How does my doctor use a CT scan to detect cancer?

November 6, 2023 – 19 min read

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You might start to worry when your doctor recommends a CT scan to see if you might have cancer. But don’t worry just yet. There’s still a lot for your medical team to learn.

We understand that the thought of cancer can be completely overwhelming, and we’re here to help. There are so many questions to ask, so many new things to understand, and so many decisions to make. 

Remember, this is just the beginning, and we don’t know anything until your healthcare team takes a closer look at your CT scan––plus other diagnostic tests, as well.

We want to make sure that you get the best possible CT results so you and your doctor can make informed decisions about your health. Here’s everything you’ll need to know.

What is a CT scan and how does it work?

A CT scan, or Computed Tomography scan, is a type of medical imaging procedure that uses a combination of X-rays and computer processing to produce detailed images of the inside of your body

Think of it like an advanced form of an X-ray that gives us a 3D view instead of just a 2D view.

Here’s how it works: a ring-shaped machine, the CT scanner, takes several X-ray images from various angles. The computer then combines these images to create a detailed, cross-sectional view of your body. 

This allows doctors to examine each layer of your body, almost like peeling an onion, but without making a single incision.

How does a CT scan help in detecting cancer?

When it comes to diagnosing cancer, precision is key. CT scans provide an invaluable tool in the quest for accurate diagnosis. 

They can show a tumor’s shape, size, location, and mass. Those are all critical details that help doctors determine if a growth is potentially cancerous.

Besides identifying the presence of tumors, CT scans also assist in determining cancer’s extent or severity, and whether it has spread to other parts of the body. This information is crucial for deciding the most effective course of treatment.

What types of cancer can be detected using a CT scan?

CT scans are incredibly versatile and can be used to detect a variety of cancers. This includes lung cancer, where the scans can reveal small nodules or tumors that may be missed by a standard X-ray. 

CT scans can also detect liver cancer, pancreatic cancer, and kidney cancer by highlighting abnormal growths in those organs. CT scans are also used in identifying brain tumors, as well as cancers of the colon and the ovaries. 

Even in cases where cancer originates from an unknown location, CT scans can help doctors identify the primary site. 

What are the advantages of using a CT scan for cancer diagnosis?

One of the major advantages of using CT scans for cancer diagnosis is their ability to provide a detailed and comprehensive view of the body. They can reveal small tumors and precise locations that other methods may miss. 

This level of detail can be critical in catching cancer early, when it is more likely to respond well to treatment.

CT scans also offer a non-invasive alternative to procedures like biopsies, which require a sample of the suspected tissue. For many people, the thought of a needle or surgery can be daunting. 

With CT scans, doctors can gather a wealth of information about the potential cancer without having to make a single cut.

CT scans can look at a person’s entire body to help determine whether cancer has spread beyond its original site. This has a significant impact on the management and treatment plan, facilitating a more personalized and effective approach.

Using CT scans to Diagnose Possible Cancer

If your doctor has suggested a CT scan for cancer detection, you might be anxious, or even a little worried. That’s absolutely normal. 

Most people feel that way, and with more information, we hope you’ll rest easier. For starters, you probably have questions about why a CT scan is necessary and how it works. 

When does a doctor recommend a CT scan for cancer diagnosis?

A doctor typically recommends a CT scan when there’s a need for a more comprehensive view of the body. 

If you’ve been experiencing persistent symptoms that can’t be explained, or if there’s a finding from a physical exam or another test that raises suspicion for cancer, a CT scan may be ordered. 

For instance, if you’ve been having chronic cough and chest discomfort, your doctor might recommend a CT scan to examine your lungs more closely. 

Sometimes, it’s also suggested as a follow-up test if something unusual or abnormal is detected in other screening tests like X-rays or ultrasounds

What are the specific indications for using a CT scan in cancer detection?

CT scans are particularly useful when the doctor suspects certain types of cancers. If there’s any potential for cancer in an organ (like someone’s lungs, liver, or kidneys), a CT scan can provide detailed imagery of these organs. 

CT scans are also valuable in cases where the doctor is trying to determine how far possible cancer has spread. 

