SEER Inquiry System - Report
Produced: 12/28/2024 12:43 PM
Question 20120020
Inquiry Details
References:
2007 MP/H Rules
Question:
MP/H Rules/Multiple primaries--Breast: How many primaries are to be accessioned when a lumpectomy shows a single 6 mm "infiltrating mammary adenocarcinoma, histologic type: ductal (tubular)" tumor, and "peritumoral microscopic foci of solid type ductal carcinoma in situ"? See Discussion.
Discussion:
Per SINQ 20091117, tubular (ductal) carcinoma would be coded to 8211/3 [tubular]. However, in that case the tubular/ductal carcinoma is composed of a single tumor. In this case, the foci of DCIS were specifically stated to be peritumoral, and not a part of the infiltrating tubular carcinoma.
Are these microscopic foci of DCIS a separate primary per Rule M12 and SINQ 20110092 [two primaries are accessioned when one tumor is invasive and another is in situ, and histology codes differ at 1st, 2nd or 3rd numbers]? Does the size of the DCIS matter when there are two distinct histologies? Abstracting a second primary for these microscopic foci seems like over-reporting.
Answer:
The following answers depend on what this pathologist means by "ductal (tubular)." According to the WHO classification, tubular is not a duct subtype. Check with the pathologist if possible to determine if the intended meaning is "tubular carcinoma" or "duct carcinoma".
If the pathologist uses the expression "ductal (tubular)" as an equivalent of "tubular carcinoma": Accession two primaries, a tubular carcinoma [8211/3] and a ductal carcinoma in situ, solid type [8230/2].
For cases diagnosed 2007 and later, the steps used to arrive at this decision are:
Determine the provisional histologies of these tumors in order to apply the Multiple Primary rules. Open the Multiple Primary and Histology Coding Rules manual. For a breast primary, use the Breast Histology rules to determine the histology codes because there are site specific rules for breast primaries.
Determine the histology of in situ carcinoma, solid type ductal carcinoma in situ. Start at Rule H1. The rules are intended to be reviewed in consecutive order within the applicable Module. Code the more specific histologic term when the diagnosis is intraductal carcinoma and a type of intraductal carcinoma. Solid is a specific type of DCIS. The histology is 8230/2.
Determine the histology of the invasive carcinoma, tubular carcinoma. Start at Rule H10. Code the histology when only one histologic type is identified, Tubular carcinoma was the only type identified. The histology is 8211/3.
Go to the Breast MP rules found in the Multiple Primary and Histology Coding Rules Manual after determining the histology of each tumor. Start at the MULTIPLE TUMORS Module, Rule M4, because the patient has a single invasive tumor and separate foci of DCIS. These tumors have ICD-O-3 histology codes that are different at the third (xxx) number and are, therefore, multiple primaries.
If the pathologist uses the expression "ductal (tubular)" as an equivalent of "duct carcinoma": Accession a single primary, a duct carcinoma [8500/3].
For cases diagnosed 2007 and later, the steps used to arrive at this decision are:
Go to the Breast MP rules found in the Multiple Primary and Histology Coding Rules Manual. Start at the MULTIPLE TUMORS Module, Rule M4 because the patient has a single invasive duct carcinoma and separate foci of solid type ductal carcinoma in situ. Multiple intraductal and/or duct carcinomas are a single primary. Table 1 identifies solid type as a specific type of intraductal carcinoma.
Go to the Breast Histology rules found in the Multiple Primary and Histology Coding Rules Manual. Start at the MULTIPLE TUMORS ABSTRACTED AS A SINGLE PRIMARY Module, Rule H20. Code the invasive histology when both invasive and in situ tumors are present. Code the histology as 8500/3 [duct carcinoma].