About me
Marcus Oosenbrug, MD, FRCSC, is a double-board-certified colorectal surgeon at MedStar Georgetown University Hospital, where he provides advanced surgical care for patients with benign and malignant diseases of the colon, rectum, and anus.
Dr. Oosenbrug treats the full spectrum of colorectal conditions, including colorectal cancer, inflammatory bowel disease (Crohn’s disease and ulcerative colitis), and diverticulitis; anorectal conditions, in particular hemorrhoids, fissures, fistulas, and anal dysplasia; and pelvic floor disorders such as rectal prolapse and fecal incontinence. Trained in minimally invasive techniques, including laparoscopic and robotic approaches, he strives to help patients recover more quickly and with less pain, while preserving normal function whenever possible.
Dr. Oosenbrug's clinical interests include complex inflammatory bowel disease and sphincter-preserving procedures such as J-pouch surgery. He is also passionate about LGBTQ+ health, and the early detection and treatment of anal dysplasia using high-resolution anoscopy (HRA), a proven method for reducing the risk of anal cancer in vulnerable populations. He is also trained in sacral nerve stimulation therapy (MedTronic Interstim™) for fecal incontinence.
Originally from Canada, Dr. Oosenbrug completed his medical degree at McGill University in Montreal and general surgery residency at the University of Toronto. Before joining MedStar Health, he completed a fellowship in Colon & Rectal Surgery, as well as an additional year of further advanced surgical training in minimally invasive and complex reoperative colorectal surgery at the Cleveland Clinic in Florida.
A strong advocate for patient-centered care, he is dedicated to fostering an inclusive, affirming, and respectful environment for all patients and works closely with multidisciplinary teams of gastroenterologists, oncologists, and gynecologists to deliver comprehensive, coordinated care.
Having adopted Washington, D.C. as his home, he enjoys traveling, exploring new restaurants, and discovering everything the diverse capital city has to offer.
Philosophy of Care
“I strive to treat every patient with the same honesty, compassion, and attention I would give my own family. Trust and continuity of care are essential in my field, and I want patients to know that I’m here to support them throughout their entire healing journey. I see myself as an advocate for my patients, and my goal is to create a welcoming environment where people from all walks of life can feel heard, supported, and empowered to make informed decisions about their care.”
Clinical areas of focus
- Abdomen, Lower Back, Pelvis, And Genital Open Wound
- Abdominal Pain
- Anoscopy With Biopsy
- Anus And Rectum Diseases
- Colon Cancer
- Crohn's Disease
- Crohn's Disease [Regional Enteritis]
- Functional Intestinal Disorders
- Gastrointestinal Bleeding
- Hemorrhoids
- Ulcerative Colitis
Conditions and procedures
Conditions I treat
- Abdomen, Lower Back, Pelvis, And Genital Open Wound
- Abdominal Pain
- Abnormal Digestive Findings
- Anal Abscess
- Anal Bleeding
- Anal Cancer
- Anal Itching (PRURITUS ANI)
- Anal Warts (CONDYLOMA)
- Anorectal Fissure
- Anus And Rectum Diseases
- Artificial Openings Complications
- Bladder Disorders
- Bowel Obstruction
- Carcinoma In Situ Of Digestive Organs
- Carcinoma In Situ Of The Rectum
- Chronic Constipation
- Chronic Diarrhea
- Colitis
- Colon Cancer
- Colon Polyps
- Colon Stricture
- Colonic Diverticulosis
- Colonic Polyps
- Colorectal Malignancy
- Colorectal Stricture
- Congenital Malformations Of Intestine
- Crohn's Disease
- Crohn's Disease [Regional Enteritis]
- Diverticulitis
- Enteritis
- External Hemorrhoids
- Familial Polyposis
- Female Genital Tract Fistulae
- Functional Bowel Disorder
- Functional Intestinal Disorders
- Gastrointestinal Bleeding
- Hemorrhoid Prolapse
- Hemorrhoids
- Hemorrhoids And Perianal Venous Thrombosis
- Intestinal Perforation
- Paracolostomy Hernia
- Pilonidal Cyst
- Proctal Ulcer
- Proctitis
- Pruritus
- Rectal Cancer
- Rectal Fissure
- Rectal Pain
- Rectal Ulcers
- Sigmoiditis
- Ulcerative Colitis
- Ventral Hernia
Procedures I perform
- Abdominoperineal Resection
- Anal Cancer Treatment
- Anoscopy With Biopsy
- Colectomy
- Colon Cancer Surgery
- Colon Cancer Treatment
- Colostomy
- Colostomy Revision
- Crohn's Disease Surgery
- Diverticulosis Treatment
- Endorectal Advancement Flap
- Endoscopic Mucosal Resection
- Endoscopic Submucosal Dissection
- Gastrointestinal Cancer Treatment
- Gastrointestinal Foreign Body Removal
- Gastrointestinal Perforation Repair
- Gracilis Muscle Flap
- Hemorrhoidectomy
- Ileostomy
- Inferior Mesenteric Artery Aneurysm Repair
- Irritable Bowel Syndrome Treatment
- J-Pouch Surgery
- Laparoscopic Colectomy
- Lateral Internal Sphincterotomy
- Loop Colostomy
- Low Anterior Resection
- Open Colectomy
- Ostomy Care
- Perineal Rectosigmoidectomy
- Pilonidal Abscess Treatment
- Pilonidal Cyst Treatment
- Rectal Abscess Drainage
- Rectal Cancer Surgery
- Rectal Cancer Treatment
- Rectal Foreign Body Removal
- Rectal Pain Treatment
- Rectal Resection
- Rectal Stricture Dilation
- Sigmoid Colectomy
- Small Bowel Resection
- Stoma Care
- Stoma Revision
- Thiersch Procedure
- Ulcerative Proctitis Treatment
- Volvulus Treatment
Insurance
MedStar Health accepts most major health insurance plans. If you are uncertain as to whether your individual health insurance plan is accepted at MedStar Health, please call your insurance company.