A CT can detect swollen lymph nodes, a common sign that cancer has started to spread, and in some cases they can also help locate where the cancer originated, particularly when it’s found in more than one place.

Are there any alternative imaging techniques for cancer diagnosis?

While CT scans are a powerful tool in the diagnostic toolbox, they aren’t the only option. Depending on the type and location of the suspected cancer, your doctor might consider other imaging techniques. 

Magnetic Resonance Imaging (MRI), for instance, is often used when examining soft tissue cancers, like brain tumors or cancers affecting muscles. Unlike CT scans, MRI doesn’t use radiation, which makes it a preferred choice for some patients.

Positron Emission Tomography (PET) scans, often combined with CT scans (PET/CT), are another imaging technique often used in cancer diagnosis. PET scans can show how well a person’s organs and tissues are functioning.

How does a CT scan complement other diagnostic tests?

Think of cancer diagnosis like solving a complex puzzle. Each test provides a different piece of the picture. 

  • Blood tests can indicate whether certain substances, called tumor markers, are elevated. 
  • Biopsies provide a definitive diagnosis by allowing microscopic examination of tissue. 
  • Physical exams give doctors a general sense of a patient’s health.

A CT scan complements these by providing detailed images of the internal structures of the body, helping to localize abnormal growths, understand their extent, and plan treatment. 

It works hand in hand with other tests, each giving your healthcare provider a comprehensive understanding of your health.

Getting Ready for Your CT Scan

It’s normal to feel worried about your upcoming CT scan. A lot of people feel that way. Your technologist and other medical professionals are trained to make you feel safe, supported, and worry free. 

What should I do before and after my CT scan?

Usually, you’ll be asked to change into a gown and to remove any jewelry, glasses, or any metal objects as these can interfere with the scan. 

If you have any medical devices or implants, make sure to inform the technologist. 

Most CT scans take about 30 minutes to an hour, but the actual scanning time is usually much shorter. 

You’ll be lying down on a table that slides into the scanner, and you’ll need to stay still during the procedure. Some people find it helpful to practice some calming breathing exercises beforehand, to help them stay relaxed and still.

After your scan, you can typically go about your day as usual. Check with your healthcare provider for what you should do after your scan.

If you were given a contrast dye to help improve the image quality of your scan, you might be asked to wait for a short time after the scan to ensure you have no adverse reactions. Drinking plenty of water can help flush the contrast dye from your body.

Are there any dietary restrictions before a CT scan?

Whether or not there are dietary restrictions before your CT scan largely depends on the type of scan you’re having. 

For some CT scans, you might be asked to fast (not eat or drink anything) for several hours before your appointment. This is particularly the case if a contrast material will be used, as it can interact with food in your stomach.

That said, it’s essential to stay hydrated, especially if a contrast dye is used. So if you’re allowed to drink water, please do so. 

If fasting is required, the medical team will provide you with detailed instructions. Remember, every detail counts, so make sure to follow their guidelines closely.

What should I talk about with my doctor before my CT scan?

Before your CT scan, it’s a good idea to have a chat with your doctor. Don’t hesitate to ask any questions you might have, no matter how big or small they may seem. 

Here are a few things you might want to discuss:

  • Why: Make sure you understand why you are having the CT scan and what your doctor hopes to learn from it.
  • What happens: Ask about what you can expect during the imaging procedure, including how long it will take, and whether you could be uncomfortable.
  • Prepping: Talk about how to prepare, including whether you need to change your diet or medication schedule.
  • Following up: Discuss what happens after the scan, including when and how you will learn the results.

Remember, your healthcare team is there to support you. They want to help you feel comfortable and confident, so don’t be shy about expressing your concerns.

What Happens During Your CT Scan

It’s important for you to know what to expect from your CT scan so you can get the best possible scan results. Let’s take a closer look at what will happen the day of your scan.

What can I expect during the CT scan procedure?

As you step into the room for your CT scan, you’ll notice a large, doughnut-shaped machine—that’s the CT scanner. 

You’ll lie on a narrow table that slides into the circular opening of this scanner. During the procedure, it’s important to lie still as movement can blur the images. 

The technologist, who can see, hear, and speak to you at all times, will be operating the scanner from a separate room.

