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Dr. Mark Casillas Jr, MD

Colorectal Surgery ·  Male · Age 41

Dr. Casillas Jr

University Colon and Rectal Surgery

1934 Alcoa Hwy Ste D370 Knoxville, TN 37920

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Dr. Mark Casillas Jr, MD is a colorectal surgery specialist in Knoxville, TN and has been practicing for 7 years. He graduated from University Of Alabama At Birmingham in 2006 and specializes in colorectal surgery and general surgery.

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(865) 305-5335

Dr. Casillas Jr accepts the following insurance:

Choice Plus POS II
Open Access
Blue Cross Blue Shield
Blue Card PPO
Cigna HMO
Cigna PPO
Commercial Insurance Company
Emblem Health
First Health (Coventry Health Care)
First Health (Coventry Health Care) PPO
Choice Care Network PPO
Choice Care PPO
Mail Handlers Benefit Plan (MHBP)
TriCare for Life
Choice Plus POS
Navigate HMO
Navigate POS
Options PPO

Background Check

No malpractice claims found for Tennessee
No disciplinary actions found for the years we collect data
No board actions found for the years we collect data
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Experience Check

Check Dr. Casillas Jr' experience treating your condition or procedure

Dr. Casillas Jr' Top Procedures and Conditions

Treatment Frequency
Anal Disorders
very high
very high

Treatment Frequency

Dr. Casillas Jr treats Anal Disorders more than 100% of his peers

Dr. Casillas Jr treats this condition more than 100% of his peers

Excision of Rectal Tumor
very high
very high

Treatment Frequency

Dr. Casillas Jr performs Excision of Rectal Tumor more than 99% of his peers

Dr. Casillas Jr performs this procedure more than 99% of his peers

Anal or Rectal Pain
very high
very high

Treatment Frequency

Dr. Casillas Jr treats Anal or Rectal Pain more than 99% of his peers

Dr. Casillas Jr treats this condition more than 99% of his peers

Dr. Casillas Jr' conditions and procedures:

  • Abdominal Disorders
  • Abscess
  • Abscess Incision and Drainage
  • Abscess or Cyst Drainage or Aspiration
  • Abscess or Fluid Incision and Drainage
  • Advanced Laparoscopic Surgery
  • Anal and Rectal Cancer
  • Anal Cancer
  • Anal Disorders
  • Anal Fissure
  • Anal Fistula
  • Anal or Rectal Pain
  • Anal Prolapse
  • Anorectal Abscess
  • Anorectal Myomectomy
  • Anoscopy
  • Anoscopy With Removal of Anal Tumor
  • Appendectomy, Laparoscopic
  • Appendectomy, Open
  • Appendicitis
  • Appendix Cancer
  • Cancer
  • Carcinoma in Situ
  • Colectomy
  • Colectomy and Sigmoidectomy With Robotic Assistance
  • Colon and Rectal Surgery
  • Colon Cancer
  • Colon Cancer Screening
  • Colon Disorders
  • Colon Polyp
  • Colon Surgery
  • Colonic Diverticulosis
  • Colonoscopy
  • Colonoscopy With Polypectomy
  • Colonoscopy, Proctosigmoidoscopy, and Sigmoidoscopy
  • Colorectal Cancer
  • Colorectal Cancer Screening
  • Colorectal Cancer Treatment
  • Colorectal Polyp
  • Colorectal Surgery, Robotic-Assisted
  • Constipation
  • Crohn's Disease
  • da Vinci® Colectomy
  • da Vinci® Robotic Surgery
  • Destruction of Anal Tumor
  • Diverticulitis
  • Dressing and-or Debridement of Wound, Infection, or Burn (incl. Negative Pressure Wound Therapy)
  • Endoscopy
  • Enterostomy (Laparoscopic or Open)
  • Excision of Rectal Tumor
  • Familial Colorectal Cancer
  • Familial Polyposis
  • Familial Polyposis, Classical
  • Fecal Incontinence
  • Fissures
  • Fistulectomy or Fistulotomy, Anal
  • Flexible Sigmoidoscopy
  • Flexible Sigmoidoscopy With Robotic Assistance
  • Gastroenterologic Cancer (Colon, Stomach, Esophageal, Liver)
  • Gastroenterology Procedures
  • Gastrointestinal Diseases
  • Gastrointestinal Surgery
  • Hemicolectomy
  • Hemorrhoid Removal
  • Hemorrhoid Treatment
  • Hemorrhoidectomy or Excision of Anal Tags
  • Hemorrhoids
  • Hereditary Nonpolyposis Colon Cancer
  • Hernia Repair
  • Ileal Pouch-Anal Anastomosis
  • Incision and Removal of Foreign Object
  • Incisional Hernia Repair, Laparoscopic
  • Incontinence Surgery
  • Inflammatory Bowel Disease
  • Interstim® Sacral Nerve Stimulator
  • Intestinal Abscess
  • Intestinal Obstruction
  • Intestinal Transplant (incl. Enterectomy)
  • Laparoscopic Abdominoperineal Resection of the Rectum With Robotic Assistance
  • Laparoscopic Colectomy
  • Laparoscopic Colon Surgery
  • Laparoscopic Rectal Surgery
  • Laparoscopic Sigmoidectomy With Robotic Assistance
  • Laparoscopic Surgical Procedure
  • Laparoscopy
  • Meckel's Diverticulum
  • Minimal Access Surgery
  • Minimally Invasive Surgery
  • Neuroendocrine Tumors
  • Open Incisional and-or Ventral Hernia Repair
  • Paracentesis
  • Pelvic Exenteration (For: Gynecologic, Urinary, or Colorectal Malignancy)
  • Pilonidal Cyst
  • Proctectomy, Open or Laparoscopic (incl. Swenson and Duhamel Procedures)
  • Proctosigmoidopexy With Robotic Assistance
  • Rectal Abscess
  • Rectal Bleeding
  • Rectal Cancer
  • Rectal Diseases
  • Rectal Prolapse
  • Rectal Surgery
  • Rectal-Colon Bleeding
  • Rectovaginal Fistula
  • Rectovaginal Repair
  • Removal of Reproductive Organs (Hysterectomy, Oophorectomy, Salpingectomy, Salpingo-Oophorectomy, Resection of Peritoneal Malignancy)
  • Removal or Destruction of Rectal or Intestinal Tumor (incl. Colonoscopy, Proctosigmoidoscopy, Sigmoidoscopy and Control of Hemorrhage)
  • Repair of Anal and Rectal Defects (Anoplasty, Repair of Imperforate Anus, Sphincteroplasty, Rectal Graft)
  • Repair of Rectocele With Robotic Assistance
  • Restorative Proctocolectomy With Ileal-Anal J Pouch
  • Rigid Proctosigmoidoscopy With Robotic Assistance
  • Rigid Sigmoidoscopy
  • Secondary Malignancies
  • Sigmoid Colectomy
  • Sigmoidoscopy
  • Skin Lesion Removal
  • Small Bowel Surgery
  • Snare Polypectomy
  • Sphincterotomy
  • Surgery, Robotic Assisted
  • Surgical Procedures
  • Tumor Resection
  • Ulcer
  • Ulcerative Colitis
  • Ulcerative Proctosigmoiditis

About Me

Care Philosophy We provide the full spectrum of colorectal surgical care but our services extend beyond the operating room. We pledge to treat you with dignity and respect, to communicate with you clearly and honestly, to protect your confidentiality, and to earn your trust.


  • Colorectal Surgery
  • General Surgery

Board Certifications

  • Colon & Rectal Surgery
  • General Surgery


Indiana School Of Medicine-Colon & Rectal Surgery Residency
Fellowship Hospital
St. Joseph Mercy Hospital-General Surgery Residency
Residency Hospital
Brown University School Of Medicine
Internship Hospital
University Of Alabama At Birmingham
Medical School
University Of Alabama
Undergraduate School


Dr. Casillas Jr' Reviews

Likelihood to recommend Dr. Casillas Jr


Based on 29 reviews

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Average Reported Wait Time
  • 10 – 15 minutes
Dr. Casillas Jr' Performance
  • Trustworthiness
  • Explains condition(s) well
  • Answers questions
  • Time well spent
Office & Staff Performance
  • Scheduling
  • Office environment
  • Staff friendliness
What People Say About Dr. Mark Casillas Jr, MD
Fantastic doctor, Explains everything in detail and asks is you have questions and he listens to you.
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Dr. Casillas took over practice of Dr. Julio Solla whom I used for 15 years. Dr. Casillas is incredibly thorough, very "patient sensitive" and is another one of the exceptional bright Stars at UT Medical. It takes a very special physican to practice in the Colon / Rectal arena, he's tops. Had a recent colonoscopy, he was very thorough with diagnosis to find diverticulitis, discussed treatment options, etc. Engages and listens to patient very well. Highly recommend.
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Dr. Camilla’s is an expert in his field of medicine. He is through in his exam, explanations. He has a great bedside manner. My surgery had a very good outcome. I’m glad he was my doctor.
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This doctor is very professional and caring. Did my surgery 6 days ago and so far it looks like he did a great job. Very recommend him to others. ??????
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