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List of insurance plans we accept
- AmeriHealth Caritas DC Healthy Families
- Choice Care Network/HUMANA (PPO)
- CareFirst MedStar PPO
- Aetna Open Choice (PPO)
- Aetna Advantage 6350PD
- Choice POS II
- Medicare Direct
- HumanaChoice Honor's plan PPO
- CIGNA Connect EPO
- Aetna Advantage 6350
- IH-Open POS Plus
- TRICARE for Life East
- CareFirst Blue Choice Opt Out Plus Open Access (POS)
- CareFirst NASCO
- Aetna Classic 5000PD
- United Healthcare Choice Plus Cardiac Global
- Kaiser Permanente HMO Plus and DHMO Plus Member
- OCI Direct (HMO)
- Uniformed Services Family Health Plan
- Jai Medical Systems - Maryland Health Choice
- Cigna TotalCare (HMO D-SNP)
- Aetna Signature Administrator PPO/TPA
- Anthem BCBS Medi Blue SNP
- Aetna Basic
- Aetna Advantage 5750
- AMERIVANTAGE/Amerigroup Community Care
- CareFirst Group Medicare Advantage
- Johns Hopkins Advantage MD PPO
- Anthem BCBS Medi Blue Plus
- NYC Medicare Advantage Plus
- CareFirst Dual Prime HMO-SNP
- Aetna Better Health of VA
- IH-EPO Plus
- CIGNA SureFit (HMO)
- Network OA
- Cigna Achieve Medicare (HMO C-SNP)
- Priority Partners - Maryland Health Choice
- Aetna Managed Choice (POS)
- Kaiser Permaenete Signature - Added Choice Cardiac Global
- Humana Gold Plus HMO
- CareFirst Blue Choice Opt Out Open Access
- UnitedHealthcare Medicare Advantage DSNP District of Columbia
- MultiPlan, Inc
- WellPoint Maryland - Maryland Health Choice
- Optima Family Care MCO - VA Medicaid MCO
- TRICARE East Prime
- Medicare Advantage - Advantra Value (PPO)
- MedStar Family Choice DC Healthcare Alliance
- Cigna True Choice Medicare (PPO)
- Geisinger Medicare Advantage
- CareFirst Group Medicare Advantage prescription drug benefit (PPO)
- Great-West Healthcare POS/CIGNA
- BCBS Out-of-State Medicare Plans (Blue Advantage)
- UnitedHealthcare Individual Exchange Plans
- Beech Street PPO
- Aetna Premier 200PD
- Anthem BCBS of VA HealthKeepers Plus
- United HealthCare Community Plan - Maryland Health Choice Program
- IH-POS
- HUMANA/Choice Care Medicare Plans (Choice, Gold Choice)
- Kaiser Permanente Select Cardiac Global
- Anthem Federal Employee Program Standard
- United Healthcare Community Plan - VA Medicaid MCO
- United Healthcare Options (PPO)
- DC/MD SHOP QHP Small Business Plans
- Kaiser Permanente Select
- IH-Open EPO Plus
- IH-Open HMO Option
- United Healthcare Choice
- Kaiser Permanente Signature - Added Choice
- Optimum Choice Preferred (POS)
- Cigna Alliance Medicare (HMO)
- Choice Fund PPO
- Kaiser Permanente Flexible Choice 3-tier POS
- Aetna Medicare Advantage PFFS Plan
- IH-Open HMO
- Magellan Complete Care of VA - VA Medicaid MCO
- CIGNA HMO & Network (HMO)
- Aetna HMO-Open Access/Select OA/HealthFund/Health Network Option OA
- Johns Hopkins Advantage MD PLUS PPO
- Aetna Elect Choice/ Open Access (POS)
- Kaiser Permanente Medicare Plus
- Tricare Reserve Select
- CareFirst Blue Card Program
- Veterans Affairs Community Care Network
- IH-POS Plus
- Aetna Better Health of MD
- Aetna Medicare Advantage HMO & PPO Plans
- Aetna Classic 5000
- Johns Hopkins Advantage MD HMO
- IH-HMO
- United Healthcare Select HMO-EPO/NPP Cardiac Global
- CareFirst EPO
- BCBS of Michigan (BCN Advantage,Security Blue, Freedom, Medicare PLUS Blue Group PPO)
- Choice POS II Open Access
- M.D. IPA Preferred (POS)
- Optimum Choice
- Blue Choice Advantage
- United Healthcare Choice Plus