The CT scan itself is painless. You might be asked to hold your breath for a few seconds to avoid any chest or abdomen movement, especially if these are the areas being examined. 

You’ll also hear the hum and whir of the machine as it works, so don’t be surprised by these sounds, which can be a little loud for some people. 

Please let your technologist know if you’re uncomfortable at any point during your scan.

How long does a CT scan for cancer diagnosis usually take?

On average, the actual scanning part of a CT scan takes about 10 to 15 minutes. Including preparation time—like changing into a gown, getting positioned on the table—the entire process usually takes about 30 minutes, and up to 1 hour.

Allow some buffer time for pre-scan check-in procedures and post-scan decompression. 

Also, if you used a contrast material during your scan, you might need to wait a little longer after the procedure so we can make sure you don’t have an adverse reaction to the contrast.

What is contrast material, and will I need it for my CT?

Contrast material, often referred to as contrast dye or contrast agent, is a substance used in medical imaging to improve the clarity of the images. 

It helps highlight specific areas inside your body, making them easier to see, and providing a sharper contrast between normal & abnormal tissues.

Contrast materials can be administered in various ways (swallowed, injected into a vein, or administered through a rectal enema) depending on the area being examined. 

If a contrast material is required for your scan, your doctor will inform you beforehand. They’ll also provide you with detailed instructions on what to do before and after the procedure.

How Your Doctor Uses a CT Scan to Make a Diagnosis

You know that your doctor will use the CT images to understand your health. But you might not understand what happens after your scan is complete.

This is the point where a healthcare provider will use CT results to diagnose whether someone has cancer or not. 

Let’s take a closer look at how doctors use CT scans to diagnose potential cancer.

What will my doctor do with my CT scan?

Once your CT scan is complete, a radiologist will examine the scan. They’ll analyze the different shades of black, white, and gray to understand what’s happening inside your body. 

The CT scan provides cross-sectional images of your body, like the slices of a loaf of bread. It’s these slices that give your doctor a detailed and layered view of your body, helping them to identify any unusual or abnormal growths, like tumors. 

By examining the size, shape, density, and location of these abnormalities, a medical professional can determine whether they are likely to be cancerous.

What happens if the CT scan shows possible cancer?

Finding out that your CT scan shows possible signs of cancer can feel overwhelming, but remember that a CT scan is just one of several pieces in the puzzle. 

If your healthcare provider identifies areas of concern in your scan, they will discuss the findings with you, and explain what they might mean.

While CT scans are excellent at detecting abnormal structures or growths, a CT can’t diagnose cancer. A CT can’t distinguish between cancerous (malignant) and non-cancerous (benign) tumors. 

Here’s the bottom line: no CT scan will definitely show cancer, so if a CT shows something suspicious, your doctor will order further tests to know whether it’s cancer.

Will additional tests happen after my CT scan?

Confirming a diagnosis might involve more detailed imaging tests, like an MRI or PET scan, which can provide different types of images and information about the suspicious area.

In some cases, a biopsy might be necessary. This is a procedure where a small sample of the suspicious tissue is removed and examined under a microscope. It’s the only definitive way to confirm if a tumor is cancerous or not. 

Rest assured that your doctor will discuss the next steps with you, explaining each procedure, what it entails, and why it’s recommended. 

And remember, each diagnostic test is a step forward in understanding your health better, and ensuring you receive the most appropriate care.

Discussing Your CT Results with Your Doctor

This is the hard part. Talking to your doctor about possible cancer can be extremely stressful and anxiety-inducing, but remember, a CT scan is just one test. 

No matter what your results say, we want to empower you with all the information you’ll need for an educated talk with your doctor. Take a few deep, deep breaths, and read on to learn more.

How can I get ready to talk about my CT results with my doctor?

Sometimes we need to ask for help from the people in our lives. You might find it comforting to bring a trusted person with you, like a family member or friend, for support. They can also help you remember what your doctor says.

Before your appointment, jot down all the questions or concerns you have. This way, you can ensure you don’t forget to ask anything important during the meeting. 

You might also want to request a copy of your CT report. Take some time to read through it, even if you don’t understand it yet, so that you’re familiar with it. 

Some patient-focused centers use tools like Scanslated to make CT results easy for everyone to understand.

