PET Scan Exam: A Step-by-Step Walkthrough for Patients

A PET scan exam can feel intimidating before the day. Patients often arrive without a clear picture of how long it will take, whether it will hurt, or what they can or cannot do beforehand. This guide walks through the entire experience from preparation to results so patients arrive informed and leave without surprises.

What a PET Scan Exam Means

A PET, or positron emission tomography, exam is a nuclear medicine imaging test. Unlike a CT scan that shows anatomy or an MRI that shows soft tissue detail, PET shows function. A small amount of a sugar-like radioactive tracer is injected into the bloodstream, where it concentrates in tissues that consume glucose at high rates. Cancer cells, active inflammation, and working heart muscle are the most common targets.

In practice, almost all modern PET scans are performed as PET-CT, meaning a low dose CT is taken in the same session. The CT provides the anatomical map, and the PET overlay shows where in that map there is unusual metabolic activity. Some centers offer PET-MRI, which combines PET with magnetic resonance imaging for higher soft tissue detail at higher cost.

How the Scan Is Performed

The exam begins with preparation a day or two before. Patients are told to avoid strenuous exercise for 24 hours, to follow a low carbohydrate diet for one day, and to fast completely for at least six hours before the scan. Water is allowed and encouraged.

On arrival at the imaging center, the technologist will:

• Confirm the patient's identity, indication, and recent medical history
• Measure blood glucose with a finger stick
• Place an intravenous line in the arm
• Inject the radiotracer
• Settle the patient in a quiet, dimly lit room to rest for about 60 minutes

After the uptake period, the patient is asked to empty the bladder and lie on the scanner table. The scan itself takes 20 to 40 minutes depending on the protocol and scanner generation. Patients lie still on their back with arms raised above the head for most protocols. The scanner is open at both ends, shorter than an MRI machine, and rarely causes claustrophobia.

Total time at the center is typically three to four hours from check in to discharge.

Clinical Indications

A PET scan exam is ordered for specific reasons rather than as a general screening test. Common indications include:

• Initial staging of newly diagnosed cancer
• Assessing how well chemotherapy or radiation is working
• Detecting cancer recurrence when tumor markers rise
• Locating the source of cancer when the primary site is unknown
• Cardiac viability before bypass surgery
• Epilepsy surgery planning
• Fever of unknown origin
• Suspected large vessel vasculitis

PET is not used as a general health screen for asymptomatic adults at most reputable centers, because the radiation dose and false positive rate do not justify routine use.

Cost in US, UK, China

A standard PET-CT exam on a self-pay basis costs:

• United States cash price: $3,500 to $6,500
• United Kingdom private: GBP 1,500 to 2,500
• Mainland China top hospitals: RMB 6,500 to 9,000, roughly $930 to $1,290
• Hong Kong private: HKD 12,000 to 18,000
• Singapore: SGD 2,500 to 4,500
• Thailand: THB 30,000 to 60,000

The Chinese price is consistently the lowest among countries that operate digital PET-CT systems. Top centers including Peking Union Medical College Hospital, Fudan University Shanghai Cancer Center, and Sun Yat-sen University Cancer Center use the same Siemens and GE scanners as major US and European hospitals.

Quality Markers for PET Centers

When choosing where to have a PET scan exam, patients should look for:

• A digital PET-CT scanner with silicon photomultiplier detectors
• An onsite radiopharmacy producing fresh FDG daily
• Nuclear medicine physicians with subspecialty training
• Subspecialty reading, meaning the oncology PET is read by a physician who reads oncology PET routinely
• Comparison with prior scans, ideally on the same scanner platform
• English-language reports for international patients

Top tier centers in China meet all of these criteria.

Choosing the Right Hospital

The right choice depends on the indication. For oncology staging, a dedicated cancer center has the highest case volume. For cardiac PET, a center where nuclear medicine and cardiology work together is best. For neurological PET, an academic medical center with neurology subspecialty support is preferred.

Geography matters for self-pay international patients. Major Chinese cities including Beijing, Shanghai, Guangzhou, Shenzhen, and Chengdu all host top centers with English-speaking patient coordinators. A coordinator can pre-book the scan, gather prior imaging for comparison, and translate the report into English, which makes the entire process faster and clearer.

Frequently Asked Questions

Does a PET scan hurt?
No. The only physical sensation is the needle stick for the intravenous line. The injection of tracer is painless. Lying still during the scan can become uncomfortable for patients with back pain, in which case the technologist can provide pillow support.

Can I eat or drink before the exam?
Water and prescription medications are allowed. Solid food, sweetened beverages, gum, and mints should be avoided for at least six hours before the scan to keep blood glucose low.

How long does the radioactivity stay in my body?
The FDG tracer has a half life of about 110 minutes. Most of it has decayed and been excreted by the end of the same day. Patients are advised to drink plenty of water and avoid prolonged close contact with pregnant women and infants for the remainder of the day.

When do I get the results?
At top Chinese hospitals, a written radiology report is typically available within one to two business days. SinoCareLink can arrange same day verbal preliminary findings when the situation is clinically urgent.

Need Help Booking?

SinoCareLink can pre-book your PET scan exam at a top Chinese cancer center, translate reports into English, and arrange airport pickup. Contact us for a free consultation.