Ishihara Y, Matsumoto K, Kawachi S, Saida T
Department of Dermatology, Shinshu University School of Medicine, Nagano, Japan.
Int J Dermatol. 1993 Jan;32(1):44-7. doi: 10.1111/j.1365-4362.1993.tb00963.x.
The nail area is commonly affected by malignant melanoma. The prognosis of malignant melanoma of the nail is poor, because at the time of diagnosis most lesions are in the advanced stage. Correct diagnosis of early lesions could improve the prognosis.
For 3 years, all patients with nail pigmentation at the dermatology clinic were screened for five specific criteria for the diagnosis of early lesions of malignant melanoma. Histologic examination was performed on 10 of 29 lesions.
Five of the 29 lesions were advanced malignant melanoma, easily diagnosed clinically. Two of the remaining 24 lesions fulfilled most of our clinical criteria of early malignant melanoma of the nail apparatus; that is, they appeared as melanonychia striata during adulthood, were wide in breadth measuring 9 and 11 mm, and showed variegated shades of brown. Periungual pigmented macule (Hutchinson's sign) was observed in one of the two cases. Total resection of the lesions was performed, followed by skin grafting.
Histologically, an increased number of atypical melanocytes, mainly arranged as solitary units, were observed only in the epithelia of the nail matrix and of the nail-bed, confirming that these lesions were "ungual" malignant melanoma in situ. Such an early lesion of malignant melanoma of the nail apparatus can be completely cured with conservative excision, and the phalanx of the affected digit can be preserved.
甲床区域常受恶性黑色素瘤影响。甲下恶性黑色素瘤的预后较差，因为在诊断时大多数病变已处于晚期。早期病变的正确诊断可改善预后。
连续3年，对皮肤科门诊所有甲色素沉着患者进行筛查，以确定早期恶性黑色素瘤病变的5项特定诊断标准。对29个病变中的10个进行了组织学检查。
29个病变中有5个为晚期恶性黑色素瘤，临床易于诊断。其余24个病变中有2个符合我们制定的甲床早期恶性黑色素瘤的大多数临床标准；即它们在成年期表现为甲黑线，宽度分别为9毫米和11毫米，颜色呈斑驳的褐色。其中1例观察到甲周色素沉着斑（哈钦森征）。对病变进行了完整切除，随后进行植皮。
组织学检查显示，仅在甲母质和甲床的上皮中观察到非典型黑素细胞数量增加，主要呈单个排列，证实这些病变为原位“甲下”恶性黑色素瘤。这种甲床早期恶性黑色素瘤病变通过保守切除可完全治愈，并可保留患指的指骨。
