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SEER Inquiry System - Report
Produced: 09/11/2025 5:04 PM
Question 20150041
Inquiry Details
References:
2007 MP/H Rules
Question:
MP/H Rules/Multiple primaries--Breast: Does rule M10 apply in this situation?
L breast biopsy = INVASIVE DUCTAL CARCINOMA
L breast simple mastectomy = 2.0 cm INVASIVE DUCTAL CARCINOMA with an incidental finding of separate 1.0 cm INVASIVE LOBULAR CARCINOMA; pathologist specifically states the tumors are morphologically different. The tumors are both pure Ductal/pure Lobular.
Discussion:
Answer:
Yes, Breast rule M10 applies. This case is a single primary.
Follow the MP/H rules even though the "pathologist specifically states the tumors are morphologically different" so that situations like this are reported consistenty accross cancer registries, regions, and states for consistent national reporting.
Cancer Site Category:
Breast
Data Item Category:
N/A
Other Category:
Multiple primaries
Year:
2015
