Wiki Gyn Oncology - Physician billing for continued treatment in the postoperative period

Best answers
I am a coder in a gyn oncology physician practice. We have continuing issues billing for additional treatment during a postoperative period. Our providers are surgeons who also supervise chemotherapy. When we bill for treatment planning or pre-chemo visits during the postoperative period, our claims are routinely denied, even when billed with a 24 modifier. We often have to submit documentation, and have varying degrees of success with these appeals. How do other practices handle this issue?