Harderian gland tumours in mice.

A survey of the occurrence of harderian gland tumours in Charles River CD-1 mice (Caesarian derived) showed a relatively higher incidence of harderian gland adenomas in males (5%) in comparison with females (2%) among 3302 untreated control mice from two-year carcinogenicity studies. This sex difference did not apply to the incidence of harderian gland carcinomas. Porphyrin pigment was observed in some of the tumours. Metastasis of the harderian gland carcinoma was seen in lymph node and lung, and in one case the thymus and liver was also affected. Vacuolation, due to fat was seen as helpful diagnostic feature.