Stacey R. Zavala MD
Meet the Doctor

Talking About Colon Cancer Screening With Stacey R. Zavala, MD

By on 03/26/2019

Preventive care and screenings can catch colon cancer in its earliest stages. In recognition of Colon Cancer Awareness Month, gastroenterologist Stacey R. Zavala, MD, Associate Chair, Division of Gastroenterology, and Program Director, Gastroenterology Fellowship Program, shares information about screenings and colonoscopy preparation.

Q: Why did you choose gastroenterology as a career?
A: My first exposure to gastroenterology was as a young girl. My grandmother was diagnosed with metastatic colon cancer at the age of 58. Unfortunately, she lost her fight, but I wanted to find a way to prevent others from going through what my grandmother and family went through. In medical school, I was trying to find my path. I had the opportunity to work with a female gastroenterologist, Dr. Maureen Lillich. I was amazed by her career and personal life. One day she would be in the office seeing patients; another day she would be in the hospital seeing consults; and twice a week she would be performing procedures. It was never the same day. She also showed me it was possible to balance family and work. After working with her, I was inspired to pursue my dream to become a gastroenterologist.

Q: What is your education background?
A: I was born and raised in Stockton, California. I completed my Bachelor of Science degree in Physiological Sciences at University of California, Los Angeles. I attended medical school at the University of Illinois, Chicago, Peoria campus. After medical school, I decided to follow my family to Philadelphia, where I completed both my residency and fellowship at Albert Einstein Medical Center.

Q: Can you explain the importance of colonoscopy and colorectal cancer screening?
A: Colorectal cancer is the third most common cancer in both men and women in the U.S., and it is the second most common cause of cancer deaths. Screening efforts for colorectal cancer have decreased the number of deaths. Colonoscopy allows physicians to identify adenomatous colon polyps, which are the precursors to colon cancer, and remove the lesions before they grow into cancer. This decreases the risk for colon cancer significantly.

Q: Can you explain how exams detect problems or conditions in their early stages?
A: There are stool-based tests, radiologic and endoscopic procedures that are available for colorectal cancer screening.

  • Stool-based tests
    — FIT (fecal immunochemical testing): This test identifies hidden blood in the stool by identifying the human hemoglobin protein. Polyps and cancer may have passage of blood as stool passes through the colon.
    — Guaiac-based stool tests: Similar to the FIT test, this test identifies blood in the stool through a chemical reaction.
    — Stool DNA testing: This test looks for certain abnormal sections of DNA from cancer or polyp cells. Colorectal cancer or polyp cells often have DNA mutations (changes) in certain genes. Cells with these mutations are shed into the stool, where tests may be able to detect them.
  • Colonoscopy: This is an endoscopic procedure that is completed after a patient takes a bowel preparation to clean the colon. The patient is sedated, and a small flexible tube with a light and camera on the end of it is inserted into the rectum and advanced through the colon. Physicians perform a careful exam to identify and remove colon polyps.
  • Flexible sigmoidoscopy: An endoscopic procedure that evaluates the left colon only.
  • CT colonography: This is an advanced type of computed tomography (CT) scan of the colon. A CT scan uses x-rays, but instead of taking one picture, like a regular x-ray, a CT scanner takes many pictures as it rotates around you while you lie on a table. A computer then combines these pictures into detailed images of the part of your body being studied. For CT colonography, special computer programs create both two-dimensional x-ray pictures and a three-dimensional view of the inside of the colon and rectum, which lets the doctor look for polyps or cancer. Patients still need to take a bowel prep for this test. If these tests are positive, it is recommended that the patient undergo colonoscopy.*

Q: There are some myths and fears about the preparation for a colonoscopy. Is it hard to prepare for a colonoscopy?
A: The most common fear about colonoscopy is taking the bowel preparation. Many patients have heard horror stories from their friends and family, whether it is drinking a gallon of salty water to spending the night on the toilet.

Patients are instructed to adhere to a clear liquid diet the day before the procedure. Then they take a bowel preparation, in a split-dose fashion, the evening before and the morning of the test. Today there are a number of low-volume bowel preparations available.

I frequently encourage patients to mix the bowel preps with things that are palatable and to keep the solution cold. Some choose to drink the preparation through a straw. It is also extremely important to stay well hydrated throughout the process. I recommended making sure there are plenty of your favorite liquids readily available to you throughout the prep day. Some of these tips will make the preparation easier.

Q: What exciting opportunities are on the horizon for gastroenterology at Einstein?
A: There are some exciting things happening for Einstein Gastroenterology. Our Direct Access Colonoscopy Program continues to grow across the suburban and urban core. If patients pass a set of screening questions, they may skip the office visit and schedule for the procedure. Our new Ambulatory Surgery Center in Blue Bell has opened at 676 DeKalb Pike, Suite 101, in February 2019. This is located next to our office space in Suite 102.

Physician 411

  • Specialty: Gastroenterology
  • Interests: Swallowing disorders
  • Favorite vacation spot: Italy
  • Person most interested to meet: Michelle Obama
  • Early role model: Grandmother; she was the vice president of a large company
  • Favorite book: The House of God, by Samuel Shem
  • Interesting fact: I am vegan

Interested in learning more about colon cancer screening? Make an appointment to see an Einstein physician.

*Source: “American Cancer Society Updates Colorectal Cancer Screening Guideline,” American Cancer Society, May 30, 2018,



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