Neoplasm of uncertain behavior of right breast

This code signifies the presence of an abnormal growth in the right breast where the pathologist cannot definitively classify it as benign or malignant based on current microscopic examination. It indicates that the biological behavior of the lesion is currently indeterminate.

Apply this code when pathology reports describe a right breast lesion as "atypical," "proliferative lesion of uncertain malignant potential," or "neoplasm of uncertain behavior." This is typically used after a biopsy or excision when further follow-up or diagnostic procedures are anticipated to determine the definitive nature of the growth.

• Ensure the documentation explicitly states "right breast" and "uncertain behavior" for accurate laterality and behavior assignment.
• Do not use this code if the pathology definitively identifies the lesion as benign (e.g., fibroadenoma) or malignant (e.g., invasive ductal carcinoma).
• Review subsequent pathology reports carefully; this code may be superseded by a more definitive diagnosis upon further analysis or re-excision.