20 research outputs found

    14. Search for improvement of the therapeutic ratio in radiotherapy for non-small cell lung cancer (NSCLC)

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    There are several approaches under investigation in view of improvement of the therapeutic ratio of NSCLC radiotherapy in our Department:1/ Dose escalation above 70 Gy using conformal radiotherapy techniques, 2/ accelerated radiotherapy with or without induction chemotherapy addressed to III stage tumours, 3/ conformal postoperative radiotherapy to total minimum dose in PTV of 50 Gy addressed to completely resected III stage tumours.Ad 1/ From XI 1998 to XI 2000 43 patients were included in dose escalation study. Doses from 70 to 74 Gy were delivered. Apart from one toxic death, due to radiation pneumonitis, toxicity was acceptable. Since 1999 for NO patients the study of omission of elective irradiation is conducted. By the time being 10 patients were irradiated with omission of elective fields. There was no relapse in non-treated “elective areas”. The actuarial 1-, 2- and 3-year survival were respectively 84-, 64-, and 42%. There were 14 local relapses in 19 progressions observed in the entire group. In spite of encouraging results a high level of local relapses shows the limits of moderate dose escalation using conformal techniques and conventional fractionation in improvement of local control of NSCLC.Ad 2/ From III 1999 two different accelerated radiation therapy schedules are investigated for III stage tumours. Forty patients were enrolled in the study: 26 were irradiated according to accelerated hyperfractionated radiotherapy (57 Gy in 40 fractions [first week: elective fields −1.2 Gy × 2 per day, 3 remaining weeks 1.8 Gy to elective fields and 1.2 Gy boost to tumour] during 26 days), 14 were irradiated according to accelerated conformal radiotherapy with concurrent boost (56.7 Gy in 21 fractions and 26 days: all treatment was conformally planned and delivered: 1,9 Gy per fraction to the limited elective field and 0.8 Gy as a concurrent boost to the GTV). There was no difference on compliance with treatment plan, toxicity and response rate (80- and 72%) in the both investigated groups.Ad 3/ From I 1999 eleven patients were enrolled in the phase II study of postoperative conformal radiotherapy of the region of the highest probability of microscopic invasion by the disease to the minimum dose of 50 Gy in PTV. The study is conducted in view of the future design of randomised study addressing question of the value of postoperative radiotherapy using modern techniques in management of NSCLC

    40. Comparison of two accelerated radiotherapy regimens in management of locally advanced non-small cell lung cancer (NSCLC) – hyper-fractionated conventional accelerated radiotherapy (RAHIP) and accelerated conformal radiotherapy with concurrent boost (RT-BOOST)

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    BackgroundRepopulation during radiation therapy may compromise the results of the treatment of NSCLC. In spite of the data showing an improvement of therapeutic ratio with shortening of the total treatment time, there is no univoa.ue way of doing, it. Current study was conducted to compare two different regimens of accelerated radiotherapy.Material/MethodsFrom March 1999 to November 2000 forty patients with stage III NSCLC were included. Twenty-eight pts. (70%) received 3–4 cycles of induction chemotherapy (cis-platinum, vepeside). Twenty-six p. were treated according to RAHIP schema, 14 pts. according to RT-BOOST schedule. RAHIP consisted in radiotherapy twice-daily delivered: first week: 2×1,20 Gy “elective fields”, the remaining three weeks 1,80 Gy “elective fields” and 1,20 Gy boost on involved areas by oblique fields. Total dose was 57 Gy. Conventional treatment techniques were employed. RT-BOOST technique was conformally planned and delivered, total dose was 56,7 Gy in 21 fractions (per fraction: 1,9 Gy to limited elective areas and concurrent boost of 0,8 Gy to the GTV) and 26 days.ResultsWith a follow-up period ranging from 1 to 19 months, there is no difference in the compliance with the treatment-plan, treatment tolerance and response rate in the two analysed groups. In all but two patients treatment plan was realised. In RT-BOOST group treatment was discontinued in one patient, because of prolonged III° EORTC/RTOG oesophageal toxicity. In RAHIP group in one patient treatment was prolonged by 10 days because of pneumonitis (II° lung toxicity). One case of III° oesophageal toxicity was observed in each group. There was no increase in toxicity among patients receiving chemotherapy before radiotherapy. The response rate was similar in both analysed groups (RAHIP: 73% PR, 7,5%, CR; RT-BOOST: 65% PR, 7% CR). Estimated by Kaplan-Meier actuarial one-year survival rate method was 66% and actuarial one-year progression free-survival rate was 58% for the entire group.ConclusionsPreliminary results of accelerated radiotherapy for locally advanced NSCLC seem promising. Additionally a good compliance with the treatment in both groups allows to work out a phase III study dealing with this problem

