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《皮肤病学档案》十二月刊中有论文称，婴儿期因黄疸接受过光线疗法后，儿童期发生皮肤痣的可能性增高。其中某些痣是发展为皮肤黑色素瘤的危险因素。

胆红素是红细胞正常分解后的副产品，如果胆红素在新生儿肝脏不能正常代谢，即堆积于血液中，使皮肤、巩膜及粘膜黄染，称为黄疸或高胆红素血症。约有45%至60%健康儿童及80%早产儿会发生黄疸。婴儿被放在蓝光箱内，接受蓝光照射后，非结合胆红素转化为结合胆红互并排出体外，从而达到治疗目的。以前曾有一些研究探讨了这一疗法的安全性，但并没有注意到光疗对皮肤的影响。

法国Bichat-Claude Bernard医院 Emmanuelle Matichard博士及其同事的研究包括58名8至9岁法国儿童的黑素细胞痣情况，其中18名儿童在新生儿期曾接受过蓝光治疗。另外40名未接受过光疗的儿童做为对照组。研究人员询问了所有儿童及其家长有关光疗、阳光暴露史及应用防晒霜的情况。皮肤科专家对这些儿童进行了体检，记录了他们的肤色、眼睛颜色、发色、皮肤类型及皮肤痣的数量和大小。

结果发现， 63%儿童皮肤有痣，为2毫米或更大，平均为每人皮肤痣的数目2.09个。接受过光疗的儿童2毫米大小皮肤痣的数目（平均3.5）明显高于未接受光疗组（平均1.45）。当分析仅限于大小为2至5毫米的痣时，光疗与痣数目之间的联系更为明显。

研究人员称，直径大于5毫米的痣大多为先天性的，很有可能与遗传倾向有关。小于2毫米的痣可能是近期发生的，早期产生的痣会更大。日光爆晒、尤其是假期中的日光浴，也和各种大小的痣的数目有关。发色浅与小于2毫米的痣的数量有关。

此研究并未探讨光疗是否增加成人期黑色素瘤的风险，两组之间皮肤痣的数目差别很小，也许不能改变发展为癌症的风险。更进一步的研究或许能够明确这种关系。研究人员称，后天形成的痣数目增多与黑色素瘤风险增高有关。详细评价儿童期痣的发生因素，会有益于判断高危人群从而加以预防。进一步研究应该以黑色素瘤与光疗的关系为重点。

Phototherapy for neonatal jaundice associated with increased risk of skin moles in childhood

Children who received light therapy (phototherapy) for jaundice as infants appear to have an increased risk of developing skin moles in childhood, according to a report in the December issue of Archives of Dermatology, one of the JAMA/Archives journals. Some types of moles are risk factors for developing the skin cancer melanoma.

Jaundice or hyperbilirubinemia occurs when bilirubin, a yellow pigment created as a byproduct of the normal breakdown of red blood cells, cannot yet be processed by a newborn抯 liver and builds up in the blood, turning the skin, whites of the eyes and mucous membranes yellow. The condition affects between 45 percent and 60 percent of healthy babies and as many as 80 percent of infants born prematurely, according to background information in the article. During phototherapy, the treatment of choice for jaundice, babies are placed under blue lights (bili lights) that convert the bilirubin into compounds that can be eliminated from the body. Studies have been performed to assess the safety of this therapy, but many have not focused on its effects on the skin, the authors write.

Emmanuelle Matichard, M.D., Bichat-Claude Bernard Hospital, Saint-Antoine Hospital, Assistance Publique-H魀itaux de Paris, and colleagues assessed the presence of melanocytic nevi (moles) in 58 French children who were 8 or 9 years old at the time of the study. Eighteen children had phototherapy as newborns; 40 who were the same age but did not have phototherapy were recruited from a public school and served as controls. All the children and their parents were interviewed about the use of phototherapy, history of sun exposure and sunscreen use. A dermatologist performed physical examinations on the children and recorded their skin color, eye color, hair color, skin type and the number and size of moles.

Thirty-seven children (63 percent) had moles that were 2 millimeters or larger, and there was an average of 2.09 moles per child. Those who were exposed to phototherapy had significantly more moles of this size than those who did not梐n average of 3.5 vs. 1.45 per child. When the analysis was limited to moles between 2 millimeters and 5 millimeters, the association was stronger. "Lentigo simplex [moles smaller than 2 millimeters in diameter] may represent more recent nevi, whereas those nevi due to early events should be larger," the authors write. "Nevi larger than 5 millimeters probably are congenital nevi and are most probably associated with genetic predisposition." These associations did not change when other risk factors for the frequency of moles, including skin type and light hair, were considered. Sun exposure, particularly during vacations, was also associated with the number of moles of all sizes, and light hair color was correlated with the number of moles smaller than 2 millimeters.

The study did not examine whether phototherapy increases the risk for melanoma in adults, and it is possible that the small difference in the number of moles between the two groups would not change their risk of developing cancer. However, further study could help illuminate the association. "Higher numbers of acquired benign nevi are associated with increased risk of melanoma," they conclude. "A detailed evaluation of the factors responsible for the development of nevi in children would be useful to identify high-risk groups to be targeted for prevention. The link between melanoma and phototherapy should be the focus of such a study."

http://www.eurekalert.org/pub_releases/2006-12/jaaj-pfn121406.php

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