What do systematic reviews say?

Delayed chemotherapy vs immediate chemotherapy

It is very uncertain whether delayed chemotherapy changes toxicity – diarrhoea compared with immediate chemotherapy (very low certainty).

• Survival differences with immediate versus delayed chemotherapy for asymptomatic incurable metastatic colorectal cancer 2018 · Cochrane Headline outcomes only
  RR 0.69 [0.34, 1.4]
  2 studies · 140 participants
  Very low