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Dr. Christopher Allen Marshall, MD

Accepting New Patients

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Specializes in: Adult Gastroenterology
University of Massachusetts Medical School (2004)
Professional interests include: gastrointestinal problems (digestive disorders), enteroscopy
157 Union Street
Marlborough, MA 01752

Dr. Christopher Allen Marshall, MD is a gastroenterologist in Worcester, MA specializing in adult gastroenterology. He graduated from University of Massachusetts Medical School in 2004 and has 22 years of experience. Dr. Christopher Allen Marshall, MD is affiliated with UMass Memorial Medical Center and UMass Memorial Health.

View Doctor's Full Profile (508) 334-3068

Office Locations

55 Lake Avenue N
Worcester, MA 01655
open_in_new
21 Eastern Avenue
Worcester, MA 01605
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119 Belmont Street
Worcester, MA 01605
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UMass Memorial Health

157 Union Street
Marlborough, MA 01752
(508) 334-3068
(508) 334-4297
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Some issues Dr. Christopher Allen Marshall, MD can help you with:

Enteroscopy

Enteroscopy visually examines the small bowel and identifies such issues as bleeding, tumors, polyps, ulcers, and swollen lymph nodes. Common reasons this exam may be ordered are abnormal X-ray results and unexplained diarrhea.

Enteroscopies may be used alone or in combination with other procedures. For example, if a doctor suspects malignancy (cancer) in the small bowel, she may use an enteroscope to take a sample of tissue from the small bowel and have it examined in a laboratory. If there is a blockage in the small intestine that cannot be surgically removed, an enteroscopy-guided stent placement may help relieve some of the symptoms associated with the obstruction. Enteroscopes may also be used to treat intestinal bleeding and remove abnormal growths like tumors and polyps, as well as foreign objects that might have found their way into the small bowel.

There are several ways to perform an enteroscopy:

  • Push enteroscopy involves the use of a long tube with a camera, called an enteroscope. Depending on the location of the problem, the enteroscope is either passed through the mouth or rectum. This technique is often used to detect and stop bleeding in the upper small intestine.
  • Balloon enteroscopy uses scopes that have tiny balloons at the tip. The balloons inflate and deflate to help make the passage of the scope into the small bowel easier. This method is used when there is a need to access and treat certain parts of the small intestine that push enteroscopy cannot reach.
  • Capsule enteroscopy involves swallowing a capsule with a tiny camera inside it. As the capsule travels through the small intestine, the camera records and sends images that are then downloaded and analyzed by the doctor. The capsule eventually leaves the body during bowel movement. If the doctor needs to visualize the entire small intestine, capsule enteroscopy is the only option. The only drawback to this technique is that it cannot be combined with any treatment.

Enteroscopy is typically performed at the doctor's office and takes about 20 to 30 minutes, but may take longer if combined with another procedure. Patients may have a sore throat for a few hours if the scope was inserted through the mouth. Normal activities may be resumed about 24 hours following enteroscopy.

Gastrointestinal Problems (Digestive Disorders)

The gastrointestinal system, or GI tract, is the name given to a collection of organs that work together to digest food. These organs fit together in a long tube, running from the mouth to the anus, and include the esophagus, stomach, and intestines, among others. With so many parts working together, complicated by today's busy lifestyles and diets, digestive problems are common. As many as 1 in 3 Americans have a digestive or GI disorder. There are a huge variety of digestive problems, but the most common are IBS, constipation, GERD, hemorrhoids, and ulcers.

IBS, or irritable bowel syndrome, happens when the muscles surrounding the colon contract too easily or frequently. The result is abdominal pain, cramps, diarrhea or constipation, gas and bloating. IBS attacks can often be brought on by specific triggers, so a key part of treatment is learning which foods trigger IBS attacks and avoiding them. Treatment also includes exercise, avoiding stress, and medications if needed.

Constipation, or large, hard, or infrequent stools, happens to everyone at some point. It can be caused by a disruption in routine or food, or by eating a diet without many fresh fruits and vegetables. Although it is uncomfortable, constipation is common and usually not serious, but it can sometimes become chronic. Adding fiber to the diet, exercising, and taking medications may help.

