Transcriptional Inflammatory Signature in Healthy Donors and Different Radiotherapy Cancer Patients.

Cancer and ionizing radiation exposure are associated with inflammation. To identify a set of radiation-specific signatures of inflammation-associated genes in the blood of partially exposed radiotherapy patients, differential expression of 249 inflammatory genes was analyzed in blood samples from cancer patients and healthy individuals. The gene expression analysis on a cohort of 63 cancer patients (endometrial, head and neck, and prostate cancer) before and during radiotherapy (24 h, 48 h, ~1 week, ~4-8 weeks, and 1 month after the last fraction) identified 31 genes and 15 up- and 16 down-regulated genes. Transcription variability under normal conditions was determined using blood drawn on three separate occasions from four healthy donors. No difference in inflammatory expression between healthy donors and cancer patients could be detected prior to radiotherapy. Remarkably, repeated sampling of healthy donors revealed an individual endogenous inflammatory signature. Next, the potential confounding effect of concomitant inflammation was studied in the blood of seven healthy donors taken before and 24 h after a flu vaccine or ex vivo LPS (lipopolysaccharide) treatment; flu vaccination was not detected at the transcriptional level and LPS did not have any effect on the radiation-induced signature identified. Finally, we identified a radiation-specific signature of 31 genes in the blood of radiotherapy patients that were common for all cancers, regardless of the immune status of patients. Confirmation via MQRT-PCR was obtained for BCL6, MYD88, MYC, IL7, CCR4 and CCR7. This study offers the foundation for future research on biomarkers of radiation exposure, radiation sensitivity, and radiation toxicity for personalized radiotherapy treatment.

Metastases-directed stereotactic body radiotherapy in combination with targeted therapy or immunotherapy: systematic review and consensus recommendations by the EORTC-ESTRO OligoCare consortium.

Stereotactic body radiotherapy (SBRT) for patients with metastatic cancer, especially when characterised by a low tumour burden (ie, oligometastatic disease), receiving targeted therapy or immunotherapy has become a frequently practised and guideline-supported treatment strategy. Despite the increasing use in routine clinical practice, there is little information on the safety of combining SBRT with modern targeted therapy or immunotherapy and a paucity of high-level evidence to guide clinical management. A systematic literature review was performed to identify the toxicity profiles of combined metastases-directed SBRT and targeted therapy or immunotherapy. These results served as the basis for an international Delphi consensus process among 28 interdisciplinary experts who are members of the European Society for Radiotherapy and Oncology (ESTRO) and European Organisation for Research and Treatment of Cancer (EORTC) OligoCare consortium. Consensus was sought about risk mitigation strategies of metastases-directed SBRT combined with targeted therapy or immunotherapy; a potential need for and length of interruption to targeted therapy or immunotherapy around SBRT delivery; and potential adaptations of radiation dose and fractionation. Results of this systematic review and consensus process compile the best available evidence for safe combination of metastases-directed SBRT and targeted therapy or immunotherapy for patients with metastatic or oligometastatic cancer and aim to guide today's clinical practice and the design of future clinical trials.

Total body irradiation for standard treatment rooms: a robust sweeping beam technique with respect to the body shape.

Background: The purpose of this work is to improve a sweeping beam technique for total body irradiation (TBI) on a low flat couch using a varying patient thickness model. We designed a flat couch for total body irradiation in supine and prone position. Three generic arcs with rectangular segments for a patient torso thickness of 16, 22 and 28 cm were generated with respect to varying patient thickness of four particular parts of the body: head, torso, thighs and calves. Materials and methods: Longitudinal and transversal dose profiles were measured using an ionization chamber and the EBT3 gafchromic film in a solid water slab phantom. The robustness of the method was examined in phantoms of different thicknesses. Results: Measured dose homogeneity stays within ±10% of prescribed dose for all of the three patient thickness models. The robustness of the method was evaluated as the increase in dose in the phantom center of 0.7% per 1 cm reduction in phantom thickness. Conclusion: The method is applicable for the broad range of patient sizes, comfortable for patients, robust and suitable for standard treatment rooms with a standard linear accelerator. It requires minimal investments into equipment.

