SEER Inquiry System - Question 20170007 Details

Per Rule M8, this is a single primary as there are multiple urothelial tumors as outlined in Table 1 (papillary urothelial carcinoma [8130] and sarcomatoid urothelial carcinoma [8122]) simultaneously present in multiple urinary organs (bladder, ureter and renal pelvis). As Rule M8 indicates these are a single primary, despite the histologies differing at the third digit (8130 vs 8122), then Rule H14 (Code the histology of the most invasive tumor) seems to be the most applicable histology rule. Following Rule H14 (in the Text version of the MP/H Rules), the histology would be coded as 8122 (sarcomatoid urothelial carcinoma) since the renal pelvis tumor was the most invasive tumor present.

However, in both the Matrix and Flowchart versions of the MP/H Rules, Rule H14 contains a note (missing from the Text version) that states that this rule should only be used when the first three numbers of the histology codes are identical (This is a single primary). Rule M8 clearly tells us these are a single primary, despite the differences at the third digit of the histology. Further defaulting to Rule H15 (Code the numerically higher histology code) in this case would ignore the histology of the tumor with the worse prognosis (the most invasive tumor). Was this note included in the Matrix and Flowchart versions in error?