Neoplasm of uncertain behavior of carotid body

This code signifies a tumor of the carotid body whose biological behavior cannot be definitively classified as benign or malignant based on current diagnostic information. These neoplasms originate from chemoreceptor cells located at the carotid artery bifurcation. While often slow-growing, their potential for local invasion or metastasis remains undetermined.

Apply this code when pathology reports or clinical findings indicate a carotid body tumor with ambiguous features, preventing a clear diagnosis of benign paraganglioma or malignant paraganglioma. Documentation must explicitly state "uncertain behavior," "undetermined behavior," or similar terminology for the carotid body neoplasm.

• Ensure documentation clearly specifies the carotid body as the tumor's origin.
• Do not use this code if the tumor is definitively diagnosed as benign (e.g., D35.6) or malignant (e.g., C75.4).
• Review the pathology report carefully for terms like "atypical," "borderline," or "uncertain malignant potential" to support this classification.