The short answer
Interval Growth is report language. In plain English, it means a finding is larger than it was on a prior scan. The phrase needs the rest of the report, your symptoms, prior scans, and your cancer history to know what happens next.
Interval Growth is a report description, not the whole diagnosis.
a finding is larger than it was on a prior scan
Growth can matter, but the amount, timing, and type of finding guide next steps.
The impression and recommended follow-up are usually the most practical parts of the report.
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The whole article, with every detail and caution.
This page is for people whose scan report mentions interval growth. It explains what the phrase means and what to ask.
What "interval" means on a scan report
The "interval" is the time between two scans. Interval growth means a finding is larger on your current scan than on an earlier one. A single scan cannot show it. Two scans have to be compared.
Why comparison matters
One scan is a snapshot. It shows a spot's size and shape. It does not show change over time. Radiologists look for earlier scans to compare. Your report often says whether earlier scans were available.
How doctors track change
In research and many treatment decisions, doctors use a set of rules called RECIST. NCI describes RECIST v1.1 as a way to judge response to treatment by changes in lesion size on imaging. Your team decides what counts as meaningful change for you. Ask what measurements they used.
What interval growth suggests, and what it does not
Growth in a known cancer may mean a change in plan is needed. Growth in a finding that looked low-risk before may lead your team to look at it more closely. Tests such as a biopsy are one option.
Interval growth alone does not prove cancer. Your team looks at the whole report, your symptoms, and your history. Ask them how much the finding changed and why.
What to ask your team
- How does this compare to my prior scan, and by how much did it change?
- Does this finding change my treatment plan?
- When is my next follow-up scan, and what would prompt an earlier one?
Sources
Common questions
Does "interval growth" mean cancer?
Not by itself. It means a finding is larger than it was on a prior scan. The rest of the report and your clinical context determine how concerning it is.
Why does this phrase appear on my report?
Interval Growth appears when a radiologist compares current and old imaging. It tells your care team what changed between scans.
What should I ask next?
Ask whether the finding is benign-appearing, indeterminate, or suspicious, whether old reports were compared, and what follow-up is recommended.
Questions to ask your doctor
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Your next step
Look up more plain-language explanations for report wording.
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Sources last checked: 2026-10-02 what this meansLast updated: 2026-10-02Next planned review: 2027-07-21
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Cancer Explained does not originate medical claims. Every page restates guidance already published by the National Cancer Institute, the CDC, the USPSTF and the FDA, in plain language, with the source cited so you can check the original yourself. AI does the translating and organizing; automated checks test claims, citations, clarity and safety before anything publishes, and this is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
Editorial status: Editorial review complete — This page completed Cancer Explained's editorial checks (sources, safety, plain language, duplication). It has not been reviewed by a physician or other healthcare professional.
Human medical review: not completed. Pages here are not signed off by a clinician before they publish. That is not an oversight we are quietly working around: we restate published guidance and cite it, so the authority belongs to the source rather than to us, and every page names where its claims come from — you can verify us instead of trusting us. Where a volunteer clinician has reviewed a page, their name and credentials appear on it; where no name appears, no clinician has checked it. We are glad to have reviewers and are recruiting them, and we do not hold pages back waiting for one. Use this site to understand your situation and to ask better questions of the people treating you.
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