Spontaneous development of pilosebaceous tumors in the Japanese house musk shrew (Suncus murinus).

Cutaneous pilosebaceous tumors developed spontaneously in high incidence in a colony of the Japanese house musk shrew (Suncus murinus) that has been adapted to laboratory breeding. Multiple tumors of this sort developed in the scalp, back, and hip of older animals, with a marked preponderance in males. The co-presence of tumors with a wide variety of histological grading from benign to malignant in a host or in a single tumor mass was a unique feature.