chemotherapy. Close monitoring and prophylactic treatment can reduce mortality, but is also associated with inconvenience, risk of toxicity, infections with resistant microorganisms and increased costs. 
Radiotherapy can lead to severe and long-standing lymphopenia, but the risk factors for lymphopenia and its complications are not well elucidated. 
Although patients receive the same type of therapy, only some develop neutropenia or lymphopenia and only some of those develop infectious complications. The reasons for this variation in risk is poorly understood.
With routine methods an infectious pathogen can only be detected in a minority of patients who develop febrile neutropenia after chemotherapy and most patients receive empiric broad spectrum antibiotics. 
Therapy individualized according to risk stratification and novel diagnostic methods may improve patient outcomes.