What would you like to understand today?
Cancer Explained turns trusted National Cancer Institute resources into clear, calm, plain-language learning — for patients, caregivers, families, and anyone who wants to understand cancer.
Where are you right now?
Choose what fits your situation and we’ll point you to the right place to start.
Explore by topic
Guided learning paths
Step-by-step reading paths — each step links to a plain-language explanation based on NCI resources.
“I've just been diagnosed.”
Start here to understand what cancer is, what your diagnosis and stage mean, and what comes next.
5 steps →
“I'm starting treatment.”
Understand your treatment options and how to prepare for and manage side effects.
5 steps →
“I'm caring for someone.”
Practical guidance for supporting someone with cancer — and for taking care of yourself too.
4 steps →
“I want to understand cancer.”
A grounding tour of what cancer is, what causes it, and how it's found and prevented.
5 steps →
“I'm interested in clinical trials.”
Understand what clinical trials are, how they work, and what joining one involves.
3 steps →
Start with the essentials
Diagnosis & Staging
Cancer Staging: What the Stage Means
A plain-language explanation of cancer staging, including the widely used TNM system and stage numbers, based on National Cancer Institute resources.
6 min read · Beginner
Clinical Trials
What Are Clinical Trials?
A plain-language explanation of what cancer clinical trials are, why they matter, and the main types, based on National Cancer Institute resources.
5 min read · Beginner
Cancer Basics
What Is Cancer?
A plain-language explanation of what cancer is, how cancer cells differ from normal cells, and how genetic changes cause cancer, based on National Cancer Institute resources.
8 min read · Beginner
Treatments
What Is Chemotherapy?
A plain-language explanation of how chemotherapy works, why it causes side effects, and what to expect, based on National Cancer Institute resources.
7 min read · Beginner
Treatments
What Is Immunotherapy?
A plain-language explanation of how immunotherapy helps the immune system fight cancer, based on National Cancer Institute resources.
7 min read · Beginner
Treatments
What Is Radiation Therapy?
A plain-language explanation of how radiation therapy works, the two main types, and what to expect, based on National Cancer Institute resources.
7 min read · Beginner
More ways we can help
Cancer in the News
When cancer makes headlines, we connect the moment to calm, NCI-grounded education.
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Send a Card
Free, gentle e-cards for treatment days, caregivers, remembrance, and more.
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Sleep, Rest & Comfort
Gentle breathing, rest for difficult nights, and a calming sleep soundscape.
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Cancer Explained is free for everyone. Donations help us keep creating calm, plain-language explanations based on trusted National Cancer Institute resources.
Built on trust
Evidence-based
Every explanation is based on National Cancer Institute educational resources, with links to the original.
Educational only
No medical advice, no diagnosis, no treatment recommendations — always talk with your healthcare team.
Free & accessible
Plain language, readable design, and accessibility built in from the start.