Data Last Updated: June 9, 2025

NAACCR Item #3893: Mitotic Rate Melanoma

Item # Length Source of Standard Section Name Year Implemented Version Implemented XML NAACCR ID Parent XML Element
3893 2 NAACCR Stage/Prognostic Factors 2018 18 mitoticRateMelanoma Tumor
Required Status:

NPCR Collect: No recommendation
CoC Collect: Required, site specific
SEER Collect: Required, site specific
CCCR Collect: Required, site specific; when available

Description
Mitotic Rate Melanoma, the number of mitoses per square millimeter based on pathological evaluation, is a prognostic factor for melanoma of the skin.
Rationale
Mitotic Rate Melanoma is a Registry Data Collection Variable in AJCC. It was previously collected as Melanoma Skin, CS SSF# 7.
Allowable Values
00-99, X1, X2, X3, X4, X7, X8, X9
Codes
Code Description
00 0 mitoses per square millimeter (mm) Mitoses absent No mitoses present
01-99 1 - 99 mitoses/square mm (Exact measurement in mitoses/square mm)
X1 100 mitoses/square mm or more
X2 Stated as "less than 1 mitosis/square mm" Stated as "nonmitogenic"
X3 Stated as "at least 1 mitosis/square mm" Stated as "mitogenic"
X4 Mitotic rate described with denominator other than square millimeter (mm)
X7 Test ordered, results not in chart
X8 Not applicable: Information not collected for this case (If this information is required by your standard setter, use of code X8 may result in an edit error.)
X9 Not documented in medical record Mitotic Rate Melanoma not assessed or unknown if assessed
Code Notes
Each Site-Specific Data Item (SSDI) applies only to selected primary sites, histologies, and years of diagnosis. Depending on applicability and standard-setter requirements, SSDIs may be left blank.