Rectal and Anal Cancer Screening & Diagnosis

We offer advanced screening options for rectal and anal cancer.

Rectal cancer is a relatively common disease in the United States. It affects about 40,000 people each year. Anal cancer is less common, but can be aggressive.

Your doctor may detect cancer during a routine examination or during a colonoscopy or other screening exam. Our rectal and anal cancer specialists are experienced in the diagnosis and treatment of all stages of rectal cancer and anal cancer.

Once we confirm a diagnosis, we create a treatment plan based on the stage of cancer. We use diagnostic and screening tests to evaluate tumors. Then we identify the most effective treatments with the least impact on your quality of life.

Rectal and anal cancer screening

Our team treats rectal and anal cancer at any stage. We offer colorectal cancer screening, such as colonoscopy, to aid in diagnosis.

A doctor who suspects rectal or anal cancer may order one or more of the following:

  • Fecal occult blood test (FOBT): A lab test to check for blood in the stool. This test can help detect early rectal cancer.
  • Anoscopy: A doctor will use a small, lighted scope to look inside the anus.
  • Digital rectal exam (DRE): The doctor inserts a lubricated, gloved finger into the rectum to feel for cancer on the rectal wall.
  • Endoscopy: A doctor inserts an endoscope (a flexible tube with a camera) through the anus and into the rectum and colon to view and remove abnormalities on the inner lining of these organs.
  • Rigid sigmoidoscopy: A doctor uses a stiff optical scope to measure a tumor’s distance from the anus.
  • Carcinoembryonic antigen (CEA): A blood test that measures the CEA level. If it is higher than normal, it may be a sign of rectal cancer.
  • Biopsy: A biopsy is a sample of suspicious cells. In the lab, scientists analyze the cells to help confirm if cancer is present.
  • Imaging tests: Your doctor may order tests to take pictures of the inside of your body. These tests include a CT (computed tomography) scan, ultrasound, or X-ray.

Staging rectal and anal cancer

When doctors diagnose rectal cancer, they identify the cancer’s stage. The stage is based on the size of the cancer and whether it has spread elsewhere in the body. Staging helps doctors choose the most effective treatment options for your condition.

Your doctor may prescribe chemotherapy or radiation therapy along with surgery. The combination of treatments can improve your outlook and help keep you cancer-free.

Rectal cancer stages

Rectal cancer is classified into these stages:

  • Stage 0: Cancer is in the lining of the rectum (mucosa), but it has not spread deeper into the rectal wall. This is also called carcinoma in situ.
  • Stage I: Cancer has not spread beyond the rectum wall.
  • Stage II: The tumor goes deeper into the rectum wall.
  • Stage III: Cancer has spread from the rectum to nearby lymph nodes or other organs.
  • Stage IV: Cancer has spread to distant parts of the body.

The treatment options depend on the stage of your rectal cancer.

Anal cancer stages

Anal cancer is classified into these stages:

  • Stage 0: Abnormal cells are found in the lining of the anus. This stage is also known as carcinoma in situ.
  • Stage I: Physicians identify cancer with a tumor that is 2 centimeters or smaller.
  • Stage II: A tumor is in the anal area, and the tumor is larger than 2 centimeters.
  • Stage IIIA: The tumor has spread to lymph nodes near the anus, or to nearby organs, such as the bladder, urethra, or vagina.
  • Stage IIIB: The tumor has spread to lymph nodes and nearby organs.
  • Stage IV: The tumor has spread to distant parts of the body.

Your doctor will base your treatment options on the stage of your anal cancer.

A team approach to whole patient care

Our team is here to educate and support you before, during, and after anal cancer or rectal cancer treatment. We’ll prepare you for what to expect during recovery and connect you with others who understand what you’re going through.

Connect with our Cancer Team 24/7

Call us at (888) 777-4167

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