Response of the mediastinal and thoracic viscera of the dog to intraoperative radiation therapy (IORT)

Journal Article · Sun Mar 01 04:00:00 EST 1987 · Int. J. Radiat. Oncol., Biol. Phys.; (United States)

DOI:https://doi.org/10.1016/0360-3016(87)90011-3· OSTI ID:6519097

Barnes, M; Pass, H; DeLuca, A; Tochner, Z; Potter, D; Terrill, R; Sindelar, W F; Kinsella, T J

IORT may be a potentially useful adjunctive treatment combined with surgery and/or external beam irradiation in treating locally advanced lung and esophageal tumors. To begin investigation of this modality, the tolerance of intact mediastinal structures to IORT was studied using adult American Foxhounds (wt. 25-30 kg). Groups of six animals received IORT to doses of 20, 30, or 40 Gy to two separate intrathoracic ports, using 9 MeV electrons to treat a portion of the collapsed right upper lobe, and 12 MeV electrons to treat the mediastinal structures. A group of three dogs received thoracotomy with sham irradiation. Two dogs from each treatment dose group, as well as one sham-irradiated control, were sacrificed electively at 1, 3, and 12 months following IORT. There were no acute nor late IORT related mortalities. Post-operative weight loss was minimal (average 4.5% of pre-operative weight) for all dogs. Serial esophagrams showed no inflammation or ulceration. No cardiac nor pulmonary changes were noted clinically. At autopsy, the irradiated lung showed evidence of acute pneumonitis at 1 month with progressive fibrosis at 3 months and 1 year. Esophageal reactions were minimal, with only two dogs (one 30 Gy and one 40 Gy) demonstrating histologically confirmed esophagitis at 1 month. Tracheal changes were minimal. Cardiac damage was evident in the right atrial tissues. In several dogs, this cardiac damage ranged from myocardial vascular changes to frank ischemic necrosis noted at 1 and 3 months, and dense fibrosis at 1 year. The phrenic nerves showed normal function, but had evidence of perineural fibrosis. The large vessels demonstrated only mild histologic evidence of irradiation. The results of this large animal study suggest that intact mediastinal structures will tolerate small volume IORT to doses of 20 Gy without significant clinical sequellae. (Abstract Truncated)

• Research Organization: National Cancer Institute, Bethesda, MD
• OSTI ID: 6519097
• Journal Information: Int. J. Radiat. Oncol., Biol. Phys.; (United States), Journal Name: Int. J. Radiat. Oncol., Biol. Phys.; (United States) Vol. 3; ISSN IOBPD
• Country of Publication: United States
• Language: English

Related Subjects

550603* -- Medicine-- External Radiation in Therapy-- (1980-)
560152 -- Radiation Effects on Animals-- Animals
62 RADIOLOGY AND NUCLEAR MEDICINE
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ANIMALS
AORTA
ARTERIES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
BLOOD VESSELS
BODY
CARDIOVASCULAR SYSTEM
DIGESTIVE SYSTEM
DISEASES
DOGS
DOSES
ESOPHAGUS
INJURIES
LUNGS
MAMMALS
MEDICINE
NECROSIS
NEOPLASMS
NUCLEAR MEDICINE
ORGANS
PATHOLOGICAL CHANGES
PNEUMONITIS
RADIATION DOSES
RADIATION EFFECTS
RADIATION INJURIES
RADIOLOGY
RADIOSENSITIVITY
RADIOTHERAPY
RESPIRATORY SYSTEM
SIDE EFFECTS
SURGERY
THERAPY
TRACHEA
VERTEBRATES