Dad w/tongue ca having symptoms tomorrow by e.N.T dr. My sister suggest we see the oncologist first and possibly have him do the surgery. Any suggestions?

She may be right. Medical oncologists are specialists who decide about use of chemotherapy. Your dad may or may not need chemo, it depends on the stage of his cancer. If his cancer is stage-3 then he should be seen by a medical oncologist. Stage 1 and 2 can be managed well by ENT specialist alone.