GERD, or gastroesophageal reflux disease, is a severe form of chronic heartburn where stomach acid spills back up into the esophagus. Left untreated, the acid may even eat away at the esophagus and cause serious damage. Treatment includes changing the diet to avoid trigger foods, losing weight if needed, medications, or even surgery.

Hemorrhoids are blood vessels around the rectum that become irritated, swollen or torn while straining during a bowel movement. They are most often caused by constipation, but can also be caused by pregnancy, diarrhea, or simply a genetic predisposition towards hemorrhoids. Treatment involves first treating any constipation issues, then keeping the area clean and soothed until it has healed. If these measures are ineffective, surgery is sometimes used.

Peptic ulcers are sores or spots of inflammation in the lining of the stomach or close to the stomach in the small intestine. Usually this area is coated with a protective lining that shields the tissue from the strong stomach acid, but a break in the lining can let acid in, causing the sores. It used to be thought that stress caused ulcers, but now it is known that is not the case. Most often, they are caused by an infection by H. pylori bacteria, but ulcers can also be caused by alcohol abuse or overuse of aspirin, ibuprofen, naproxen, or other NSAIDS. The symptoms of an ulcer are pain, hunger, nausea, and fatigue.

Gastrointestinal problems, perhaps more than any other area, are markedly affected by lifestyle. Many disorders can be prevented or treated at least in part by eating a healthy diet high in fiber, exercising regularly, drinking enough water, and limiting alcohol intake. Still, the frequency of digestive disorders means that even the healthiest person can be affected by them. Anyone who notices blood in their stool, experiences abdominal pain, unexplained weight loss, or any significant change in bowel movements should see a doctor.

Noteworthy Medicare Patient Procedures Performed by Dr. Christopher Allen Marshall, MD in 2023

Click on any procedure below to see further details on volume and pricing among Medicare patients.

Top 25%

By Volume:

inpatient hospital care

In 2012, Dr. Christopher Allen Marshall, MD performed more inpatient hospital care (for patient admitted to hospital) procedures for Medicare patients than 75% of providers in related specialties within Massachusetts.

Medicare Procedure and Patient Information

2012 Medicare Procedure Volume

The top procedures that Dr. Christopher Allen Marshall, MD treated as a gastroenterologist in Worcester, MA during 2012 were minimally invasive procedures, gastrointestinal procedures, removal of lesion (e.g. growth) and diagnostic procedures.

Volume of procedures performed by Dr. Christopher Allen Marshall, MD for Medicare patients.

diagnostic procedures 237
doctor visit 143
gastrointestinal procedures 337
hospital care 189
injections 13
inpatient care 189
minimally invasive procedures 355
preventive care 39
removal of lesion (e.g. growth) 237

Medicare Procedure and Patient Information

2013 Medicare Procedure Volume

The top procedures that Dr. Christopher Allen Marshall, MD treated as a gastroenterologist in Worcester, MA during 2013 were minimally invasive procedures, gastrointestinal procedures, removal of lesion (e.g. growth) and diagnostic procedures.

Volume of procedures performed by Dr. Christopher Allen Marshall, MD for Medicare patients.

diagnostic procedures 220
doctor visit 53
gastrointestinal procedures 302
hospital care 140
injections 12
inpatient care 140
minimally invasive procedures 315
preventive care 43
removal of lesion (e.g. growth) 220

2013 Medicare Patient Data

Information about Medicare patients treated by Dr. Christopher Allen Marshall, MD.

Gender
Male 203
Female 210
Ethnicity
Non-Hispanic White 358
Black 13
Hispanic 31
Asian 0
Other 0
Native American 0
Age
From 65 to 74 152
From 75 to 84 82
85 and over 48
Less than 65 131

Conditions of Medicare patients treated by Dr. Christopher Allen Marshall, MD in 2013

Hypertension 71
High Cholesterol 53
Stroke 9
Ischemic Heart Disease 42
Depression 40
Chronic Kidney Disease 31
Asthma 18
Osteoperosis 8
Atrial Fibrilation 15
Heart Failure 25
Chronic Obstructive Pulmonary Disease 25
Diabetes 34
Dementia 13
Cancer 13

Medicare Procedure and Patient Information

2014 Medicare Procedure Volume

The top procedures that Dr. Christopher Allen Marshall, MD treated as a gastroenterologist in Worcester, MA during 2014 were minimally invasive procedures, gastrointestinal procedures, removal of lesion (e.g. growth) and diagnostic procedures.

