Aspirin in Oncology

Deep-dive guide to aspirin in oncology, including mechanisms, cancer-type evidence, dosing, safety, and immune relevance

Aspirin is one of the most credible repurposed drugs in oncology.

It matters because it sits at the overlap of inflammation, platelet biology, immune evasion, and metastatic spread.

The strongest current human signal is in PIK3CA-mutated colorectal cancer. One of the most important broader mechanisms is platelet TXA2 suppression.

At a glance

• What it is: A long-established NSAID that irreversibly inhibits platelet COX-1

• Why it matters: It can affect inflammation, platelet-assisted metastasis, and tumour-immune biology at the same time

• Best-supported use today: Investigational adjuvant use in PIK3CA-mutated colorectal cancer

• Most important mechanism page: Aspirin and Thromboxane A2 (TXA2)

• Main limitation: Bleeding risk remains real, and benefit is not uniform across cancer types

Start here

• Aspirin Overview

• Evidence Summary

• Anticancer Mechanisms

• Aspirin and Thromboxane A2 (TXA2)

• Aspirin-Like Compounds

What this hub covers

This hub is built to answer four practical questions:

• where aspirin has the best evidence

• how aspirin may work in cancer biology

• which cancer types have the strongest or weakest signals

• where safety, bleeding, and treatment-context limits matter most

Best-supported settings today

1. Biomarker-selected colorectal cancer

This is the clearest current human evidence base.

Low-dose aspirin now has serious clinical relevance in PIK3CA-mutated colorectal cancer.

2. Platelet-focused anti-metastatic biology

Aspirin is increasingly relevant as a platelet-directed tool, not just a general anti-inflammatory drug.

That is where TXA2, platelet shielding, and immune-evasion biology become central.

3. Selected prevention and adjunctive settings

Outside colorectal cancer, aspirin still sits mainly in the investigational range.

The logic may still be strong in selected settings, but it is not a general standard of care.

Key cautions

• Bleeding risk is the main practical limit

• Dose and duration change the interpretation

• Tumour type and biomarker status matter

• aspirin should be reviewed like a real medication, not a casual add-on

Jump to another Aspirin page

Core pages

• Aspirin Overview

• Evidence Summary

• Anticancer Mechanisms

• Aspirin-Like Compounds

• Evidence by Cancer Type

Mechanism deep dive

• Aspirin and Thromboxane A2 (TXA2)

Practical pages

• Pharmacokinetics & Dosing

• Safety & Interactions

• Immune Effects

• Sourcing Quality Aspirin

Cancer-type pages

• Colorectal Cancer

• Breast Cancer

• Gastric Cancer

• Lung Cancer

• Endometrial Cancer

• Ovarian Cancer

• Pancreatic Cancer

• Glioblastoma

• Osteosarcoma

• Prostate Cancer

• Liver Cancer (Hepatocellular Carcinoma)

• Melanoma

• Myelofibrosis

• Other Cancer Types

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This information is for education only. It is not medical advice, diagnosis, or treatment. Please speak with a qualified clinician before making changes to care, medication, or supplement use.

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