Cardiac doses of accelerated partial breast irradiation with perioperative multicatheter interstitial brachytherapy.

PURPOSE: To quantify mean heart dose (MHD) and doses to the left anterior descending artery (LAD) and left ventricle (LV) in a retrospective series of patients who underwent perioperative accelerated partial breast irradiation with multicatheter interstitial brachytherapy (MIB-APBI). METHODS: Sixty-eight patients with low-risk left breast cancer were treated with MIB-APBI at our institution between 2012 and 2017. Interstitial tubes were inserted during the tumorectomy and sentinel node biopsy and APBI was started 6 days later. The prescribed dose was 34 Gy in 10 fractions (twice a day) to the clinical target volume (CTV). The heart, LAD, and LV were contoured and the distance between each structure and the CTV was measured. The MHD, mean and maximum LAD doses (LAD mean/max), and mean LV doses (LV mean) were calculated and corrected to biologically equivalent doses in 2­Gy fractionation (EQD2). We also evaluated the impact of the distance between the cardiac structures and the CTV and of the volume receiving the prescribed dose (V100) and high-dose volume (V150) on heart dosimetry. RESULTS: Mean EQD2 for MHD, LAD mean/max, and mean LV were 0.9 ± 0.4 Gy (range 0.3-2.2), 1.6 ± 1.1 Gy (range, 0.4-5.6), 2.6 ± 1.9 Gy (range, 0.7-9.2), and 1.3 ± 0.6 Gy (range, 0.5-3.4), respectively. MHD, LAD mean/max, and LV mean significantly correlated with the distance between the CTV and these structures, but all doses were below the recommended limits (German Society of Radiation Oncology; DEGRO). The MHD and LV mean were significantly dependent on V100. CONCLUSION: Perioperative MIB-APBI resulted in low cardiac doses in our study. This finding provides further support for the value of this technique in well-selected patients with early-stage left breast cancer.

Treatment options for locally recurrent vulvar cancer.

OBJECTIVE: Summarizing of treatment options for locally recurrent vulvar cancer in patients after previous complex oncological treatment and presenting a case report from our department. METHODS: Presenting a case report of a patient after previous complex oncological treatment for spinocellular cancer of the vulva who presented with a locally recurrent tumor. The patient was treated with a wide radical local excision of the tumor followed by a posterior thigh flap graft. CONCLUSION: Surgical intervention is the primary mode of treatment in locally recurrent cancers of the vulva. Wide radical local excision as a mode of treatment can be optimized by the use of grafts aiding in wound healing.

In Vivo Validation of Alternative FDXR Transcripts in Human Blood in Response to Ionizing Radiation.

Following cell stress such as ionising radiation (IR) exposure, multiple cellular pathways are activated. We recently demonstrated that ferredoxin reductase (FDXR) has a remarkable IR-induced transcriptional responsiveness in blood. Here, we provided a first comprehensive FDXR variant profile following DNA damage. First, specific quantitative real-time polymerase chain reaction (qPCR) primers were designed to establish dose-responses for eight curated FDXR variants, all up-regulated after IR in a dose-dependent manner. The potential role of gender on the expression of these variants was tested, and neither the variants response to IR nor the background level of expression was profoundly affected; moreover, in vitro induction of inflammation temporarily counteracted IR response early after exposure. Importantly, transcriptional up-regulation of these variants was further confirmed in vivo in blood of radiotherapy patients. Full-length nanopore sequencing was performed to identify other FDXR variants and revealed the high responsiveness of FDXR-201 and FDXR-208. Moreover, FDXR-218 and FDXR-219 showed no detectable endogenous expression, but a clear detection after IR. Overall, we characterised 14 FDXR transcript variants and identified for the first time their response to DNA damage in vivo. Future studies are required to unravel the function of these splicing variants, but they already represent a new class of radiation exposure biomarkers.