Volume of procedures performed by Dr. Christopher Allen Marshall, MD for Medicare patients.

anastomosis 16
catheterization 16
diagnostic procedures 244
doctor visit 118
gastrointestinal procedures 357
hospital care 149
injections 12
inpatient care 149
minimally invasive procedures 380
preventive care 46
removal of lesion (e.g. growth) 244

2014 Medicare Patient Data

Information about Medicare patients treated by Dr. Christopher Allen Marshall, MD.

Gender
Male 220
Female 259
Ethnicity
Non-Hispanic White 416
Black 15
Hispanic 35
Asian 0
Other 0
Native American 0
Age
From 65 to 74 188
From 75 to 84 104
85 and over 52
Less than 65 135

Conditions of Medicare patients treated by Dr. Christopher Allen Marshall, MD in 2014

Hypertension 71
High Cholesterol 56
Stroke 5
Ischemic Heart Disease 43
Depression 39
Chronic Kidney Disease 35
Asthma 15
Osteoperosis 10
Atrial Fibrilation 18
Heart Failure 24
Chronic Obstructive Pulmonary Disease 20
Diabetes 37
Dementia 14
Cancer 13

Medicare Procedure and Patient Information

2015 Medicare Procedure Volume

The top procedures that Dr. Christopher Allen Marshall, MD treated as a gastroenterologist in Worcester, MA during 2015 were minimally invasive procedures, gastrointestinal procedures, removal of lesion (e.g. growth) and diagnostic procedures.

Volume of procedures performed by Dr. Christopher Allen Marshall, MD for Medicare patients.

diagnostic procedures 256
doctor visit 149
gastrointestinal procedures 369
hospital care 174
inpatient care 174
minimally invasive procedures 399
preventive care 70
removal of lesion (e.g. growth) 256

2015 Medicare Patient Data

Information about Medicare patients treated by Dr. Christopher Allen Marshall, MD.

Gender
Male 466
Female 582
Ethnicity
Non-Hispanic White 912
Black 26
Hispanic 80
Asian 0
Other 0
Native American 0
Age
From 65 to 74 396
From 75 to 84 242
85 and over 130
Less than 65 280

Conditions of Medicare patients treated by Dr. Christopher Allen Marshall, MD in 2015

Hypertension 69
High Cholesterol 56
Stroke 6
Ischemic Heart Disease 42
Depression 37
Chronic Kidney Disease 38
Asthma 18
Osteoperosis 8
Atrial Fibrilation 14
Heart Failure 24
Chronic Obstructive Pulmonary Disease 20
Diabetes 35
Dementia 13
Cancer 13

Medicare Procedure and Patient Information

2016 Medicare Procedure Volume

The top procedures that Dr. Christopher Allen Marshall, MD treated as a gastroenterologist in Worcester, MA during 2016 were minimally invasive procedures, gastrointestinal procedures, removal of lesion (e.g. growth) and diagnostic procedures.

Volume of procedures performed by Dr. Christopher Allen Marshall, MD for Medicare patients.

diagnostic procedures 283
doctor visit 160
gastrointestinal procedures 319
hospital care 140
inpatient care 140
minimally invasive procedures 342
preventive care 16
removal of lesion (e.g. growth) 283

2016 Medicare Patient Data

Information about Medicare patients treated by Dr. Christopher Allen Marshall, MD.

Gender
Male 211
Female 263
Ethnicity
Non-Hispanic White 406
Black 16
Hispanic 34
Asian 0
Other 0
Native American 0
Age
From 65 to 74 184
From 75 to 84 99
85 and over 60
Less than 65 131

Conditions of Medicare patients treated by Dr. Christopher Allen Marshall, MD in 2016

Hypertension 64
High Cholesterol 53
Stroke 5
Ischemic Heart Disease 39
Depression 36
Chronic Kidney Disease 39
Asthma 23
Osteoperosis 8
Atrial Fibrilation 15
Heart Failure 22
Chronic Obstructive Pulmonary Disease 18
Diabetes 33
Dementia 13
Cancer 11

Medicare Procedure and Patient Information

2017 Medicare Procedure Volume

The top procedures that Dr. Christopher Allen Marshall, MD treated as a gastroenterologist in Worcester, MA during 2017 were minimally invasive procedures, gastrointestinal procedures, removal of lesion (e.g. growth) and diagnostic procedures.

