JM
30 Years of Experience
Accepting patients
Affiliated with a Castle Connolly Top Hospital
Who is Dr. Marks, Colon & Rectal Surgeon (Proctologist) in Bryn Mawr, PA?
Dr. John Marks, MD is a Colon & Rectal Surgeon (Proctologist), who primarily practices in Bryn Mawr, PA with 2 additional practice locations. He has been practicing for over 30 years and is board certified by the American Board of Colon & Rectal Surgery and American Board of Surgery. Dr. Marks graduated from Sidney Kimmel Medical College at Thomas Jefferson University and completed his residency at Thos Jefferson Univ Hosp, Colon And Rectal Surgery; Thos Jefferson Univ Hosp, General Surgery. Dr. Marks is fluent in English and French, and is currently seeing new patients. Dr. Marks’s practice accepts Cigna, Medicare, UnitedHealthcare and other major insurance plans. To book an appointment or to confirm insurance options, please call Dr. Marks’s office.
What are Areas of Expertise for Dr. Marks?
Dr. John Marks, MD is a highly-rated, board-certified Colon & Rectal Surgeon (Proctologist) known for expertly diagnosing, treating, and managing a wide array of related conditions or procedures. Utilizing the latest medical advancements and evidence-based practices, Dr. Marks empowers patients to confidently navigate their health journey, specializing in Colon & Rectal Cancer & Surgery, Diverticulitis, Rectal Cancer/Sphincter Preservation, Robotic Surgery, or comprehensive wellness support. Serving the Bryn Mawr/PA community, Dr. Marks is dedicated to enhancing lives through expert, patient-centered care.
Where did Dr. Marks go to medical school and complete their residency?
Residency: Thos Jefferson Univ Hosp, Colon And Rectal Surgery; Thos Jefferson Univ Hosp, General Surgery | Thomas Jefferson University Hospital Program
Medical School: Jefferson Medical College of Thomas Jefferson University | Sidney Kimmel Medical College at Thomas Jefferson University
Is Dr. Marks board certified in Colon & Rectal Surgeon (Proctologist)?
Yes, Dr. John Marks, MD is board certified by the American Board of Colon & Rectal Surgery , American Board of Surgery
What languages does Dr. Marks speak?
Dr. Marks and their clinical team can communicate with patients in the following languages:
English
French
What conditions does Dr. Marks treat?
As a Colon & Rectal Surgeon (Proctologist), Dr. Marks diagnoses, treats, and manages a wide range of conditions. This condition information is derived from anonymized insurance claims and highlights the medical conditions most commonly treated by Dr. Marks. It provides insight into the doctor’s areas of experience and expertise based on real-world patient encounters from the past two years, updated quarterly.
Also known as:
- Colorectal Cancer
- Rectal cancer
- Colon cancer
- Bowel cancer
- Malignant neoplasm of rectum
- Malignant neoplasm of sigmoid colon
- Malignant neoplasm of colon
ICD-10 Codes:
- C20: Malignant neoplasm of rectum
- C187: Malignant neoplasm of sigmoid colon
- C189: Malignant neoplasm of colon, unspecified
Also known as:
- Colon Cancer Screening
- Health Screening
- Colorectal Cancer Screening (PDQ®)
- Screening Tests to Detect Colorectal Cancer and Polyps
- Tests to Detect Colorectal Cancer and Polyps
- Colorectal Cancer Screening
- Colonoscopy Screening
- Bowel Cancer Screening
ICD-10 Codes:
- Z1211: Encounter for screening for malignant neoplasm of colon
Also known as:
- Overweight
- Healthy Weight
- Body Weight
- High Body Mass Index
- Excess Weight
- Weight Management Issues
- Normal Weight
- Body Mass Index
- Optimal Weight
ICD-10 Codes:
- Z6825: Body mass index [BMI] 25.0-25.9, adult
- Z6826: Body mass index [BMI] 26.0-26.9, adult
- Z6827: Body mass index [BMI] 27.0-27.9, adult
- Z6824: Body mass index [BMI] 24.0-24.9, adult
Also known as:
- Intestine Diverticulitis
- Large Intestine Diverticulitis
- Diverticulosis and Diverticulitis
- Inflamed Bowel Diverticula
- Bowel Diverticular Inflammation
- Inflamed Colon Diverticula
- Colon Diverticular Inflammation
ICD-10 Codes:
- K5792: Diverticulitis of intestine, part unspecified, without perforation or abscess without bleeding
- K5732: Diverticulitis of large intestine without perforation or abscess without bleeding
Also known as:
- Colostomy Care
- Ileostomy Care
- Ostomy
- Stoma Care
- Bowel Diversion Care
- Ostomy Bag Management
- Ileostomy Management
- Small Intestine Stoma Care
- Ileostomy Follow-up
ICD-10 Codes:
- Z433: Encounter for attention to colostomy
- Z432: Encounter for attention to ileostomy
Also known as:
- Adult BMI 23.0-23.9
- Adult BMI 28.0-28.9
- Body Weight
- BMI in healthy range
- Normal adult BMI
- Healthy weight BMI
- Overweight BMI
- Adult pre-obesity BMI
- Higher than normal BMI
ICD-10 Codes:
- Z6823: Body mass index [BMI] 23.0-23.9, adult
- Z6828: Body mass index [BMI] 28.0-28.9, adult
Also known as:
- Large Intestine Diverticulosis
- Diverticulosis and Diverticulitis
- Diverticular Disease
- Colon Diverticula
- Pockets in the Colon
ICD-10 Codes:
- K5730: Diverticulosis of large intestine without perforation or abscess without bleeding
Also known as:
- Hemorrhoids
- Piles
- Swollen Veins in Anus
- Anal Lumps
ICD-10 Codes:
- K649: Unspecified hemorrhoids
Also known as:
- Other Pre-Procedure Examination
- Various pre-op checks
- Miscellaneous pre-surgery exams
- Other pre-treatment assessments
ICD-10 Codes:
- Z01818: Encounter for other preprocedural examination
Also known as:
- Other Anal and Rectal Condition
- Anal Disorder
- Rectal Disorder
- Proctitis
- Anal Disorders
- Rectal Disorders
ICD-10 Codes:
- K6289: Other specified diseases of anus and rectum
Also known as:
- Low Body Mass Index (BMI)
- Body Weight
- Underweight BMI
- Low BMI in adults
- BMI below 19.9
ICD-10 Codes:
- Z681: Body mass index [BMI] 19.9 or less, adult
Also known as:
- Anal Cancer
- Anal Cancer Treatment (PDQ®)
- Anus Cancer
- Anal Carcinoma
ICD-10 Codes:
- C210: Malignant neoplasm of anus, unspecified
Which procedures does Dr. Marks perform as a Colon & Rectal Surgeon (Proctologist)?