Cardiotoxicity of radiation therapy in esophageal cancer.

With a development of radiotherapeutic techniques, availability of radiotherapy data on cardiotoxicity, and slowly improving esophageal cancer outcomes, an increasing emphasis is placed on the heart protection in radiation treated esophageal cancer patients. Radiation induced heart complications encompass mainly pericardial disease, cardiomyopathy, coronary artery atherosclerosis, valvular heart disease, and arrhythmias. The most frequent toxicity is pericardial effusion which is usually asymptomatic in the majority of patients. The use of modern radiotherapy techniques is expected to reduce the risk of cardiotoxicity, although this expectation has to be confirmed by clinical data.

Validation of dose distribution computation on sCT images generated from MRI scans by Philips MRCAT.

AIM: To evaluate calculation of treatment plans based on synthetic-CT (sCT) images generated from MRI. BACKGROUND: Because of better soft tissue contrast, MR images are used in addition to CT images for radiotherapy planning. However, registration of CT and MR images or repositioning between scanning sessions introduce systematic errors, hence suggestions for MRI-only therapy. The lack of information on electron density necessary for dose calculation leads to sCT (synthetic CT) generation. This work presents a comparison of dose distribution calculated on standard CT and sCT. MATERIALS AND METHODS: 10 prostate patients were included in this study. CT and MR images were collected for each patient and then water equivalent (WE) and MRCAT images were generated. The radiation plans were optimized on CT and then recalculated on MRCAT and WE data. 2D gamma analysis was also performed. RESULTS: The mean differences in the majority of investigated DVH points were in order of 1% up to 10%, including both MRCAT and WE dose distributions. Mean gamma pass for acceptance criteria 1%/1 mm were greater than 82.5%. Prescribed doses for target volumes and acceptable doses for organs at risk were met in almost all cases. CONCLUSIONS: The dose calculation accuracy on MRCAT was not significantly compromised in the majority of clinical relevant DVH points. The introduction of MRCAT into practise would eliminate systematic errors, increase patients' comfort and reduce treatment expenses. Institutions interested in MRCAT commissioning must, however, consider changes to established workflow.

The changes of tumour vascular endothelial growth factor expression after neoadjuvant chemoradiation in patients with rectal adenocarcinoma.

AIM OF THE STUDY: The aim was to examine the effects of neoadjuvant chemoradiotherapy on VEGF expression in patients with locally advanced rectal cancer. MATERIALS AND METHODS: A total of 53 patients with locally advanced rectal cancer were retrospectively studied. Neoadjuvant treatment comprised external beam radiation (50.4 Gy/28 fractions) with continuous infusion of 5-fluorouracil. Four to 6 weeks after the chemoradiotherapy, the patients underwent surgical resection. Immunohistochemistry was performed to assess VEGF expression in the pretreatment biopsies and in resected specimens. RESULTS: Resection with microscopic residual tumour (R1) was performed in two patients while in the remaining 51 patients radical resection with microscopically negative margins (R0) was possible. Downstaging after preoperative chemoradiotherapy was observed in 34 patients (64%). After chemoradiotherapy 24 patients (45%) had decreased VEGF expression, in 20 patients (38%) there was no change, and in two patients it was not possible to assess the dynamics of VEGF expression due to pathologic complete response after chemoradiotherapy. The five-year overall survival (OS) rate was 56% (95% CI: 43-70%). Although the median OS was 2.5 times shorter in patients who experienced decreased VEGF expression during therapy, this difference did not reach statistical significance. VEGF expression was not significant in Cox regression analysis or log-rank test. VEGF expression decreased after neoadjuvant chemoradiotherapy in most patients with rectal adenocarcinoma examined. This decrease was associated with a trend of inferior prognosis. CONCLUSIONS: VEGF expression decreased after neoadjuvant chemoradiotherapy in most patients examined. This decrease was associated with a trend of inferior prognosis.

