PSMA PET Scan for Prostate Cancer: A Patient Guide

Quick answer: a PSMA PET scan uses a radioactive tracer that attaches to PSMA, a protein found in large amounts on most prostate cancer cells, to show where prostate cancer is in the body, often more accurately than CT and bone scans. It is used to stage higher-risk prostate cancer, to find the cancer when PSA rises after treatment, and to check whether you may be a candidate for PSMA-targeted therapy. Unlike a standard PET scan, you do not need to fast; just drink plenty of water. After the injection you rest for about 45 to 60 minutes, then the scan takes about 20 to 30 minutes.

PSMA PET has changed how prostate cancer is imaged. The men I scan are often in a stressful moment, waiting to know whether their cancer has spread or come back. The scan itself is one of the easiest PET scans to prepare for.

What is PSMA?

PSMA (prostate-specific membrane antigen) is a protein on the surface of prostate cells. Most prostate cancer cells have much more of it than normal cells. The tracer is designed to stick to PSMA, so areas of prostate cancer light up on the scan, including small spread to lymph nodes or bones that other tests can miss.

The PET part shows where the tracer has collected; the CT part, done in the same session, shows the anatomy so findings can be located precisely.

When is a PSMA PET scan used?

PSMA PET is used in men who already have a diagnosis of prostate cancer, typically:

At diagnosis, for men whose cancer may have spread, to stage it before treatment
When PSA rises after treatment (biochemical recurrence), after surgery or radiation, to find where the cancer has come back
Before PSMA-targeted therapy, such as lutetium-177 PSMA treatment, to check whether the cancer has enough PSMA to respond

It is not a screening test and is not used without a prostate cancer diagnosis.

FDA-approved PSMA tracers

Several PSMA PET tracers are approved by the FDA. Your center will use one of them:

Tracer	Brand names	Radioactive label	FDA approval
Gallium Ga 68 gozetotide (PSMA-11)	Illuccix, Locametz, Gozellix	Gallium-68	2021, 2022 and 2025
Piflufolastat F 18	Pylarify	Fluorine-18	2021
Flotufolastat F 18	Posluma	Fluorine-18	2023

For you as a patient, the experience is very similar whichever tracer is used.

How to prepare

No fasting: eat normally.
Drink plenty of water the day before and the morning of the scan.
Take your usual medications, including prostate cancer treatments, unless your team says otherwise. Bring a list of everything you take.
Avoid strenuous exercise the day before, as some centers advise.
Wear comfortable clothes without metal.
Arrive on time. The tracer is ordered and prepared specifically for you, so if you need to cancel, call as early as possible.
Bring previous scans (PET, CT, MRI or bone scans) done elsewhere, for comparison.

If your scan includes a CT with IV contrast, you may get specific instructions for that part. See [link: How to Prepare for a CT Scan With Contrast].

What happens on the day

Check-in and IV. Staff review your history and place a small IV in your arm.
Tracer injection. The tracer is injected through the IV. Most people feel nothing.
Uptake time. You rest for about 45 to 60 minutes while the tracer spreads through your body. You will usually be encouraged to drink water and empty your bladder.
Empty your bladder right before the scan, because tracer in the urine can hide the area around the prostate.
The scan. You lie on your back on the PET-CT table for about 20 to 30 minutes, usually from the skull base to mid-thigh. Stay as still as you can and breathe normally.

The whole visit often takes 2 to 3 hours.

From the scanner room: [TU EXPERIENCIA: diferencias prácticas entre el PET PSMA y el PET con FDG en tu servicio (preparación, hidratación, tiempos) y qué te preguntan los pacientes de próstata.]

After the scan

You can usually return to normal activities right away. Keep drinking water and empty your bladder often to help clear the tracer. As with other PET scans, your center may suggest avoiding prolonged close contact with babies, young children and pregnant women for a few hours. See [link: Am I Radioactive After a PET Scan? Precautions for Family and Pets].

Understanding your results

A radiologist or nuclear medicine physician interprets the scan, and results usually reach your doctor within a few days; one U.S. health system reports within 24 to 48 hours. In general terms:

Areas of PSMA uptake outside the normal pattern may represent prostate cancer in the prostate, lymph nodes, bones or other organs.
Normal uptake is expected in some organs, such as the salivary and tear glands, kidneys, bladder and parts of the bowel.
Not every spot is cancer. Some benign conditions, such as certain bone or nerve findings, can take up PSMA, and a small number of prostate cancers have little PSMA and may not show up.
A negative scan with a rising PSA is reassuring, but does not always rule out a small recurrence.

Your doctor will combine the results with your PSA, other tests and your treatment history.

Is it covered by insurance?

Medicare and many private insurers cover PSMA PET when it is used for an FDA-approved indication in a man with prostate cancer. Ask your doctor’s office to confirm prior authorization before the scan, as coverage rules vary. See [link: Does Medicare Cover MRI and PET Scans?].

Tips from the technologist

[TU EXPERIENCIA: 2-3 consejos propios. Ideas: beber agua desde el día antes, avisar si hay problemas para orinar o sonda, llevar los PSA recientes y estudios previos.]

Frequently asked questions

Do I need to fast before a PSMA PET scan?

No. Unlike the more common FDG PET scan, PSMA PET does not require fasting.

Is a PSMA PET scan better than a bone scan and CT?

For detecting prostate cancer spread, PSMA PET has been shown to be more accurate than conventional CT and bone scans in many situations. Your doctor decides which test is right for you.

How long does a PSMA PET scan take?

About 45 to 60 minutes of rest after the injection, then 20 to 30 minutes on the scanner. Plan for 2 to 3 hours in total.

Will hormone therapy affect my PSMA PET scan?

It can, because some hormone treatments change PSMA levels. Tell your team about all prostate cancer treatments, including timing.

Is the PSMA PET scan safe?

Yes. It uses a small amount of radioactive tracer, side effects are rare, and the radioactivity fades within hours. See [link: PET Scan: What to Expect From Start to Finish].

This article is for general information and does not replace advice from your doctor or care team.