As a Colon & Rectal Surgeon (Proctologist), procedures performed by a Dr. John Marks may include:
- Abdominal Colorectal Surgery
- Anal Pap Smear
- Anoscopy
- Colon Cancer Screening
- Colorectal Surgeon Consultation
- Colorectal Surgeon Follow Up
- Colorectal Surgery
- Colorectal Surgery Second Opinion
For detailed information, please contact Dr. Marks' office.
Does Dr. Marks accept my insurance?
Dr. Marks accepts most major insurance plans. Important: Please call our office at before your appointment to verify that your specific plan and network are accepted.
What insurance plans does Dr. Marks accept in Bryn Mawr, PA?
Dr. Marks in Bryn Mawr, PA accepts plans from many carriers. While this list is updated regularly, it is not a guarantee of coverage.
Top Insurances
All Other Third Party
BCBS Unspecified
Cigna
CVS Health (formerly Aetna)
Highmark Inc.
Humana
Independence Blue Cross
Independent Health
Medicare
UnitedHealthcare
View All Insurances
Where is Dr. Marks' office located?
Recognitions
Castle Connolly Doctor’s Choice Awards
Doctor’s Choice - All Time
Among the most nominated for the Castle Connolly Top Doctor recognition across all time
Doctor’s Choice - 2025
Among the most nominated for the Castle Connolly Top Doctor recognition in 2025
What is Dr. Marks's NPI number?An National Provider Identifier (NPI) is a unique ID number that identifies doctors and healthcare providers nationwide.
Dr. Marks's National Provider Identifier (NPI) number is 1346212594.
What common questions do patients ask about Dr. Marks?
Here are answers to patients Frequently Asked Questions (FAQ’s) about Dr. Marks
What is Dr. John Marks's specialty?
Dr. Marks is a Colon & Rectal Surgeon (Proctologist) near Bryn Mawr, PA. A colon and rectal surgeon possesses the expertise to diagnose and treat a variety of ailments affecting the intestinal tract, including the colon, rectum, anal canal, and perianal area, through both medical and surgical interventions. Furthermore, this professional also engages with other organs and tissues, including the liver, urinary system, and female reproductive system, that are relevant to primary intestinal disorders. Contact Dr. Marks to book an appointment today.
Is this Dr. John Marks affiliated with a ranked Castle Connolly Top Hospital?
Yes, Dr. Marks is affiliated with Lankenau Medical Center which is a Castle Connolly Top Hospital. Castle Connolly Top Hospitals are healthcare institutions recognized for their excellence in specific medical procedures and overall patient care. They are identified through a rigorous peer nomination process, evaluating factors like patient outcomes, quality of care, and expertise. The list recognizes hospitals that excel in 20 or more specific medical procedures, representing the top 25% nationwide. Castle Connolly Top Hospitals
Where can I learn more about Colon & Rectal Surgeon (Proctologist)?
Explore Colon & Rectal Surgeon (Proctologist) with insights from trusted medical experts on EverydayHealth.com, where you'll find the most relevant content and helpful condition guides for up-to date information about symptoms, causes, diagnosis, treatment and more. See all our health guides to find trusted information on medical conditions from our experts at Everyday Health.
Is John Marks accepting new patients in Bryn Mawr, PA?
Yes, Dr. John Marks is accepting new patients at this time.
Does Dr. John Marks offer online booking?
Please contact Dr. Marks's office for information about online booking, telehealth, or to schedule an appointment.
How can I make an appointment with John Marks?
Please contact Dr. Marks's office for information regarding telehealth appointment availability or for scheduling assistance.
Which board certifications does Dr. John Marks have?
Dr. John Marks is certified by the American Board of Colon & Rectal Surgery and American Board of Surgery.
Other Colon & Rectal Surgeon (Proctologist) Near Bryn Mawr, PA
PP
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Accepting patientsDr. Philip Pearson, MD is a Surgeon, who primarily practices in Bryn Mawr, PA with 1 additional practice location. He is board certified by the American Board of Surgery.
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Accepting patientsDr. Robert Noone, MD is a Colon & Rectal Surgeon (Proctologist), who primarily practices in Bryn Mawr, PA with 1 additional practice location. He is board certified by the American Board of Surgery.
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HS
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Accepting patientsDr. Henry Schoonyoung, MD is a Colon & Rectal Surgeon (Proctologist), who primarily practices in Bryn Mawr, PA with 2 additional practice locations. He is board certified.
Bryn Mawr, PA