PDF(Pubmed)
Abstract：
Melanocytic skin tumours have been rarely described in pet rabbits, and exposure to UV light in sparsely haired areas has been hypothesised to play a cancerogenic role. Here, we describe a case of cutaneous malignant melanoma arising from the skin of the scrotum in an 8-year-old male wild rabbit, with testicular metastases as an unusual metastatic site for melanoma reported in humans to date. The tumour was nearly 5 cm in size, firm, and highly pigmented, with multifocal superficial ulcerations and large areas of intratumoural necrosis. The adjacent testis was 1.5 cm, multinodular, and black, obscuring tissue morphology. Histologically, the dermis was expanded by an infiltrative, densely cellular neoplasm composed of nests and sheets of polygonal to spindle neoplastic melanocytes, supported by scant fibrovascular stroma. Neoplastic cells showed intermediate N/C ratio, moderate basophilic cytoplasm, often obscured by abundant brownish granular pigment, and eccentric nuclei with prominent nucleoli. Cellular pleomorphism and nuclear atypia were severe, and high mitotic activity was observed. Diffuse dermal lymphovascular invasion was also observed. The testis was delimited by a thin tunica albuginea, and the parenchyma was largely obscured in its morphology by densely packed neoplastic cells. Seminiferous tubules, lined with a thin basement membrane and containing neoplastic and scattered spermatogenic cells, were occasionally observed. Neoplastic cells within the skin and the testis were positive for HMB-45, Melan-A, and S-100. The growing popularity of rabbits as pets allows for a greater ability to accumulate data on the spontaneous occurrence of tumours in these animals. Furthermore, descriptions of the biological aspects of spontaneously occurring tumours may serve to improve current knowledge in animal species and humans in which the same neoplasm may occur.
摘要：
在宠物兔中很少描述黑素细胞性皮肤肿瘤，并且假设在稀疏的头发区域暴露于紫外线可以起到致癌作用。这里,我们描述了一个由8岁雄性野兔阴囊皮肤引起的皮肤恶性黑色素瘤的病例，睾丸转移是迄今为止人类报道的黑色素瘤的不寻常转移部位。肿瘤大小接近5厘米，公司，色素沉着，多灶性浅表溃疡和大面积肿瘤内坏死。相邻睾丸1.5厘米，多节点，黑色，模糊组织形态。组织学上,真皮被渗透剂扩张，密集的细胞肿瘤由巢和多边形到纺锤形肿瘤黑素细胞片组成，由很少的纤维血管基质支持。肿瘤细胞显示中等N/C比，中度嗜碱性细胞质，通常被丰富的褐色颗粒状色素所模糊，和具有突出核仁的偏心核。细胞多态性和核异型性严重，并观察到高有丝分裂活性。还观察到弥漫性真皮淋巴管浸润。睾丸由一个薄薄的白膜界定，薄壁组织的形态在很大程度上被密集堆积的肿瘤细胞所掩盖。生精小管,衬有薄的基底膜，含有肿瘤和分散的生精细胞，偶尔被观察到。皮肤和睾丸内的肿瘤细胞对HMB-45，Melan-A，S-100兔子作为宠物的日益普及允许更大的能力来积累关于这些动物中肿瘤自发发生的数据。此外，对自发发生的肿瘤的生物学方面的描述可能有助于提高可能发生相同肿瘤的动物物种和人类的最新知识。
