| Abbreviation | Definition |
|---|---|
| OASIS | Oncology and Sexuality Intimacy and Survivorship |
| OASIS | Ovarian Awareness, Support, Involvement, and Survivorship |
| OATU | oncology acute toxicity unit |
| OBD | Oncology Biomarker Development |
| OCF | Oncology Computing Facility |
| OCF | Orange County Foundation for Oncology |
| OCIA | Ovarian Carcinoma Immunoreactive Antigen |
| OCIS | Oncology Clinical Information Systems |
| OCM | Oncology Care Model |
| OCMU | Oncology Center Mansoura University |
| OCN | Oncology Certified Nurse |
| OCNA | Ovarian Cancer National Alliance |
| OCRF | Ovarian Cancer Research Fund |
| OCTO | Oncology Clinical Trials Office |
| OCV | Oncology Clinics Victoria |
| OD | Oligodendrogliomas |
| OD | Ollier disease |
| OEB | Open Excisional Biopsy |
| OECI | Organization of European Cancer Institutes |
| OHC | Oncology Hematology Care |