Testing Immunotherapy (Atezolizumab) With or Without Chemotherapy in Locoregional MSI-H/dMMR Gastric and Gastroesophageal Junction (GEJ) Cancer

Mount Sinai West, New York

Mount Sinai Hospital, New York

Helen F Graham Cancer Center, Newark

Medical Oncology Hematology Consultants PA, Newark

Beebe South Coastal Health Campus, Millville

Beebe Health Campus, Rehoboth Beach

VCU Massey Cancer Center at Stony Point, Richmond

VCU Massey Comprehensive Cancer Center, Richmond

VCU Community Memorial Health Center, South Hill

Northwest Cancer Center - Main Campus, Crown Point

Northwest Oncology LLC, Dyer

Saint Catherine Hospital, Indianapolis

The Community Hospital, Munster

Women's Diagnostic Center - Munster, Munster

Northwest Cancer Center - Hobart, Hobart

Saint Mary Medical Center, Hobart

Northwest Cancer Center - Valparaiso, Valparaiso

Henry Ford Saint John Hospital - Macomb Medical, Macomb

Henry Ford Warren Hospital - Breast Macomb, Macomb

Henry Ford River District Hospital, East China Township

Henry Ford Health Warren Hospital, Warren

Henry Ford Madison Heights Hospital - Breast, Warren

Henry Ford Warren Hospital - GLCMS, Warren

Trinity Health Saint Joseph Mercy Hospital Ann Arbor, Ann Arbor

Huron Gastroenterology PC, Ypsilanti

Trinity Health IHA Medical Group Hematology Oncology - Brighton, Brighton

Trinity Health Medical Center - Brighton, Brighton

Chelsea Hospital, Chelsea

Trinity Health IHA Medical Group Hematology Oncology - Chelsea Hospital, Chelsea

Trinity Health Saint Mary Mercy Livonia Hospital, Livonia

Trinity Health IHA Medical Group Hematology Oncology - Canton, Canton

Trinity Health Medical Center - Canton, Canton

Trinity Health IHA Medical Group Hematology Oncology Ann Arbor Campus, Ypsilanti

Henry Ford Health Saint John Hospital, Detroit

Henry Ford Saint John Hospital - Breast, Grosse Pointe Woods

Henry Ford Saint John Hospital - Van Elslander, Grosse Pointe Woods

Cancer Hematology Centers - Flint, Flint

Genesee Hematology Oncology PC, Flint

Genesys Hurley Cancer Institute, Flint

MyMichigan Medical Center Saginaw, Saginaw

Oncology Hematology Associates of Saginaw Valley PC, Saginaw

Saint Mary's Oncology/Hematology Associates of West Branch, West Branch

MyMichigan Medical Center Tawas, Tawas City

Bronson Methodist Hospital, Kalamazoo

West Michigan Cancer Center, Kalamazoo

Beacon Kalamazoo Cancer Center, Kalamazoo

Bronson Battle Creek, Battle Creek

Corewell Health Lakeland Hospitals - Marie Yeager Cancer Center, Saint Joseph

Corewell Health Lakeland Hospitals - Niles Hospital, Niles

Trinity Health Muskegon Hospital, Muskegon

Cancer and Hematology Centers of Western Michigan - Norton Shores, Norton Shores

Corewell Health Grand Rapids Hospitals - Butterworth Hospital, Grand Rapids

University of Michigan Health - West, Wyoming

Corewell Health Reed City Hospital, Reed City

Munson Medical Center, Traverse City

Mary Greeley Medical Center, Ames

McFarland Clinic - Ames, Ames

UI Health Care Mission Cancer and Blood - Ankeny Clinic, Ankeny

McFarland Clinic - Boone, Boone

McFarland Clinic - Jefferson, Jefferson

McFarland Clinic - Marshalltown, Marshalltown

Iowa Methodist Medical Center, Des Moines

