Cancer Detection in the Pelvis Using CT

Pelvic cancer detection is a critical aspect of preventive healthcare, focusing on identifying conditions in organs of the pelvic region like the bladder, rectum, liver, pancreas, spleen, kidneys, and prostate. Early detection dramatically improves treatment outcomes and survival rates.

Computed tomography (CT) scans are a tool used for screening and staging pelvic cancer, providing detailed images that help healthcare professionals assess tumor characteristics and potential metastases. These scans are particularly valuable for those individuals experiencing symptoms like unusual bleeding and pelvic pain or those with high genetic risk factors. 

By enabling precise diagnosis, CT scans can help develop targeted treatment strategies and improve patient prognosis.

What is a Pelvic CT Scan, and How Does it Work?

A pelvic CT scan is a specialized imaging technique that uses X-rays to create detailed cross-sectional images of the pelvic region¹. This non-invasive procedure can help to detect what is causing symptoms like pelvic pain or abdominal bleeding.

The technology involves a rotating X-ray tube and detectors that measure X-ray attenuation through different tissues². These measurements are then processed using tomographic reconstruction algorithms to produce virtual “slices” of the body.

The CT machine consists of a motorized table that moves the patient through a circular opening called the gantry³. Inside the gantry, an X-ray source and detector assembly rotate around the patient, typically completing a rotation in less than a second. As the X-rays pass through the body, detectors register the radiation that emerges, creating snapshots from various angles.

To improve the visibility of certain structures and enhance cancer detection, contrast dye may be used during a pelvic CT scan. This dye can be administered orally or intravenously, depending on the specific area of interest⁴. The contrast material helps highlight blood vessels, organs, and potential tumors, making them more distinguishable from surrounding tissues. This enhanced visibility is particularly useful for detecting and staging cancers in the pelvic region⁵.

CT scans of the pelvis are valuable diagnostic tools for detecting and evaluating various conditions in the pelvic region. They provide detailed cross-sectional images of the pelvic organs, including the bladder, rectum, liver, pancreas, spleen, kidneys, and surrounding structures. They are particularly useful for⁴:

1. Detecting pelvic cancers.
2. Assessing the spread of cancer and monitoring treatment effectiveness.
3. Diagnosing pelvic infections, such as appendicitis and diverticulitis.
4. Identifying kidney and bladder stones.
5. Evaluating pelvic pain and abnormal bleeding.

While CT scans offer high resolution and are faster than magnetic resonance imaging (MRIs), they do expose patients to ionizing radiation. MRI is usually the preferred choice for imaging organs like the uterus and ovaries, during pregnancy, when visualizing fat, and when observing functional information about tissues⁶.

For certain conditions, ultrasound may be preferred as an initial imaging method due to its lack of radiation exposure, though CT scans generally provide more detailed images for complex pelvic disorders⁷.

How Can a CT Scan Help Detect Pelvis Cancers? 

CT scans are valuable for diagnosing and evaluating various types of pelvic cancers.

Types of Pelvic Cancer Diagnosed by CT cancers

Cervical cancer, one of the most common gynecologic cancers, can be detected and staged using CT scans, which help assess tumor size, parametrial invasion (invasion of the tumor into the tissue surrounding the uterus), and lymph node status⁸. Other gynecologic cancers that can be identified include ovarian, uterine, vaginal, and vulvar cancers.

In addition, pelvic CT scans can detect:

1. Colorectal cancer
2. Rectal cancer
3. Bladder cancer
4. Prostate cancer
5. Testicular cancer

CT scans are particularly useful for determining the extent of cancer spread, evaluating treatment effectiveness, and guiding treatment plans. While CT scans are effective diagnostic tools, they are often used alongside other imaging techniques like MRI and positron emission tomography (PET) scans, as well as biopsies⁹.

Accuracy and Benefits of CT Scans for Cancer Detection

CT scans are valuable tools for detecting and evaluating carious pelvic cancer, with accuracy rates varying depending on the specific cancer type.

For cervical cancers, the overall staging accuracy is up to 80 percent, with a sensitivity of 62.5 percentfor stages I and II^10,11. Its sensitivity for colorectal cancer detection is 91.6 percent, with sensitivity for polyps under 6 mm ranging from 73-98 percent¹².  When combined with PET imaging, CT has an average accuracy of 75.8 percent for patients under 50 with ovarian cancer¹³. 

