Laser Treatment of Pancreatic Cancer with Immunostimulating Interstitial Laser Thermotherapy Protocol: Safety and Feasibility Results From Two Phase 2a Studies.

PURPOSE: Ablative techniques have emerged as new potential therapeutic options for patients with locally advanced pancreatic cancer (LAPC). We explored the safety and feasibility of using TRANBERG|Thermal Therapy System (Clinical Laserthermia Systems AB, Lund, Sweden) in feedback mode for immunostimulating Interstitial Laser Thermotherapy (imILT) protocol, the newest ablative technique introduced for the treatment of LAPC. METHODS: The safety and feasibility results after the use of imILT protocol treatment in 15 patients of a prospective series of postsystemic therapy LAPC in two high-volume European institutions, the General and Pancreatic Unit of the Pancreas Institute, of the University of Verona, Italy, and the Department of Surgical Oncology of the Institut Paoli-Calmettes of Marseille, France, were assessed. RESULTS: The mean age was 66 ± 5 years, with a mean tumor size of 34.6 (±8) mm. The median number of cycles of pre-imILT chemotherapy was 6 (6-12). The procedure was performed in 13 of 15 (86.6%) cases; indeed, in two cases, the procedure was not performed; in one, the procedure was considered technically demanding; in the other, liver metastases were found intraoperatively. In all treated cases, the procedure was completed. Three late pancreatic fistulas developed over four overall adverse events (26.6%) and were attributed to imILT. Mortality was nil. A learning curve is necessary to interpret and manage the laser parameters. CONCLUSIONS: Safety, feasibility, and device handling outcomes of using TRANBERG|Thermal Therapy System with temperature probes in feedback mode and imILT protocol on LAPC were not satisfactory. The metastatic setting may be appropriate to evaluate the hypothetic abscopal effect.#NCT02702986 and #NCT02973217.

Advances in borderline resectable pancreatic adenocarcinoma.

Pancreatic adenocarcinoma is one of the most lethal cancers in oncology. Pancreatic cancer is the third most common cause of cancer-related mortality in the United States. As the years have progressed, the importance of a multidisciplinary and multimodal approach to pancreatic cancer care has been recognized and is now recommended in all major society guidelines. A subset of pancreatic cancer, borderline resectable pancreatic cancer (BRPC), has emerged as a distinct clinical entity for which specialized treatment plans are now being developed. The medical oncologist, surgical oncologist, and radiation oncologist must work jointly to help deliver the best clinical outcome for the patient with pancreatic cancer. In this discussion, we describe the current state of surgical, locoregional therapies and systemic therapy in BRPC.

Comparison of antioxidative effects between radon and thoron inhalation in mouse organs.

Radon therapy has been traditionally performed globally for oxidative stress-related diseases. Many researchers have studied the beneficial effects of radon exposure in living organisms. However, the effects of thoron, a radioisotope of radon, have not been fully examined. In this study, we aimed to compare the biological effects of radon and thoron inhalation on mouse organs with a focus on oxidative stress. Male BALB/c mice were randomly divided into 15 groups: sham inhalation, radon inhalation at a dose of 500 Bq/m3 or 2000 Bq/m3, and thoron inhalation at a dose of 500 Bq/m3 or 2000 Bq/m3 were carried out. Immediately after inhalation, mouse tissues were excised for biochemical assays. The results showed a significant increase in superoxide dismutase and total glutathione, and a significant decrease in lipid peroxide following thoron inhalation under several conditions. Additionally, similar effects were observed for different doses and inhalation times between radon and thoron. Our results suggest that thoron inhalation also exerts antioxidative effects against oxidative stress in organs. However, the inhalation conditions should be carefully analyzed because of the differences in physical characteristics between radon and thoron.

Perfusion CT to Assess Response to Neoadjuvant Chemotherapy and Radiation Therapy in Pancreatic Ductal Adenocarcinoma: Initial Experience.

