More people are surviving cancer today than ever before. Better awareness, earlier detection, and improved treatments are all playing a part. But there’s another, often overlooked, contributor to this progress: medical imaging.

Specifically, a powerful scan known as PET-CT is quietly changing outcomes by giving doctors a clearer, more accurate view of what’s happening inside the body – not just at staging, but throughout treatment and recovery for cancers where it’s most appropriate.

Whether it’s catching cancer early, tracking how well treatment is working, or picking up subtle signs that cancer may have returned, PET-CT is helping doctors make better decisions, faster. For patients, that means more personalised care, fewer unnecessary interventions and, ultimately, a better chance of recovery. 

A clearer view from the start

One of the biggest challenges in treating cancer is knowing exactly where it is, how aggressive it might be, and how it’s behaving. Traditional scans, like X-rays, CTs, and MRIs, show the structure of the body and the size and shape of tumours or abnormalities. But they can’t always help doctors to determine whether those abnormalities are cancerous, or how ​​metabolically active the cancer really is.

That’s where F-18 FDG PET-CT (Positron Emission Tomography – Computed Tomography) makes a difference. It combines two types of scans into one. The CT scan shows a detailed map of the body’s anatomy, while the PET scan shows how cells are functioning, especially how much glucose they’re using. Many cancer cells use more glucose than normal cells, a sign of increased metabolic activity (or hypermetabolism), so they show up as brighter areas on the scan. Together, this dual approach gives doctors a clearer picture of both the structure and function of a tumour, helping them understand not just where the cancer is, but also how it’s behaving.

For many patients, this level of insight means that cancer is caught and staged correctly right from the beginning. With this accuracy, doctors can plan the most appropriate treatment, whether that means surgery, radiation, chemotherapy, or a combination of therapies.

Helping doctors pivot when things change

Cancer doesn’t always behave predictably. Some tumours respond quickly to treatment; others don’t. Doctors have always used a combination of clinical exams, blood tests, and imaging like CT, ultrasound, or MRI to monitor how a patient is responding. But these methods sometimes can’t show the full picture, especially when it comes to how the cancer is behaving at a metabolic level.

That’s where PET-CT adds another layer of insight. By highlighting changes in the cancer’s glucose use, PET-CT helps doctors understand whether treatment is working on a cellular level, even before the tumour changes size. With this information, doctors can make more confident decisions earlier in the treatment process, adapting the plan if needed to give each patient the needed care.

This kind of responsiveness may have a big impact on the outcome. For example, in lymphomas and some lung cancers, PET-CT is used partway through treatment to see if the cancer is responding. If not, the treatment plan can be changed early, increasing the chances of success and reducing unnecessary side effects from therapies that aren’t helping.

Tailoring treatment

More isn’t always better when it comes to cancer treatment. Every therapy, from radiation to chemotherapy to immunotherapy, carries its own risks and side effects. PET-CT helps ensure that patients receive the treatment they need, but not more than is necessary.

If a scan shows that a tumour is no longer metabolically active, doctors may choose to stop treatment early or reduce its intensity. On the other hand, PET-CT might reveal that the cancer has spread further than originally thought, guiding doctors towards a more appropriate treatment path.

In either case, PET-CT gives doctors the information they need to choose the right level of intervention, whether that means scaling back or taking a different approach altogether. For instance, if a patient’s scan shows that cancer hasn’t spread as initially suspected, a more aggressive surgery may be avoided in favour of a less invasive approach.

Catching recurrence early

Surviving cancer isn’t just about finishing treatment. It’s about staying cancer-free in the months and years that follow. Unfortunately, recurrence is a real concern for many patients.

PET-CT plays a vital role in follow-up care. It's often used to assess how well treatment has worked, typically a few months after a treatment cycle ends. At this point, doctors look for any signs of residual or recurrent disease, helping them confidently decide on the next steps.

In certain cancers, like melanoma, PET-CT may also be used to detect recurrence before symptoms appear. In these cases, early detection and treatment have been shown to improve outcomes. However, this approach doesn’t apply to all cancers. For others, like some types of lymphoma, PET-CT is only used if there are signs or symptoms that raise concern, such as a new lump or abnormal blood test.

The value of PET-CT lies in its ability to guide the right action at the right time based on what’s happening to cells in the body – evaluating not just what they look like, but also how they are functioning.

Supporting health beyond treatment

So, how does this all add up to better long-term health?

It’s simple: when cancer is staged accurately, treated effectively, monitored closely, and adjusted in real time, patients are more likely to get the right care when they need it most.

Research shows that PET-CT doesn’t just offer clearer images, it often leads to real changes in how doctors manage cancer. In one large study of patients with non-small cell lung cancer (NSCLC), PET-CT altered the treatment plan in over 40% of cases, helping doctors avoid surgery when it wasn’t appropriate and instead choose a more effective therapy path.

In prostate cancer, a study published in The Journal of Nuclear Medicine found that PET-CT changed the treatment approach in 41% of patients with suspected recurrence and in 91% of those cases, the change was considered major. Similarly, for patients with differentiated thyroid cancer, PET-CT influenced treatment decisions in two-thirds of cases.

These findings show that PET-CT is a decision-making ally. When doctors have a clearer understanding of how cancer is behaving, they can act quickly, tailor treatments more precisely, and give patients the needed care. 

Giving patients confidence

Beyond the clinical data and survival statistics, PET-CT offers something more personal: peace of mind. Knowing that your care team can track the cancer’s response to treatment or investigate signs of recurrence helps patients feel more informed, more in control, and more reassured about the decisions being made. While PET-CT isn’t routinely used for general surveillance in all cancers, it plays an important role in follow-up when there’s a clinical reason to look deeper.

It also supports better conversations between doctors and patients. When a PET-CT scan shows visible improvement, it’s a powerful confirmation that treatment is working. For patients, this can ease the uncertainty and anxiety that often come with cancer treatment. And if it reveals something unexpected, they can take comfort in knowing their team has the information needed to respond with a clear plan in place.

The role of PET-CT in your cancer journey

It’s important to note that PET-CT isn’t used for all cancers or all patients. Its role depends on your specific diagnosis, the type of cancer, and how your treatment plan is structured. But for many cancers – including lymphoma, lung, breast, head and neck, colorectal, gynaecological, prostate and melanoma – PET-CT is becoming integral to cancer care.

At Life Healthcare, we use PET-CT to support personalised, data-driven decisions that may improve outcomes.

If you or a loved one is navigating a cancer diagnosis, speak to your doctor about whether PET-CT would be appropriate for your care plan. For more information, visit Life Diagnostics.