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SEER Inquiry System - Report
Produced: 12/09/2025 12:50 AM
Question 20010012
Inquiry Details
References:
#1: SEER PCM,3rd Ed,Rev 1, 127b, 129b, F-22. January 2003
#2: 2004 SEER Manual, C-485, C-486. Appendix C
Question:
Surgery of Primary Site--Breast: What code is used to represent this field for a breast primary treated with a "bilateral mastectomy"? See discussion.
Discussion:
Pt diagnosed with rt breast primary opted to be treated with rt modified radical mastectomy and lt simple mastectomy. Path revealed invasive ductal carcinoma on the rt and ductal carcinoma in situ on the lt. Path reported 14 axillary lymph nodes were found in the mastectomy specimen.
Answer:
There are two primaries. For cases diagnosed 1/1/2003 and after: For the rt breast, code Surgery of Primary Site to 51. The contralateral left breast malignancy is not involved with the right breast primary by either direct extension or metastasis. Codes 42 and 52 are used to capture prophylactic mastectomy of the opposite noncancerous breast. In this case, the opposite breast has cancer so these codes cannot be used. Code Scope of Regional Lymph Node Surgery to 5 and Surgical Procedure of Other Site to 0.
For the lt breast, code Surgery of Primary Site to 41, Scope of Reg LN Surgery to 0, and Surgical Procedure of Other Site to 0.
History:
For cases diagnosed 1998-2002: For the rt breast, code Surgery of Primary Site to 51, Scope of Reg LN Surg to 2, # Reg LNs Examined to 14, and Surg of Other Sites/LNs to 0. For the lt breast, code Surgery of Primary Site to 41, Scope of Reg LN Surg to 0, # Reg LNs Examined to 00, and Surg of Other Sites/LNs to 0.
