Delays in referral and diagnosis for chronic hematologic malignancies: a literature review.

To better understand the extent of diagnostic and referral delays from primary care providers (PCPs) for chronic hematologic malignancies, causes of these delays, and their possible effects on cancer outcomes, an extensive review of the literature was performed. Over 50 studies were reviewed, including many that concern delays in referral and diagnosis for solid tumors, as there was only sparse literature on delays specific to the liquid tumors. Delays for some chronic hematologic malignancies have been documented, mainly in centralized health care systems. Possible reasons for delays include PCPs' lack of exposure to hematologic malignancies, limited knowledge of associated signs and symptoms, and a reliance on patient symptoms to prompt referral (as opposed to signs and screening). Patient characteristics such as age, gender and race-ethnicity are also likely to play a role, although it is unclear if these exert their effect primarily via patient or provider mechanisms. Unfortunately, the outcomes associated with such delays are largely unreported, possibly because delay is complex to define and difficult to measure.