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
- Choice POS
- Kaiser Maryland Medicaid MCO
- Healthy Blue (HMO, POS)
- Cigna Alliance Medicare (HMO)
- Aetna VA Exchange
- United Healthcare Choice Plus Cardiac Global
- Aetna Student Health Insurance
- Coventry Health Care National Network PPO
- United Healthcare Community Plan - VA Medicaid MCO
- Tricare Reserve Select
- Amerigroup DC Healthy Families
- Police and Fire Clinic
- United Healthcare Select Plus (POS)
- Aetna Elect Choice/ EPO (Aetna Health Fund)
- Advantra Platinum (PPO)
- Maryland Physicians Care MCO
- TRICARE East Prime
- Aetna Classic 5000PD
- IH-Network Only Plus
- CIGNA EPO
- Aetna Advantage 6350PD
- Humana Gold Plus HMO
- TRICARE for Life East
- Anthem Federal Employee Program Standard
- IH-Open EPO Plus
- Optima Family Care MCO - VA Medicaid MCO
- UHC Group Medicare Advantage Plans (HMO, POS, PPO)
- Aetna HMO-Open Access/Select OA/HealthFund/Health Network Option OA
- AmeriHealth Caritas DC Healthy Families
- Lasso Healthcare - Medicare Medical Savings Account
- CareFirst BlueChoice HMO
- UnitedHealthcare and AARP Medicare Complete Plans
- CareFirst NASCO
- CIGNA Indemnity
- BCBS of Michigan (BCN Advantage,Security Blue, Freedom, Medicare PLUS Blue Group PPO)
- AMERIVANTAGE/Amerigroup Community Care
- Optimum Choice
- CareFirst Administrators
- Cigna Achieve Medicare (HMO C-SNP)
- CIGNA HMO Open Access
- Navigate
- Aetna Premier 200PD
- Kaiser Permanente Signature - Added Choice
- HighMark
- CIGNA SureFit (HMO)
- Core Essential (HMO)
- Cigna True Choice Plus Medicare (PPO)
- Aetna Advantage 6350
- Coventry of Delaware HMO/PPO
- Alterwood Advanatge HMO & DSNP Plans
- Aetna HMO
- Cigna TotalCare (HMO D-SNP)
- BlueChoice Open Access
- HumanaChoice Honor's plan PPO
- Johns Hopkins Advantage MD HMO
- MedStar Family Choice DC Healthcare Alliance
- IH-HMO
- Cigna True Choice Medicare (PPO)
- IH-POS Plus
- Kaiser Permanente Flexible Choice 3-tier POS
- United HealthCare Community Plan - Maryland Health Choice Program
- Aetna Classic 3500
- Priority Partners - Maryland Health Choice
- Medicare FFS
- Humana Medicare Advantage - HMO Open Access
- HealthyBlue PPO
- CIGNA POS/Network POS
- Select HMO/HealthFund/Health Network
- CareFirst MedStar Select PPO
- Optimum Choice & Optimum Choice Preferred (POS) Cardiac Global
- United Healthcare Choice Cardiac Global
- Aetna Medicare Advantage PFFS Plan
- Johns Hopkins Advantage MD PPO
- Magellan Complete Care of VA - VA Medicaid MCO
- Aetna Open Choice (PPO)
- UnitedHealthcare Medicare Adv. Special Needs Plans
- Aetna Traditional Choice (PPO)
- IH-EPO Plus
- HUMANA/Choice Care Medicare Plans (Choice, Gold Choice)
- United Healthcare Select HMO - EPO/NPP
- Beech Street PPO
- OA Plus
- Mamsi Life & Health (Indem./PPO)
- Anthem BCBS Medi Blue SNP
- AmeriHealth Caritas DC Healthcare Alliance
- Kaiser Permanente Medicare Advantage Signature and Select
- MedStar Family Choice - Maryland Health Choice
- Anthem BCBS Medi Blue Plus
- DC/MD SHOP QHP Small Business Plans
- Kaiser Permanente Select
- Aetna Classic 5000
- Aetna Basic
- Kaiser Permanente Medicare Plus
- Aetna Advantage 5750
- Medicare Advantage - Advantra Value (PPO)
- Anthem BCBS of VA HealthKeepers (HMO)
- Anthem BCBS Medi Blue Dual Adv
- Kaiser Permaenete Signature - Added Choice Cardiac Global
