III. Pathological Changes in the Bladder Following Irradiation

The gross and microscopic changes found in the bladder after irradiation have been described by a number of workers and have been investigated by experiments on animals. Shields Warren (1942) has stated that the vesical epithelium is moderately resistant to ionizing radiation and is able to with-stand up to 8,400 r in divided doses. He recognises three stages in the radiation reaction: (1) primary erythema, appearing in 24 hours or less, (2) secondary erythema, appearing in three to four weeks, and (3) a late reaction, rarely becoming manifest in less than one year. The early stages are characterised histologically by oedema, hyperaemia and epithelial desquamation. In the late stages there may be ulcers encrusted with urinary salts. The connective-tissue undergoes hyalinisation, the blood-vessel walls are thickened and fibrosis may spread into the muscle layers. Giant and bizarre fibroblasts may be seen. According to Hueper, Fisher, Carvajel-Forero and Thompson (1942) the late reactions may make their appearance at any time between three months and ten years. They described induration of the bladder wall, reduction of luminal capacity and encrustation of the mucosa with salts (the “Panzerblase” of German authors). The ulcers were sharply out-lined; they were often surrounded by bullous oedema and radiating, tortuous, ectatic blood vessels. On healing they left greyish-white avascular scars. In other cases, these authors found raspberry-like granulations, situated in an extremely hyperaemic mucosa. They stressed the resemblance that such ulcers may bear to cancerous or tuberculous lesions.