Neoadjuvant chemoradiotherapy of rectal carcinoma : Baseline hematologic parameters influencing outcomes.

BACKGROUND: The link between the blood count and a systemic inflammatory response (SIR) is indisputable and well described. Pretreatment hematological parameters may predict the overall clinical outcomes in many types of cancer. Thus, this study aims to systematically evaluate the relationship between baseline blood count levels and treatment response in rectal cancer patients treated with neoadjuvant chemoradiotherapy. PATIENTS AND METHODS: From 2009-2015, 173 patients with locally advanced rectal cancer were retrospectively enrolled in the study and analyzed. The baseline blood count was recorded in all patients 1 week before chemoradiation. Tumor response was evaluated through pathologic findings. Blood count levels which included RBC (red blood cells), Hb (hemoglobin), PLT (platelet count), neutrophil count, WBC (white blood cells), NLR (neutrophil-to-lymphocyte ratio), and PLR (platelet-to-lymphocyte ratio) were analyzed in relation to tumor downstaging, pCR (pathologic complete response), OS (overall survival), and DFS (disease-free survival). RESULTS: Hb levels were associated with a response in logistic regression analysis: pCR (p = 0.05; OR 1.04, 95 % CI 1.00-1.07); T downstaging (p = 0.006; OR 1.03, 95 % CI 1.01-1.05); N downstaging (p = 0.09; OR 1.02, 95 % CI 1.00-1.04); T or N downstaging (p = 0.007; OR 1.04, 95 % CI 1.01-1.07); T and N downstaging (p = 0.02; OR 1.02, 95 % CI 1.00-1.04); Hb and RBC were the most significant parameters influencing OS; PLT was a negative prognostic factor for OS and DFS (p = 0.008 for OS); an NLR value of 2.8 was associated with the greatest significance for OS (p = 0.03) and primary tumor downstaging (p = 0.02). CONCLUSION: Knowledge of pretreatment hematological parameters appears to be an important prognostic factor in patients with rectal carcinoma.

Carrier molecules and extraction of circulating tumor DNA for next generation sequencing in colorectal cancer.

The aims of the study were: i) to compare circulating tumor DNA (ctDNA) yields obtained by different manual extraction procedures, ii) to evaluate the addition of various carrier molecules into the plasma to improve ctDNA extraction recovery, and iii) to use next generation sequencing (NGS) technology to analyze KRAS, BRAF, and NRAS somatic mutations in ctDNA from patients with metastatic colorectal cancer. Venous blood was obtained from patients who suffered from metastatic colorectal carcinoma. For plasma ctDNA extraction, the following carriers were tested: carrier RNA, polyadenylic acid, glycogen, linear acrylamide, yeast tRNA, salmon sperm DNA, and herring sperm DNA. Each extract was characterized by quantitative real-time PCR and next generation sequencing. The addition of polyadenylic acid had a significant positive effect on the amount of ctDNA eluted. The sequencing data revealed five cases of ctDNA mutated in KRAS and one patient with a BRAF mutation. An agreement of 86% was found between tumor tissues and ctDNA. Testing somatic mutations in ctDNA seems to be a promising tool to monitor dynamically changing genotypes of tumor cells circulating in the body. The optimized process of ctDNA extraction should help to obtain more reliable sequencing data in patients with metastatic colorectal cancer.

Hypersensitivity to chemoradiation in FANCA carrier with cervical carcinoma-A case report and review of the literature.

