Magro Cynthia M, Morrison Carl D, Heerema Nyla, Porcu Pierluigi, Sroa Novie, Deng April C
Department of Pathology, The Ohio State University, Columbus, Ohio, USA.
J Am Acad Dermatol. 2006 Sep;55(3):467-77. doi: 10.1016/j.jaad.2006.04.060.
T-cell prolymphocytic leukemia (T-PLL), formerly categorized as T-cell chronic lymphocytic leukemia, is a rare and aggressive hematologic malignancy. Although the skin is characteristically involved, it is not a well-recognized entity in the dermatologic literature.
Six cases of cutaneous T-PLL are presented from a clinical, light microscopic, and phenotypic perspective.
The patient population comprised 2 women and 4 men, with a mean age of 69.8 years. The disease was associated in all with skin involvement with facial preference; edema, purpura, and lesional symmetry were characteristic. The skin biopsies demonstrated a largely non-epidermotropic angiocentric lymphocytic infiltrate with accompanying hemorrhage. The cells showed irregular- to reniform-shaped nuclei with small nucleoli and eosinophilic rims of cytoplasm. Phenotypic studies revealed three prevailing profiles: CD4 dominant in 4, CD8 dominant in one, and co-expression of CD4 and CD8 in one. CD3 loss was seen in one case. All expressed T-cell leukemia 1 (TCL-1) and CD7; cutaneous lymphocyte antigen expression was discernible in a dot-like perinuclear array. All cases tested excluding one expressed TCL-1 and CD52. In two cases tested, T-cell receptor beta rearrangements were observed. Cytogenetic studies demonstrated a paracentromeric chromosome 14 inversion. Polysomy 8 and MYC amplification was seen in one case, manifesting an aggressive clinical course. Four patients died from their disease within 18 months of diagnosis.
Cytogenetic MYC amplification, FISH, and TCR beta studies were conducted on each of 2 cases, respectively, due to limitations of tissue block samples and/or peripheral blood. cMYC translocation studies were conducted on 3 of the 6 cases, again due to limitations imposed by the tissue samples on the cases. The last case was recently diagnosed and, therefore, long-term follow-up is not possible.
T-PLL is a distinctive post-thymic T-cell malignancy with frequent cutaneous tropism. A diagnosis is possible in almost all cases based on characteristic clinical, light microscopic, phenotypic, and cytogenetic features. While a chromosome 14 inversion is highly characteristic, additional inherent cytogenetic differences, such as trisomy 8 with CMYC over-amplification, may account for some case to case variation in clinical course.
T 细胞幼淋巴细胞白血病（T-PLL），以前归类为 T 细胞慢性淋巴细胞白血病，是一种罕见且侵袭性的血液系统恶性肿瘤。尽管皮肤通常会受累，但在皮肤病学文献中它并不是一个广为人知的实体。
从临床、光学显微镜和表型角度介绍 6 例皮肤 T-PLL 病例。
患者群体包括 2 名女性和 4 名男性，平均年龄为 69.8 岁。所有病例均伴有皮肤受累，以面部为主；水肿、紫癜和皮损对称性为其特征。皮肤活检显示主要为非亲表皮性血管中心性淋巴细胞浸润并伴有出血。细胞显示核呈不规则至肾形，有小核仁及嗜酸性细胞质边缘。表型研究揭示了三种主要类型：4 例以 CD4 为主，1 例以 CD8 为主，1 例 CD4 和 CD8 共表达。1 例出现 CD3 缺失。所有病例均表达 T 细胞白血病 1（TCL-1）和 CD7；皮肤淋巴细胞抗原表达在核周呈点状排列。除 1 例未检测外，所有检测病例均表达 TCL-1 和 CD52。在 2 例检测病例中观察到 T 细胞受体β重排。细胞遗传学研究显示 14 号染色体臂间倒位。1 例出现 8 号染色体多体性和 MYC 扩增，临床病程呈侵袭性。4 例患者在诊断后 18 个月内死于该病。
由于组织块样本和/或外周血的限制，分别对 2 例病例进行了细胞遗传学 MYC 扩增、荧光原位杂交（FISH）和 TCRβ研究。同样由于组织样本的限制，对 6 例病例中的 3 例进行了 cMYC 易位研究。最后 1 例为近期诊断，因此无法进行长期随访。
T-PLL 是一种独特的胸腺后 T 细胞恶性肿瘤，常累及皮肤。几乎所有病例根据特征性的临床、光学显微镜、表型和细胞遗传学特征都可作出诊断。虽然 14 号染色体倒位具有高度特征性，但其他内在的细胞遗传学差异，如 8 号染色体三体性伴 CMYC 过度扩增，可能是导致临床病程存在病例间差异的原因。
