Site-Specific Factor 3

Mitotic Count

Notes

**Note 1:** The mitotic count reflects the potential aggressiveness or prognosis of endocrine pancreatic tumors. This site-specific factor presumes the denominator of 10 high power fields (HPF) or its equivalent, so just the numerator (the mitotic count) is coded here. * For other schemas in which mitotic count is collected, the denominator may vary. An HPF usually has a magnification objective of 40 (a 40x field) **Note 2:** Record mitotic count, to the nearest tenth of a mitosis, as documented in the pathology report. * For example, a mitotic count of 6/10 HPF **Note 3:** Code the specific mitotic count only per 10 HPF; assume the denominator is 10 HPF if not specified. * Use code 996 only if the mitotic count is expressed with a specific denominator other than 10 HPF **Note 4:** Although mitotic count is generally documented for neuroendocrine tumors, if the mitotic count is available for a non-endocrine tumor, code the count. * If it is not available (endocrine or non-endocrine tumor), code 999

Default

988

NAACCR Item

NAACCR #2900
Code Description
000 0 mitoses per 10 high-power fields (HPF) (40x field)
Mitoses absent, no mitoses present, no mitotic activity
001-008 0.1 - 0.8 mitosis per 10 HPF (40x field)
0.1 - 0.8 mitosis per
009 0.9 mitosis per 10 HPF (40x field)

Stated as less than 1 mitosis per 10 HPF (40x field)
010-100 1-10 mitoses per 10 HPF (40x field)
110 11 or more mitoses per 10 HPF (40x field)
988 Not applicable: Information not collected for this case
990 Specific number not stated, described less than or equal to 4
mitoses per 10 HPF (40x field)

Stated as low mitotic count or rate with no specific number
992 Specific number not stated, described as more than 4 mitoses per 10 HPF (40x field)

Stated as high mitotic count or rate with no specific number
996 Mitotic count described with denominator other than 10 HPF (40x field)
998 No histologic specimen from primary site
999 Unknown or no information
Not documented in patient record