CT scans excel in:

1. Tumor visualization: Accurately depicting tumor shape, size, and location, revealing blood vessels feeding the tumor¹⁴.
2. Cancer staging: Providing detailed information for TNM (tumor, node, metastasis) staging, which is important for treatment planning¹⁵.
3. Treatment guidance: Assisting in biopsy procedures and monitoring treatment effectiveness.

The Process of a Pelvic CT Scan for Cancer Detection

While pelvic CT scans are typically conducted in the same way as a standard CT, there are some extra steps that you might need to take.

If you require a scan of the rectum, you may need to have an enema of contrast medium, which makes the outline of the bowel show up more on the scan¹⁴.

Before the scan: 

For some scans, you may need to fast for four hours, though clear fluids and medications are allowed^16,17. Diabetic patients can have a light snack but should avoid large meals. If contrast is required, you may need to drink water or a special liquid.

Wear comfortable, loose clothing and remove metal items. A hospital gown may be required. If contrast is used, an IV may be placed, or you may drink an oral contrast¹⁸. Inform your provider of allergies, pregnancy, medical conditions, or medications, especially metformin¹⁹. Let them know if you have an iodine allergy before contrast administration.

During and after the scan:

A CT scan is a quick and painless imaging procedure that provides detailed images of your internal organs and structures. It takes between 15-30 minutes, with actual imaging lasting 10-15 minutes. You’ll lie on a table that moves through a doughnut-shaped scanner, staying still during the process. 

As the scanner rotates, you’ll hear a whirring sound. The radiographer operates the machine from another room, but you can communicate with them anytime. You may need to hold your breath briefly for clearer images. If you feel anxious, inform the radiographer, who can advise you on how to stay calm.

After the scan, you can go about your day as usual. 

Safety and Risks

CT scans are considered safe and use low levels of radiation²⁰. The procedure is painless and non-invasive. While lying still might be uncomfortable for some, the scan itself doesn’t cause physical discomfort. 

CT scans use ionizing radiation, which can damage tissues and slightly increase cancer risk²¹. Low-dose CT (LDCT) scans are available to reduce exposure, particularly for routine screenings.

Some CTs might require contrast agents to improve imaging but may not suit those with allergies or kidney issues²². Alternatives like ultrasound, MRI, or non-contrast imaging may be used instead.

When is a CT Scan of the Pelvis Recommended?

A CT scan of the pelvis may be recommended when some symptoms or conditions require detailed imaging of the pelvic region. 

Symptoms include⁴:

• Unexplained pelvic pain
• Abnormal bleeding
• Blood in stool or urine
• Urinary or bowel changes
• Unusual weight loss

Medical conditions include²³:

• Suspected abdominal or pelvic masses
• Infections and inflammatory conditions in the pelvis
• Kidney and bladder stones
• Abdominal aortic aneurysms

Cancer-related reasons might include:

• Detection and staging of pelvic cancers
• Monitoring cancer treatment effectiveness
• Evaluating metastatic spread

Other indications that might lead to a pelvic CT include:

• Pelvic trauma or injuries
• Postoperative follow-up
• Pre- and post-transplant evaluation
• Congenital abnormalities

For high-risk individuals with a family history of pelvic cancers, genetic predisposition, or previous cancer, a CT scan may be recommended as part of their screening or follow-up protocol. It should be noted, however, that for cervical cancer screening specifically, Pap tests and HPV tests are the primary methods used rather than CT scans^24,25.

Scheduling a Pelvic CT Scan: What to Expect

The average cost of a pelvic CT can range from $1,700 to $10,200²⁶. The factors affecting CT scan costs include the type of facility (inpatient centers cost more than outpatient centers), whether you are insured or how much of the procedure your insurance plan covers, and the location where you are getting your CT scan.

Insurance typically covers cancer-related imaging, but out-of-pocket expenses depend on deductibles, copays, and coinsurance. High costs can delay follow-ups even for insured patients. 

Conclusion

Detection of pelvic cancers through CT scans is important for improving treatment outcomes and survival rates. These scans provide detailed imaging, allowing for accurate diagnosis, staging, and monitoring of pelvic cancers. Timely screening can lead to early intervention, significantly increasing the chances of successful treatment. If you experience symptoms such as pelvic pain, abnormal bleeding, or other concerning changes, or if you have risk factors for pelvic cancer, consider scheduling a CT scan. Prioritizing early detection can make a life-saving difference.

If you are experiencing symptoms or have risk factors for pelvic region cancers, why not book an Ezra Full-Body Plus scan? We combine MRI with LDCT to catch potential cancer earlier, leveraging AI through the screening process to make it more efficient, affordable, and faster.