Understand your cancer report
A report can be full of unfamiliar words. These plain-language explanations tell you what a phrase means, what it does not prove, and what to ask — so the conversation with your care team makes more sense.
These pages explain report language in general. They cannot interpret your personal report — only your care team can do that.
Most-searched report language
Direct links to high-intent report terms
These terms show up in pathology, imaging, lab, biomarker, and oncology notes. They now get stronger hub links so patients and search crawlers can reach them faster.
- ECOG performance statusHow activity level may be recorded in oncology notes and trial criteria.
- Karnofsky performance statusAnother common score for function, symptoms, and treatment planning.
- TNM stagingTumor, Node, and Metastasis language used to describe spread.
- BI-RADS 4What this mammogram category can mean and what usually happens next.
- Oncotype DX scoreHow recurrence-score language can come up in breast cancer decisions.
- MammaPrint scoreWhat a genomic-risk result can and cannot tell by itself.
- M-protein spikeA lab term people often see in myeloma and related blood-work conversations.
- PSA densityHow PSA is sometimes interpreted with prostate size and other risk details.
- EGFR exon 20A lung-cancer biomarker phrase that can affect treatment questions.
Watch: report explainers
Short captioned videos that walk through each kind of report in plain language.
How to read a cancer pathology report3 min · Captioned
Biopsy results, explained3 min · Captioned
Cancer staging and TNM, explained3 min · Captioned
Grade vs. stage — what's the difference?2 min · Captioned
Surgical margins, explained2 min · Captioned
Tumor markers, explained3 min · Captioned
How to read a CT or MRI report3 min · Captioned
Pathology report language
The words a pathologist uses to describe tissue removed by biopsy or surgery.
- What Does "Positive Margin" Mean in a Pathology Report?A positive margin means cancer cells were found at the edge of removed tissue. What that does and doesn't mean, and what to ask your care team.
- What Do "Negative" and "Close" Margins Mean?A negative (clear) margin means no cancer cells were seen at the edge of removed tissue. A close margin is nearby. What each means and what to ask.
- What 'Poorly Differentiated' Means on Your Report"Poorly differentiated" describes how abnormal cancer cells look under the microscope. What differentiation and grade mean, and what to ask your team.
- What Does "Lymphovascular Invasion" Mean?Lymphovascular invasion (LVI) means cancer cells were seen inside small blood or lymph vessels in the tissue sample. What it suggests and what to ask.
- What Does "Positive Lymph Node" Mean?Positive Lymph Node explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does "High Grade" Mean?High Grade explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does "Low Grade" Mean?Low Grade explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does Pathologic Complete Response Mean?pathologic complete response: what it usually means, what it does not prove, and what to ask next.
- What Does "Suspicious For Malignancy" Mean?Suspicious For Malignancy explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does "Cannot Exclude Malignancy" Mean?Cannot Exclude Malignancy explained in plain English: what it can mean, what it cannot prove, and what to ask next.
Biomarkers
Features tested on the cancer that can guide treatment choices.
- What Does HER2 Positive, Negative, or Low Mean?HER2 is a protein tested on some cancers, especially breast cancer. What HER2 positive, negative, and low mean, and how they guide treatment options.
- What Does "Triple-Negative" Breast Cancer Mean?Triple-negative means a breast cancer tests negative for estrogen receptors, progesterone receptors, and HER2. What that means for treatment options.
- What Does an EGFR Mutation Mean?An EGFR mutation on a lung cancer report points to a specific set of pills. Which exon it sits in decides which ones, and it also explains why immunotherapy is usually held back.
- What Does an ALK Rearrangement Mean?ALK rearrangement explained for patients: what it is, why it may affect treatment options, and what to ask about testing.
- What Does a KRAS G12C Mutation Mean?KRAS G12C explained for patients: what it is, why it may affect treatment options, and what to ask about testing.
- What Does a BRAF V600E Mutation Mean?BRAF V600E explained for patients: what it is, why it may affect treatment options, and what to ask about testing.
- What Does PD-L1 TPS Mean?PD-L1 TPS explained for patients: what it is, why it may affect treatment options, and what to ask about testing.