- Kaiser Permanente Medicare Advantage Signature and Select
- United Healthcare Select Plus (POS)
- Choice POS
- IH-Indemnity
- Aetna VA Exchange
- UHC Group Medicare Advantage Plans (HMO, POS, PPO)
- United Healthcare Select HMO - EPO/NPP
- Anthem Federal Employee Program Basic
- Aetna Classic 3500
- Mamsi Life & Health (Indem./PPO) Cardiac Global
- Coventry Health Care of Virginia
- United Student Resources
- CIGNA PPO
- CareFirst Administrators
- CareFirst MedStar Select PPO
- IH-Network Only Plus
- POS OA
- CIGNA PPO Plus
- OA Plus
- CareFirst Federal Employee Program (Std. & Basic PPO)
- TRICARE East Select
- Medicare FFS
- UHC Passport
- Cigna Preferred Medicare (HMO)
- CareFirst BlueChoice HMO
- Healthy Blue (HMO, POS)
- Humana Medicare Advantage - PPO
- Mamsi Life & Health (Indem./PPO)
- Kaiser Maryland Medicaid MCO
- United Healthcare Choice Cardiac Global
- Aetna Elect Choice/ EPO (Aetna Health Fund)
- MedStar Family Choice - Maryland Health Choice
- MedStar Family Choice DC Healthy Families
- Core Essential (HMO)
- CareFirst Maryland Point of Service Plan
- Select HMO/HealthFund/Health Network
- CareFirst (NCA) Indemnity
- UnitedHealthcare Medicare Adv. Special Needs Plans
- Kaiser Permanente Signature
- Lasso Healthcare - Medicare Medical Savings Account
- United Healthcare Navigate Cardiac Global
- HighMark
- CareFirst FEP Blue Focus
- Anthem BCBS of VA Key Care POS/PPO/Indemnity
- IH-Open Network Only Plus
- Aetna Quality Point of Service (POS)
- Options PPO Cardiac Global
- Aetna HMO
- TriWest Healthcare Alliance
- Employee Health Plan
- CareFirst Blue Preferred PPO
- Optimum Choice & Optimum Choice Preferred (POS) Cardiac Global
- First Health PPO
- CIGNA POS/Network POS
- Fee-for-Service (FFS) District of Columbia, Maryland and Virginia Medicaid
- Cigna True Choice Plus Medicare (PPO)
- Amerigroup DC Alliance
- Erickson Advantage Plans
- Aetna Worker's Compensation Network
- Aetna Managed Choice Open Access (POS)
- Maryland Physicians Care MCO
- Anthem BCBS of VA HealthKeepers (HMO)
- Kaiser Permanente Select - Added Choice
- United Medicare Private Fee-for-Service (PFFS) plans
- CIGNA Indemnity
- IH-Open POS II
- Amerigroup DC Healthy Families
- UnitedHealthcare and AARP Medicare Complete Plans
- IH-PPO
- HealthyBlue PPO
- Advantra Platinum (PPO)
- M.D. IPA (HMO)
- Private Health Care Systems (PPO)
- AmeriHealth Caritas DC Healthcare Alliance
- Coventry of Delaware HMO/PPO
- CareFirst BlueCross BlueShield Advantage Core/Enhanced
- CareFirst Maryland Indemnity or PPO
- Coventry Health Care National Network PPO
- Health Services for Children with Special Needs
- Aetna Traditional Choice (PPO)
- Private Fee-for-Service Plans (PFFS)
- Kaiser Permanente Flexible Choice POS Cardiac Global
- Humana Medicare Advantage - HMO Open Access
- MD IPA (HMO) & MD IPA Preferred Cardiac Global
- Alterwood Advanatge HMO & DSNP Plans
- Navigate
- Police and Fire Clinic
- Sentara Health
- HumanaChoice PPO
- CareFirst Community Health Plan of MD
- Anthem BCBS Medi Blue Dual Adv
- CIGNA HMO Open Access
- CIGNA EPO
- Anthem BCBS of VA HealthKeepers (POS & POS OA)
- First Health PPO
- BlueChoice Open Access
- Aetna Student Health Insurance
Education
Board Certification: American Board of Surgery, General Surgery
Fellowship: Cleveland Clinic Florida-Weston GME (2024)
Residency: University of Toronto (2023)
Medical School: McGill University (2018)