Development of malignant lymphoma in some of the young rats suckled by mothers receiving methylcholanthrene by stomach tube only during the lactation period.Preliminary report

Abstract

vv E HAVE recently reported9 that the gastric instillation of methylcholanthrene is followed by the development, in very high incidence,. of adenocarcinoma of the breast in female Wistar rats, with the appearance only rarely of a malignant tumor elsewhere in the body. These results raised certain questions: Did the breast cancers occur because of a preferential concentration of the absorbed carcinogen in breast tissue? Could the chemical carcinogen be excreted in the milk and, as a result, might malignancy be induced in the offspring suckled during a period when such carcinogens appear in the milk? T h e experiments reported herein were undertaken in an attempt to answer these questions.