Board of Directors

Shauna Lorenzo-Rivero, MD

Chairman of the Board

Years on the Board: 12 

I am a colorectal surgeon in Chattanooga, TN. Everything I do is to make patients healthy and happy by improving the health of their GI tract through surgery. I believe every human being should have access to health care. Healthy people are happy people. This is why I started the Greater Chattanooga Colon Cancer Foundation(GCCCF) to raise funds for those who cannot afford screening colonoscopy and educate our community on the importance of colon cancer screening. Colonoscopies save lives!

Colorectal Surgeon

University Surgical Associates

Tom Brien, MD

Board President

Years on the Board: 12

As a GI Pathologist, I deal with colon biopsies every day.  It makes me sad every time I have to diagnose cancer because I know that screening saves lives.  I joined the GCCCF to help raise awareness in our area about the importance of colon cancer screening.  I also dress up as the superhero Captain Colon for the Rump Run and other events to hopefully make people more comfortable talking about a part of the body they too often choose to ignore.

Pathologist, Diagnostic Pathology Services

Marshall Horton, MD

Board Vice President

Years on the Board: 8

After retiring from the practice of gastroenterology, I wanted to give back to the community through volunteerism. During my 30 year career, I saw so many people with colon cancer that could have been avoided or found earlier with timely screening.  The GCCCF was an opportunity to spread the word “Colonoscopies Save Lives.”
Retired Gastroenterologist,
Galen GI

Years on the Board: 5

I am very committed to the GCCCF for giving me an opportunity to continue to serve the community by volunteering and sharing my passion of giving back to my community. I am very passionate about the organization’s mission to educate the public about how colonoscopies save lives; as well as its specific target of reaching vulnerable communities of color with this message who are at a high risk of dying from this devastating, yet preventable disease.

Retired Grants, Health Education & Site Manager

 Erlanger Community Health Centers

Craig Sarine

Years on the Board: 12

I am the CEO of a Chattanooga based surgical group which includes five colon and rectal surgeons as well as several general surgeons who perform many colon and rectal procedures as well.  While I do not have any family members who have been diagnosed with this disease, I had a friend who passed away from an undiagnosed rectal cancer because he put off routine screening until it was too late.  I serve on the GCCCF board to help our community avoid the emotional pain and, quite frankly, the frustration and disappointment of such needless loss.
Practice Administrator,
University Surgical Associates

Alison Sexter

Years on the Board: 3

I’m passionate about the efforts of GCCCF in part because of all the people I know who have been impacted by the disease - especially my beloved grandmother who our family lost to colon cancer 12 years ago.
Corporate Communications Specialist, Public Affairs, BCBST

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