Volume of procedures performed by Dr. Christopher Allen Marshall, MD for Medicare patients.

diagnostic procedures 293
doctor visit 132
gastrointestinal procedures 375
hospital care 89
inpatient care 89
minimally invasive procedures 407
preventive care 15
removal of lesion (e.g. growth) 293
stent placement (stenting) 16

2017 Medicare Patient Data

Information about Medicare patients treated by Dr. Christopher Allen Marshall, MD.

Gender
Male 242
Female 243
Ethnicity
Non-Hispanic White 419
Black 0
Hispanic 35
Asian 0
Other 17
Native American 0
Age
From 65 to 74 214
From 75 to 84 109
85 and over 49
Less than 65 113

Conditions of Medicare patients treated by Dr. Christopher Allen Marshall, MD in 2017

Hypertension 68
High Cholesterol 51
Stroke 6
Ischemic Heart Disease 40
Depression 35
Chronic Kidney Disease 36
Asthma 10
Osteoperosis 8
Atrial Fibrilation 15
Heart Failure 21
Chronic Obstructive Pulmonary Disease 17
Diabetes 28
Dementia 14
Cancer 12

Medicare Procedure and Patient Information

2018 Medicare Procedure Volume

The top procedures that Dr. Christopher Allen Marshall, MD treated as a gastroenterologist in Worcester, MA during 2018 were minimally invasive procedures, gastrointestinal procedures, removal of lesion (e.g. growth) and diagnostic procedures.

Volume of procedures performed by Dr. Christopher Allen Marshall, MD for Medicare patients.

diagnostic procedures 331
doctor visit 200
gastrointestinal procedures 412
hospital care 103
inpatient care 103
minimally invasive procedures 461
preventive care 45
removal of lesion (e.g. growth) 331

2018 Medicare Patient Data

Information about Medicare patients treated by Dr. Christopher Allen Marshall, MD.

Gender
Male 232
Female 284
Ethnicity
Non-Hispanic White 459
Black 0
Hispanic 29
Asian 0
Other 13
Native American 0
Age
From 65 to 74 222
From 75 to 84 134
85 and over 43
Less than 65 117

Conditions of Medicare patients treated by Dr. Christopher Allen Marshall, MD in 2018

Hypertension 70
High Cholesterol 58
Stroke 5
Ischemic Heart Disease 42
Depression 34
Chronic Kidney Disease 40
Asthma 9
Osteoperosis 11
Atrial Fibrilation 14
Heart Failure 23
Chronic Obstructive Pulmonary Disease 18
Diabetes 32
Dementia 14
Cancer 12

Medicare Procedure and Patient Information

2019 Medicare Procedure Volume

The top procedures that Dr. Christopher Allen Marshall, MD treated as a gastroenterologist in Worcester, MA during 2019 were minimally invasive procedures, gastrointestinal procedures, removal of lesion (e.g. growth) and diagnostic procedures.

Volume of procedures performed by Dr. Christopher Allen Marshall, MD for Medicare patients.

diagnostic procedures 374
doctor visit 168
gastrointestinal procedures 466
hospital care 131
inpatient care 131
minimally invasive procedures 524
preventive care 48
removal of lesion (e.g. growth) 374

2019 Medicare Patient Data

Information about Medicare patients treated by Dr. Christopher Allen Marshall, MD.

Gender
Male 283
Female 340
Ethnicity
Non-Hispanic White 537
Black 0
Hispanic 36
Asian 0
Other 24
Native American 0
Age
From 65 to 74 295
From 75 to 84 143
85 and over 54
Less than 65 131

Conditions of Medicare patients treated by Dr. Christopher Allen Marshall, MD in 2019

Hypertension 67
High Cholesterol 55
Stroke 5
Ischemic Heart Disease 38
Depression 36
Chronic Kidney Disease 37
Asthma 11
Osteoperosis 9
Atrial Fibrilation 13
Heart Failure 20
Chronic Obstructive Pulmonary Disease 20
Diabetes 28
Dementia 13
Cancer 12

Medicare Procedure and Patient Information

2020 Medicare Procedure Volume

The top procedures that Dr. Christopher Allen Marshall, MD treated as a gastroenterologist in Worcester, MA during 2020 were minimally invasive procedures, gastrointestinal procedures, removal of lesion (e.g. growth) and diagnostic procedures.

