What do systematic reviews say?

Delayed chemotherapy vs immediate chemotherapy

It is very uncertain whether delayed chemotherapy changes toxicity – nausea and vomiting 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 0.84 [0.31, 2.25]
  2 studies · 140 participants
  Very low