Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology
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Multicenter Study
Radiotherapy for early infradiaphragmatic Hodgkin's disease: the Australasian experience.
To review the Australasian results of Stage I and IIA Infradiaphragmatic Hodgkin's Disease (IHD) treated solely by irradiation. ⋯ The rate of control in IHD could perhaps be improved by avoiding involved field irradiation or by aggressive therapy with total nodal irradiation or combined modality chemo-irradiation in Stage II disease. Staging laparotomy does not appear to be indicated.
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Comparative Study
Differential effects of dose rate and superfractionation on survival and cell cycle of V79 cells from spheroid and monolayer culture.
Recent developments concerning brachytherapy suggest conditions for an equivalence between the common continuous low dose rate (CLDR) exposure and pulsed irradiation regimens (PDR), provided that total dose is administered in the same overall time. The respective theoretical considerations have been based solely on the phenomenon of sublethal damage recovery. The present study, therefore, aimed to assess a possible influence of growth state/cell cycle progression when CLDR and different super fractionation protocols are compared. ⋯ For monolayer cells, on the contrary, the scheme of hourly pulses was significantly more effective than the CLDR irradiation. As measured by flow cytometry, this different behaviour could be attributed to the accumulation of cycling cells in the radiosensitive G2/M phase (G2 block) during protracted exposure which was drastically more pronounced for the pulsed scheme compared to the CLDR condition. The observed principle phenomenon of a block to cell cycle progression from high dose rate pulses (at low overall dose rate) may be less expressed in (human) cells having a long G1 period, but if applicable to a clinical situation, an increase of acute effectiveness of a superfractionated brachytherapy protocol has to be considered.