PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “RADIOTHERAPY DOSAGE”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources
PubMed1988

[Adenoid cystic carcinomas of the head and neck. Results of treatment with high-dosage radiotherapy].

Different opinions exist about the role of radiotherapy in the treatment of adenoid cystic carcinoma of the head and neck. In this paper the results of 14 patients with high-dosage irradiation are reported. Radiotherapy with local curative intent was performed in all patients. 10/14 patients were irradiated post-operatively. 4/14 patients received radiation therapy alone. By percutaneous irradiation (n = 13) focal doses of 80 Gy were applied, by interstitial irradiation (n = 1) 70 Gy. Despite the less favourable patient group - 8/14 patients had either a T3- or T4-tumour; 5/14 patients were referred because of recurrent disease - local tumour control could be achieved in all cases after a mean observation time of 3.5 years. Together with newer reports of literature we consider adenoid cystic carcinomas of salivary gland origin as locally curable by postoperative high-dosage radiotherapy.

Adult↗
PubMed1988

[Optimization of the radiotherapy dosage in vertebral metastases].

The authors describe the radiation therapy treatment planning used in the Department of Radiotherapy of Mauriziano Hospital, Turin, to treat bone metastases from various tumors. The study population consisted of 33 patients with vertebral metastases. Treatment with a 60Co therapy unit was performed following either a conventional or a concentrated schedule. The association of a direct posterior field and a rotational technique with the same center and swing angle varying from 120 degrees and 150 degrees is described. The dose percentage given with the two techniques, the field width and the arching angle variables related to depth and volume of the target are discussed. We present some examples elaborated with a dedicated computer by calculating the integral area dose to the whole body and to the target, towards the best treatment planning for every kind of treatment proposed in two groups of six patients with vertebral and sacral metastases. The technique allows a homogeneous dose distribution to the target, thus reducing the area dose to the whole body, which means good radiotherapeutic results.

Cobalt Radioisotopes↗
PubMed1993

[Radiotherapy in adults with localized supradiaphragmatic stages CS I/II of Hodgkin's disease. 2. The special aspects of radiotherapy: dosage, fractionation, focal volumes, risks, conclusions].

For patients with Morbus Hodgkin and CS I/II of the low risk group and primary radiotherapy recommended treatment fields are: regional field for isolated high cervical involvement, mantle field for isolated mediastinal involvement and extended mantle field for the other patients. Omission of the infradiaphragmatic irradiation volume for PS I/II may be regarded as an advantage, which must be compared with the risk of a staging laparotomy, whereas the low risk of undertreatment of a small part of patients with CS I/II PS III probably does not outweigh the risk of the laparotomy. Equal efficacy of chemotherapy alone for these patients has not been proven sufficiently and important questions concerning long-term risks are unanswered. Ongoing studies will show, whether combinations with reduced chemotherapy or other types of chemotherapy and local radiotherapy are superior. Details of the mantle field borders and blocking are described. In most patients with adjuvant radiotherapy after complete remission after chemotherapy, the recommended target volume includes only the regions with proven involvement before chemotherapy. Details of the mediastinal treatment volume for patients with adjuvant radiotherapy after chemotherapy for bulky mediastinal disease are given. According to some recent analysis of a large body of dose-effect data, the recommended target doses in primary irradiation are between 36 and 40 Gy for regions with proven involvement and between 30 and 36 Gy for electively treated regions. The recommended target dose per fraction is between 1.5 and 1.8 Gy and less than 2 Gy in various critical tissues. According to the recent recommendations, the maximal total doses in mantle field radiotherapy to the spinal cord should be 38 Gy for radiotherapy alone and 36 Gy for radiotherapy combined with chemotherapy. The maximal total dose to the whole heart should be 15 Gy and for the other parts between 30 and 35 Gy. After chemotherapy with MOPP oder MOPP-like regimes, there is a cumulative risk of leukaemia between 2.2 and 11.9%. After radiotherapy alone, there is only a very low risk of leukaemia after radiotherapy and chemotherapy to the risk after chemotherapy. Most long-term studies show an increased risk of solid second malignancies associated with radiotherapy with a relative risk of approximately two. In the analyzed studies, the cumulative risk of solid second malignancy after seven to 15 years is between 7 and 11.2% after radiotherapy, between 7 and 11.7% after chemotherapy and between 7 and 11.7% after radiotherapy and chemotherapy.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1979

The direct use of CT numbers in radiotherapy dosage calculations for inhomogeneous media.

Techniques by which the quantitative anatomical data inherent in a CT scan can be directly used in treatment planning are described. The correction algorithms used in the RAD-8 system, based on an effective path length, have been extended to a pixel-by-pixel approach. By calibrating the X-ray transmission CT scanner in terms of electron densities (electron cm-3) inhomogeneity corrections may be made automatically.

Humans↗
PubMed2001

[Mucoepidermoid carcinoma of the salivary glands after high dosage radiotherapy].

BACKGROUND: High-dose radioiodine therapy following total thyroidectomy is standard for patients suffering from differentiated thyroid carcinoma and contributes significantly to their favourable prognosis. Due to active iodine accumulation, high focal radiation doses are received by the salivary glands. PATIENTS/RESULT: Report on two patients, who received multiple high-dose radioiodine treatments because of a differentiated metastatic thyroid carcinoma. A few years later, they developed a mucoepidermoid carcinoma of the salivary glands. Due to the high cumulative radiation dose, radiation-induced secondary malignancies following radiation-induced sialadenitis appears likely, although no causal connection could be proven. CONCLUSION: Consistent protection of the salivary glands during radioiodine therapy as well as the follow-up of the many long-term survivors of differentiated thyroid carcinomas is desirable to further lower the salivary gland-related side effects and to detect secondary malignancies as early as possible.

Adult↗