BackgroundChange in tumor size at CT is insufficient for reliable assessment of treatment response after neoadjuvant chemotherapy and radiation therapy (CRT) and shows poor correlation with histologic grading of response.PurposeTo investigate the use of perfusion CT to predict the response of pancreatic ductal adenocarcinoma (PDA) to CRT.Materials and MethodsBetween June 2016 and May 2018, study participants with biopsy-proven PDA were prospectively recruited to undergo perfusion CT before and after planned CRT. Blood flow (BF), blood volume (BV), and permeability-surface area product (PSP) were quantified from CT images. Participants were categorized into responders and nonresponders according to therapy response. The Mann-Whitney test was used to compare the baseline perfusion values between responders and nonresponders, and the Wilcoxon matched-pairs signed rank test was used to compare perfusion values before and after CRT.ResultsThe final cohort of 21 participants (median age, 68 years; interquartile range [IQR], 65-72 years; eight men) underwent dynamic perfusion (dual-source) CT before neoadjuvant CRT. All participants underwent pancreatectomy. Eighteen participants underwent post-CRT perfusion CT. Baseline BF was higher in responders (n = 10) than in nonresponders (n = 11) (median, 44 [IQR, 39-56] vs 28 [IQR, 16-52] mL/100 g/min; P = .04), while BV and PSP were similar between groups (median BV, 4.3 [IQR, 3.5-6.9] vs 2.0 [IQR, 1.6-6.5] mL/100 g, P = .15; median PSP, 25 [IQR, 21-30] vs 20 [IQR, 10-34] mL/100 g/min, P = .31). Response Evaluation Criteria in Solid Tumors (RECIST) and carbohydrate antigen (CA) 19-9 showed no correlation with perfusion parameters (eg, RECIST and BF: r = 0.05, P = .84, 95% confidence interval [CI]: -0.40, 0.48; CA 19-9 and BF: r = 0.06, P = .78, 95% CI: -0.39, 0.49) or histopathologic response (r = 0.16, P = .47, 95% CI: -0.3, 0.57 and r = 0.09, P = .71, 95% CI: -0.37, 0.51, respectively). For responders, perfusion parameters increased after CRT (eg, median BF, 54 [IQR, 42-73] vs 43 [IQR, 28-53] mL/100 g/min; P = .04). The perfusion change in nonresponders was not significant (median BF, 43 [IQR, 28-53] vs 33 [IQR, 16-52] mL/100 g/min; P = .06).ConclusionPerfusion CT may be useful in helping predict the histopathologic response to therapy in pancreatic ductal adenocarcinoma.© RSNA, 2019See also the editorial by Sinitsyn in this issue.

Irreversible electroporation versus radiotherapy after induction chemotherapy on survival in patients with locally advanced pancreatic cancer: a propensity score analysis.

BACKGROUND: Locally advanced pancreatic cancer (LAPC) represents more than one third of pancreatic cancers and owns poor survival after the standard chemotherapy. Irreversible electroporation (IRE) is a novel method and has been recently used in LAPC. The aim of this study was to compare the efficacy of IRE and radiotherapy after induction chemotherapy for patients with LAPC. METHODS: From August 2015 to August 2017, a total of 76 patients with biopsy proven LAPC and who had received IRE or radiotherapy after chemotherapy were included. Thirty-two pairs of patients were selected through propensity score matching (PSM) analysis and the efficacy of two treatments was compared. RESULTS: Before PSM analysis, after induction chemotherapy, patients with LAPC benefited more in terms of overall survival (OS) and progression free survival (PFS) from IRE, compared with radiotherapy (2-year OS rates, 53.5% vs 26.9%, p = 0.039; 2-year PFS rates, 28.4% vs 13.3%, p = 0.045). After PSM analysis, the survival benefits of OS and PFS of patients after induction chemotherapy followed by IRE were more obvious than those of patients treated with radiotherapy (2-year OS rates, 53.5% vs 20.7%, p = 0.011; 2-year PFS rates, 28.4% vs 5.6%, p = 0.004). Multivariate Cox regression analysis indicated that IRE after induction chemotherapy was identified as a significant favourable factor for both OS and PFS in both the whole and matched cohort. CONCLUSIONS: Induction chemotherapy followed by IRE is superior to induction chemotherapy followed by radiotherapy for treating LAPC. A randomized clinical trial comparing the efficacy of IRE and radiotherapy after the induction chemotherapy is therefore considerable.

Comparison of pancreatic respiratory motion management with three abdominal corsets for particle radiation therapy: Case study.