- What Does PD-L1 CPS Mean?PD-L1 CPS explained for patients: what it is, why it may affect treatment options, and what to ask about testing.
- What Does MSI-H Mean on a Report?MSI-H on a pathology report means the tumor lost its DNA proofreading. What that opens up in treatment, what it says about Lynch syndrome, and what it cannot tell you.
- What Does dMMR Mean on a Cancer Report?dMMR means deficient mismatch repair. What the four proteins are, how it relates to MSI-H, the two drugs approved on this marker alone, and the response rates behind those approvals.
- What Does TMB-High Mean on a Report?TMB-high explained for patients: what it is, why it may affect treatment options, and what to ask about testing.
- What Does an NTRK Fusion Mean?NTRK fusion explained for patients: what it is, why it may affect treatment options, and what to ask about testing.
- What Does HER2-Low Mean on a Report?HER2-low explained for patients: what it is, why it may affect treatment options, and what to ask about testing.
- What Does HRD-Positive Mean?HRD-positive explained for patients: what it is, why it may affect treatment options, and what to ask about testing.
- What Does a BRCA Tumor Mutation Mean?BRCA tumor mutation explained for patients: what it is, why it may affect treatment options, and what to ask about testing.
- EGFR Mutation in Lung CancerEGFR mutation in non-small cell lung cancer: why it matters, report wording, and questions to ask.
- ALK-Positive Lung Cancer: MeaningALK rearrangement or ALK fusion in non-small cell lung cancer: why it matters, report wording, and questions to ask.
- KRAS G12C in Lung Cancer: MeaningKRAS G12C in lung cancer: why it matters, report wording, and questions to ask.
- KRAS G12C in Colorectal CancerKRAS G12C in colorectal cancer: why it matters, report wording, and questions to ask.
- MSI-H Colorectal Cancer: MeaningMSI-H or dMMR in colorectal cancer: why it matters, report wording, and questions to ask.
- dMMR Endometrial Cancer: MeaningdMMR in endometrial cancer: why it matters, report wording, and questions to ask.
- BRCA Mutation in Ovarian CancerBRCA mutation in ovarian cancer: why it matters, report wording, and questions to ask.
- BRCA Mutation in Prostate CancerBRCA mutation in prostate cancer: why it matters, report wording, and questions to ask.
- HER2-Low Breast Cancer: MeaningHER2-low in breast cancer: why it matters, report wording, and questions to ask.
- HRD-Positive Ovarian CancerHRD-positive in ovarian cancer: why it matters, report wording, and questions to ask.
- What Does Circulating Tumor DNA Mean?circulating tumor DNA: what it usually means, what it does not prove, and what to ask next.
- What Does Tumor-Informed ctDNA Mean?tumor-informed ctDNA: what it usually means, what it does not prove, and what to ask next.
- What Does Minimal Residual Disease Mean?minimal residual disease: what it usually means, what it does not prove, and what to ask next.
- What Does Molecular Residual Disease Mean?molecular residual disease: what it usually means, what it does not prove, and what to ask next.
- What Does Signatera Mean?Signatera: what it usually means, what it does not prove, and what to ask next.
- What Does Guardant360 Mean?Guardant360: what it usually means, what it does not prove, and what to ask next.
- What Does PARP Inhibitor Mean?PARP inhibitor: what it usually means, what it does not prove, and what to ask next.
- What Does CAR T-Cell Therapy Mean?CAR T-cell therapy: what it usually means, what it does not prove, and what to ask next.
- What Does Antibody-Drug Conjugate Mean?antibody-drug conjugate: what it usually means, what it does not prove, and what to ask next.
Scan & imaging report language
Phrases radiologists use to describe what they see — and how sure they are.
- What Does "Ground-Glass Opacity" Mean on a Lung Scan?A ground-glass opacity (GGO) is a hazy area on a lung CT scan. It has many causes — most not cancer. What GGO means and what follow-up may involve.
- What Does a "Pulmonary Nodule" Mean on a Scan?A pulmonary nodule is a small spot in the lung found on imaging. Most are not cancer. What a nodule means and how doctors decide on follow-up.
- What Does BI-RADS Mean on a Mammogram Report?BI-RADS is a standard 0-to-6 scale radiologists use to summarize a mammogram result. Here's what each category means and what to ask.
