Hyperprogressive disease: A distinct pattern of progression to immune checkpoint inhibitors.

Hyperprogressive disease (HPD) is a novel pattern of progression attributed to immune checkpoint inhibitor (ICI) treatment and characterized by a dramatic tumor surge and poor survival. The concept of HPD is still controversial, while the definition varies widely across studies. Although HPD has been associated with multiple clinicopathological and molecular features, there is no biomarker to predict this detrimental effect of immunotherapy and the underlying mechanism remains unknown. The aim of this comprehensive review is to summarize current data on HPD and present the controversies and clinical care management challenges for oncologists treating patients with ICIs.