Department of Dermatology (370), Radboud University Medical Center, P.O. Box 9101, NL-6500 HB, Nijmegen, the Netherlands; Department for Health Evidence (133), Radboud University Medical Center, P.O. Box 9101, NL-6500 HB, Nijmegen, the Netherlands.
Br J Dermatol. 2014 Apr;170(4):874-7. doi: 10.1111/bjd.12898.
In the transition from the sixth to the seventh edition of the American Joint Committee on Cancer (AJCC) melanoma staging system, mitotic activity was incorporated, while Clark level of invasion was abandoned.
To investigate the effect of this change on the pathological tumour (pT)1 substaging of primary cutaneous melanomas and the possible clinical implications.
Patients with pT1 melanomas, diagnosed in the period January 2003 to March 2011, were selected from a population-based cohort study on cutaneous melanoma in the eastern part of the Netherlands. The pT1 melanomas were systematically reviewed by an expert pathologist and classified according to both the sixth and the seventh editions of the AJCC staging system. The shift of melanomas between pT1 substages, classified according to the two staging systems, was determined.
In total, 260 pT1 melanomas were included. Overall 28% (57/207) of all pT1a melanomas shifted to pT1b when classified according to the new seventh staging classification, because of the presence of mitoses. Some 32% (17/53) of all pT1b melanomas shifted to pT1a. The percentage of pT1b melanomas relative to all pT1 melanomas increased from 20% to 36%.
The addition of mitotic activity to the pathological staging system, according to the seventh edition of the AJCC staging system, resulted in a considerable change in the classification of thin cutaneous melanomas. This shift has clear clinical implications, as it is advised in the Dutch guideline that patients with pT1b melanoma should be offered a sentinel lymph node biopsy.
在从第六版到第七版的美国癌症联合委员会（AJCC）黑色素瘤分期系统中，加入了有丝分裂活性，而放弃了Clark 侵袭水平。
研究这一变化对原发性皮肤黑色素瘤 pT1 亚分期的影响及可能的临床意义。
从荷兰东部一项皮肤黑色素瘤的基于人群的队列研究中选择了 2003 年 1 月至 2011 年 3 月期间诊断的 pT1 黑色素瘤患者。由一名专家病理学家对 pT1 黑色素瘤进行系统回顾，并根据第六版和第七版 AJCC 分期系统进行分类。确定根据两种分期系统分类的 pT1 亚分期中黑色素瘤的转移情况。
共纳入 260 例 pT1 黑色素瘤。总体而言，28%（57/207）的所有 pT1a 黑色素瘤根据新的第七分期分类被归类为 pT1b，因为存在有丝分裂。约 32%（17/53）的所有 pT1b 黑色素瘤转移到 pT1a。pT1b 黑色素瘤占所有 pT1 黑色素瘤的比例从 20%增加到 36%。
根据第七版 AJCC 分期系统，将有丝分裂活性纳入病理分期系统，导致薄型皮肤黑色素瘤的分类发生了相当大的变化。这种转变具有明确的临床意义，因为荷兰指南建议对 pT1b 黑色素瘤患者进行前哨淋巴结活检。