BACKGROUND AND PURPOSE: Abdominal organ motion seriously compromises the targeting accuracy for particle therapy in patients with pancreatic adenocarcinoma. This study compares three different abdominal corsets regarding their ability to reduce pancreatic motion and their potential usability in particle therapy. MATERIALS AND METHODS: A patient-individualized polyurethane (PU), a semi-individualized polyethylene (PE), and a patient-individualized three-dimensional-scan based polyethylene (3D-PE) corset were manufactured for one healthy volunteer. Time-resolved volumetric four-dimensional-magnetic resonance imaging (4D-MRI) and single-slice two-dimensional (2D) cine-MRI scans were acquired on two consecutive days to compare free-breathing motion patterns with and without corsets. The corset material properties, such as thickness variance, material homogeneity in Hounsfield units (HU) on computed tomography (CT) scans, and manufacturing features were compared. The water equivalent ratio (WER) of corset material samples was measured using a multi-layer ionization chamber for proton energies of 150 and 200 MeV. RESULTS: All corsets reduced the pancreatic motion on average by 9.6 mm in inferior-superior and by 3.2 mm in anterior-posterior direction. With corset, the breathing frequency was approximately doubled and the day-to-day motion variations were reduced. The WER measurements showed an average value of 0.993 and 0.956 for the PE and 3DPE corset, respectively, and of 0.298 for the PU corset. The PE and 3DPE corsets showed a constant thickness of 2.8 ± 0.2 and 3.8 ± 0.2 mm, respectively and a homogeneous material composition with a standard deviation (SD) of 31 and 32 HU, respectively. The PU corset showed a variable thickness of 4.2 - 25.6 mm and a heterogeneous structure with air inclusions with an SD of 113 HU. CONCLUSION: Abdominal corsets may be effective devices to reduce pancreatic motion. For particle therapy, PE-based corsets are preferred over PU-based corset due to their material homogeneity and constant thickness.

Radiation Therapy Induces Macrophages to Suppress T-Cell Responses Against Pancreatic Tumors in Mice.

BACKGROUND & AIMS: The role of radiation therapy in the treatment of patients with pancreatic ductal adenocarcinoma (PDA) is controversial. Randomized controlled trials investigating the efficacy of radiation therapy in patients with locally advanced unresectable PDA have reported mixed results, with effects ranging from modest benefit to worse outcomes compared with control therapies. We investigated whether radiation causes inflammatory cells to acquire an immune-suppressive phenotype that limits the therapeutic effects of radiation on invasive PDAs and accelerates progression of preinvasive foci. METHODS: We investigated the effects of radiation therapy in p48(Cre);LSL-Kras(G12D) (KC) and p48(Cre);LSLKras(G12D);LSL-Trp53(R172H) (KPC) mice, as well as in C57BL/6 mice with orthotopic tumors grown from FC1242 cells derived from KPC mice. Some mice were given neutralizing antibodies against macrophage colony-stimulating factor 1 (CSF1 or MCSF) or F4/80. Pancreata were exposed to doses of radiation ranging from 2 to 12 Gy and analyzed by flow cytometry. RESULTS: Pancreata of KC mice exposed to radiation had a higher frequency of advanced pancreatic intraepithelial lesions and more foci of invasive cancer than pancreata of unexposed mice (controls); radiation reduced survival time by more than 6 months. A greater proportion of macrophages from radiation treated invasive and preinvasive pancreatic tumors had an immune-suppressive, M2-like phenotype compared with control mice. Pancreata from mice exposed to radiation had fewer CD8(+) T cells than controls, and greater numbers of CD4(+) T cells of T-helper 2 and T-regulatory cell phenotypes. Adoptive transfer of T cells from irradiated PDA to tumors of control mice accelerated tumor growth. Radiation induced production of MCSF by PDA cells. A neutralizing antibody against MCSF prevented radiation from altering the phenotype of macrophages in tumors, increasing the anti-tumor T-cell response and slowing tumor growth. CONCLUSIONS: Radiation treatment causes macrophages murine PDA to acquire an immune-suppressive phenotype and disabled T-cell-mediated anti-tumor responses. MCSF blockade negates this effect, allowing radiation to have increased efficacy in slowing tumor growth.

Radionuclide Therapy for Neuroendocrine Tumors.

Peptide receptor radionuclide therapy (PRRT) is a form of systemic radiotherapy that allows targeted delivery of radionuclides to tumor cells expressing high levels of somatostatin receptors. The two radiopeptides most commonly used for PRRT, 90Y-DOTATOC and 177Lu-DOTATATE, have been successfully employed for more than a decade for the treatment of advanced neuroendocrine tumors (NETs). Recently, the phase III, randomized NETTER-1 trial has compared 177Lu-DOTATATE versus high-dose octreotide LAR in patients with progressive, metastatic midgut NETs, demonstrating exceptional tolerability and efficacy. This review summarizes recent developments in the field of radionuclide therapy for gastroenteropancreatic and lung NETs and considers possible strategies to further enhance its clinical efficacy.

