What do systematic reviews say?

Heparin prophylaxis vs no prophylaxis

Heparin prophylaxis showed no clear difference in mortality compared with no prophylaxis (moderate certainty).

• Parenteral anticoagulation in ambulatory patients with cancer 2017 · Cochrane Headline outcomes only
  RR 0.98 [0.93, 1.03]
  18 studies · 9575 participants
  Moderate
• Parenteral anticoagulation in ambulatory patients with cancer 2017 · Cochrane Headline outcomes only
  RR 0.99 [0.96, 1.01]
  14 studies · 5229 participants
  Moderate

Heparin prophylaxis vs no prophylaxis

Heparin prophylaxis leads to lower symptomatic VTE compared with no prophylaxis (high certainty).

• Parenteral anticoagulation in ambulatory patients with cancer 2017 · Cochrane Headline outcomes only
  RR 0.56 [0.47, 0.68]
  16 studies · 9036 participants
  High

Heparin prophylaxis vs no prophylaxis

Heparin prophylaxis showed no clear difference in major bleeding compared with no prophylaxis (moderate certainty).

• Parenteral anticoagulation in ambulatory patients with cancer 2017 · Cochrane Headline outcomes only
  RR 1.3 [0.94, 1.79]
  18 studies · 9592 participants
  Moderate

Heparin prophylaxis vs no prophylaxis

Heparin prophylaxis leads to higher minor bleeding compared with no prophylaxis (high certainty).

• Parenteral anticoagulation in ambulatory patients with cancer 2017 · Cochrane Headline outcomes only
  RR 1.7 [1.13, 2.55]
  16 studies · 9245 participants
  High

Heparin prophylaxis vs no prophylaxis

Heparin prophylaxis showed no clear difference in thrombocytopenia compared with no prophylaxis (moderate certainty).

• Parenteral anticoagulation in ambulatory patients with cancer 2017 · Cochrane Headline outcomes only
  RR 0.69 [0.37, 1.27]
  12 studies · 5832 participants
  Moderate

Heparin prophylaxis vs no prophylaxis

• Parenteral anticoagulation in ambulatory patients with cancer 2017 · Cochrane Headline outcomes only
  no estimate extracted
  2 studies · 2241 participants
  Moderate

Low molecular weight heparin vs vitamin K antagonist secondary prophylaxis

Low molecular weight heparin secondary prophylaxis showed no clear difference in all‐cause mortality (main analysis ‐ active cancer) compared with vitamin K antagonist secondary prophylaxis (low certainty).

• Anticoagulation for the long‐term treatment of venous thromboembolism in people with cancer 2018 · Cochrane Headline outcomes only
  RR 0.99 [0.88, 1.12]
  4 studies · 1712 participants
  Low

Low molecular weight heparin vs vitamin K antagonist secondary prophylaxis

Low molecular weight heparin secondary prophylaxis showed no clear difference in all‐cause mortality (time‐to‐event) compared with vitamin K antagonist secondary prophylaxis (low certainty).

• Anticoagulation for the long‐term treatment of venous thromboembolism in people with cancer 2018 · Cochrane Headline outcomes only
  HR 0.94 [0.74, 1.2]
  2 studies · 1243 participants
  Low

Low molecular weight heparin vs vitamin K antagonist secondary prophylaxis

Low molecular weight heparin secondary prophylaxis probably leads to lower recurrent venous thromboembolism (main analysis ‐ active cancer) compared with vitamin K antagonist secondary prophylaxis (moderate certainty).

• Anticoagulation for the long‐term treatment of venous thromboembolism in people with cancer 2018 · Cochrane Headline outcomes only
  RR 0.59 [0.44, 0.8]
  4 studies · 1712 participants
  Moderate

Low molecular weight heparin vs vitamin K antagonist secondary prophylaxis

Low molecular weight heparin secondary prophylaxis probably leads to lower recurrent venous thromboembolism (time‐to‐event) compared with vitamin K antagonist secondary prophylaxis (moderate certainty).

• Anticoagulation for the long‐term treatment of venous thromboembolism in people with cancer 2018 · Cochrane Headline outcomes only
  HR 0.49 [0.31, 0.78]
  2 studies · 1243 participants
  Moderate

Low molecular weight heparin vs vitamin K antagonist secondary prophylaxis

Low molecular weight heparin secondary prophylaxis showed no clear difference in major bleeding (main analysis ‐ active cancer) compared with vitamin K antagonist secondary prophylaxis (low certainty).

• Anticoagulation for the long‐term treatment of venous thromboembolism in people with cancer 2018 · Cochrane Headline outcomes only
  RR 1.09 [0.55, 2.12]
  4 studies · 1712 participants
  Low

Low molecular weight heparin vs vitamin K antagonist secondary prophylaxis

It is very uncertain whether low molecular weight heparin secondary prophylaxis changes minor bleeding (main analysis ‐ active cancer) compared with vitamin K antagonist secondary prophylaxis (very low certainty).

• Anticoagulation for the long‐term treatment of venous thromboembolism in people with cancer 2018 · Cochrane Headline outcomes only
  RR 0.78 [0.47, 1.27]
  4 studies · 1712 participants
  Very low

Low molecular weight heparin vs vitamin K antagonist secondary prophylaxis

Low molecular weight heparin secondary prophylaxis showed no clear difference in thrombocytopenia (main analysis‐ active cancer) compared with vitamin K antagonist secondary prophylaxis (low certainty).

• Anticoagulation for the long‐term treatment of venous thromboembolism in people with cancer 2018 · Cochrane Headline outcomes only
  RR 0.94 [0.52, 1.69]
  1 study · 138 participants
  Low