生物谷报道：美国一项疾病研究显示，一种罕见而神秘的癌症——皮肤T细胞淋巴瘤正在美国悄然增加。
这项由布朗大学Warren Alpert医学院和普罗维登斯医学中心的研究人员进行的研究发现，在1973年到2002年间诊断出的新的皮肤T细胞淋巴瘤病例共有4783个。而且新病例的数量在每个十年里都有明显的增长，增长速度超过3倍。
这项研究的负责人Martin Weinstock博士表示，这种疾病在相当于一代人的时间里已经明显变得常见了。目前还不知道造成这种变化的原因是什么，但是数据本身则为人们敲响了警钟。
皮肤T细胞淋巴瘤是由于皮肤中一种类型的白细胞生长失控所导致的。这种癌症转移很慢，刚开始往往以皮疹的形式出现。目前，还不清楚这种类型癌症的发病机理。尽管有一些治疗药物，但目前还无法治愈这种疾病。
这项研究由Weinstock指导的二年级研究生Vincent Criscione所完成，他也是发表在7月的Archives of Dermatology杂志上论文的主要作者。
Criscione利用来自美国癌症研究所的Surveillance、Epidemiology and End Results(SEER)计划的数据描述了皮肤T细胞淋巴瘤的变化趋势：
1．发生率在30年里稳定攀升
2．被确诊的男性患者是女性的两倍
3．黑人比白人更可能患上这种疾病。
4．这种癌症多发生在老年人中，但也发生其他年龄段的人群中
5．生活在医疗条件优越的地区的人以及社会经济地位较高的人更可能患这种病。
原发性皮肤T细胞淋巴瘤(cutaneous T cell lymphoma，CTCL)曾称为蕈样肉芽肿（granuloma fungoid），是T淋巴细胞（特别是T辅助细胞亚群）起源的一种皮肤原发淋巴瘤。呈慢性进行性经过，可累及淋巴结和内脏。目前病因尚不明，可能与遗传、感染和环境因素可能与本病发生发展有关。
其临床表现可分为红斑期、斑块期和肿瘤期，但各期表现可重叠。红斑期，皮损无特异性，类似于慢性单纯性苔藓样变、湿疹、慢性接触性皮炎、脂溢性皮炎、特应性皮炎、副银屑病等，多伴有剧烈顽固性瘙痒。
在斑块期，可由红斑期发展而来或直接在正常皮肤上发生。皮损呈形态不规则、界限清楚、略高起的浸润性斑块，颜色暗红至紫色，可自行消退，亦可融合形成大的斑块，边缘呈环状、弓形或匍行性，颜面受累时褶皱加深形成“狮面”。
肿瘤期里，皮损呈褐红色隆起性结节，大小、形状各异，易早期破溃，形成深在性卵圆形溃疡，基底被覆坏死性灰白色物质，溃疡边缘卷曲；继发感染可伴疼痛及恶臭。患者常在数年内死亡。偶亦见开始即表现为肿瘤而未经红斑期或斑块期皮损者，称暴发型皮肤T细胞淋巴瘤，预后差。除皮肤外，淋巴结最常受累，其他依次为脾、肺、肝、骨髓、肾脏、舌或会厌、心脏、胰腺和甲状腺，内脏受累往往在尸检时才能发现。
在欧美地区，皮肤癌是一种广受关注的疾病。在生物实验室里，紫外灯的使用非常普遍，但这种灯光对人皮肤的损害是大的，因此从事这类研究的科研人员和学生应该尽可能地避免皮肤直接照射紫外光，以避免紫外光诱导发生的皮肤病变。
原始出处:
Archives of Dermatology
Vol. 143 No. 7, July 2007
Incidence of Cutaneous T-Cell Lymphoma in the United States, 1973-2002
Vincent D. Criscione, AB; Martin A. Weinstock, MD, PhD
Arch Dermatol. 2007;143:854-859.
Objective To describe incidence trends for cutaneous T-cell lymphoma (CTCL) in the United States.
Design Population-based study.
Setting Data were obtained from 13 population-based cancer registries of the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute from 1973 through 2002.
Participants A total of 4783 cases of CTCL were identified for the period 1973 through 2002.
Main Outcome Measure Diagnosis of CTCL.
Results The overall annual age-adjusted incidence of CTCL was 6.4 per million persons. Annual incidence increased by 2.9 x 10–6 per decade over the study period. Incidence was higher among blacks (9.0 x 10–6) than among whites (6.1 x 10–6) and was higher among men (8.7 x 10–6) than among women (4.6 x 10–6). The racial differences in incidence decreased with age, while the sex differences increased with age and decreased over time. Substantial geographic variation in incidence was found. Incidence was correlated with high physician density, high family income, high percentage of population with a bachelor's degree or higher, and high home values. Changes in International Classification of Diseases for Oncology (ICD-O) morphologic definitions have resulted in the redistribution of the cases of CTCL among specific subclassifications.
Conclusions The continued rise in incidence of CTCL is substantial, and the cause of this increase is unknown. The racial, ethnic, sex, and geographic differences in incidence may be of etiologic importance. Changes in ICD-O definitions have made it difficult to evaluate incidence trends for subclassifications of CTCL such as mycosis fungoides. In addition, these changes resulted in the creation of ambiguous histologic codes, which may have caused coding errors. These errors along with the lack of independent verification are limitations of our study. An epidemiological investigation using population-based data is important to better understand this disorder.
Author Affiliations: Dermatoepidemiology Unit, VA Medical Center, Department of Dermatology, Rhode Island Hospital, and Departments of Dermatology and Community Health, Brown University, Providence, Rhode Island.
