Epidermal, hepatocellular and cholangiocellular carcinomas in brown bullheads, Ictalurus nebulosus, from industrially polluted black river, Ohio

Approximately one-third of brown bullheads, I. nebulosus , collected near the mouth of the Black River, a tributary of Lake Erie in north-central Ohio, had neoplasms of skin or liver or both. Occasionally hepatocellular carcinoma occurred centrally in a larger area of cellular alteration. Most numerous were larger glandular areas with variable fibrous stroma consistent with adenofibrosis. However, the margins of some glandular areas consisted of a highly proliferative, locally invasive population of cells with fair to poor duct differentiation. These lesions were considered to be cholangicellular carcinomas. The Black River is polluted with industrial chemicals in the area of the collections.