Site-Specific Factor 3

Grade - Melanoma Origin


**Note 1:** Grade coded in this field describes whether the melanoma arises from a pre-existing lesion (primary acquired melanosis, PAM) or appears "de novo", without any pre-existing lesion. This is not the same as the histologic grade defined in the ICD-O, designating degrees of differentiation from normal tissue such as "well differentiated" or "poorly differentiated", which is coded in the traditional grade field. **Note 2:** Tumors of Grade 0, Primary acquired melanosis without cellular atypia, and Grade 1, Conjunctival nevus, are not reportable to the cancer registry. Tumors of Grade 2, Primary acquired melanosis with cellular atypia (epithelial disease only) are reportable and may be coded as 8741/2. **Note 3:** Code this field only from a statement of grade describing PAM with atypia or de novo melanoma, documented by the managing physician or the pathologist in the record. * Do not interpret or attempt to assign grade based on the histologic diagnosis of the tumor




NAACCR #2900
Code Description
020 Grade 2
Primary acquired melanosis (PAM) with cellular atypia (epithelial disease only)
Confined to epithelium
030 Grade 3
PAM with epithelial cellular atypia and invasive melanoma
040 Grade 4
De novo malignant melanoma
988 Not applicable: Information not collected for this case
998 No pathologic examination of primary site tumor
999 Grade X
Unknown or no information
Not documented in patient record