When to worry about blood in stool with gastrointestinal stromal tumour

A gastrointestinal stromal tumour can bleed into the digestive tract. The blood may be visible as red or maroon stool, or it may make stool black and tar-like. Slow bleeding may cause tiredness, breathlessness, paleness, or reduced exercise tolerance from anaemia. Bleeding can also arise from another bowel source, so the appearance and timing matter. A new change should be shared with the team managing your tumour rather than watched without advice.

Call your specialist or treatment team about any new, recurrent, or increasing blood. Record the colour, amount, timing, clots, bowel symptoms, pain, vomiting, and dizziness. Keep taking prescribed treatment unless your team instructs you otherwise, and ask before using aspirin, ibuprofen, or other medicines that may increase bleeding. Your clinicians may review blood counts and decide whether further examination or imaging is needed.

Go to an emergency department for heavy or continuous bleeding, black tar-like stool, clots, fainting, confusion, severe weakness, pale clammy skin, a racing heartbeat, severe abdominal pain, a swollen abdomen, repeated vomiting, or inability to pass stool or gas with worsening pain. These symptoms can indicate substantial bleeding or obstruction and need immediate assessment. Do not drive yourself if weak or dizzy.

Could the tumour be bleeding, or is another source more likely? Do I need a blood count or urgent scan? Should any treatment or medicine change? What symptoms should send me straight to emergency care, and whom should I call outside clinic hours?