- What Does BI-RADS 3 Mean?BI-RADS 3: what it usually means, what it does not prove, and what to ask next.
- What Does BI-RADS 4 Mean?BI-RADS 4: what it usually means, what it does not prove, and what to ask next.
- What Does BI-RADS 5 Mean?BI-RADS 5: what it usually means, what it does not prove, and what to ask next.
- What Does PI-RADS Mean on Prostate MRI?PI-RADS: what it usually means, what it does not prove, and what to ask next.
- What Does LI-RADS Mean on a Liver Scan?LI-RADS: what it usually means, what it does not prove, and what to ask next.
- What Does Thyroid Nodule TI-RADS Mean?thyroid nodule TI-RADS: what it usually means, what it does not prove, and what to ask next.
- What Does O-RADS Mean on a Pelvic Report?O-RADS: what it usually means, what it does not prove, and what to ask next.
- What Does "Incidental Finding" Mean on a Scan?An incidental finding is something spotted on a scan that wasn't what the test was looking for. Most are harmless. What it means and what follow-up may involve.
- What Does "Suspicious" or "Indeterminate" Mean on a Scan?"Suspicious" and "indeterminate" describe how confident a radiologist is about a finding — not a diagnosis. What each means and what usually happens next.
- What Does 'Enhancing Lesion' Mean on MRI?An enhancing lesion is an area that becomes more visible after contrast. It is a clue, not a diagnosis.
- What Does 'Contrast Enhancement' Mean on a Scan?Contrast enhancement means a tissue or spot becomes easier to see after contrast. It is a scan feature, not a diagnosis.
- What Does 'Reactive Lymph Node' Mean?A reactive lymph node usually means the node looks active from immune response, often infection or inflammation, not automatically cancer.
- What Does 'Subcentimeter Lymph Node' Mean?Subcentimeter means smaller than one centimeter. A small lymph node can be normal, reactive, or occasionally still important depending on context.
- What Does 'Bone Lesion' Mean on a Scan?A bone lesion is an abnormal area in bone. It can be benign, injury-related, infection-related, or cancer-related depending on the pattern.
- What Does 'Lytic Lesion' Mean on a Scan?A lytic lesion is an area where bone looks broken down or less dense. It can have benign, infection-related, or cancer-related causes.
- What Does "Hypodense Lesion" Mean?Hypodense Lesion explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does "Hypoattenuating Lesion" Mean?Hypoattenuating Lesion explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does "Sclerotic Lesion" Mean?Sclerotic Lesion explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does "Solid Mass" Mean?Solid Mass explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does "Cystic Mass" Mean?Cystic Mass explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does "Interval Growth" Mean?Interval Growth explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does "Stable Nodule" Mean?Stable Nodule explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does "SUV Max" Mean?SUV Max explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does "Mild Uptake" Mean?Mild Uptake explained in plain English: what it can mean, what it cannot prove, and what to ask next.
- What Does "Borderline Enlarged Lymph Node" Mean?Borderline Enlarged Lymph Node explained in plain English: what it can mean, what it cannot prove, and what to ask next.
Stage, grade & response
How far the cancer has spread, how the cells look, and how treatment is working.
- Stage vs. Grade: What's the Difference?Stage describes how far a cancer has spread. Grade describes how abnormal the cells look. They answer different questions — here's how they fit together.
- What Does "No Evidence of Disease" (NED) Mean?"No evidence of disease" (NED) means tests can't detect cancer right now. How NED differs from "cured," and what it means for follow-up.
- Remission vs. No Evidence of Disease: What's the Difference?"Remission" and "no evidence of disease" overlap but aren't identical. What complete and partial remission mean, and how NED fits in.
- What Does 'Bone Metastasis' Mean?Bone metastasis means cancer has spread to bone from another part of the body. It is different from primary bone cancer.
Next step
Turn what you read into questions for the team who can interpret your report.
Looking for a single word? Try the glossary or site search. Getting ready for a visit? See Prepare for your appointment.
How this page was created
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. We do not employ clinicians and do not intend to — our work is translation and navigation, not clinical judgment. Nothing here is personal medical advice, and no page can account for your particular situation.
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