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SEER Inquiry System - Report
Produced: 01/02/2026 7:00 PM
Question 20230058
Inquiry Details
References:
Solid Tumor Rules. Breast, 2023 Update; General Instructions
Question:
Solid Tumor Rules/Multiple Primaries--Breast: How many primaries should be accessioned for a patient with known history of right breast carcinoma in 2018 followed by 2022 biopsy proven right and left breast invasive ductal carcinoma if the physician states this is a right breast primary with widespread metastasis including the left breast? See Discussion.
Discussion:
The patient was initially diagnosed with invasive mammary carcinoma of the right breast in 2018, treated with lumpectomy, sentinel node biopsy, radiation, and hormones. Hormones were discontinued early due to dysfunctional uterine bleeding.
Answer:
This is a single primary according to the Solid Tumor Rules.
- Breast Solid Tumor Rule M18 applies to the occurrence of the second right breast tumor (single primary).
- Apply the Solid Tumor Rules, General Instructions, that state the rules are NOT used for tumor(s) described as metastases. Tumor in a metastatic site is not counted when applying the Solid Tumor rules. In this case, the physician stated that this is a right breast primary with widespread metastasis to the left breast.
Cancer Site Category:
Breast
Data Item Category:
N/A
Other Category:
Multiple primaries, Solid Tumor Rules (2018, 2021)
Year:
2023
