Comparison of AJCC seventh edition and AJCC eighth edition staging systems: melanoma-specific survival of patients with stage I and II melanoma by T subcategory. All patients with T1N0 melanoma were included. Patients with T2 to T4 melanoma were included only if they had negative sentinel lymph nodes. aWith permission from Gershenwald JE, Scolyer RA, Hess KR, Sondak VK, et al. Melanoma staging: evidence-based changes in the American Joint Committee on Cancer eighth edition cancer staging manual. CA Cancer J Clin. 2017; 67:472–491.bWith permission from Balch CM, Gershenwald JE, Soong SJ, et al. Final version of 2009 AJCC melanoma staging and classification. J Clin Oncol. 2009;27:6199–6206.