Privacy policy

Information we collect

You can read most of Cancer Explained without giving us any personal information — we do not require an account. Depending on how you use the site, we may collect:

• Email address — if you subscribe to our newsletter or updates.
• Contact form submissions — the message and contact details you choose to send us.
• Donation information — details needed to process a gift, such as the amount and any dedication. Payment card details are handled by our payment provider, not by us (see below).
• Analytics — general information about how pages are used, so we can improve our educational content. We name the two tools we use, and what each one stores, in the Analytics section below.
• Cookies — we set one small cookie of our own, and only in the “Where in the World?” game. It is described in the Game progress cookie section below. Google Analytics sets one (see below), and you can decline it. Some tools remember your work using your browser’s local storage on your own device, which is not a cookie and is never sent to us.
• Questions you type into Ask — if you use the Ask feature, the question you type, which is sent to our server so it can look up matching passages on our own pages. It is not saved in a database and is not sent to an AI company. Please do not include sensitive personal or medical details.
• E-card and form details — if you send an e-card, the recipient’s email address and your message are used to send it through our email provider. Some forms use Cloudflare Turnstile, a spam check run by Cloudflare under its own privacy terms. To limit abuse, our servers keep short-lived request counters keyed to a one-way hash of your IP address; they expire automatically.

Donations and payments

Donation payments are processed by third-party payment providers. When you make a gift, your payment card information is collected and handled directly by that provider under its own privacy and security practices — National Cancer Information Foundation does not store your full card details.

How we use information

We use the limited information we collect to respond to you, send updates you asked for, process and acknowledge donations, keep the site secure, and improve our educational content. We do not sell your personal information, and we do not use your information to build advertising profiles, personalize ads to you, or retarget you elsewhere on the web. As described below, anonymous, aggregate counts of which features are used — never anything you typed or any identifier — do reach a Google-Ads-linked analytics property, because we participate in the Google Ad Grants nonprofit program, which requires reporting at least one conversion signal a month to keep the grant.

Analytics

We want to know which pages actually help people, so we can write more of what works. We use two tools, and they are different from each other in a way worth explaining.

Cloudflare Web Analytics counts page views without cookies. It does not fingerprint your device, does not track you across other websites, and collects no personal data. There is nothing to opt into or out of, because nothing is stored on your device. It runs on every page except the Kids & Teens pages (see Children below) and the pages listed under Pages we leave out of both tools.

Google Analytics 4 is a Google product. It stores a cookie (_ga) on your device to tell a returning visitor from a new one, and it sends information about the pages you view — page address, referring page, approximate location from your IP address, and general device and browser type — to Google, who processes it on our behalf under their own privacy terms. Google discards the full IP address on collection and does not store it. We do not upload your email address or any other identifier to it, and no one on our side can use it to see what any individual person read.

Google Ad Grants and Google Ads. CancerExplained.org receives free search advertising through Google’s Ad Grants program for nonprofits, which requires reporting conversion activity to Google Ads each month to remain eligible. To meet that requirement, this site’s GA4 property is linked to a Google Ads account, and a small set of anonymous, aggregate product-usage signals — for example, that a reader finished reading an article, or used the symptom decoder, counted as an event with no identifying detail — flow through that link as conversions. What does not happen: no ad personalization, no remarketing or retargeting lists built from your visit, no audience-building, and nothing you typed (a search query, a chat message, a form field) is ever part of that signal. Every event name and value this site is allowed to send is fixed in advance to a short, closed list — a new kind of event cannot be added without a code change, so this description cannot silently go stale the way a settings toggle could.

Your choice. If you are in the EU, the EEA, the UK, or Switzerland, we ask before that Google Analytics cookie is set, and nothing is stored until you say yes. Elsewhere it is on by default. Either way you can change your mind at any time using the Cookie preferences link at the bottom of every page — declining takes effect immediately and nothing on the site stops working. If your browser sends a Do Not Track or Global Privacy Control signal, we treat it as a no: Google Analytics is not turned on and our own anonymous event counts are not sent, even if you said yes earlier.