When it’s time to talk to your medical professional, you can ask them about anything in your report that you don’t understand, like the medical terms.

If my doctor thinks I am cancer-free, what questions should I ask about my CT results?

If your doctor informs you that you’re cancer-free, you should still take this opportunity to discuss your health and any potential risk factors. 

You might want to ask these questions:

  • What were the results of my CT scan?
  • Is there anything of concern that I should keep an eye on?
  • What health lifestyle changes can I make to lower my risk of cancer?
  • How frequently should I get check-ups or screenings in the future?

If my doctor thinks I might have cancer, what questions should I ask about my health and healthcare?

If your doctor believes you might have cancer, take a deep breath, and take a little time to get your thoughts together. This is the time to take care of yourself, and to educate yourself, for the road ahead.

When you’re ready, start asking your doctor questions, whether they’re about your diagnosis or about what you can expect next. The more you know about your cancer diagnosis, the less you’ll have to fear, and you’ll be a stronger person for it.

Here are some questions to ask your doctor:

  • Can you explain my diagnosis in detail? What happens next?
  • What type of cancer do I have? What stage is it?
  • What other tests do I need? Why those tests?
  • What treatment options are available, and what do you recommend?
  • What are the risks and side effects of the treatments you want me to do?
  • How will this diagnosis and treatment impact my daily life?
  • Where should I go to get a second opinion?

What next steps should I take if my doctor thinks I could have cancer?

After you have gathered all the information you need, and after you’ve taken the necessary time to absorb this news, it’s time to take action.

Your healthcare professional will outline a course of treatment, which might include:

  • Diagnostic tests: If your CT scan suggests the possibility of cancer, the next step is often further diagnostic tests. These could include additional imaging tests like an MRI or PET scan, blood tests, or even a biopsy where a small sample of tissue is removed for examination under a microscope. 
  • Consultations with specialists: Based on the type of cancer suspected, your doctor may refer you to a specialist (like an oncologist, who specializes in cancer care). The specialist will review your test results, assess your overall health, and discuss potential treatment options with you.
  • Discussing treatment options: There are several types of cancer treatments available, including surgery, radiation therapy, chemotherapy, immunotherapy, targeted therapy, and others. Your treatment plan will depend on various factors like the type and stage of your cancer, your overall health, and your personal preferences. 
  • Seeking a Second Opinion: Many people seek a second opinion after a cancer diagnosis. A second opinion can confirm your diagnosis, provide more information, offer different perspectives on your treatment options, and give you peace of mind that you’re making the right decisions for your health.
  • Coping and Support: No matter what happens, please reach out to friends, family, or a mental health professional for emotional support. Many healthcare facilities also offer supportive care services, including counseling and support groups, which can connect you with others going through a similar experience.

Please remember to take great care of yourself. 

This includes eating a healthy diet, staying physically active as recommended by your doctor, getting plenty of rest, and continuing to engage in activities you love, so you can stay strong for the journey ahead.

How to Schedule a CT Appointment with Us

Reach out to us at American Health Imaging, and we’ll help you schedule an appointment at an imaging center near you, today. 

Did you know our CTs cost up to 60% less than what you pay at a hospital? 

We’re here to help you get the answers you need.

What role do CT scans play in cancer diagnosis?

CT scans generate detailed images of internal body structures, facilitating early detection, diagnosis, and staging of cancer.

CT scans are necessary when symptoms, physical exams, or other tests suggest possible cancer, helping confirm or rule out its presence.

Prepare by fasting for several hours before the scan, avoiding certain medications if instructed, and wearing comfortable, metal-free clothing.

During a CT scan, you lie on a moving table that slides into the CT machine, which takes multiple images of your body from different angles.

Post-scan, a radiologist assesses the images to create a report, which is then discussed with you by your doctor, outlining any findings and next steps.*

Generally, CT scan results are ready in a few days, as radiologists need time to analyze the images and compile a detailed report.*

If your CT scan results suggest cancer, promptly consult your doctor who will guide you on the next steps, possibly including further diagnostic tests or treatments.

To prepare, jot down your questions or concerns, bring along any pertinent medical documents, and be ready to discuss potential treatment options and further procedures.