Cervical cancer is a type of cancer that begins in the cells of the cervix, which is the lower, narrow part of the uterus that connects to the vagina. It often develops slowly over time, with abnormal cells appearing before cancer fully forms. An ultrasound is a non-invasive imaging technique that uses high-frequency sound waves to create images of internal body structures.
Role of Ultrasound in Early Stage Assessment
While a biopsy remains the definitive method for diagnosing cervical cancer, ultrasound serves as a valuable complementary tool, particularly in assessing the local spread and extent of the disease in its early stages. Ultrasound is also used in pretreatment planning and evaluating tumors. Ultrasound can help determine the approximate size of a tumor, often appearing as a hypoechoic, heterogeneous mass within the cervix.
Ultrasound also aids in evaluating the depth of tumor invasion into the cervical stroma and can assess involvement of nearby tissues, such as the parametrium. It can detect signs of tumor invasion into adjacent organs like the bladder or rectum, though its sensitivity for small lesions in these areas may be limited. Additionally, ultrasound can identify hydronephrosis, indicating more advanced disease. Ultrasound can also assess pelvic lymph nodes, although its limitations in detecting very small metastatic lesions within non-enlarged nodes are recognized, often requiring further investigation with other imaging techniques like CT or PET-CT for comprehensive lymph node status.
How an Ultrasound is Performed
An ultrasound examination for cervical cancer involves two main approaches: transabdominal ultrasound (TAS) and transvaginal ultrasound (TVS). For transabdominal ultrasound, gel is applied to the lower abdomen, and a handheld probe, called a transducer, captures images. This method provides a broader view of the pelvic organs.
A transvaginal ultrasound offers a more detailed view of the cervix and surrounding pelvic organs due to its closer proximity. During this procedure, the patient lies on their back with knees bent, similar to a pelvic exam. A thin, lubricated probe covered with a sheath is inserted into the vaginal canal. The probe emits sound waves that bounce off internal structures, and the echoes are converted into images displayed on a computer monitor.
What an Ultrasound Can Show
Ultrasound can reveal details about the cervix and potential cancerous changes. It can visualize the cervix and uterus, identifying tumors if large enough. Tumors appear as areas with different echoes compared to healthy tissue, sometimes showing increased blood flow with color Doppler.
It can also help assess the approximate size of the tumor and its spread to the parametrial tissues. This helps determine the local extent of the disease. Ultrasound can detect hydronephrosis, a swelling of the kidneys caused by tumor growth obstructing the ureters, which suggests a more advanced stage of disease. It can identify suspicious enlarged lymph nodes in the pelvic region, though it may not detect very small cancerous deposits.
Understanding Ultrasound Results and Next Steps
Ultrasound findings provide valuable information, serving as one component in the overall assessment of cervical cancer. They contribute to clinical staging, helping healthcare providers understand the cancer’s spread.
After an ultrasound, healthcare providers discuss findings with other test results, such as Pap smears, HPV tests, and colposcopy. This comprehensive evaluation may lead to recommendations for further imaging for more detailed staging or to assess distant spread. Additional imaging tests, such as MRI, CT, or PET-CT scans, offer different perspectives on tumor characteristics and spread. This approach helps determine the most appropriate course of action, which may include further diagnostic procedures or treatment.