Increased pancreatic cancer risk following radiotherapy for testicular cancer.

BACKGROUND: Pancreatic cancer risk is elevated among testicular cancer (TC) survivors. However, the roles of specific treatments are unclear. METHODS: Among 23 982 5-year TC survivors diagnosed during 1947-1991, doses from radiotherapy to the pancreas were estimated for 80 pancreatic cancer patients and 145 matched controls. Chemotherapy details were recorded. Logistic regression was used to estimate odds ratios (ORs). RESULTS: Cumulative incidence of second primary pancreatic cancer was 1.1% at 30 years after TC diagnosis. Radiotherapy (72 (90%) cases and 115 (80%) controls) was associated with a 2.9-fold (95% confidence interval (CI) 1.0-7.8) increased risk. The OR increased linearly by 0.12 per Gy to the pancreas (P-trend<0.001), with an OR of 4.6 (95% CI 1.9-11.0) for ⩾25 Gy vs <25 Gy. Radiation-related risks remained elevated ⩾20 years after TC diagnosis (P=0.020). The risk increased with the number of cycles of chemotherapy with alkylating or platinum agents (P=0.057), although only one case was exposed to platinum. CONCLUSIONS: A dose-response relationship exists between radiation to the pancreas and subsequent cancer risk, and persists for over 20 years. These excesses, although small, should be considered when radiotherapy with exposure to the pancreas is considered for newly diagnosed patients. Additional data are needed on the role of chemotherapy.

Environmental risk factors for pancreatic cancer: an update.

Pancreatic cancer (PC) is one of the most aggressive diseases. Only 10 % of all PC cases are thought to be due to genetic factors. Here, we analyzed the most recently published case-control association studies, meta-analyses, and cohort studies with the aim to summarize the main environmental factors that could have a role in PC. Among the most dangerous agents involved in the initiation phase, there are the inhalation of cigarette smoke, and the exposure to mutagenic nitrosamines, organ-chlorinated compounds, heavy metals, and ionizing radiations. Moreover, pancreatitis, high doses of alcohol drinking, the body microbial infections, obesity, diabetes, gallstones and/or cholecystectomy, and the accumulation of asbestos fibers seem to play a crucial role in the progression of the disease. However, some of these agents act both as initiators and promoters in pancreatic acinar cells. Protective agents include dietary flavonoids, marine omega-3, vitamin D, fruit, vegetables, and the habit of regular physical activity. The identification of the factors involved in PC initiation and progression could be of help in establishing novel therapeutic approaches by targeting the molecular signaling pathways responsive to these stimuli. Moreover, the identification of these factors could facilitate the development of strategies for an early diagnosis or measures of risk reduction for high-risk people.

Features of contrast enhancement in different methods of multislice computed tomography.

The purpose of this study was a comparison of the X-ray density in certain organs and anatomical structures and the determination of the radiation exposure during venous-arterial MSCT scanning and classical two-phase CT of organs of the abdominal cavity. It has been established that the technique of venous-arterial MSCT scanning provided a significant reduction of radiation dose during CT of organs of the abdominal cavity and could be used as an alternative to two-phase examination in the process of dynamic monitoring of cancer patients.

MicroRNA 23b regulates autophagy associated with radioresistance of pancreatic cancer cells.

BACKGROUND & AIMS: Tumor resistance to radiation is a challenge in the treatment of patients with pancreatic cancer. Improving our understanding of the mechanisms of radioresistance could lead to strategies to increase patients' response to therapy. We investigated the roles of microRNAs (miRNAs) involved in radioresistance of pancreatic cancer cells. METHODS: We established radioresistant pancreatic cancer cell lines and used array analysis to compare levels of different miRNAs between radioresistant cell lines and the parental cell lines from which they were derived. We transfected pancreatic cancer cells with miRNA mimics or inhibitors and evaluated their effects on cell radiosensitivity using a clonogenic survival assay. The effects of miRNA on autophagy were determined by transmission electron microscopy and immunoblot analysis. We used a luciferase reporter assay to identify messenger RNA targets of specific miRNAs. RESULTS: Radioresistant pancreatic cancer cells had reduced levels of the miRNA miR-23b and increased autophagy compared with cells that were not radioresistant. Overexpression of miR-23b inhibited radiation-induced autophagy, whereas an inhibitor of miR-23b promoted autophagy in pancreatic cancer cells. Overexpression of miR-23b sensitized pancreatic cancer cells to radiation. The target of miR-23b, ATG12, was overexpressed in radioresistant cells; levels of ATG12 protein correlated with the occurrence of autophagy. Expression of miR-23b blocked radiation-induced autophagy and sensitized pancreatic cancer cells to radiation. We observed an inverse correlation between the level of miR-23b and autophagy in human pancreatic cancer tissue samples. CONCLUSIONS: In pancreatic cancer cells, reduced levels of the miRNA miR-23b increase levels of ATG12 and autophagy to promote radioresistance. miR-23b might be used to increase the sensitivity of pancreatic cancer cells to radiation therapy.