Volume of procedures performed by Dr. Christopher Allen Marshall, MD for Medicare patients.

diagnostic procedures 196
doctor visit 88
gastrointestinal procedures 255
hospital care 155
inpatient care 155
minimally invasive procedures 312
preventive care 36
removal of lesion (e.g. growth) 196

2020 Medicare Patient Data

Information about Medicare patients treated by Dr. Christopher Allen Marshall, MD.

Gender
Male 238
Female 231
Ethnicity
Non-Hispanic White 401
Black 0
Hispanic 37
Asian 0
Other 20
Native American 0
Age
From 65 to 74 212
From 75 to 84 112
85 and over 45
Less than 65 100

Conditions of Medicare patients treated by Dr. Christopher Allen Marshall, MD in 2020

Hypertension 67
High Cholesterol 59
Stroke 7
Ischemic Heart Disease 41
Depression 37
Chronic Kidney Disease 43
Asthma 10
Osteoperosis 11
Atrial Fibrilation 15
Heart Failure 28
Chronic Obstructive Pulmonary Disease 19
Diabetes 34
Dementia 14
Cancer 13

Medicare Procedure and Patient Information

2021 Medicare Procedure Volume

The top procedures that Dr. Christopher Allen Marshall, MD treated as a gastroenterologist in Worcester, MA during 2021 were minimally invasive procedures, gastrointestinal procedures, removal of lesion (e.g. growth) and diagnostic procedures.

Volume of procedures performed by Dr. Christopher Allen Marshall, MD for Medicare patients.

diagnostic procedures 254
doctor visit 121
gastrointestinal procedures 317
hospital care 194
inpatient care 194
minimally invasive procedures 387
preventive care 41
removal of lesion (e.g. growth) 254

2021 Medicare Patient Data

Information about Medicare patients treated by Dr. Christopher Allen Marshall, MD.

Gender
Male 264
Female 305
Ethnicity
Non-Hispanic White 509
Black 0
Hispanic 30
Asian 0
Other 18
Native American 0
Age
From 65 to 74 263
From 75 to 84 152
85 and over 49
Less than 65 105

Conditions of Medicare patients treated by Dr. Christopher Allen Marshall, MD in 2021

Hypertension 71
High Cholesterol 64
Stroke 8
Ischemic Heart Disease 41
Depression 35
Chronic Kidney Disease 46
Asthma 10
Osteoperosis 11
Atrial Fibrilation 16
Heart Failure 28
Chronic Obstructive Pulmonary Disease 20
Diabetes 33
Dementia 16
Cancer 14

Medicare Procedure and Patient Information

2022 Medicare Procedure Volume

The top procedures that Dr. Christopher Allen Marshall, MD treated as a gastroenterologist in Worcester, MA during 2022 were minimally invasive procedures, gastrointestinal procedures, removal of lesion (e.g. growth) and diagnostic procedures.

Volume of procedures performed by Dr. Christopher Allen Marshall, MD for Medicare patients.

diagnostic procedures 254
doctor visit 125
gastrointestinal procedures 296
hospital care 164
inpatient care 164
minimally invasive procedures 364
preventive care 29
removal of lesion (e.g. growth) 254

2022 Medicare Patient Data

Information about Medicare patients treated by Dr. Christopher Allen Marshall, MD.

Gender
Male 265
Female 274
Ethnicity
Non-Hispanic White 480
Black 0
Hispanic 28
Asian 0
Other 17
Native American 0
Age
From 65 to 74 236
From 75 to 84 167
85 and over 50
Less than 65 86

Conditions of Medicare patients treated by Dr. Christopher Allen Marshall, MD in 2022

Hypertension 75
High Cholesterol 75
Stroke 10
Ischemic Heart Disease 34
Depression 36
Chronic Kidney Disease 37
Asthma 13
Osteoperosis 15
Atrial Fibrilation 26
Heart Failure 27
Chronic Obstructive Pulmonary Disease 27
Diabetes 34
Dementia 13
Cancer 17

Medicare Procedure and Patient Information

Average Medicare Procedure Volume From 2012 - 2022

Volume of procedures performed by Dr. Christopher Allen Marshall, MD for Medicare patients.

