A PET-CT request can sound worrying, especially when you have already had several scans. Before booking, ask what decision this scan is meant to help with. Understanding its purpose and getting the centre’s own preparation instructions can prevent avoidable travel, repeat testing and confusion.
What PET and CT show together
PET uses a radioactive tracer to show activity in tissues. CT uses X-rays to show their structure and location. A commonly used tracer, FDG, behaves similarly to glucose, but other tracers are used for particular questions. Your prescription should identify the intended examination. RadiologyInfo explains how PET-CT works.
Depending on the cancer and situation, PET-CT may help assess spread, treatment response or suspected recurrence. It is not automatically needed for every cancer or every follow-up. Ask your oncologist how the answer could change your care, rather than choosing a scan because it sounds more comprehensive. Common clinical uses of PET-CT.
A bright area is not a diagnosis by itself
Tracer uptake can occur in inflammation as well as cancer. A highlighted area therefore needs interpretation alongside your history and other findings. Avoid deciding from a coloured image or one number that cancer has definitely spread. PET-CT information from the radiology professional societies.
A scan also does not automatically remove the need for a biopsy. Tissue examination is often needed to establish a cancer diagnosis. Ask which findings are confirmed and which require another test. NCI guidance on diagnosing cancer. Our biopsy-report guide can help you organise those questions.
Ask these questions before paying or travelling
- What specific question should this scan answer, and how soon is it needed?
- Why is this examination preferred to other imaging in my situation?
- Can the team use my existing images, or is another scan necessary?
- Does the request specify a particular tracer or CT contrast?
- Who will review the result with me, and when?
Ask the centre for the total written estimate and what it includes. Confirm any insurance or scheme approval directly rather than assuming coverage. If travelling between cities, check the reporting time and whether you need to stay for a consultation. Keep your referring doctor’s contact details handy if the scan centre needs clarification.
Get an individual preparation plan
Preparation varies with the examination and your health. The scanning centre should tell you about eating, drinking, activity and medicines. Do not start fasting or change insulin, diabetes tablets or other medicines based on a general article. If you have diabetes or cannot safely miss meals, contact the centre before scan day. NHS PET-scan preparation guidance.
Tell the team about recent infection, surgery, chemotherapy or radiotherapy, and provide the dates. Also mention steroid treatment and any difficulty with injections or lying flat. These details can affect planning; let the team decide whether timing or preparation needs changing. Cambridge University Hospitals PET information.
Flag pregnancy or possible pregnancy, breastfeeding, allergies, and anxiety about enclosed spaces. Ask whether CT contrast is planned and whether additional checks are required. PET-CT involves radiation, so discuss the expected benefit and relevant precautions rather than assuming it is risk-free. PET-CT preparation and safety.
Plan for the whole appointment
The visit includes preparation, tracer injection, a waiting period and scanning. During imaging you need to remain still; staff can communicate with you. Ask the centre how much time to allow rather than planning around the scanning time alone. What happens during a PET scan.
- Carry the referral, appointment confirmation, previous scan images and reports, and treatment dates.
- Keep a current medicine and allergy list available.
- Confirm whether a companion can enter and where they can wait.
- Ask about language assistance, wheelchair access and support if positioning is painful.
- If you accidentally break a preparation instruction, tell staff before the injection. Do not hide it or try to compensate yourself.
Before you leave the centre
Get written instructions about eating, fluids, breastfeeding and any temporary contact precautions around pregnant people or young children. The duration depends on the examination, so use the centre’s instructions. Confirm how to obtain both the report and image files. After a PET scan.
If the report arrives before your appointment, write down questions rather than arranging repeat scans yourself. Our second-opinion preparation guide may help if your treating doctor recommends another review.
When not to wait
A scheduled scan is not emergency care. Seek emergency medical help for severe breathing difficulty, new confusion or rapidly worsening illness. Tell scan staff immediately if you feel unwell during the procedure. NHS urgent warning signs.
For non-emergency help preparing your next steps, contact Love Heals Cancer: call +91 99307 09000 or WhatsApp +91 98803 78899. These are not emergency services. This guide is general information; your treating and scanning teams’ instructions take priority.
Sources
- ACR and RSNA: PET/CT
- NHS: PET scan
- Cambridge University Hospitals: PET Department
- NCI: How Cancer Is Diagnosed
- NHS: Sepsis
Sources checked 24 October 2026. This is not an independent medical review.
Request a Cancer Counselor Callback
For patients and families across Uttar Pradesh and Bihar: for questions about reports, treatment options, costs or the Ayushman card, leave your name and phone number to request a callback from a patient counselor. काउंसलर से कॉलबैक का अनुरोध करने के लिए अपना नाम और फ़ोन नंबर छोड़ें।
Love Heals Cancer is a non-profit. We do not promise cures; treatment is decided by your oncologist. By submitting you agree to be contacted by phone/WhatsApp.
