Reading Your PSMA PET Report: — PRIMARY Score and miTNM Explained

A high PRIMARY score means the radiologist considers a finding highly likely to represent prostate cancer. It does not by itself tell you the cancer has spread — that depends on where the finding is located, whether it was already known from earlier scans, and how it fits with your PSA and clinical history. Your oncologist interprets the score in context. A score on its own is not a verdict, and a single finding is never the whole story.

PSMA PET and CT measure entirely different things. CT shows anatomy — the size and shape of structures. PSMA PET shows molecular activity — where PSMA is being expressed. Because they answer different questions, they use different reporting languages. Your PSMA PET report uses PRIMARY scores and miTNM staging; your CT report uses descriptive radiology language and conventional TNM. Your oncologist is trained to read both and to understand what each contributes.

A PRIMARY score of 1 or 2 means the radiologist considers a finding unlikely to represent prostate cancer — either because PSMA uptake was absent or because it was low and more likely to reflect normal tissue or a benign process. It does not necessarily mean the scan was normal overall. Other areas in the report may have received different scores. Your oncologist will explain the significance of each finding in context, not just the lowest or highest score on the page.

Yes. If you have PSMA PET scans at different points in your treatment, findings may receive different scores over time. A site previously scored high may show reduced uptake after treatment, which can indicate a response. A previously low-scoring or absent site may show new uptake, which may indicate new disease. Comparing scans over time is one way your oncologist assesses whether treatment is working. Having scans at the same centre, with the same tracer, makes that comparison more reliable.

A nuclear medicine physician or a radiologist with specialist training in molecular imaging reads and writes the report. At CION, PSMA PET-CT is coordinated through partner imaging centres at an indicative cost of around ₹23,999; availability and tracer supply are confirmed at the time of booking, because PSMA tracers have a short shelf life and must be ordered in advance. The report returns to your oncologist before your next appointment. As with all imaging, the scan is a diagnostic tool — it provides the clearest currently available picture of PSMA-expressing disease, but no scan guarantees detection of every lesion.

Ask four things: what PRIMARY score or scores were assigned and what they mean for your situation specifically; what the miTNM staging shows and how it compares with any earlier staging; whether any finding was uncertain and needs follow-up imaging or biopsy; and what this report changes about your treatment plan, if anything. Write the answers down or bring a family member to take notes. It is entirely reasonable to ask for the plain-language version before the medical version.