How Many Cycles Before — Your First Scan?

Usually not on the same day. Your oncologist often reviews the images alongside colleagues at a multidisciplinary meeting before explaining the result to you — that typically happens within a few days of the scan. Ask your team before your scan date how the result will reach you, whether by phone, a separate appointment, or at your next scheduled visit, so you are not waiting without knowing what to expect.

Not necessarily, and this is one of the fears most worth naming early. Feeling worse in the first weeks can reflect the treatment doing its job — inflammation, immune activation, or the body adjusting — rather than the disease progressing. It can also reflect side effects that are unrelated to how the tumour is responding. What it is not is something to wait out quietly until the scan. Call your team the same day and describe exactly what has changed. They may reassure you, adjust your supportive care, or bring the assessment forward.

You can ask, and your team will explain their reasoning. In most cases the timing reflects what the scan can realistically show, and an earlier scan is unlikely to give meaningful information even when it is technically possible to arrange. If your symptoms have clearly worsened, your team may decide to reassess sooner — but that decision is based on your clinical picture, not the scan date alone. Raising your concerns is always the right step; the timing can be reconsidered if there is a clinical reason to do so.

For most solid tumours, the scan compares the size and extent of the tumour or tumours against measurements taken before treatment began. A reduction in size suggests a response; no change may indicate stable disease; an increase raises a question about whether to continue. For some cancers, other markers — such as metabolic activity on a PET scan — are used alongside or instead of size alone. Your oncologist will explain which measures apply to your cancer type and what the result means for your specific situation.

A partial response — where the tumour has reduced but not disappeared — is a meaningful and often expected result at first assessment. It generally means treatment is having an effect and may continue on the same plan. Your oncologist will explain what the degree of response means for your particular cancer, whether further cycles are planned before a second assessment, and what the result means for the overall treatment goal. A partial response is not a failure — it is information that guides the next decision.