I submitted a claim for a radiation therapy (RT) for treatment of a secondary neuroendocrine tumor. The pathology states, "small cell neuroendocrine carcinoma". Medicare does not list these codes (209 series) as medically necessary for RT. The physician said that it is "small cell" and should not be coded as neuroendocrine (209.30) but as metastatic small cell carcinoma (198.3). Any comments?