Diagnosing Cancer

Overview
An early diagnosis of cancer is important, as it can significantly impact patient outcomes and treatment options. At Cleveland Clinic Abu Dhabi, our team of specialists offer the latest diagnostic techniques, including AI-powered imaging tools and sophisticated multicancer early detection (MCED) tests, to detect cancer at its earliest stage, allowing for timely intervention and improved chances of successful treatment.
Cancer can be diagnosed using a range of diagnostic methods. Your doctor will first perform a physical examination to look and feel for abnormalities that may indicate cancer. They will also discuss your medical history and any symptoms you are experiencing with you in detail. They will then decide on the most appropriate type of diagnostic test, which will depend on the type of cancer being tested for, its location, the patient’s overall health, and many other factors.
Some types of cancer may only require one or two tests to accurately confirm a diagnosis, while others may require additional tests. The most commonly used diagnostic methods are imaging, biopsy, blood tests and endoscopy.
Imaging Tests
Imaging tests, or scans, allow doctors to see a picture of what is happening inside your body and whether a tumor is present. There are several ways that these images can be obtained, from simple X-rays to highly detailed cross-sectional imaging machines.
Ultrasound
Ultrasound uses high-frequency sound waves to create real-time images of organs and tissues. As well as detecting tumors, ultrasound can be used to guide biopsies.
X-Rays
X-rays use low doses of radiation to create pictures inside your body. A technician will ask you to stay very still while they direct radiation beams at the area of your body being tested.
Computed Tomography (CT) Scan
A CT scan uses a combination of X-rays and computer technology to create detailed, cross-sectional images of the body. It helps identify tumors, abnormal masses, and changes in organ structures, and helps in the diagnosis and staging of various cancers.
Magnetic Resonance Imaging (MRI)
MRI uses powerful magnets and radio waves to generate detailed images of internal organs and tissues. It is particularly useful in assessing soft tissue structures and is commonly used for brain, spinal, and musculoskeletal cancer diagnostics.
Nuclear Scan
A nuclear scan or radionuclide scan, uses radioactive material, which is injected into the bloodstream, to take pictures of the inside of the body. The radioactive ‘tracer’ travels through the blood and around the body, collecting in certain areas. A scanner then detects the radioactivity in the body and creates an image on a computer. Any radioactivity in the body is lost over time and can leave the body via urine or stools.
Bone Scan
A bone scan is a nuclear imaging test that helps identify areas of abnormal bone growth or metastasis in patients with suspected or diagnosed cancer. It is especially useful for assessing bone involvement in various types of cancer.
Positron Emission Tomography (PET) Scan
A PET scan is also a type of nuclear scan. It produces detailed 3-D images of the areas in the body where glucose is taken up. A tracer called radioactive glucose is injected and a scanner is then passed over the body. As cancer cells take up more glucose than normal cells, they will show up on the scan and help doctors identify cancer in the body.
PET-CT Scan
Combining PET and CT imaging, a PET-CT scan is used to detect, stage and monitor cancer. It is an effective tool for locating tumors, assessing spread, monitoring treatment effectiveness and detecting recurrence.
AI-Powered Imaging Tools
AI-powered imaging tools can enhance the accuracy, speed and consistency of tumor detection. The tools, which can be applied to a number of imaging modalities, including mammography, CT, MRI and PET scans, are revolutionizing cancer diagnosis. The AI systems utilize deep learning to identify subtle and early-stage cancers, that may not be detected by traditional imaging tools.
Biopsy
A biopsy involves the removal of tissue or a sample of cells from the body so that they can be examined under a microscope for signs of cancer. A biopsy can also identify the specific type of cancer present. While imaging tests can detect masses or irregular tissue, they cannot confirm whether cells are cancerous or not. A biopsy is often the only way to confirm cancer.
There are several ways in which a biopsy can be performed:
Needle Biopsy
A minimally invasive procedure, a needle biopsy involves inserting a very thin needle through the skin to extract tissue or fluid from a suspected tumor for analysis. Needle biopsies are commonly used for breast, lung, and prostate cancers. If the suspicious area can’t be felt under the skin, an imaging tool may be used to guide the needle. There are several types of needle biopsy:
- Fine-needle aspiration: A fine needle is inserted to draw out cells or fluid.
- Core needle biopsy: A larger needle with an edge that can remove tissue.
- Vacuum-assisted biopsy: A needle is inserted, and a vacuum is applied which can suck out more cells or fluid if needed.