Pages we leave out of both tools. Neither tool runs on the search page (the address of a search includes the words you typed), on a card someone sent you (the address carries the card’s message), or on the private pages for Reprint Memories requests and receipts (their addresses carry a private link code). Our code turns Google Analytics off on those pages, and they are sent with an instruction telling Cloudflare not to add its analytics scripts to them.

Neither tool receives anything you type into the site’s interactive tools, and neither receives health information. What you select in the Cancer Diagnosis Navigator, the symptom guide, and the other tools stays in your browser, as described below.

Interactive tools and your selections

Our educational tools are built to keep your choices on your own device. When you use the Cancer Diagnosis Navigator, the symptom guide, or the screening checklist, your selections stay in your browser only. They are not stored on our servers, not saved to your account (there is no account), and not sent anywhere. For the symptom guide and screening checklist, closing the tab clears them. The Navigator keeps your answers and roadmap in your browser’s local storage so My Journey can show them later; clear them with the Navigator’s start-over option or your browser settings.

A few tools, such as doctor visit prep and saved progress on My Journey, remember your work between visits using your browser’s local storage on your device. That information stays in your browser; you can clear it any time through your browser settings. We deliberately do not collect health-related selections from these tools.

Remembered on this device. On return visits, the homepage can show “Pick up where you left off” (the last “What brings you here today?” choice you tapped) and “Continue reading” (the last few articles you opened). Both are stored only in your browser’s local storage on this device, are never sent to us or anyone else, and use no cookies or analytics. Anyone using the same browser on this device can see them. To clear them, use the “Clear” buttons on the homepage, or clear this site’s data in your browser settings.

Game progress cookie. The “Where in the World?” game saves your level (as experience points), passport stamps, trip stamps, wish list, badges, daily-challenge streak and your display and sound choices, all as a few short numbers, in one small cookie named ce_where. It is set only after you press Start, and it holds nothing personal: no name, email or ID. It is used only to remember your place in the game. It is not sent to analytics, there is no account, and we do not use it to identify you. It works only on pages under /games, uses SameSite=Lax, and lasts about one year. To clear it, use the game’s “Reset my progress” button, or clear this site’s cookies in your browser settings. Because it only makes the game work the way you expect, the Cookie preferences choice does not turn it on or off.

Saved report terms. If you tap “Save term” in the report highlighter or on a report-terms page, the term’s name and the address of its page are kept in your browser’s local storage on this device as “My saved terms”. The report text you paste into the highlighter is never saved or sent anywhere. Saved terms are not sent to us and use no cookies or analytics; anyone using the same browser can see them. Use “Clear all” on the highlighter page, or clear this site’s data in your browser.

The Ask feature is the one exception where text you type is sent to our server so it can find relevant educational content and respond. The answer is made from passages on our own pages, so what you type there is not sent to an AI company or any other outside service. Please do not enter personal or medical details there. We ask you not to include information that could identify you.

Reprint Memories photo requests

If you ask us to recreate an item from an old photo through Reprint Memories, we store the photos you upload exactly as you sent them, in private storage with our hosting provider, Cloudflare, under random file names and with no public web address. Your email, any names, the words you remember and your story are kept in a separate private database. Only the people handling your request see them. We use your photos only for that request: never for marketing and never to train AI. We delete them 180 days after the request if no design is approved, or 90 days after the keepsake is sent, and sooner whenever you ask. The Reprint Memories rights and privacy policy has the details.

A note on health information

Please do not submit sensitive personal medical information unless a form specifically requests it. This site cannot give individualized medical advice, and general contact forms and chat features are not a secure place to share health details.

Links to other sites

We link to the National Cancer Institute and other trusted government, academic, and nonprofit resources. Those sites have their own privacy policies, which we don’t control.

Children

This site is intended for a general adult audience seeking educational information. Our Kids & Teens pages are written so young readers can understand them. On those pages we do not show the newsletter sign-up, our code turns Google Analytics, conversion tracking and our own event counts off, and the pages are sent with an instruction telling Cloudflare not to add its analytics scripts to them.

Accessing, updating, or deleting your information

You can ask us to access, correct, or delete the personal information we hold about you (such as your newsletter email). Email us at info@cancerexplained.org and we’ll help.

Changes

If this policy changes, we’ll update this page. Continued use of the site means you accept the current version.