Other specified type of carcinoma in situ of left breast

This code signifies the presence of abnormal, non-invasive cancer cells confined to the ducts or lobules of the left breast, but which do not fit the criteria for ductal carcinoma in situ (DCIS) or lobular carcinoma in situ (LCIS). It represents a pre-invasive form of breast cancer where the malignant cells have not spread beyond their original location.

Use this code when pathology reports confirm a diagnosis of carcinoma in situ of the left breast that is explicitly described as "other specified type," and not otherwise classifiable as DCIS or LCIS. Documentation must clearly indicate the left breast as the affected side and specify the "other" nature of the in situ carcinoma.

• Ensure the pathology report explicitly states "left breast" and "other specified type of carcinoma in situ."
• Do not use this code for DCIS (D05.1-) or LCIS (D05.0-) of the left breast; specific codes exist for those types.
• Verify laterality. If the documentation does not specify left or right, query the provider for clarification.