- Image-guided biopsy: Imaging procedures such as ultrasound or CT scans are used to help guide the needle in areas where the tumor can’t be felt, such as the lung or liver.
Endoscopic Biopsy
During an endoscopy (see below), tools are passed though the endoscope which can remove tissue samples from inside organs, such as the bladder, colon or lung.
Skin Biopsy
Usually used in suspected skin cancer cases, skin biopsies involve the removal of cells from the skin’s surface. There are several types of skin biopsy:
- Punch biopsy: A small device removes deeper layers of the skin.
- Shave biopsy: A razor-like instrument shaves off the top layer of skin.
- Incisional biopsy: A scalpel removes layers of skin, and stitches may be required to close the wound afterwards.
- Excisional biopsy: The whole area of suspicion is removed, and stitches are usually required to close the wound.
Surgical Biopsy
If the cells that the doctor wants to analyze are hard to reach, and none of the above methods are suitable, then a surgical biopsy may be needed. The procedure involves making incisions so a surgeon can access the area and remove cells or an entire mass. Most surgical biopsies can be performed with local anesthetic, but some may require a general anesthetic.
Bone Marrow Biopsy
If your doctor suspects a cancer that is affecting the bone marrow, then a bone marrow biopsy may be needed. The sample of tissue is taken via a needle from the back of the hip bone, or from other bones if necessary. Bone marrow biopsies are used to diagnose blood cancers and can detect if cancer from other areas has spread to the bone marrow.
Blood Tests
By taking a sample of blood, doctors can diagnose some cancers, as well as check your overall health and the function of certain organs such as the liver and kidneys. When the blood is analyzed in a laboratory, it can show the types of cells, proteins and chemicals in the blood. There are different types of blood tests, including:
Complete Blood Count (CBC)
A CBC measures the number of different blood cells, such as red and white blood cells and platelets. Abnormalities in blood cell counts (the number present) can indicate certain types of cancer or potential complications.
Tumor Markers
Tumor markers are substances found in the blood that may be elevated in the presence of certain cancers. While they are not definitive for cancer diagnosis, they can provide valuable information to aid in screening and monitoring treatment.
Liver Function Tests (LFT)
LFTs show how well the liver is working. Enzymes and proteins, which are made or cleared by the liver, will show up in the blood test and can indicate issues with the liver, bile duct or gallbladder. There are many non-cancerous conditions that can also affect an LFT.
Urea and Electrolytes
Blood tests for urea, electrolytes and a substance called creatinine, which the kidneys remove from the body, can indicate a kidney problem.
Multi-cancer early detection (MCED) tests
MCED tests are blood tests that can identify markers that may indicate cancer. It is a type of liquid biopsy, a test that uses blood or other bodily fluids, to detect cancer. The test looks for circulating cancer markers in blood samples. An emerging technology within the field of cancer detection, MCED tests use machine learning to identify cancer at an earlier stage when it may be easier to treat, before any symptoms appear.
Endoscopy
An endoscopy involves inserting an endoscope – a long, thin, flexible tube with a camera and light on the end – into the body (usually via the mouth) so that doctors can see inside. There are many types, each used for looking at different parts of the body. During an endoscopy, a biopsy of tissue may also be taken (see biopsy above). Endoscopies are also used to assess and treat many other non-cancerous conditions.
Upper Endoscopy
This procedure allows a doctor to examine the esophagus, stomach, and upper part of the small intestine. It is commonly used to detect and diagnose gastrointestinal cancers.
Colonoscopy
During a colonoscopy, the endoscope is used to examine the colon and/or rectum. It is an important tool for detecting colorectal cancer and precancerous growths.
Bronchoscopy
A bronchoscope is inserted into the windpipe and down into the airways, via the mouth or nostril. A local anesthetic may be given, or if a larger tissue sample is needed, then you may be given a general anesthetic.
Cystoscopy
A cystoscope is inserted into the urethra and then into the bladder. It is used to detect problems associated with passing urine and is an important test for diagnosing bladder cancer.
Once diagnostic tests have been performed, experts from our Cancer Institute work collaboratively to interpret test results accurately and provide comprehensive, individualized care plans for each patient.
It’s important to remember that regular cancer screenings and awareness of potential symptoms play a vital role in ensuring that cancer is diagnosed at its earliest, most treatable stage.
Always talk to your doctor if you notice anything unusual.
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