About Me

If you or a loved one receives a breast cancer diagnosis, count on Tricia Merrigan, MD, FACS, for experienced and specialized breast surgery. Dr. Merrigan is a fellowship-trained and board-certified breast surgeon at Avera Medical Group Comprehensive Breast Care in Sioux Falls, SD.

Innovative Breast Cancer Surgical Procedures

Providing an effective breast cancer surgery is Dr. Merrigan’s first priority. She also strives to give women the best cosmetic result possible. She achieves this through specialized training in surgical procedures such as:

  • Electron-based intraoperative radiation therapy (IORT) – Includes radiation during surgery which may eliminate the need for additional radiation or shorten the course of radiation
  • Oncoplasty – Combines techniques for removing cancer along with plastic surgery methods to improve the appearance of breasts
  • Lumpectomy – Conserves the breasts while providing the same recurrence prevention as mastectomy
  • Nipple-sparing mastectomy – Preserves the nipple and skin of the breast for future reconstruction
  • Hidden Scar™ – Removes the tumor and a slight amount of surrounding tissue through a small incision

Dr. Merrigan was the first surgeon in South Dakota, Minnesota, Nebraska and North Dakota to receive Hidden Scar™ certification. "I’m dedicated to this approach," she says. "It takes a little extra effort and time to avoid making scars on the breast so that they heal nicely, but is well worth it for my patients."

Compassionate, Holistic Care for Women

"I really believe in our mission – caring for the patient as a whole," she adds. "Treating breast cancer at Avera is all about providing a team approach to care for the whole patient. It’s all about doing what’s best for each patient."

Active Lifestyle

In her free time, Dr. Merrigan likes to play games, go camping and enjoy the outdoors with her family. She also enjoys riding and showing horses.

Experience

Education

University of South Dakota Sanford School of Medicine, Vermillion

Residency

General Surgery; Iowa Methodist Medical Center, Des Moines

Fellowship

Breast Surgery Oncology; Akron General Medical Center, Accredited by the Society of Surgical Oncology

Certifications

American Board of Surgery

Reviews

We value patient feedback and are committed to providing you with information, so you can make informed decisions about your health care, physicians and other providers in your care journey. Patient ratings and comments are gathered from the post-visit experience survey. Learn more.

August 28, 2024
Dr Merrigan is a caring, supportive, and brilliant doctor.
August 17, 2024
One of the most competent and intelligent physicians I've ever met. Thank you.
August 14, 2024
Dr Merrigan is very empathetic, cares for her patients, and gives top quality care!
June 10, 2024
I have already referred Dr Merrigan to someone. She loved her too
April 27, 2024
I already have recommended Dr. Merrigan to others
April 21, 2024
Dr Merrigan is great! I feel so at ease with her! Sue , that did my mammogram was also fantastic!!
April 03, 2024
Dr Merrigan is super nice, understanding & really makes me comfortable... She makes going through this appointment & the last so much more easier. She explains everything, answers all my questions & talks me through my concerns. Dr Merrigan was also my surgeon, she did such a good job & I would recommend her to anyone needing this same type of care going through the issues I was having.
March 08, 2024
I have seen Dr. Merrigan twice now and these visits always have me a little nervous but she has always been very kind and attentive. I leave knowing I'm in the best hands with her and the radiologists at the breast center.
February 04, 2024
Dr. Merrigan presented options and listened to my concerns
January 17, 2024
Dr. Merrigan focused on me, and did a great job of including my husband.
January 14, 2024
Dr Merrigan Is the best!
December 20, 2023
Dr. Merrigan and her staff are true caregivers and truly care about you as a person and not just another patient.

Directory Disclaimers

This directory contains information about the provider members of Independent Health Care Associates, Avera Health and all Avera entities, members of the Avera Medical Group, and employed select providers with Avera McKennan, Sioux Falls, SD and Avera Marshall, Marshall, MN and physicians with hospital privileges at Avera St. Luke's, Aberdeen, SD; Avera Sacred Heart, Yankton, SD; Avera Queen of Peace, Mitchell, SD; Avera St. Mary's, Pierre, SD.

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