What do systematic reviews say?

Bevacizumab plus chemotherapy vs chemotherapy alone

Chemotherapy + bevacizumab showed no clear difference in severe adverse effects compared with chemotherapy (low certainty).

• Second‐line systemic therapy for metastatic colorectal cancer 2017 · Cochrane Headline outcomes only
  RR 1.07 [0.93, 1.25]
  4 studies · 1708 participants
  Low

Chemotherapy vs best supportive care

Chemotherapy probably leads to higher severe adverse effects compared with best supportive care (moderate certainty).

• Second‐line systemic therapy for metastatic colorectal cancer 2017 · Cochrane Headline outcomes only
  RR 1.19 [1.01, 1.4]
  1 study · 279 participants
  Moderate

FOLFOX + targeted therapy vs FOLFOX

FOLFOX + targeted therapy leads to higher severe adverse effects compared with FOLFOX (high certainty).

• Second‐line systemic therapy for metastatic colorectal cancer 2017 · Cochrane Headline outcomes only
  RR 1.2 [1.13, 1.28]
  2 studies · 1414 participants
  High

FOLFIRI + targeted therapy vs FOLFIRI

FOLFIRI + targeted therapy probably leads to higher severe adverse effects compared with FOLFIRI (moderate certainty).

• Second‐line systemic therapy for metastatic colorectal cancer 2017 · Cochrane Headline outcomes only
  RR 1.3 [1.17, 1.45]
  6 studies · 3341 participants
  Moderate

Modern chemotherapy regimens vs 5‐flourouracil

Modern chemotherapy regimens probably leads to higher severe adverse effects compared with 5‐flourouracil (moderate certainty).

• Second‐line systemic therapy for metastatic colorectal cancer 2017 · Cochrane Headline outcomes only
  RR 1.39 [1.22, 1.58]
  3 studies · 843 participants
  Moderate

Irinotecan + targeted therapy vs irinotecan

Irinotecan + targeted therapy leads to higher severe adverse effects compared with irinotecan (high certainty).

• Second‐line systemic therapy for metastatic colorectal cancer 2017 · Cochrane Headline outcomes only
  RR 1.44 [1.31, 1.59]
  2 studies · 1704 participants
  High

Immune‐enhancing supplements (oral or enteral) vs usual care or control

• Preoperative nutrition therapy in people undergoing gastrointestinal surgery 2024 · Cochrane Headline outcomes only
  no estimate extracted
  3 studies · 399 participants
  GRADE not reported

Oral nutritional supplements vs usual care or control

• Preoperative nutrition therapy in people undergoing gastrointestinal surgery 2024 · Cochrane Headline outcomes only
  no estimate extracted
  4 studies · 373 participants
  GRADE not reported

Preoperative parenteral nutrition vs usual care or control

• Preoperative nutrition therapy in people undergoing gastrointestinal surgery 2024 · Cochrane Headline outcomes only
  no estimate extracted
  3 studies · 260 participants
  GRADE not reported

Preoperative enteral nutrition (standard formula) vs usual care or control

• Preoperative nutrition therapy in people undergoing gastrointestinal surgery 2024 · Cochrane Headline outcomes only
  no estimate extracted
  1 study · 26 participants
  GRADE not reported

Irinotecan‐based regimens vs irinotecan

Irinotecan‐based regimens showed no clear difference in severe adverse effects compared with irinotecan (moderate certainty).

• Second‐line systemic therapy for metastatic colorectal cancer 2017 · Cochrane Headline outcomes only
  RR 1.18 [0.96, 1.45]
  6 studies · 2510 participants
  Moderate

Irinotecan + oxaliplatin vs irinotecan

Irinotecan + oxaliplatin probably leads to higher severe adverse effects compared with irinotecan (moderate certainty).

• Second‐line systemic therapy for metastatic colorectal cancer 2017 · Cochrane Headline outcomes only
  RR 1.22 [1.09, 1.37]
  1 study · 627 participants
  Moderate