_____________________________________________________________________________________________________using coplanar beams with 6 MV photons and the treatment was performed with DHX LINAC, VARIAN System.Pretreatment kV CBCT images were obtained at 1, 2 and 3 day of irradiations set-up corrections were made before treatment if the translational setup error was greater than 3 mm in any direction.Subsequently a weekly kV CBCT was repeated for whole duration of treatment.Results: A total of 360 CBCT scans were acquired and analyzed.The systemic errors results 1.26 mm (SD ± 0.177) in RL direction, 1.25 mm (SD ± 0.187) in SI direction and 1.8 mm (SD ± 0.255 in AP direction.The range of deviations were 0-9 in RL directions, 0-5 mm in SI direction and 0-10 mm in AP direction.The frequencies of setup errors > 3 mm in RL direction was 3.9 %, in SI 8 % and AP directions 15.5 %, respectively.Analyzing the CBCT before set-up corrections the frequencies of set-up error > 3 mm were 17.8 %, 10.6 % and 5.6 % in AP, SI and RL respectively.After set-up errors corrections (corrections via couch shifts or patient repositioning) these rates were reduced to 13,3%, 7.2 and 2.2 % in PA, SI and RL direction, respectively. Conclusion:The results of our study confirmed that image guidance with kV CBCT represents an effective tool for measuring set-up accuracy in the treatment of H&N cancer patients.This study suggested that kV CBCT once a week is adequate to overcome the problem of set-up errors in head and neck cancer treated with IMRT technique.

Purpose or Objective: The Calypso 4D Localization System consists in an electromagnetic detection of implanted Beacon transponders in order to continuously track their moves.The use of this system requires a specific couch top and the introduction in the treatment beam of an electromagnetic array.The purpose of this study is to quantify the dosimetric impact of the new material introduction in photon beams.

The goal of this work was to evaluate the feasibility and outcome of intensity-modulated arc therapy ± cisplatin (IMAT ± C) followed by hysterectomy for locally advanced cervical cancer.

ESTRO 31 S541 also found that system doesn't provide sufficiently correct information for both rotation and translation when the angle is higher than 3°.Though this issue needs to be investigate further.In the second experiment we found a good correlation between EPID and AlignRT.Mean difference in the lat, long and vert direction was 0.052 ± 0.064 cm, 0.030 ± 0.084 cm, -0.130 ± 0.064 cm, respectively.Agreement of AlignRT with the couch position was in lat -0.027 ± 0.043 cm, long 0.003 ± 0.040 cm and vert 0.005 ± 0.050 cm.Conclusions: The AlighRT system is accurate and well correlated with our EPID verification method thus we will use it in the clinic for patient positioning.We have found that accuracy of our treatment table on one linac, is more an issue here, not the AlignRT software itself.Regarding the AlignRT setup information we have created a special protocol.We will use a 3 DOF (translations only) and maximum accepted rotation 3°.Any higher detected rotation have to be corrected independently.

Endobronchial metallic clips to guide

The association between chromosomal radiosensitivity and genetic predisposition to head and neck cancer was investigated in this study. In all, 101 head and neck cancer patients and 75 healthy control individuals were included in the study. The G 2 assay was used to measure chromosomal radiosensitivity. The results demonstrated that head and neck cancer patients had a statistically higher number of radiation-induced chromatid breaks than controls, with mean values of 1.23 and 1.10 breaks per cell, respectively ( P <0.001). Using the 90th percentile of the G 2 scores of the healthy individuals as a cutoff value for chromosomal radiosensitivity, 26% of the cancer patients were radiosensitive compared with 9% of the healthy controls ( P =0.008). The mean number of radiation-induced chromatid breaks and the proportion of radiosensitive individuals were highest for oral cavity cancer patients (1.26 breaks per cell, 38%) and pharynx cancer patients (1.27 breaks per cell, 35%). The difference between patients and controls was most pronounced in the lower age group (⩽50 years, 1.32 breaks per cell, 38%) and in the non- and light smoking patient group (⩽10 pack-years, 1.28 breaks per cell, 46%). In conclusion, enhanced chromosomal radiosensitivity is a marker of genetic predisposition to head and neck cancer, and the genetic contribution is highest for oral cavity and pharynx cancer patients and for early onset and non- and light smoking patients.

