Multimorbidity: an issue of growing importance for oncologists.

As our population ages, more are afflicted with chronic conditions. Likewise, as more patients survive the diagnosis of cancer, they are likely to experience the sequelae of cancer treatment in the context of other coexisting medical conditions. Oncologists can expect that more than half of the patients they see who are older than 65 years will have at least one other meaningful chronic condition that may affect their treatment regimen. Multimorbidity can increase both treatment and illness burden and influence the benefit and burden of cancer treatment. Recognition of the impact of multiple co-occurring conditions on a patient's cancer care plan and development of strategies to address the challenges associated with multimorbidity will enable oncologists to provide higher quality, patient-centered care. Increased efforts should be focused on educating clinical providers to practice the collaborative, team-based care required by these patients. Finally, research is desperately needed to guide oncologists and other providers in the unique management issues presented by patients with multimorbidity.