Table 2

Numbers, incidence, and types of primary CNS tumors in all F344 ratsa

Site and histological classificationAll ratsb (n = 540)
SS (n = 90)SF (n = 90)ES (n = 90)EF (n = 90)EC (n = 90)SC (n = 90)
CNS
Total tumors (rats)1 (1)4 (4)20 (20)17 (16)14 (13)4 (4)
CNS tumor incidence (%)1.14.422.217.814.44.4
No. of CNS glial tumors121915134
Brain tumor incidence (%)1.13.318.915.614.43.3
No. of brain tumors131715143
Glial
Oligodendroglioma001130
Astrocytoma10535c3
Mixed glioma00810d50
Ependymoma012000
Nonglial
Meningioma000010
Granular cell tumor021100
Spinal cord incidence (%)01.13.32.201.1
No. of spinal cord tumors013201
Glial
Astrocytoma011001
Mixed glioma002100
Nonglial
Undifferentiated000100
  • a Only tumors of brain and spinal cord are shown. The number of rats/group is 90. Incidence is in percentage; all other entries are numbers of tumors.

  • b All rats had one tumor except where indicated.

  • c One rat with two astrocytomas.

  • d One rat with two mixed gliomas.