Fibulin-3 negatively regulates ALDH1 via c-MET suppression and increases γ-radiation-induced sensitivity in some pancreatic cancer cell lines.

Fibulin-3 (FBLN-3) has been postulated to be either a tumor suppressor or promoter depending on the cell type, and hypermethylation of the FBLN-3 promoter is often associated with human disease, especially cancer. We report that the promoter region of the FBLN-3 was significantly methylated (>95%) in some pancreatic cancer cell lines and thus FBLN-3 was poorly expressed in pancreatic cancer cell lines such as AsPC-1 and MiaPaCa-2. FBLN-3 overexpression significantly down-regulated the cellular level of c-MET and inhibited hepatocyte growth factor-induced c-MET activation, which were closely associated with γ-radiation resistance of cancer cells. Moreover, we also showed that c-MET suppression or inactivation decreased the cellular level of ALDH1 isozymes (ALDH1A1 or ALDH1A3), which serve as cancer stem cell markers, and subsequently induced inhibition of cell growth in pancreatic cancer cells. Therefore, forced overexpression of FBLN-3 sensitized cells to cytotoxic agents such as γ-radiation and strongly inhibited the stemness and epithelial to mesenchymal transition (EMT) property of pancreatic cancer cells. On the other hand, if FBLN3 was suppressed in FBLN-3-expressing BxPC3 cells, the results were opposite. This study provides the first demonstration that the FBLN-3/c-MET/ALDH1 axis in pancreatic cancer cells partially modulates stemness and EMT as well as sensitization of cells to the detrimental effects of γ-radiation.

Dosimetric study for breathing-induced motion effects in an abdominal pancreas phantom for carbon ion mini-beam radiotherapy.

BACKGROUND: Particle mini-beam therapy exhibits promise in sparing healthy tissue through spatial fractionation, particularly notable for heavy ions, further enhancing the already favorable differential biological effectiveness at both target and entrance regions. However, breathing-induced organ motion affects particle mini-beam irradiation schemes since the organ displacements exceed the mini-beam structure dimensions, decreasing the advantages of spatial fractionation. PURPOSE: In this study, the impact of breathing-induced organ motion on the dose distribution was examined at the target and organs at risk(OARs) during carbon ion mini-beam irradiation for pancreatic cancer. METHODS: As a first step, the carbon ion mini-beam pattern was characterized with Monte Carlo simulations. To analyze the impact of breathing-induced organ motion on the dose distribution of a virtual pancreas tumor as target and related OARs, the anthropomorphic Pancreas Phantom for Ion beam Therapy (PPIeT) was irradiated with carbon ions. A mini-beam collimator was used to deliver a spatially fractionated dose distribution. During irradiation, varying breathing motion amplitudes were induced, ranging from 5 to 15 mm. Post-irradiation, the 2D dose pattern was analyzed, focusing on the full width at half maximum (FWHM), center-to-center distance (ctc), and the peak-to-valley dose ratio (PVDR). RESULTS: The mini-beam pattern was visible within OARs, while in the virtual pancreas tumor a more homogeneous dose distribution was achieved. Applied motion affected the mini-beam pattern within the kidney, one of the OARs, reducing the PVDR from 3.78  ± $\pm$  0.12 to 1.478  ± $\pm$  0.070 for the 15 mm motion amplitude. In the immobile OARs including the spine and the skin at the back, the PVDR did not change within 3.4% comparing reference and motion conditions. CONCLUSIONS: This study provides an initial understanding of how breathing-induced organ motion affects spatial fractionation during carbon ion irradiation, using an anthropomorphic phantom. A decrease in the PVDR was observed in the right kidney when breathing-induced motion was applied, potentially increasing the risk of damage to OARs. Therefore, further studies are needed to explore the clinical viability of mini-beam radiotherapy with carbon ions when irradiating abdominal regions.

