Delays in cancer treatments have been responsible for adverse consequences on the final outcome. However, the exact effect of delayed cancer treatment on the risk of mortality is not clear. This study aims to examine the association between the delay in cancer treatment and the risk of mortality.

This systematic review and meta-analysis included 34 studies that included curative, neoadjuvant, and adjuvant indications for systematic treatment, radiotherapy, and surgery for cancers of rectum, lung, cervix, colon, head & neck, and breast. The delay in treatment and its consequences for all types of cancers were recorded. The primary outcome of the study was the overall survival for each 4-week delay in cancer treatment.

A total of 17 indications were found; however, no significant data on the effect of radiotherapy, and the effect on cervical cancer surgery was discovered. Out of 17 indicators, 13 suggested that a delay in cancer treatment was significantly associated with an increased risk of mortality. The hazard ratio for the mortality risk of each 4-week delay was 1.06-1.08.

The research concluded that cancer treatment delay was a major problem and was associated with a higher risk of mortality for all types of cancers.