What do systematic reviews say?

Delayed chemotherapy vs immediate chemotherapy

• Survival differences with immediate versus delayed chemotherapy for asymptomatic incurable metastatic colorectal cancer 2018 · Cochrane Headline outcomes only
  no estimate extracted
  3 studies · 174 participants
  Low

Combination chemotherapy vs single‐agent chemotherapy

Combination chemotherapy leads to lower chemotherapy compliance compared with single‐agent chemotherapy (high certainty).

• Combination chemotherapy versus single‐agent chemotherapy during preoperative chemoradiation for resectable rectal… 2015 · Cochrane Headline outcomes only
  OR 0.36 [0.26, 0.52]
  2 studies · 1331 participants
  High

Platinum‐containing chemotherapy vs chemotherapy without platinum

Platinum‐containing chemotherapy leads to higher participants requiring chemotherapy delays compared with chemotherapy without platinum (high certainty).

• Platinum‐based chemotherapy for early triple‐negative breast cancer 2023 · Cochrane Headline outcomes only
  RR 2.23 [1.7, 2.94]
  5 studies · 1053 participants
  High

Chemotherapy vs chemotherapy alone

Chemotherapy showed no clear difference in overall survival (non‐taxane monotherapy vs taxane monotherapy) compared with chemotherapy (low certainty).

• Salvage systemic therapy for advanced gastric and oesophago‐gastric junction adenocarcinoma 2020 · Cochrane Headline outcomes only
  HR 1.13 [0.86, 1.48]
  1 study · 219 participants
  Low

Chemotherapy vs chemotherapy alone

Chemotherapy showed no clear difference in overall survival (taxane‐containing doublet therapy vs taxane… compared with chemotherapy (low certainty).

• Salvage systemic therapy for advanced gastric and oesophago‐gastric junction adenocarcinoma 2020 · Cochrane Headline outcomes only
  HR 1.05 [0.72, 1.54]
  2 studies · 121 participants
  Low

Chemotherapy vs chemotherapy alone

• Salvage systemic therapy for advanced gastric and oesophago‐gastric junction adenocarcinoma 2020 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 107 participants
  High

Chemotherapy vs chemotherapy alone

Chemotherapy showed no clear difference in progression‐free survival (non‐taxane monotherapy vs taxane… compared with chemotherapy (low certainty).

• Salvage systemic therapy for advanced gastric and oesophago‐gastric junction adenocarcinoma 2020 · Cochrane Headline outcomes only
  HR 1.14 [0.88, 1.48]
  1 study · 219 participants
  Low
• Salvage systemic therapy for advanced gastric and oesophago‐gastric junction adenocarcinoma 2020 · Cochrane Headline outcomes only
  HR 0.75 [0.52, 1.09]
  2 studies · 121 participants
  Low
• Salvage systemic therapy for advanced gastric and oesophago‐gastric junction adenocarcinoma 2020 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 107 participants
  High

Chemotherapy vs chemotherapy alone

• Salvage systemic therapy for advanced gastric and oesophago‐gastric junction adenocarcinoma 2020 · Cochrane Headline outcomes only
  no estimate extracted
  4 studies · 448 participants
  High

Chemotherapy vs chemotherapy alone

Chemotherapy showed no clear difference in tumour response rate (non‐taxane monotherapy vs taxane monotherapy) compared with chemotherapy (low certainty).

• Salvage systemic therapy for advanced gastric and oesophago‐gastric junction adenocarcinoma 2020 · Cochrane Headline outcomes only
  RR 0.65 [0.34, 1.26]
  1 study · 179 participants
  Low
• Salvage systemic therapy for advanced gastric and oesophago‐gastric junction adenocarcinoma 2020 · Cochrane Headline outcomes only
  RR 0.89 [0.48, 1.67]
  1 study · 107 participants
  Low

Chemotherapy vs chemotherapy alone

It is very uncertain whether chemotherapy changes tumour response rate (taxane‐containing doublet therapy vs taxane… compared with chemotherapy (very low certainty).

• Salvage systemic therapy for advanced gastric and oesophago‐gastric junction adenocarcinoma 2020 · Cochrane Headline outcomes only
  RR 1.47 [0.56, 3.89]
  2 studies · 121 participants
  Very low

Chemotherapy vs chemotherapy alone

• Salvage systemic therapy for advanced gastric and oesophago‐gastric junction adenocarcinoma 2020 · Cochrane Headline outcomes only
  no estimate extracted
  4 studies · 448 participants
  Moderate

Chemotherapy vs chemotherapy alone

• Salvage systemic therapy for advanced gastric and oesophago‐gastric junction adenocarcinoma 2020 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 70 participants
  Very low

Chemotherapy vs no chemotherapy

It is very uncertain whether chemotherapy changes mortality (at maximal compared with no chemotherapy (very low certainty).

• Management of people with intermediate‐stage hepatocellular carcinoma 2017 · Cochrane Headline outcomes only
  HR 0.85 [0.6, 1.18]
  2 studies · 412 participants
  Very low

Chemotherapy vs no chemotherapy

The review found no eligible studies for this question.

• Management of people with intermediate‐stage hepatocellular carcinoma 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Chemotherapy vs no chemotherapy

The review found no eligible studies for this question.

• Management of people with intermediate‐stage hepatocellular carcinoma 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Chemotherapy vs no chemotherapy

The review found no eligible studies for this question.

• Management of people with intermediate‐stage hepatocellular carcinoma 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Chemotherapy vs no chemotherapy

The review found no eligible studies for this question.

• Management of people with intermediate‐stage hepatocellular carcinoma 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Chemotherapy vs no chemotherapy

The review found no eligible studies for this question.

• Management of people with intermediate‐stage hepatocellular carcinoma 2017 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Chemotherapy vs Placebo

The review found no eligible studies for this question.

• Interventions for the treatment of oral cavity and oropharyngeal cancer: chemotherapy 2021 · Cochrane All outcomes
  Types of studies: it was anticipated that there would be no studies comparing chemotherapy with placebo (none were identified).
  0 studies
  No studies found

Chemotherapy vs best supportive care

Chemotherapy probably leads to lower overall survival compared with best supportive care (moderate certainty).

• Chemotherapy for advanced gastric cancer 2017 · Cochrane Headline outcomes only
  HR 0.37 [0.24, 0.55]
  3 studies · 184 participants
  Moderate