Feasibility, safety and preliminary efficacy of preoperative stereotactic radiotherapy on the future pancreatic neck transection margin to reduce the risk of pancreatic fistula after high-risk pancreatoduodenectomy (FIBROPANC): protocol for a multicentre, single-arm trial.

INTRODUCTION: Postoperative pancreatic fistula (POPF) occurs in 25% of patients undergoing a high-risk pancreatoduodenectomy (PD) and is a driving cause of major morbidity, mortality, prolonged hospital stay and increased costs after PD. There is a need for perioperative methods to decrease these risks. In recent studies, preoperative chemoradiotherapy in patients with pancreatic ductal adenocarcinoma (PDAC) reduced the rate of POPF seemingly due to radiation-induced pancreatic fibrosis. However, patients with a high risk of POPF mostly have a non-pancreatic periampullary tumour and do not receive radiotherapy. Prospective studies using radiotherapy specifically to reduce the risk of POPF have not been performed. We aim to assess the safety, feasibility and preliminary efficacy of preoperative stereotactic radiotherapy on the future pancreatic neck transection margin to reduce the rate of POPF. METHODS AND ANALYSIS: In this multicentre, single-arm, phase II trial, we aim to assess the feasibility and safety of a single fraction of preoperative stereotactic radiotherapy (12 Gy) to a 4 cm area around the future pancreatic neck transection margin in patients at high risk of developing POPF after PD aimed to reduce the risk of grade B/C POPF. Adult patients scheduled for PD for malignant and premalignant periampullary tumours, excluding PDAC, with a pancreatic duct diameter ≤3 mm will be included in centres participating in the Dutch Pancreatic Cancer Group. The primary outcome is the safety and feasibility of single-dose preoperative stereotactic radiotherapy before PD. The most relevant secondary outcomes are grade B/C POPF and the difference in the extent of fibrosis between the radiated and non-radiated (uncinate margin) pancreas. Evaluation of endpoints will be performed after inclusion of 33 eligible patients. ETHICS AND DISSEMINATION: Ethical approval was obtained by the Amsterdam UMC's accredited Medical Research Ethics Committee (METC). All included patients are required to have provided written informed consent. The results of this trial will be used to determine the need for a randomised controlled phase III trial and submitted to a high-impact peer-reviewed medical journal regardless of the study outcome. TRIAL REGISTRATION NUMBER: NL72913 (Central Committee on Research involving Human Subjects Registry) and NCT05641233 (ClinicalTrials).

Can contrast media increase organ doses in CT examinations? A clinical study.

OBJECTIVE: The purpose of this article is to quantify the CT radiation dose increment in five organs resulting from the administration of iodinated contrast medium. MATERIALS AND METHODS: Forty consecutive patients who underwent both un-enhanced and contrast-enhanced thoracoabdominal CT were included in our retrospective study. The dose increase between CT before and after contrast agent administration was evaluated in the portal phase for the thyroid, liver, spleen, pancreas, and kidneys by applying a previously validated method. RESULTS: An increase in radiation dose was noted in all organs studied. Average dose increments were 19% for liver, 71% for kidneys, 33% for spleen and pancreas, and 41% for thyroid. Kidneys exhibited the maximum dose increment, whereas the pancreas showed the widest variance because of the differences in fibro-fatty involution. Finally, thyroids with high attenuation values on unenhanced CT showed a lower Hounsfield unit increase and, thus, a smaller increment in the dose. CONCLUSION: Our study showed an increase in radiation dose in several parenchymatous tissues on contrast-enhanced CT. Our method allowed us to evaluate the dose increase from the change in attenuation measured in Hounsfield units. Because diagnostic protocols require multiple acquisitions after the contrast agent administration, such a dose increase should be considered when optimizing these protocols.

[Morphological verification problems of Chernobyl factor influence on the prostate of coalminers of Donbas--liquidators of Chernobyl accident].

Problem of a diagnostic of Chernobyl factor influences on different organs and systems of Chernobyl accident liquidators are remain actually until now. Though morbidly background which development at unfavorable work conditions in underground coalminers prevents from objective identification features of Chernobyl factor influences. The qualitative and quantitative histological and immunohistochemical law of morphogenesis changes in prostate of Donbas's coalminer-non-liquidators Chernobyl accident in comparison with the group of Donbas's coalminers-liquidators Chernobyl accident which we were stationed non determined problem. This reason stipulates to development and practical use of mathematical model of morphogenesis of a prostatic gland changes.

