An oncologist is a type of doctor who deals with patients afflicted with one or various types of cancer. His/her work involves consultation, diagnosis, application of chemotherapy and coordinating with other doctors involved in treatment etc. This is how the phone greetings for oncologist should be like:
There is no definitive answer here, but you should include one of the two at the beginning of your message based on what makes the most sense.

For a medical office, call types may include billing, emergencies, appointments, cancellations, etc. 2. Determine How To Best Route Calls The best method of routing your medical office calls will depend on your office size and budget. If you have a small staff, setting up a standard voicemail greeting system may be a more practical approach. For a larger health organization with multiple departments, it makes more sense to route calls to their intended destinations by using an auto attendant. For example, “If you have a question about billing, press 1. If you’d like to schedule an appointment, press 2. If this is a medical emergency, press 0 for an operator.” If you want every caller or patient to experience a professional and compassionate call, you may consider working with a medical office answering service. You can forward calls to an answering service after business hours, on holidays, during overflow, or any other time you may need help answering calls. 3. Draft A Script
You might also consider giving them the option to skip your voicemail message completely by pressing another key (again, check with IT). You also want to make callers aware what you will return their call, instead of telling them that you will try to return their call--and let them know when you are likely to do it, if possible. If necessary, provide additional or emergency information in your voicemail greetings. My dentist, for example, lists his cell phone number for emergencies.