- IH-PPO
- Veterans Affairs Community Care Network
- CareFirst (NCA) Indemnity
- CareFirst Group Medicare Advantage prescription drug benefit (PPO)
- WellPoint Maryland - Maryland Health Choice
- United Healthcare Select HMO-EPO/NPP Cardiac Global
- HumanaChoice PPO
- IH-Open Network Only Plus
- Jai Medical Systems - Maryland Health Choice
- Aetna Elect Choice/ Open Access (POS)
- United Healthcare Choice Plus
- TriWest Healthcare Alliance
- Humana Medicare Advantage - PPO
- Erickson Advantage Plans
- United Healthcare Choice
- Choice Care Network/HUMANA (PPO)
- Fee-for-Service (FFS) District of Columbia, Maryland and Virginia Medicaid
- M.D. IPA (HMO)
- First Health PPO
- Kaiser Permanente Flexible Choice POS Cardiac Global
- IH-Indemnity
- Coventry Health Care of Virginia
- Kaiser Permanente Select - Added Choice
- Kaiser Permanente Select Cardiac Global
- TRICARE East Select
- Private Health Care Systems (PPO)
- Anthem BCBS of VA HealthKeepers Plus
- Choice Fund PPO
- Blue Choice Advantage
- CIGNA PPO Plus
- CareFirst Dual Prime HMO-SNP
- Health Services for Children with Special Needs
- IH-Open POS Plus
- Anthem BCBS of VA Key Care POS/PPO/Indemnity
- Kaiser Permanente Signature
- United Student Resources
- Aetna Better Health of VA
- CIGNA Connect EPO
- M.D. IPA Preferred (POS)
- Employee Health Plan
- CareFirst Group Medicare Advantage
- CareFirst FEP Blue Focus
- OCI Direct (HMO)
- CareFirst Blue Card Program
- CareFirst Blue Preferred PPO
- Anthem Federal Employee Program Basic
- CareFirst Federal Employee Program (Std. & Basic PPO)
- UnitedHealthcare Individual Exchange Plans
- UnitedHealthcare Medicare Advantage DSNP District of Columbia
- CareFirst Maryland Point of Service Plan
- CIGNA PPO
- CareFirst BlueCross BlueShield Advantage Core/Enhanced
- MultiPlan, Inc
- Great-West Healthcare POS/CIGNA
- First Health PPO
- Medicare Direct
- CareFirst MedStar PPO
- Sentara Health
- Aetna Managed Choice Open Access (POS)
- Cigna Preferred Medicare (HMO)
- MedStar Family Choice DC Healthy Families
- Amerigroup DC Alliance
- Aetna Signature Administrator PPO/TPA
- Private Fee-for-Service Plans (PFFS)
- United Healthcare Options (PPO)
- Geisinger Medicare Advantage
- CareFirst EPO
- MD IPA (HMO) & MD IPA Preferred Cardiac Global
- Network OA
- CareFirst Blue Choice Opt Out Plus Open Access (POS)
- POS OA
- United Medicare Private Fee-for-Service (PFFS) plans
- CareFirst Community Health Plan of MD
- Options PPO Cardiac Global
- IH-Open HMO
- UHC Passport
- Choice POS II
- Choice POS II Open Access
- Aetna Managed Choice (POS)
- Mamsi Life & Health (Indem./PPO) Cardiac Global
- United Healthcare Navigate Cardiac Global
- IH-POS
- IH-Open POS II
- Optimum Choice Preferred (POS)
- Aetna Better Health of MD
- Aetna Medicare Advantage HMO & PPO Plans
- IH-Open HMO Option
- NYC Medicare Advantage Plus
- Aetna Quality Point of Service (POS)
- Aetna Worker's Compensation Network
- Johns Hopkins Advantage MD PLUS PPO
- CareFirst Blue Choice Opt Out Open Access
- CareFirst Maryland Indemnity or PPO
- Uniformed Services Family Health Plan
- Kaiser Permanente HMO Plus and DHMO Plus Member
- Anthem BCBS of VA HealthKeepers (POS & POS OA)
- CIGNA HMO & Network (HMO)
- BCBS Out-of-State Medicare Plans (Blue Advantage)
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)