OBJECTIVE: Compared to Fanconi anemia (FA) patients with homozygous defective two-alleles inheritance, there is a scarce or no evidence on one defective allele FANCA carriers, with respect to their cancer incidence, clinical and in vitro radiosensitivity and chemosensitivity. On that account, we report a case of a 30-year old FANCA mutation carrier woman with uterine cervix adenocarcinoma who was treated with chemoradiotherapy, in which unexpected acute toxicity and fatal late morbidity occured. METHODS: We also report the results of an in vitro test for radiosensitivity, immunohistochemical examination with FANCA staining and human papillomavirus genotypization, and a review of the literature for FA carrier patients with respect to cancer incidence, clinical and in vitro response to chemo/radiotherapy, options of early heterozygosity detection, and methods of in vitro prediction of hypersensitivity to oncologic treatment. CONCLUSION: Although there are no standard guidelines for management of FA carriers with malignancies and reports about chemo- or radiosensitivity in this population are scarce; patients with FA-A heterozygosity may have a high rate of complications from chemo/radiotherapy. Up to now, an optimum method for the prediction of radiosensitivity and the best parameter has not been found. Clinical radioresponsiveness is unpredictable in FA carriers and there is a pressing need of new rapid and predictive in vitro assays of radiation responses. Until then, the treatment of FA carriers with malignancies should be individualized, with respect to potential hypersensitivity to ionizing radiation or cross-linking agents.

The Role of Adjuvant Radiotherapy in the Treatment of Breast Cancer.

The role of postmastectomy radiotherapy and regional nodal irradiation after radical mastectomy is defined in high-risk patients with locally advanced tumors, positive margins, and unfavorable biology. The benefit of postmastectomy radiotherapy in intermediate-risk patients (T3N0 tumors) remains a matter of controversy. It has been demonstrated that radiotherapy after breast-conserving surgery lowers the locoregional recurrence rate compared with surgery alone and improves the overall survival rate. In patients with four or more positive lymph nodes or extracapsular extension, regional lymph node irradiation is indicated regardless of the surgery type (breast-conserving surgery or mastectomy). Despite the consensus that patients with more than three positive lymph nodes should be treated with radiotherapy, there is controversy regarding the recommendations for patients with one to three involved lymph nodes. In patients with N0 disease with negative findings on axillary surgery, there is a trend to administer regional lymph node irradiation in patients with a high risk of recurrence. In patients treated with neoadjuvant systemic therapy and mastectomy, adjuvant radiotherapy should be administered in cases of clinical stage III and/or ≥ypN1. In patients treated with neoadjuvant systemic therapy and breast-conserving surgery, postoperative radiotherapy is indicated irrespective of pathological response.

High-dose-rate brachytherapy at 3 Gy per fraction for lip carcinoma: Treatment outcomes and toxicity at 5-years.

PURPOSE: Low-dose-rate brachytherapy (LDR-BT) is a well-established treatment for lip cancer. High-dose-rate (HDR)-BT is a promising alternative to LDR-BT, but data are limited. In this context, we retrospectively evaluated treatment outcomes in a series of patients who underwent HDR-BT for lip carcinoma between 2003 and 2021. MATERIALS AND METHODS: A total of 32 patients were included in this study, with a median age of 73.5 years (range, 61 - 88). The indications for HDR-BT were as follows: primary treatment (n = 17), adjuvant treatment (n = 3), and recurrent disease after surgery (n = 12). The prescribed dose was 18 fractions of 3 Gy administered twice daily. RESULTS: At a median followup of 45 months (range, 12 -232), the 5-year local recurrence-free interval was 96.9% (95% CI: 90.9-100%), the disease-free interval was 85% (95% CI: 70.9-99.1), and 5-year overall survival was 64.7% (95% CI: 44.7-84.8). Eleven patients died, all on age related comorbidities. Acute toxicity manifested as G1 dry desquamation in 6 patients (18.8%), G2 erythema in 10 patients (31.2%) and G3 confluent moist desquamation in 16 patients (50%). Late complications included G1 fibrosis (100% of cases). G1 and G2 depigmentation was observed in 8 (25%) and 6 (18%) patients, G1 telangiectasia occurred in 5 patients (16%). CONCLUSIONS: These data support the use of HDR-BT for lip cancer. The dose and fractionation schedule used in this study (18 fractions x 3 Gy twice daily) seems to be effective and safe.