UI Health Care Mission Cancer and Blood - Des Moines Clinic, Des Moines

Mercy Medical Center - Des Moines, Des Moines

McFarland Clinic - Trinity Cancer Center, Fort Dodge

University of Wisconsin Carbone Cancer Center - Eastpark Medical Center, Madison

University of Wisconsin Carbone Cancer Center - University Hospital, Madison

Regions Hospital, Saint Paul

United Hospital, Saint Paul

Abbott-Northwestern Hospital, Minneapolis

Park Nicollet Clinic - Saint Louis Park, Saint Louis Park

Mercy Hospital, Coon Rapids

Fairview Southdale Hospital, Edina

Illinois CancerCare-Dixon, Dixon

Illinois CancerCare-Ottawa Clinic, Ottawa

Illinois CancerCare-Peru, Peru

Illinois CancerCare-Princeton, Princeton

Illinois CancerCare-Galesburg, Galesburg

Illinois CancerCare-Kewanee Clinic, Kewanee

Illinois CancerCare-Macomb, Macomb

Illinois CancerCare-Canton, Canton

Illinois CancerCare-Eureka, Eureka

Illinois CancerCare-Pekin, Pekin

Illinois CancerCare - Washington, Washington

Illinois CancerCare-Peoria, Peoria

Illinois CancerCare-Bloomington, Bloomington

Carle Cancer Center, Urbana

Carle at The Riverfront, Danville

Carle Physician Group-Mattoon/Charleston, Mattoon

Cancer Care Center of O'Fallon, O'Fallon

Memorial Hospital East, Shiloh

Illinois CancerCare-Carthage, Carthage

Carle Physician Group-Effingham, Effingham

Crossroads Cancer Center, Effingham

Cancer Care Specialists of Illinois - Decatur, Decatur

Southern Illinois University School of Medicine, Springfield

Springfield Clinic, Springfield

Springfield Memorial Hospital, Springfield

Missouri Baptist Sullivan Hospital, Sullivan

Washington University School of Medicine, St Louis

BJC Outpatient Center at Sunset Hills, Sunset Hills

Siteman Cancer Center-South County, St Louis

Missouri Baptist Medical Center, St Louis

Siteman Cancer Center at Christian Hospital, St Louis

Siteman Cancer Center at West County Hospital, Creve Coeur

Siteman Cancer Center at Saint Peters Hospital, City of Saint Peters

Parkland Health Center - Farmington, Farmington

Sainte Genevieve County Memorial Hospital, Sainte Genevieve

Saint Francis Medical Center, Cape Girardeau

University of Oklahoma Health Sciences Center, Oklahoma City

Kaiser Permanente-Fresno, Fresno

Kaiser Permanente-South San Francisco, South San Francisco

Kaiser Permanente-San Francisco, San Francisco

Kaiser Permanente-Fremont, Fremont

Kaiser Permanente Dublin, Dublin

Kaiser Permanente San Leandro, San Leandro

Kaiser Permanente-Vallejo, Vallejo

Kaiser Permanente-Walnut Creek, Walnut Creek

Kaiser Permanente-Oakland, Oakland

Kaiser San Rafael-Gallinas, San Rafael

Kaiser Permanente Medical Center - Santa Clara, Santa Clara

Kaiser Permanente-Santa Teresa-San Jose, San Jose

Kaiser Permanente-Modesto, Modesto

Kaiser Permanente-Santa Rosa, Santa Rosa

Kaiser Permanente-Roseville, Roseville

Kaiser Permanente Downtown Commons, Sacramento

Kaiser Permanente-South Sacramento, Sacramento

Kaiser Permanente Moanalua Medical Center, Honolulu

Providence Willamette Falls Medical Center, Oregon City

Providence Newberg Medical Center, Newberg

Providence Portland Medical Center, Portland

Providence Saint Vincent Medical Center, Portland

UMass Memorial Medical Center - University Campus, Worcester