SEER Inquiry System - Report
Produced: 11/27/2024 5:26 PM
Question 20071040
Inquiry Details
References:
2007 MP/H Rules. Melanoma (M6, M7)
Question:
Discussion:
Rule M6 clearly states that an invasive melanoma occurring more than 60 days after an in situ melanoma is a multiple primary. However M7 states that any melanomas diagnosed more than 60 days apart are multiple primaries. Since M7 does not state malignant melanomas diagnosed more than 60 days apart, this implies that any scenario:
in situ following an invasive,
invasive following an in situ,
in situ following an in situ,
or invasive following an invasive
are all multiple primaries if more than 60 days apart. If that is the intent of M7, then M6 is totally unnecessary. If the intent of M7 is only for an invasive following an invasive, then the word malignant needs to be inserted as the first word of rule M7.
Answer:
For cases diagnosed 2007 or later, M7 is intended to apply to in situ and invasive melanomas. Therefore, M6 and M7 are repetitive.
This will be corrected when revisions are made to the MP/H rules. In the meantime, both M6 and M7 result in multiple primaries so it does not matter which rule is used.