Welcome to Rochester Colon & Rectal Surgeons, P.C.


Rochester Colon-Rectal Surgeons, P.C. is a group of surgical colon-rectal specialists committed to caring for people with problems of the intestinal tract. Our expertise includes the treatment of tumors/cancers of the colon, rectum and anus, diverticulosis/ diverticulitis, Crohn’s disease, Ulcerative Colitis (including J pouch surgery), anorectal problems (hemorrhoids, fissure, abscess, fistula, and warts, fecal incontinence). Preventative care is important to our group and we offer screening options that can help prevent colorectal and anal cancers.

Rochester skyline

What Our Patients Are Saying

5 Stars

May 7, 2021

Thank you for taking care of my urgent needs. Everything went very smooth. I am very pleased!
5 Stars

Apr 9, 2021

Dr. O'Neil was beyond great for my colonoscopy. I would highly recommend Dr. O'Neil for this procedure, she along with Tammy and Mike, worked patiently to accommodate my request for no sedation. I was surprised at how little discomfort I had during the procedure, and was delighted to get right up, have breakfast, and play a round of golf (by 9 am). Thank you for making this a very positive experience. If you need a great experience for your colonoscopy you should make an appointment with Dr. Mary Lou O'Neil, I'm sure you'll be very pleased with her and her staff. See you in 5 years!!!
5 Stars

Apr 6, 2021

I recently underwent a colonoscopy with Dr. O'Neill and the experience was truly exceptional. Dr. O'Neill was reassuring and explained everything thoroughly. She had been recommended to me because of her skill as a colorectal specialist and that, coupled with her easy going nature and delightful sense of humor, put me at ease. The nursing staff was outstanding as well.
5 Stars

Apr 1, 2021

Very relaxed atmosphere. Covid restrictions were followed and very good. Staff is very friendly. Didn't even feel anything when the nurse put the IV in my arm. Mike and Collene were great. Dr. O'Neill is the best.
5 Stars

Mar 29, 2021

I just had a colonscopy for the first time ever. Dr. Domajnko performed this procedure. He was awesome! I was so fortunate to be referred to him in the first place. I didn't feel a thing and thought it went quickly. I will go back to him, without hesitation, for any future needs regarding my colon/rectal health. Just a talented doctor and a terrific person!
Previous Slide Previous Slide
Next Slide Next Slide
Play Slider Play Slider
Pause Slider Pause Slider

Google Reviews


What's New at RCRS

african american woman

Colon Cancer Screenings: 45 Is The New 50

Colon Cancer Screenings: 45 Is The New 50

Several well-known medical entities have updated their colon cancer screening recommendations from age 50 to 45 for those with average risk. Recently, both the American Cancer Society and the United States Preventative Services Task Force (USPSTF) have made these changes due to the increasing numbers of young adults being diagnosed with colon cancer.

View All

Call us at (585) 222-6566