The aim of present study was to investigate the relation between physical dose related parameters and single nucleotide polymorphisms (SNPs) in DNA DSB repair genes XRCC3 (c.-1843 A>G, c.562-14 A>G, c.722 C>T), Rad51 (c.-3429 G>C, c.-3392 G>T), Lig4 (c.26 C>T, c.1704 T>C), Ku70 (c.-1310 C>G) and Ku80 (c.2110-2804 G>A) and development of acute normal tissue RT reactions. The study population consisted of 89 head and neck cancer patients treated with IMRT. All RT reactions were scored using the CTCAE scale for mucositis, dermatitis and dysphagia. The population was subdivided in a group with low and moderate radiosensitivity (CTC0-2) and a group with high radiosensitivity (CTC3) for each acute normal tissue effect. The polymorphic regions were analysed by PCR- RFLP or single base extension analysis (PCR- Snapshot). Analyses showed that if we compare the CTC0-2 and the CTC3 group, the mean dose to the oral cavity is significantly associated with the development of mucositis (p= 0.042). For dysphagia a statistically significant relation was found with the dose of the upper, mid and lower constrictor pharyngeus (CP) muscles. These physical factors are considered as confounding factors in the radiogenomics analyses of this study. The SNPs in the coding region of the XRCC3 gene (c.722 C>T) and in the 5’ UTR region of the Ku70 gene (c.-1310 C>G) were significantly associated with the risk of developing severe dysphagia (CTC3) and can therefore be considered as risk alleles. Heterozygous carriers of the variant allele had a respectively 4.47 (p= 0.033) and 4.17 (p=0.014) increased risk to develop acute swallowing problems. We developed a risk analysis model using logistic regression analysis to predict patients probability to suffer from severe dysphagia as a result of the RT treatment. In this model the CP dose and the information regarding XRCC3 c.722 C>T and Ku70 c.-1310 C>G genotypes were included. Using a cut off value of two times the median, the model provided us a sensitivity of 78.6% and a specificity of 77.6% for prediction of severe dysphagia. No association between the investigated polymorphisms and the development of mucositis or dermatitis was found. Considering the dose to the CP muscles as confounding factor in a logistic regression model, presence of the variant allele of XRCC3 c.722 and Ku70 c.-1310 is significantly associated with development of dysphagia. Using the paramount physical and biological parameters, we developed a risk model for prediction of patients risk for severe dysphagia.

1) Purpose/Objective: To report on toxicity, tumour response and resectability after IMAT ± cisplatin for primary irresectable carcinoma of the cervix. 2) Material/Methods: Sixteen patients with Figo IIB-IVA cervixcarcinoma (see table) were treated with a pre-operative approach consisting of IMAT ± cisplatin 40 mg/m² weekly. Pre-treatment work-up included clinical examination and imaging (18FDG-PET/CT and MRI). In 25 fractions, IMAT resulted in a simultaneously integrated boost to the primary tumour and the positive lymph nodes of respectively 62 Gy and 60 Gy (Dmed). A Dmed of 58 Gy and 56 Gy is prescribed to the CTV (uterus, cervix, upper vaginal 1/3 to 1/2 and parametria) and PTV. A minimal dose (D98) of 45 Gy was prescribed to the PTV of the elective lymph nodes (CTV_Lnn). Toxicity was scored weekly during IMAT and at 1, 3, 6, 9 and 12 months thereafter and from then 6-monthly. Within 4 weeks after IMAT, clinical and radiological (18FDG-PET/CT and MRI) examination was used to evaluate tumour resectability and to exclude metastatic disease. If resectable, Wertheim-Meigs (W-M) was performed within 6-8 weeks after end of IMAT. If tumour response was insufficient, brachytherapy (BT) was proposed. Tumour control was evaluated clinically (3-monthly) and with imaging (6-monthly) after W-M. 3) Results: No treatment interruptions or acute grade 3 acute toxicity occurred. Fourteen patients had sufficient response to make the tumour resectable. Two patients were medical inoperable, 2 refused surgery and 10 patients received W-M (63%). Details considering all patients are listed in the table. Pathologic data after W-M were: complete response, microscopic and macroscopic rest in 3, 5 and 2 patients respectively. All patients had tumour-free surgical margins and pN0 disease. BT was omitted from the treatment regimen in 9/10 cases of the operated group. Six and 12 months post-W-M pelvic control was achieved in all patients (9 and 5 respectively). Two patients had a distant relapse (8 and 9 months), 1died. In the non-operated group, 3 patients refused BT. Pelvic relapse occurred in 2 patients, time of relapse was 2 and 5 months. Three of the non-operated patients have distant failure, two died of disease. In all patients (FU >3 months), no late grade 3 toxicity occurred, one patient had late grade 2 diarrhoea. Conclusion: IMAT ± cisplatin has low toxicity and is excellent in rendering irresectable cervical cancer resectable with low toxicity. All operated patients had tumour free resection margins. No pelvic relapses have yet been observed in this patient group. Table 1. Patient characteristics in the whole study group, the hysterectomy group and the non-operated group. * 1 patient lost in follow-up 1 month after end of treatment

