Combination of fractionated irradiation with nicotinamide and carbogen in R1H-tumours of the rat and its pulmonary metastases.
OBJECTIVE
The combination of radiotherapy with nicotinamide and carbogen is a promising method to improve treatment outcome. The aim of the present study was to investigate its effect on rat lungs, the R1H-tumour and its pulmonary metastases.


METHODS
Subcutaneous tumours and artificially induced pulmonary metastases of the rhabdomyosarcoma R1H of the rat were treated either with fractionated irradiation alone or in combination with nicotinamide and carbogen. Local metastatic control, net growth delay and lethal lung damage were used as endpoints.


RESULTS
Radiosensitivity of the lungs of WAG/Rij rats increased by a factor of 1.13, while no positive effect of the combined treatment either on subcutaneous R1H-tumours or on pulmonary metastases could be detected. This resulted in a therapeutic loss of 18% (P = 0.003).


CONCLUSIONS
The results indicate that deleterious effects of the combination of radiotherapy with nicotinamide and carbogen cannot be excluded under all circumstances.
Raabe
A
A
Department of Radiotherapy, University of Hamburg, Germany.
Rett
M
M
Krüll
A
A
Beck-Bornholdt
H P
HP
D000818:Animals; D002245:Carbon Dioxide / Q000008:administration & dosage*; D003131:Combined Modality Therapy; D004195:Disease Models, Animal; D019583:Dose Fractionation, Radiation; D004305:Dose-Response Relationship, Drug; D005260:Female; D008168:Lung / Q000187:drug effects / Q000473:pathology / Q000528:radiation effects; D008175:Lung Neoplasms / Q000188:drug therapy / Q000532:radiotherapy* / Q000556:secondary; D009364:Neoplasm Recurrence, Local; D009374:Neoplasms, Experimental; D009536:Niacinamide / Q000008:administration & dosage*; D010100:Oxygen / Q000008:administration & dosage*; D011838:Radiation-Sensitizing Agents / Q000008:administration & dosage*; D051381:Rats; D012208:Rhabdomyosarcoma / Q000188:drug therapy / Q000532:radiotherapy* / Q000556:secondary; D012878:Skin Neoplasms / Q000188:drug therapy / Q000473:pathology / Q000532:radiotherapy*; D016896:Treatment Outcome
D011838:Radiation-Sensitizing Agents; D002245:Carbon Dioxide; D009536:Niacinamide; C011700:carbogen; D010100:Oxygen