The prevalence and severity of late effects in normal rat duodenum following intraoperative irradiation

• Published in: International journal of radiation oncology, biology, physics Vol. 18; no. 4; pp. 841 - 848
• Main Authors: Poulakos, Lawrence, Elwell, James H., Osborne, James W., Urdaneta, Luis F., Hauer-Jensen, Martin, Vigliotti, Antonio P., Hussey, David H., Summers, Robert W.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.04.1990; Elsevier
• Subjects: Animals; Biological and medical sciences; Diseases of the digestive system; Dose-Response Relationship, Radiation; Duodenum; Duodenum - radiation effects; Intraoperative irradiation; Intraoperative Period; Male; Medical sciences; Radiation Injuries, Experimental - mortality; Radiation injury; Radiotherapy. Instrumental treatment. Physiotherapy. Reeducation. Rehabilitation, orthophony, crenotherapy. Diet therapy and various other treatments (general aspects); Rat; Rats; Rats, Inbred Strains; Survival Rate; Time Factors; Radiation injury; Intraoperative irradiation; Duodenum; Rat; Carcinoma; Rodentia; Intraoperative; Malignant tumor; Radiotherapy; Vertebrata; Mammalia; Treatment; Animal; Digestive diseases; Complication; Tumor; Pancreas; Pancreatic disease
• ISSN: 0360-3016; 1879-355X
• DOI: 10.1016/0360-3016(90)90406-A

In humans, a portion of the duodenum is often at risk for radiation-induced complications following intraoperative radiation therapy for pancreatic carcinoma. To determine experimentally the prevalence and severity of late effects in the normal mammalian duodenum, 190 rats received single doses of 0, 15, 20, 25, 30, or 40 Gy orthovoltage X rays to temporarily exteriorized 3 cm circumferential segments of duodenum. The animals were killed 2, 6, 8, or 10 months later. Actuarial survival, change in body weight, and a radiation injury score based on eight histopathologic alterations were used as endpoints. Epithelial atypia, intestinal wall fibrosis, serosal thickening, and vascular sclerosis were the dominant histopathologic alterations at all dose levels throughout the 10-month observation period. The prevalence and severity of histologic radiation injury showed sigmoidal dose-response relationships with the plateaus starting at 20 Gy. Doses of 20 Gy or greater also resulted in a substantial loss of body weight and a high level of early deaths (20–80 days). All endpoints indicate that intraoperative doses of 20 Gy or greater are associated with unacceptable risks of late and irreversible complications.