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SEER Inquiry System - Report
Produced: 01/10/2026 11:55 PM
Question 20230026
Inquiry Details
References:
Solid Tumor Rules. Other Sites, March 2023 update
Question:
Solid Tumor Rules/Multiple Primaries--Prostate: How many primaries should be abstracted, and which M rule applies when a patient is diagnosed with intraductal carcinoma of the prostate on biopsy followed by invasive adenocarcinoma on radical prostatectomy more than 60 days later? See Discussion.
Discussion:
Example: A prostate core biopsy showed intraductal carcinoma in 09/2022, which is an in situ tumor. A core biopsy again showed intraductal carcinoma in 12/2022. The subsequent radical prostatectomy in 04/2023, revealed multiple foci of invasive prostate adenocarcinoma with extensive intraductal carcinoma.
Per Solid Tumor Rules, Other Sites, Rule M3, acinar adenocarcinoma of the prostate is always a single primary. Note 4, this rule applies to subtype variants of acinar adenocarcinoma listed in Table 3, which has intraductal/ductal as a variant subtype of acinar adenocarcinoma. Does rule M3 apply to incidence cases (an invasive tumor following an in situ tumor)?
Answer:
Rule M1 applies because we don't know if there are separate tumors or separate foci within a single tumor. This is a single primary coded 8140/3. The prostate rules will be reviewed for an addition to cover this situation.
