| Providence Regional Cancer System-Aberdeen | Aberdeen | 1 |
| PeaceHealth Saint Joseph Medical Center | Bellingham | 2 |
| Providence Regional Cancer System-Centralia | Centralia | 1 |
| Swedish Cancer Institute-Edmonds | Edmonds | 1 |
| Providence Regional Cancer Partnership | Everett | 1 |
| Swedish Cancer Institute-Issaquah | Issaquah | 2 |
| Kadlec Clinic Hematology and Oncology | Kennewick | 1 |
| Providence Regional Cancer System-Lacey | Lacey | 1 |
| PeaceHealth Saint John Medical Center | Longview | 1 |
| Jefferson Healthcare | Port Townsend | 1 |
| Valley Medical Center | Renton | 1 |
| FHCC South Lake Union | Seattle | 1 |
| Fred Hutch Cancer Center | Seattle | 6 |
| Ivy Center for Advanced Brain Tumor Treatment; Swedish Neuroscience Institute | Seattle | 1 |
| Seattle Children's Hospital | Seattle | 17 |
| Swedish Medical Center | Seattle | 1 |
| Swedish Medical Center-Ballard Campus | Seattle | 1 |
| Swedish Medical Center-Cherry Hill | Seattle | 1 |
| Swedish Medical Center-First Hill | Seattle | 2 |
| University of Washington | Seattle | 1 |
| University of Washington Fred Hutchinson Cancer Center | Seattle | 1 |
| University of Washington Medical Center | Seattle | 1 |
| University of Washington Medical Center - Montlake | Seattle | 1 |
| PeaceHealth United General Medical Center | Sedro-Woolley | 1 |
| Providence Regional Cancer System-Shelton | Shelton | 1 |
| Saint Joseph Medical Center Hematology and Oncology - Silverdale | Silverdale | 1 |
| Providence Sacred Heart Medical Center and Children's Hospital | Spokane | 4 |
| Madigan Army Medical Center | Tacoma | 2 |
| Mary Bridge Children's Hospital and Health Center | Tacoma | 4 |
| Northwest Medical Specialties | Tacoma | 1 |
| PeaceHealth Southwest Medical Center | Vancouver | 1 |
| Providence Saint Mary Regional Cancer Center | Walla Walla | 1 |
| North Star Lodge Cancer Center at Yakima Valley Memorial Hospital | Yakima | 1 |
| Providence Regional Cancer System-Yelm | Yelm | 1 |