Radiation dose to the pancreas and risk of diabetes mellitus in childhood cancer survivors: a retrospective cohort study.

BACKGROUND: Children and young adults treated with total body or abdominal radiotherapy have an increased risk of insulin resistance and diabetes mellitus. However, little is known of the effect of pancreas irradiation on the risk of diabetes. We assessed the relation between radiation exposure and occurrence of diabetes in a large cohort of long-term childhood cancer survivors. METHODS: We sent a questionnaire to 3468 survivors of a childhood cancer treated in eight centres in France and the UK between 1946 and 1985, of which 2520 were returned. Each self-declaration of diabetes was confirmed by contacting the patients' medical doctors. We estimated the radiation dose received by the tail, head, and body of the pancreas and 185 other anatomical sites during each course of radiotherapy from 1990 to 1995 for each child after reconstruction of the conditions in which irradiation was delivered. We investigated the relation between radiation dose to the pancreas and the risk of a subsequent diabetes diagnosis. FINDINGS: 65 cases of diabetes were validated. The risk of diabetes increased strongly with radiation dose to the tail of the pancreas, where the islets of Langerhans are concentrated, up to 20-29 Gy and then reached a plateau for higher radiation doses. The estimated relative risk at 1 Gy was 1·61 (95% CI 1·21-2·68). The radiation dose to the other parts of the pancreas did not have a significant effect. Compared with patients who did not receive radiotherapy, the relative risk of diabetes was 11·5 (95% CI 3·9-34·0) in patients who received 10 Gy or more to the tail of the pancreas. Results were unchanged after adjustment for body-mass index, despite its strong independent effect (p<0·0001), and were similar between men and women. Children younger than 2 years at time of radiotherapy were more sensitive to radiation than were older patients (relative risk at 1 Gy 2·1 [95% CI 1·4-4·3] vs 1·4 [95% CI 1·1-2·2] in older patients; p=0·02 for the difference). For the 511 patients who had received more than 10 Gy to the tail of the pancreas, the cumulative incidence of diabetes was 16% (95% CI 11-24). INTERPRETATION: Our study provides evidence of a dose-response relation between radiation exposure of pancreas and subsequent risk of diabetes. Because of the risks observed and the frequency of diabetes in general population, this finding raises important public health issues. The pancreas needs to be regarded as a critical organ when planning radiation therapy, particularly in children. Follow-up of patients who received abdominal irradiation should include diabetes screening.

Percutaneous ultrasonography and computed tomography guided pancreatic cryoablation: feasibility and safety assessment.

OBJECTIVE: To assess the safety and feasibility of percutaneous cryoablation on pancreatic cancer via ultrasonography (US) and computed tomography (CT) guidance. MATERIALS AND METHODS: This retrospective review was approved by the institutional review board and of informed consent. Thirty-two patients (18 men and 14 women; median age 62; age range, 30-77 years) with pancreatic cancer (stage II/III/IV, 3/11/18) treated with percutaneous US and CT guided cryoablations between February 2009 and February 2010 were eligible for this review. Thirteen tumors in pancreatic head and 19 in pancreatic body and/or tail measuring 2-11 cm (mean, 5.2 cm±8 [standard deviation]) were ablated with 49 procedures in total. Feasibility was analyzed by enhanced CT 1-3 months post procedure and safety was assessed by clinical signs, symptoms and laboratory results. RESULTS: Neither procedural death nor serious complications occurred. Fifteen tumors (46.9%) smaller than 5 cm were successfully ablated by one session of cryoablation. Twenty-seven patients experienced a ≥50% reduction in pain score, 22 experienced a 50% decrease in analgesic consumption and 16 experienced a ≥20 increase in Karnofsky Performance Status (KPS) Score. Partial response (PR) and stable disease (SD) turned up in 9 and 21 patients, respectively, lesions in whom were identified controlled by none enhancement on enhanced CT. Mean and median survival was 15.9 and 12.6 months, respectively. The 6-, 12- and 24-month survival rates were 82.8%, 54.7% and 27.3%, respectively. CONCLUSION: US and CT guided percutaneous cryoablation is a safe and promising local treatment for pancreatic cancer.