How Often Will You Need — a PET-CT After Treatment?

For Hodgkin lymphoma and aggressive B-cell lymphomas like DLBCL, a PET-CT at end of treatment is standard and used to confirm remission. After that, NCCN and ESMO guidelines generally do not recommend routine surveillance PET-CT, because evidence has not shown it catches recurrences in a way that improves outcomes. Ongoing follow-up typically means clinical appointments and blood markers, with imaging ordered if symptoms or clinical findings arise rather than on a fixed schedule.

For many cancer types, yes. CT, MRI, and blood markers are the primary follow-up tools for most cancers, and PET-CT is reserved for specific clinical questions. This is consistent with NCCN and ASCO guidance for breast, colorectal, and most lung cancers. If you want to understand the reasoning, ask your team which markers or scans they are using and what would prompt them to order a PET-CT. That is a reasonable question to ask at any appointment.

A CT scan shows the size and shape of structures in your body. A PET-CT adds a radioactive tracer — usually a glucose-based compound — that concentrates in cells with high metabolic activity, which cancer cells often are. The PET component shows where that activity is occurring; the CT locates it precisely in the body. This makes PET-CT particularly useful for identifying active disease that may not yet show a size change on CT, or for distinguishing active tumour from scar tissue after treatment.

It is available privately in India. Before doing so, discuss it with your oncologist — a scan done outside your clinical plan can produce ambiguous findings that need clinical context to interpret correctly. In some situations a different investigation would answer your concern more directly. If you proceed, share the result with your treating team rather than interpreting it independently, because PET-CT findings always need to be read alongside your full clinical picture.

Costs vary by city and imaging centre, and prices change over time, so any figure here would quickly become outdated. The cost is significant enough that it is a reasonable factor in planning your follow-up. CION coordinates PET-CT through partner imaging centres; your care team can advise on current indicative pricing and whether any government scheme or insurance applies to your scan. If cost is a concern, raise it directly — the team can help you prioritise within your plan.

There is no fixed ceiling in guidelines. The cumulative radiation dose from multiple scans over several years is real, and it is one reason surveillance schedules typically move toward less frequent imaging as time in remission grows. If you have had many scans already and are concerned about cumulative dose, raise it with your oncologist so it can be factored into planning the next phase of your follow-up. It is a reasonable and increasingly common question to ask.