Experimental Melanoma in Hamsters

Abstract

Melanotic tumours are ranged among the relatively rare tumours found in laboratory animals. The Harding-Passey and Cloudman melanomas in mice currently constitute “classic tumour stock”. Iglesias in 1960 [9] discovered spontaneous melanoma in A × C rats, later, new instances were described in these animals. The intensified use of hamsters in cancer research has brought about the observation that the animal was of great interest in the study of melanogenesis and pigmentary cancerisation. Spontaneous naevo-carcinomata have been observed in golden hamsters by a number of authors; thus Fortner [4] found 3 melanotic tumours in a total of 301 hamsters; Fortner and Allen [5] found 10 melanomata in 523 hamsters (i. e. almost 2 per cent). Spontaneous melanoma in this animal was also described by Greene [8],and by Bomirski et al. [1]. We have described the pathologico-anatomic aspect and biology of a melanoma found in a golden hamster. The animal had been irradiated (X-rays, general irradiation); we were unable to establish whether the irradiation had played a favouring role [16]. We have collected five new cases of melanoma in irradiated hamsters since.