Some recent reappraisals of the prognostic value of some clinical and histological features, based on large numbers of patients studied in many trials, has led the AJCC to change the staging system.
No longer is the level of invasion of the primary melanoma used, but rather the depth and ulceration characteristics of the primary growth for the T stage. Further, the number of involved regional lymph nodes rather their dimensions will be given more weight in the new staging system, as will macroscopic versus microscopic involvement of nodes. With regard to the presence of distant metastatic disease, the site of the metastases and the level of the serum lactate dehydrogenase will be given more prognostic weight in the new system. The new staging system is regarded as being a more accurate , in relation to ultimate prognosis.