For exposure-response array data display purposes, the following results were coded (control and no effect findings were coded as "0", treatment-related increases were coded as "1", and treatment-related decreases were coded as "-1".

"Overall tumor incidence was comparable between control and exposed groups. In fact, the only significant neoplastic change was a finding of five (5.6%) pancreatic islet cell adenomas in the 20,000 ppm exposure group female rats.... Also of interest were findings of one undifferentiated sarcoma and one adenoma in the posterior region of the nasal cavity in two male rats; one carcinoid-like neoplasm in the midlateral wall of the nasal cavity in a male rat; and one papilloma in the posterior region of the nasal cavity in a female rat, all from the 10,000 ppm exposure level group. In addition, one early carcinoma was seen in the posterior region of the nasal cavity of one male rat in the 2000 ppm exposure level group. No tumors were seen in the nasal cavities of any control or 20,000 ppm exposure level group rats."

"There were no macroscopic postmortem observations which could be attributed to effects of the FC-113 exposures. Also, there were no significant microscopic observations of non-neoplastic changes that appeared related to the exposures to FC-113. The distribution and type of findings were similar in the control and FC-113-exposed groups.

From Discussion section: "A few morphologically unique tumors were also seen in the nasal passages of one low- and four mid-level exposure group rats but were not believed to be treatment related. The fact that no two tumors were the same cell type, there was no dose-related trend (p < 0.5), and the absence of any other histopathologic changes (metaplasia, hyperplasia, etc.) in the nasal turbinates at any exposure level argue against a compound-related effect. Although it is true that spontaneous nasal tumors in rats are rare, one such tumor has been seen in a control group in each of three chronic studies conducted over the last 5 years at this laboratory."

Sample size unclear; entered 90 based on initial sample size of 100/sex and 10/sex were sacrificed at 12 months. "Approximately 24 months after initiation of the study, all surviving rats were terminated and necropsied. All rats found dead or terminated in extremis were also necropsied."

Male Crl:CDBR Rats