Intraoperative high-dose-rate brachytherapy (IBT) has been successfully used in locally advanced unresectable intraabdominal malignancy. We retrospectively evaluated the safety, feasibility, and general outcome of IBT following cytoreductive surgery.After radical resection, the target area to be treated by IBT was determined jointly by the surgeon and the radiation oncologist. A silicon template was used to position parallel hollow catheters spaced 1 cm apart against the area of interest. IBT doses were prescribed at 1 cm depth from the template surface and calculated using standard plans. Radiation was administered in a dedicated shielded room.Between August 2001 and February 2006, 10 patients (colorectal cancer n = 6, cervix cancer n = 1, extramedullar plasmocytoma n = 1, liposarcoma n = 1 and sacrococcygeal teratocarcinoma n = 1) were treated. The mean delivered IBT dose was 8 Gy (range 7.5-20). No postoperative mortality was seen, while major complications developed in one (10%) patient with a rectovaginal fistula and intraabdominal abscess. Five of the six colorectal cancer patients developed local recurrence while 3 also developed distant metastases. The mean disease-free and overall survival in this group was 8.5 months (range 4-15) and 25.5 months (range 10-48) respectively. Palliation of symptoms was observed in 89 % of cases.IBT combined with debulking surgery is feasible and can be safely performed. While cure is rarely achieved, IBT offers the potential to prolong local control and survival in locally unresectable intraabdominal cancer. Therefore, IBT can be considered as a valuable adjuvant in the therapeutic and palliative armamentarium in these selected patients.

This study investigates the association of microsatellite polymorphisms in XRCC1, XRCC3 and XRCC5 with the development of late radiation-induced radiotherapy reactions and examines the correlation between these microsatellites and cancer incidence. Sixty-two women with cervical or endometrial cancer treated with radiotherapy were included in the study. According to the CTCAEv3.0 scale, 22 patients showed late adverse radiotherapy reactions (grade 2 or more). PCR on lymphocyte DNA followed by automated fragment analysis was performed to examine the number of tandem repeat units at each locus. No significant association was found between the repeat length at any of the microsatellites in XRCC1, XRCC3 or XRCC5 and the incidence of late radiotherapy complications. Since higher odds ratios (ORs) were found for the rare XRCC1 [AC]11 and [AC]21 repeats (OR = 2.65, P = 0.325 and OR = 8.67, P = 0.093, respectively), the possible involvement of these small and large repeats in clinical radiosensitivity cannot be completely ruled out. When specific numbers of repeats were examined, no significant correlation was found between the microsatellite repeat length in XRCC1 and XRCC5 and cancer incidence. A weak correlation between XRCC3 [AC]16 homozygotes and cancer incidence was found (OR = 2.56, P = 0.055). A large-scale multicenter study of cancer patients with a high number of radiosensitive individuals is needed to clarify the value of rare polymorphic microsatellite repeats in XRCC1 and XRCC3 as a biomarker of clinical radiosensitivity or increased cancer risk.

Purpose: To examine the association of polymorphisms in XRCCI (194Arg/Trp, 280Arg/His, 399Arg/Gln, 632Gln/Gln), XRCC3 (5' UTR 4.541A > G, IVS5-14 17.893A > G, 241Thr/Met), and OGG1 (326Ser/Cys) with the development of late radiotherapy (RT) reactions and to assess the correlation between in vitro chromosomal radiosensitivity and clinical radiosensitivity.Methods and Materials: Sixty-two women with cervical or endometrial cancer treated with RT were included in the study. According to the Common Terminology Criteria for Adverse Events, version 3.0, scale, 22 patients showed late adverse RT reactions. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assays were performed to examine polymorphic sites, the G2 assay was used to measure chromosomal radiosensitivity, and patient groups were compared using actuarial methods.Results: The XRCC3 IVS5-14 polymorphic allele was significantly associated with the risk of developing late RT reactions (odds ratio 3.98, p = 0.025), and the XRCCI codon 194 variant showed a significant protective effect (p = 0.028). Patients with three or more risk alleles in XRCCI and XRCC3 had a significantly increased risk of developing normal tissue reactions (odds ratio 10.10,p = 0.001). The mean number of chromatid breaks per cell was significantly greater in patients with normal tissue reactions than in patients with no reactions (1.16 and 1.34, respectively; p = 0.002). Patients with high chromosomal radiosensitivity showed a 9.2-fold greater annual risk of complications than patients with intermediate chromosomal radiosensitivity. Combining the G2 analysis with the risk allele model allowed us to identify 23% of the patients with late normal tissue reactions, without false-positive results.Conclusion: The results of the present study showed that clinical radiosensitivity is associated with an enhanced G2 chromosomal radiosensitivity and is significantly associated with a combination of different polymorphisms in DNA repair genes. (c) 2005 Elsevier Inc.