Special Techniques of Adjuvant Breast Carcinoma Radiotherapy.

Modern radiotherapy techniques are designed to permit reduced irradiation of healthy tissue, resulting in a diminished risk of adverse effects and shortened recovery times. Several randomized studies have demonstrated the benefits of increased dosage to the tumor bed area in combination with whole breast irradiation (WBI). Conventional WBI treatment following breast-conserving procedures, which required 5-7 weeks of daily treatments, has been reduced to 3-4 weeks when using hyperfractionated regimens. The dosage administration improves local control, albeit with poorer cosmesis. The method of accelerated partial breast irradiation (APBI) shortens the treatment period whilst reducing the irradiated volume. APBI can be delivered using intraoperative radiation, brachytherapy, or external beam radiotherapy. Currently available data support the use of external beam partial breast irradiation in selected patients. Modern radiotherapy techniques make it possible to achieve favorable cosmesis in most patients undergoing immediate breast reconstruction surgery, and studies confirm that current methods of external beam radiation allow an acceptable coverage of target volumes both in the reconstructed breast and in the regional lymphatic nodes.

High-Dose-Rate Brachytherapy as an Organ-Sparing Treatment for Early Penile Cancer.

BACKGROUND: Low-dose-rate brachytherapy is an effective organ-sparing treatment for patients with early-stage penile cancer. However, only limited data are available on the role of high-dose-rate brachytherapy (HDR-BT) in this clinical setting. METHODS: Between 2002 and 2020, 31 patients with early penile cancer were treated at our center with interstitial HDR BT at a dose of 18 × 3 Gy twice daily. A breast brachytherapy template was used for the fixation of stainless hollow needles. RESULTS: The median follow-up was 117.5 months (range, 5-210). Eight patients (25.8%) developed a recurrence; of these, seven were salvaged by partial amputation. Six patients died of internal comorbidities or a second cancer. The probability of local control at 5 and 10 years was 80.7% (95% CI: 63.7-97.7%) and 68.3% (95% CI: 44.0-92.6%), respectively. Cause-specific survival was 100%. Only one case of radiation-induced necrosis was observed. The probability of penile sparing at 5 and 10 years was 80.6% (95% CI: 63.45-97.7%) and 62.1% (95% CI: 34.8-89.4%), respectively. CONCLUSIONS: These results show that HDR-BT for penile cancer can achieve results comparable to LDR-BT with organ sparing. Despite the relatively large patient cohort-the second largest reported to date in this clinical setting-prospective data from larger samples are needed to confirm the role of HDR-BT in penile cancer.

Positron Emission Tomography-Guided Bone Marrow-Sparing Radiation Therapy for Locoregionally Advanced Cervix Cancer: Final Results From the INTERTECC Phase II/III Trial.

