Document vB4983JRbnNZ23m1EgYxKm6OY

AROCLOR 1260: Meeting at NCI, January 31, 1975 The purpose of this meeting was to review sections of liver tissue from Dr. Kimbrough's 2-year study In which female rats were fed 100 ppm of AROCLOR 1260. Drs. Kimbrough and Squire had studied and classified the findings. Dr. Levitt, either a visiting fellow or a post doctoral trainee did not participate to any great extent. He was mentioned as having a good knowledge of liver. Dr. Richter had viewed the slides from our 2-year study in which rats of both sexes had been fed 100 ppm, 10 ppm or 1 ppm of AROCLOR 1260. Subsequently, he and Dr. Gordon reviewed sections of liver from all animals in this study. Three conclusions can be drawn. 1. In our earlier study, the severity of liver lesions was greater in females them in males. 2. To a large extent, substantially the same type of lesions 1 were observed In both studies exqspX-thaf the lesions seemed to be more advanced in Kimbrough's study. Although [ there was some variation in terminoiog.vT~CKe findings ^ were reasonably close.----` ........ 3. Theye were definite liver adenocarcinomas in Kimbrough's study. Dr. Richter expressed^thg^ylew -ia-ter that 2 ani mals in our study approached_the_typeof leBlon Kim brough haafT^beWed, but there was agreement by~Drs. Gor don and"RlchtST "that Dr. Kimbrough'B rats had developed a lesion which they~had not observed in our earlier study with AR6CL0in260. r----- ------------- ----- If. Drs. Gordon or Richter feel that I have not summarized this meeting correctly, or if they desire to amend or expand my remarks, I invite them to let me know. HONS 045zas