    14. Search for improvement of the therapeutic ratio in radiotherapy for non-small cell lung cancer (NSCLC)

    Get PDF
    There are several approaches under investigation in view of improvement of the therapeutic ratio of NSCLC radiotherapy in our Department:1/ Dose escalation above 70 Gy using conformal radiotherapy techniques, 2/ accelerated radiotherapy with or without induction chemotherapy addressed to III stage tumours, 3/ conformal postoperative radiotherapy to total minimum dose in PTV of 50 Gy addressed to completely resected III stage tumours.Ad 1/ From XI 1998 to XI 2000 43 patients were included in dose escalation study. Doses from 70 to 74 Gy were delivered. Apart from one toxic death, due to radiation pneumonitis, toxicity was acceptable. Since 1999 for NO patients the study of omission of elective irradiation is conducted. By the time being 10 patients were irradiated with omission of elective fields. There was no relapse in non-treated “elective areas”. The actuarial 1-, 2- and 3-year survival were respectively 84-, 64-, and 42%. There were 14 local relapses in 19 progressions observed in the entire group. In spite of encouraging results a high level of local relapses shows the limits of moderate dose escalation using conformal techniques and conventional fractionation in improvement of local control of NSCLC.Ad 2/ From III 1999 two different accelerated radiation therapy schedules are investigated for III stage tumours. Forty patients were enrolled in the study: 26 were irradiated according to accelerated hyperfractionated radiotherapy (57 Gy in 40 fractions [first week: elective fields −1.2 Gy × 2 per day, 3 remaining weeks 1.8 Gy to elective fields and 1.2 Gy boost to tumour] during 26 days), 14 were irradiated according to accelerated conformal radiotherapy with concurrent boost (56.7 Gy in 21 fractions and 26 days: all treatment was conformally planned and delivered: 1,9 Gy per fraction to the limited elective field and 0.8 Gy as a concurrent boost to the GTV). There was no difference on compliance with treatment plan, toxicity and response rate (80- and 72%) in the both investigated groups.Ad 3/ From I 1999 eleven patients were enrolled in the phase II study of postoperative conformal radiotherapy of the region of the highest probability of microscopic invasion by the disease to the minimum dose of 50 Gy in PTV. The study is conducted in view of the future design of randomised study addressing question of the value of postoperative radiotherapy using modern techniques in management of NSCLC

    Ligninolytic activity of Heterobasidion parviporum isolates in cultivation on Norway spruce wood

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    The aim of this preliminary study was to assess the activity of laccase, diverse peroxidases as well as the level of micromolecular compounds in Heterobasidion parviporum isolates grown on pieces of Norway spruce wood (sapwood and heartwood) during 50 days of incubation under the laboratory conditions. H. parviporum isolates secreted extracellular enzymes: laccase, manganese peroxidase (MnP), lignin peroxidase (LiP) and versatile peroxidase (VP). Hydroxy− and methoxyphenols were also released during this process. The above−mentioned enzymes showed low activity in mycelium grown on both sapwood and heartwood. The activity of laccase ranged from 0 to 0.513 mU/mg protein on sapwood, and from 0 to 0.106 mU/mg protein – on heartwood. MnP activity of H. parviporum isolates ranged from 0.024 to 0.667 mU/mg protein on sapwood, and from 0.038 to 1.585 mU/mg protein – on heartwood. LiP activity was small and ranged from 0 to 1.281 mU/mg protein on sapwood, and from 0.013 to 0.166 mU/mg protein – on heartwood. Activity of VP oxidizing manganese ions was low. It ranged from 0 to 3.063 mU/mg protein on sapwood, and from 0.059 to 3.054 mU/mg protein – on heartwood. The activity of VP oxidizing guaiacol ranged from 0.006 to 1.490 mU/mg protein on sapwood and from 0.038 to 1.147 mU/mg protein – on heartwood. The hydroxyphenols produced by H. parviporum isolates ranged from 15.037 to 110.149 mg of protocatechuic acid/ml on sapwood, and from 11.236 to 27.220 mg of protocatechuic acid/ml – on heartwood. Methoxyphenols produced by H. parviporum isolates ranged from 3.393 to 24.253 mg of vanillic acid/ml on sapwood, and from 4.955 to 12.005 mg of vanillic acid/ml – on heartwood

    Scots pine and Norway spruce seedlings susceptibility to infection by Armillaria ostoyae under increased CO2 concentration

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    Comparative cultivation experiment was carried out in the greenhouse to verify the assumption that increased air CO2 concentration (up to 1000 ppm) stimulates the infection intensity and mortality rate of Scots pine and Norway spruce seedlings subjected to the artificial inoculation with Armillaria ostoyae (Romagn.) Herink. It was found that increased air CO2 concentration reduces the intensity of pine and spruce seedlings infection by A. ostoyae, what was expressed both by the greater number of healthy and lower number of died seedlings at the end of 16−months−long experiment. However, the statistical significance of the observed differences was confirmed in case of only one out of three A. ostoyae isolates used in the experiment. It was also found that during the first 12 months of the experiment growth of pine and spruce seedlings was significantly stimulated by 1000 ppm air CO2 concentration compared to the ambient air conditions (approximately 380 ppm CO2) with not statistically significant effect of A. ostoyae presence. It was manifested for both tree species with significantly higher values of diameter at the stem base in all variants subjected to increased air CO2 concentration. No such difference was observed for the height of seedlings. All the findings suggest that elevated air CO2 concentration may compensate negative impact of disease on growth at the early stages of pathogen attack

    The influence of stand canopy openness on the growth of common yew (Taxus baccata L.)

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    The aim of this study was to evaluate the development of common yew, Taxus baccata L., with respect to canopy openness. The plants were growing in ex-situ conservation plantations (established in 2008) in the understory of different tree species. Eleven forest plantations belonging to the following five forest districts were inventoried: Rokita, Baligród, Kołaczyce, Międzylesie and Henryków. In each plantation, the height and height increment of 200 yews were measured and gap light transmission indices were determined. The canopy species affecting yew growth most significantly were oak (Quercus sp.) and Scots pine (Pinus sylvestris L.), followed by Norway spruce (Picea abies Karst.), silver fir (Abies alba L.) and European beech (Fagus sylvatica L.). The most favorable development of yew occurred at 30% canopy openness. An increasing light transmission index correlated with a decrease in the proportion of treelike yews. An insufficient amount of light resulted in a low height increment of yews growing under the canopy and an extended period of direct competition of yews with herbaceous species
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