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SEER Inquiry System - Report
Produced: 10/12/2025 7:15 PM
Question 20150037
Inquiry Details
References:
#1: WHO Class Breast Tumors
#2: ICD-O-3.2 Update for 2021
Question:
Reportablility--Breast: Is lobular neoplasia reportable as lobular carcinoma in situ? See Discussion.
Discussion:
According to College of American Pathologists (CAP), lobular neoplasia is also known as lobular carcinoma in situ. In a previous SEER question 20041089, it was stated that they were not the same and should not be reported unless it was a Grade 3. I assume this has changed and we are to report lobular neoplasia as lobular carcinoma in situ, is this correct?
Answer:
For cases diagnosed 2021 or later
Lobular neoplasia (LN II and LN III) and lobular intraepithelial neoplasia (LIN II and LIN III) are reportable and coded 8520/2.
History:
For cases diagnosed prior to 2021
According to the WHO classification of breast tumors, "lobular neoplasia (LN) refers to the entire spectrum of atypical epithelial lesions originating in the terminal-duct lobular unit…" Report the case when lobular carcinoma in situ (LCIS) is stated. When LN or lobular intraepithelial neoplasia (LIN) are described using the three-grade system, report LN/LIN grade 3. Only LN/LIN grade 3 is reportable since those terms are analogous to ductal intraepithelial neoplasia grade 3 (See Intraepithelial neoplasia 3, ductal in ICD-O-3). WHO Classifications of Tumors are the preferred references for questions like this.
