Stereotactic radiotherapy (SBRT) as a sole or salvage therapy in non-small cell lung cancer patients.

The aim of this study is to present evaluation of treatment toxicity and the rate of local control in non-small cell lung cancer patients (NSCLC) treated with stereotactic body radiotherapy (SBRT). The analysis was performed on heterogenous group of 61 NSCLC patients, treated with SBRT between 2005 and 2008. It included 26 patients in clinical stage I, 5 in stage II, 22 in III and 8 in stage IV. In 30 patients SBRT was the only treatment, in 20 patients SBRT was a salvage therapy and in 11 patients SBRT was used as a boost after conventionally fractionated radiotherapy (CRT). The mean age was 67 yrs. Fifteen patients received chemotherapy in the course of treatment. Radiation doses were converted into Linear Quadratic Equivalent Dose at 2Gy per fraction (LQED2). The survival curves were plotted using Kaplan-Maier estimator and analyzed using log-rank test and Cox method. The LQED2 doses administered in stereotactic technique ranged from 8 Gy to 150 Gy and the fraction doses from 5 Gy to 24 Gy. The rate of 2 years local control correlated with LQED2: it was 81% in a group of patients who received over 110 Gy, compared to 51% and 33% in a group of patients who received 60-110 Gy and less than 30 Gy respectively. Prior radiotherapy and advanced clinical stage correlated with lower doses at SBRT and hence lower rate of local control. The tolerance of SBRT was satisfactory: there was no RTOG grade 3 - 4 toxicity. The results are consistent with findings of other authors and indicate that LQED2 doses delivered by SBRT in the treatment of NSCLC should be higher than 110 Gy whenever clinically feasible. SBRT used as a salvage therapy was less effective, because use of high doses was precluded due to consideration of normal tissue tolerance.

Transcriptional activity of telomerase complex in CD34- stem cells of cord blood in dependence of preparation time.

The aim of the study was to determine whether the expression of telomerase subunits encoding genes changes during the process of cord blood preparation. It should establish if the commonly accepted 24 hours time interval in stem cells kriopreservation procedure significantly influences their immortalization and so decreases the "quality" of cord blood stem cells. Investigation includes 69 women. Spontaneous labour was the inclusion condition. The material was collected at birth after clamping of umbilical cord by direct vasopuncture. CD34- cells were extracted from cord blood (MACS, Miltenyi Biotec; Bisley, Surrey, UK). The expression profile of telomerase activators and inhibitors encoding genes was determined using HG_U133A oligonucleotide microarray (Affymetrix). We used a real-time quantitative RT-PCR assay to quantify the telomerase TERT, hTR and TP1 subunits mRNA copy numbers in CD34- cells in 0, 6, 12 and 24 hours after cord blood collection. We observed significant decrease of numbers of copies of TERTA+B mRNA within the successive hours of observation. Significant decrease of numbers of TERTA mRNA copies was confirmed after 24 hours. However, we observed significant increase of numbers of copies of TERTB mRNA after 6 hours of observation. Similar level was maintained during another 6h. The significantly lower number of copies of TERTB mRNA was observed after 24h. We also observed significant increase of number of copies of TERT mRNA after 6 hours. Number of copies of TERT mRNA significantly decreased after another 6h, remaining, however, on a higher then initial one. The significant lower number of copies of TERT mRNA was observed 24h after delivery. The possible explanation of those results is discussed in the paper.