The highest averages for the top procedures that Dr. Christopher Allen Marshall, MD treated as a gastroenterologist in Worcester, MA were minimally invasive procedures, gastrointestinal procedures, removal of lesion (e.g. growth) and diagnostic procedures.

anastomosis 16
catheterization 16
diagnostic procedures 267
doctor visit 132
gastrointestinal procedures 345
hospital care 148
injections 12
inpatient care 148
minimally invasive procedures 386
preventive care 38
removal of lesion (e.g. growth) 267
stent placement (stenting) 16

Average Medicare Patient Data From 2012 - 2022

Information about Medicare patients treated by Dr. Christopher Allen Marshall, MD.

Gender
Male 238
Female 271
Ethnicity
Black / African American 6
Asian / Pacific Islander 0
Non-Hispanic White 445
Native American / Alaskan Native 0
Hispanic 34
Other 9
Age
75 to 84 122
85 and over 52
Less than 65 120
65 to 74 214

Average of Total of Conditions of Medicare patients treated by Dr. Christopher Allen Marshall, MD From 2012 - 2022

The highest averages of the most common conditions of Medicare patients that Dr. Christopher Allen Marshall, MD treated were hypertension, high cholesterol, ischemic heart disease and chronic kidney disease.

Hypertension 63
High Cholesterol 52
Stroke 6
Ischemic Heart Disease 36
Depression 33
Chronic Kidney Disease 34
Asthma 12
Osteoporosis 9
Heart Failure 22
Chronic Obstructive Pulmonary Disease 18
Diabetes 29
Atrial Fibrillation 14
Dementia 12
Cancer 11

Education & Training

Dr. Christopher Allen Marshall, MD graduated from University of Massachusetts Medical School in 2004. He completed residency at UMass Memorial Medical Center. He is certified by the American Board of Internal Medicine: Gastroenterology and has a state license in Massachusetts.

Medical School: University of Massachusetts Medical School (2004)

Residency: UMass Memorial Medical Center

Board Certification: American Board of Internal Medicine: Gastroenterology

Licensed In: Massachusetts

Affiliations & Hospitals

Dr. Christopher Allen Marshall, MD is associated with these hospitals and organizations:

UMass Memorial Medical Center
UMass Memorial Health

Ratings & Reviews

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General Payments

These charts describe general payments received by Dr. Christopher Allen Marshall, MD. Doctors may receive payments for a number of reasons, including meal compensation, travel compensation, and consulting.

Payments by Company
Covidien LP $6,631 GI Solutions
$3,318 		PillCam
$3,312
Olympus Corporation $3,605
$3,605
Olympus America Inc. $1,873 EndoClot SIS
$1,823 		Olympus EMR & ESD Devices
$50
Boston Scientific Corporation $1,048 EXALT Model D
$415 		GENERAL THERAPIES
$132 		EXALT BX 2
$110 		SPYGLASS
$102 		METAL STENTS - G.I.
$74 		Other
$215
E.R. Squibb & Sons, L.L.C. $300
$300
Other $1,237 FUJIFILM
$295 		XIFAXAN 550 MG TABLETS
$122 		Erbe VIO
$97 		ERBE VIO3
$97 		STELARA
$76 		Other
$550
Types of Payments
Compensation for services other than consulting, including serving as faculty or as a speaker at a venue other than a continuing education program $7,530
Consulting Fee $4,678
Food and Beverage $2,403
Education $62
Travel and Lodging $20

Research Payments

Dr. Christopher Allen Marshall, MD has received 36 research payments totaling $107,116.

Biography

Dr. Christopher Marshall is an adult gastroenterology specialist. He is a graduate of the University of Massachusetts Medical School and a graduate of UMass Memorial Medical Center's residency program. His clinical interests include gastrointestinal problems (digestive disorders) and enteroscopy. Dr. Marshall is affiliated with UMass Memorial Medical Center. According to Doctor.com, he is currently accepting new patients at his office in Worcester, MA.

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