Complications of radiation therapy

The skeletal effects of radiation are dependent upon many variables, but the pathologic features are consistent. Radiation may cause immediate or delayed cell death, cellular injury with recovery, arrest of cellular division, or abnormal repair with neoplasia. Radiation necrosis and radiation-induced neoplasm still occur despite the use of supervoltage therapy. Complications of radiotherapy are well known and have led to more judicious use of this therapeutic modality. With few exceptions, benign bone tumors are no longer treated with irradiation. Radiation necrosis may be difficult to differentiate from sarcoma arising in irradiated bone. They both occur within the field of irradiation. Radiation necrosis often has a long latent period which is, of course, the rule in radiation-induced neoplasia. A soft tissue mass favors the diagnosis of neoplasia, while its absence suggests radiation necrosis. Lack of pain favors necrosis. Calcification may occur in radiation necrosis and does not indicate neoplasia. A lack of progression on serial roentgenograms also favors radiation necrosis.     

Complications of megavitamin therapy

A patient with pancytopenia, severe sensory neuropathy, and a six-year history of excessive vitamin intake showed portal hypertension on evaluation. A liver biopsy revealed hypervitaminosis A. His sensory findings were characteristic of a recently described syndrome of sensory neuropathy secondary to megadoses of vitamin B6. The patient's neuropathy has improved, but his pancytopenia has persisted. The practice of ingesting large doses of vitamins is increasing in a considerable segment of our population. Many claims of therapeutic benefit have been made, but few have been demonstrated in controlled clinical trials. Although there are indications for the use of large dosages of certain vitamins, they are rare. Physicians should be aware of the toxicities of megavitamin therapy.     

Complications associated with barbiturate therapy

Fifty-six patients with elevated intracranial pressure caused by cerebrovascular accident, head injury, etc., were the subjects of this study. They were divided into three groups: low dose barbiturate therapy (15 patients), high dose barbiturate therapy (24 patients), and control group (17 patients). Barbiturate therapy was instituted using thiamylal, and the complications caused by barbiturate therapy were recorded. In the control group, complications occurred in the liver of two patients, but there were no renal or pulmonary complications. Pulmonary, renal, and hepatic complications were common in the barbiturate groups. Complications in the high dose therapy group were significantly more common than in the control group. Opportunistic infections occurred in ten patients, with seven patients having pneumonia. Only one patient, with pneumonia, was seen in the control group. The deaths of three patients were influenced by complications associated with barbiturate therapy, while the single death in the control group was not associated with the complication of barbiturate therapy.     

Complications of photodynamic therapy in gastrointestinal disease

The primary complications of photodynamic therapy of the esophagus include cutaneous photosensitivity and esophageal strictures. Atrial fibrillation and pleural effusion have been reported but appear to be rare or not clinically significant. Cutaneous photosensitivity can be minimized if the adequate precautions are taken to protect patients from sunlight exposure. Stricture formation may be decreased by proper dosimetry and avoiding multiple overlapping light applications.     

Complications after megavoltage therapy of Hodgkin's disease.

56 patients with Hodgkin's disease treated with large field megavolt irradiation are presented. Complications in the parenchymal organs were few, although patients developed an appreciable grade of pulmonary radiofibrosis, two patients had a myocardial infarction and one patient thrombosis of the portal veins. Depression of the bone marrow frequently interfered with the radiation treatment. In five cases radiotherapy had to be discontinued. In three cases bone marrow depression persisted to the time of death. The total mode treatment was often to be discontinued and the treatment with cytostatics was started. The extended and total node treatment for Hodgkin's disease must be planned to spare as much of the bone marrow as possible.     

儿童恶性肿瘤放射治疗并发症的研究进展

儿童恶性肿瘤治疗后的长期生存者是各医疗保健专家公认的患病高风险人口,对肿瘤的各种治疗手段都会不同程度的影响到儿童的生长和发育。放疗及化疗后的幸存者,将经历慢性或迟发性身体健康问题。成长中的儿童受放疗影响尤其敏感,受照野内的器官和组织、放射源的选择、分割方式、累积照射剂量和不同的受照年龄都会对放疗反应的轻重有明显的影响。