Green A
Epidemiology Department, Queensland Institute of Medical Research, Brisbane, Australia.
Cancer Causes Control. 1992 Nov;3(6):513-6. doi: 10.1007/BF00052747.
Although sun exposure is believed to be associated causally with cutaneous melanoma, the high incidence on less sun-exposed areas such as the back, as well as on chronically exposed sites such as the face, suggests that the association with sunlight is less straightforward than for other skin cancers. To explain this enigmatic site distribution, a theory of site-dependent susceptibility of melanocytes to malignant transformation is proposed. As possible evidence, all melanomas diagnosed in the state of Queensland, Australia, over a one-year period were surveyed for histologic evidence of benign melanocytic nevus cells adjacent to the melanoma, and analyzed according to anatomic distribution. Results showed a regional variation in the proportion of melanomas with adjacent nevi not explicable by regional variation in nevus density, which suggests that there is a varying susceptibility of nevi to malignant change. Given that nevus cells are equivalent to melanocytes, this finding would support the hypothesis that melanocytes at-large have a differential response to the mitogenic stimulus of sunlight according to anatomic site.
尽管人们认为阳光照射与皮肤黑色素瘤存在因果关联，但在背部等阳光照射较少的部位以及面部等长期暴露部位黑色素瘤的高发病率表明，与其他皮肤癌相比，黑色素瘤与阳光的关联并非那么直接。为了解释这种神秘的部位分布情况，有人提出了一种关于黑素细胞对恶性转化的部位依赖性易感性的理论。作为可能的证据，对澳大利亚昆士兰州一年内诊断出的所有黑色素瘤进行了调查，以寻找黑色素瘤附近良性黑素细胞痣细胞的组织学证据，并根据解剖分布进行分析。结果显示，有相邻痣的黑色素瘤比例存在区域差异，而这种差异无法用痣密度的区域差异来解释，这表明痣发生恶性变化的易感性各不相同。鉴于痣细胞等同于黑素细胞，这一发现将支持这样的假设，即总体而言，黑素细胞根据解剖部位对阳光的促有丝分裂刺激有不同反应。