PURPOSE: To test effects of positron emission tomography (PET)-based bone marrow-sparing (BMS) image-guided intensity modulated radiation therapy (IG-IMRT) on efficacy and toxicity for patients with locoregionally advanced cervical cancer. METHODS AND MATERIALS: In an international phase II/III trial, patients with stage IB-IVA cervical carcinoma were treated with either PET-based BMS-IG-IMRT (PET-BMS-IMRT group) or standard image-guided IMRT (IMRT group), with concurrent cisplatin (40 mg/m2 weekly), followed by brachytherapy. The phase II component nonrandomly assigned patients to PET-BMS-IMRT or standard IMRT. The phase III trial randomized patients to PET-BMS-IMRT versus IMRT, with a primary endpoint of progression-free survival (PFS) but was closed early for futility. Phase III patients were analyzed separately and in combination with phase II patients, comparing acute hematologic toxicity, cisplatin delivery, PFS, overall survival (OS), and patterns of failure. In a post-hoc exploratory analysis, we investigated the association between pretreatment absolute lymphocyte count (ALC) and OS. RESULTS: In total, 101 patients were enrolled on the phase II/III trial, including 29 enrolled in phase III (PET-BMS-IMRT group: 16; IMRT group: 13) before early closure. Median follow-up was 33 months for phase III patients and 39 months for all patients. PFS and OS at 5 years for all patients were 73.6% (95% confidence interval [CI], 64.9%-84.3%) and 84% (95% CI, 76%-92.9%]), respectively. There were no differences in number of cisplatin cycles, OS, PFS, or patterns of failure between groups for the combined cohort. The incidence of acute grade ≥ 3 neutropenia was significantly lower in the PET-BMS-IMRT group compared with IMRT for randomized patients (19% vs 54%, χ2P = .048) and in the combined cohort (13% vs 35%, χ2P = .01). Patients with pretreatment ALC ≤ 1.5 k/µL had nonsignificantly worse OS on multivariable analysis (HR 2.85; 95% CI, 0.94-8.62; adjusted P = .216), compared with patients with ALC > 1.5 k/µL. There was no difference in posttreatment ALC by treatment group. CONCLUSIONS: PET-BMS-IMRT significantly reduced acute grade ≥3 neutropenia, but not treatment-related lymphopenia, compared with standard IMRT. We found no evidence that PET-BMS-IMRT affected chemotherapy delivery or long-term outcomes, and weak evidence of an association between pretreatment ALC and OS.

Intensity-modulated radiotherapy in the treatment of subhepatic carcinomas.

BACKGROUND/AIMS: The aim of our study was to evaluate preliminary results of intensity modulated radiotherapy (IMRT) in patients with inoperable subhepatic tumors. METHODOLOGY: Thirteen patients with inoperable cholangiocarcinoma or gall bladder carcinoma were treated by biliary drainage and intensity modulated radiotherapy. In patients with tumors limited to the biliary duct only tumor stenosis was irradiated to the dose of 50-60 Gy. In patients with bulky extraductal tumors the dose was 50 Gy/25 fractions to the whole tumor and an integrated boost was used to raise the dose to the malignant stenosis to 60 Gy/25 fractions. RESULTS: Doses to organs at risk (duodenum, small intestine, liver) were in tolerable limits. In four patients transient fever occurred; one patient had duodenal bleeding that resolved after conservative treatment. Recurrent dilatation of the biliary tract was observed in 4 patients and was managed by exchange of the internal biliary drainage. Median survival was 10.4 months, 5 patients survived for more than one year following diagnosis. CONCLUSIONS: IMRT of inoperable extrahepatic biliary tract tumors allows application of high doses of radiation to the tumor with effective sparing of healthy tissues. The control of jaundice is good. In selected cases IMRT may prolong overall survival.

Daily prostate volume and position monitoring using implanted gold markers and on-board imaging during radiotherapy.

PURPOSE: This study aimed to evaluate prostate volume changes and prostate motions during radiotherapy. METHODS: In 2010, twenty-five patients were treated for prostate cancer by external beam radiotherapy with implanted fiducial markers. Coordinates of three gold markers on kilovoltage images were calculated daily. Volume changes in target structure were observed through changes in intermarker distances. Differences in patient position between laser-tattoo alignment and gold marker localization were evaluated. Intrafraction motion was assessed by measuring marker displacement on kilovoltage images acquired before and after fraction delivery. RESULTS: Prostate shrinkage was observed in 60% of patients. The average shrinkage was 7% of the prostate's initial volume. Corrections after laser-tattoo alignment remained mostly below 1 cm. The difference between marker centroid position on the actual images and the planning images was 2 +/- 1 mm on average. The extension of intrafraction movements was 7.6 +/- 0.2 mm on average. CONCLUSIONS: In our retrospective study, the possibility for prostate volume changes during radiotherapy was revealed. Intrafraction movements turned out to be the limiting factor in safety margin reduction.