Interobserver Variation in the Histopathologic Reporting of Key Prognostic Parameters, Particularly Clark Level, Affects Pathologic Staging of Primary Cutaneous Melanoma

Although there was a high level of agreement between pathologists in the assessment of overall pathologic stage, the significant level of discordance in pathologic substaging suggests that accurate and reliable substage-based prognostic prediction may not be possible in all cases. It will be important to consider these issues in future revisions of the American Joint Committee on Cancer melanoma staging system.