The oncologist keeps insisting on chemo but i would rather have surgery only for breast cancer, i would like another opinion is it always necessary?

Autonomy: No one, not even the most zealous oncologist, can force you to do anything you don't want to do. Only a complete fool would refuse surgery or the equivalent for a breast cancer, but the decision to include chemotherapy weighs the benefits (which should be spelled out for you) against the unpleasantness and difficulties. Get two more opinions.

Another opinion A+!: Your body is your own, and you make your own decisions. The treatment approach depends on many factors, including the extent and type of your tumor. You should get a second opinion, especially if you are uncertain of your own approach to your illness. Just as importantly, you should have a second opinion of your pathology (diagnosis), as the pathologist's interpretation is essential.

Not always, but...: ...If you are not comfortable with your oncologist's opinion, you should get a second one. Unfortunately, surgery is rarely sufficient to treat breast cancer. More than half of all breast cancer patients require chemotherapy, and even more are given anti-estrogen therapy. The breast is but a battleground; the war is won or lost in the whole body. There is no better means for systemic rx than chemo.

Chemotherapy: My influence "risks". Has your oncologist explained the benefit, what you "risk" by not taking the recommended treatment? If i were you, i'd seek two other opinions. On the other hand, if the oncotype test, and 3 doctors would *not* influence your decision, don't waste your money and their time. But remember the adage about "one treating themselves, has a fool for a patient.".