Figure 2

Apoptosis and necrosis caused by treatment with ¹⁸F-FDG in mammary tumors in PyMT mice. Apoptotic and necrotic cells were detected with an Apoptag Plus apoptosis detection kit. (a) A treated tumor in a 10-week-old mouse has numerous apoptotic cells present (stained brown) in the center of the tumor. (b) An untreated tumor in a mouse of the same age has an insignificant number of apoptotic cells. (c) Healthy mammary glands of C3H/B6 mice treated with 3 mCi of ¹⁸F-FDG: no apoptotic or necrotic cells are present. (d) A treated tumor in a 22-week-old mouse shows extensive necrotic areas (stained brown–yellow); some apoptotic cells are also seen at the rim of the necrotic area. (e) An untreated tumor in a 22-week-old mouse. (f) An H&E-stained treated tumor in a 22-week-old mouse: heavy infiltration by leukocytes and a loss of coherence of the tumor cells with breaks in the epithelial sheets are observed. (g) An untreated tumor in a mouse of the same age shows solid sheets of tumor cells. Original magnifications: (a–c) × 400; (d–g) × 200.