FETAL DOSE ESTIMATION DURING PREGNANCY USING GATE MONTE CARLO SIMULATION: APPLICATION OF HODGKIN'S LYMPHOMA RADIOTHERAPY.

The aim of this study is to estimate the fetal radiation dose for a pregnant patient treated for Hodgkin's lymphoma. Due to the supradiaphragmatic extensions, two plans are used for this treatment, one for supra-clavicular and the other for cervical lymph nodes, with beam energies of 18 and 6 MV, respectively. We model the ELEKTA accelerator (Versa HD Ltd, Crawly, UK) and the pregnant patient using GATE code. The accelerator is modelled based on the vendor-supplied data and the pregnant patient is modeled with a voxelized pregnant woman phantom (Katja, 29 years old) at the 24th week of pregnancy. In each plan, we estimate the absorbed dose of each fetus organ by delivering a 2 Gy for one fraction and then multiplying the result by 15 fractions to get the total prescribed dose, then we calculate the mean fetal absorbed dose. The results indicate that the mean absorbed fetal dose was 26.18 mGy.

Individualised Estimation of Quality-adjusted Survival Benefit and Cost-effectiveness of Proton Beam Therapy in Intermediate-stage Hodgkin Lymphoma.

AIMS: Radiotherapy for Hodgkin lymphoma leads to the irradiation of organs at risk (OAR), which may confer excess risks of late effects. Comparative dosimetry studies show that proton beam therapy (PBT) may reduce OAR irradiation compared with photon radiotherapy, but PBT is more expensive and treatment capacity is limited. The purpose of this study is to inform the appropriateness of PBT for intermediate-stage Hodgkin lymphoma (ISHL). MATERIALS AND METHODS: A microsimulation model simulating the course of ISHL, background mortality and late effects was used to estimate comparative quality-adjusted life years (QALYs) lived and healthcare costs after consolidative pencil beam scanning PBT or volumetric modulated arc therapy (VMAT), both in deep-inspiration breath-hold. Outcomes were compared for 606 illustrative patients covering a spectrum of clinical presentations, varying by two age strata (20 and 40 years), both sexes, three smoking statuses (never, former and current) and 61 pairs of OAR radiation doses from a comparative planning study. Both undiscounted and discounted outcomes at 3.5% yearly discount were estimated. The maximum excess cost of PBT that might be considered cost-effective by the UK's National Institute for Health and Care Excellence was calculated. RESULTS: OAR doses, smoking status and discount rate had large impacts on QALYs gained with PBT. Current smokers benefited the most, averaging 0.605 undiscounted QALYs (range -0.341 to 2.171) and 0.146 discounted QALYs (range -0.067 to 0.686), whereas never smokers benefited the least, averaging 0.074 undiscounted QALYs (range -0.196 to 0.491) and 0.017 discounted QALYs (range -0.030 to 0.086). For the gain in discounted QALYs to be considered cost-effective, PBT would have to cost at most £4812 more than VMAT for current smokers and £645 more for never smokers. This is below preliminary National Health Service cost estimates of PBT over photon radiotherapy. CONCLUSION: In a UK setting, PBT for ISHL may not be considered cost-effective. However, the degree of unquantifiable uncertainty is substantial.

Response assessment by positron emission tomography-computed tomography as compared with contrast-enhanced computed tomography in childhood Hodgkin lymphoma can reduce the need for radiotherapy in low- and middle-income countries.

INTRODUCTION: The InPOG-HL-15-01, a multicentric prospective study, used a risk-stratified and response-based approach with doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) backbone to treat children and adolescents with newly diagnosed Hodgkin lymphoma (HL) and reduce the use of radiation therapy (RT). Children/adolescents with bulky disease or inadequate response at early response assessment (ERA) after two cycles of chemotherapy were assigned to receive RT. For ERA, positron emission tomography computed tomography (PET-CT) was recommended but not mandatory in view of limited access. This study aimed to compare the impact of using contrast-enhanced computed tomography (CECT) and PET-CT on treatment decisions and outcomes. METHODOLOGY: 396 patients were enrolled and 382 had an ERA at the assigned time point. Satisfactory response was defined as Deauville score 3 or less for patients undergoing PET-CT and complete response (CR)/very good partial response (VGPR) for patients undergoing CECT. Outcomes of interest incorporate 5 year event-free survival (EFS), EFS including abandonment (EFSa), and overall survival (OS). RESULTS: At ERA, satisfactory response was documented in 277 out of 382 (72.5%) participants and this was significantly higher in PET-CT (151 out of 186, 81.2%) as compared with CECT-based assessments (126 out of 196, 64.3%) respectively (p value < .001). Amongst the 203 patients with nonbulky disease (wherein the indication for RT was entirely dependent on ERA), 96 out of 114 (84.2%) and 61 out of 89 (68.5%) patients achieved a satisfactory response according to the PET-CT and CECT (p value = .008) respectively and hence a lesser proportion of patients in the PET-CT arm received RT. Despite a lower usage of RT the 5 year OS of both groups, ERA based on CECT (91.8%) versus PET-CT (94.1%) was comparable (p value = .391) and so was the 5 year EFS (86.7 vs. 85.5%, p value = .724). CONCLUSION: Use of PET-CT as the modality for ERA is more likely to indicate a satisfactory response as compared with CECT and thereby decreases the need for RT in response-based treatment algorithm for HL-afflicted children. The reduction in the application of RT did not impact the overall outcome and plausibly would lower the risk of delayed toxic effects.

Cost-Effectiveness of Colorectal Cancer Surveillance in Hodgkin Lymphoma Survivors Treated with Procarbazine and/or Infradiaphragmatic Radiotherapy.

BACKGROUND: Hodgkin lymphoma survivors treated with infradiaphragmatic radiotherapy (IRT) and/or procarbazine have an increased risk of developing colorectal cancer. We investigated the cost-effectiveness of colorectal cancer surveillance in Dutch Hodgkin lymphoma survivors to determine the optimal surveillance strategy for different Hodgkin lymphoma subgroups. METHODS: The Microsimulation Screening Analysis-Colon model was adjusted to reflect colorectal cancer and other-cause mortality risk in Hodgkin lymphoma survivors. Ninety colorectal cancer surveillance strategies were evaluated varying in starting and stopping age, interval, and modality [colonoscopy, fecal immunochemical test (FIT, OC-Sensor; cutoffs: 10/20/47 µg Hb/g feces), and multi-target stool DNA test (Cologuard)]. Analyses were also stratified per primary treatment (IRT and procarbazine or procarbazine without IRT). Colorectal cancer deaths averted (compared with no surveillance) and incremental cost-effectiveness ratios (ICER) were primary outcomes. The optimal surveillance strategy was identified assuming a willingness-to-pay threshold of €20,000 per life-years gained (LYG). RESULTS: Overall, the optimal surveillance strategy was annual FIT (47 µg) from age 45 to 70 years, which might avert 70% of colorectal cancer deaths in Hodgkin lymphoma survivors (compared with no surveillance; ICER:€18,000/LYG). The optimal surveillance strategy in Hodgkin lymphoma survivors treated with procarbazine without IRT was biennial FIT (47 µg) from age 45 to 70 years (colorectal cancer mortality averted 56%; ICER:€15,000/LYG), and when treated with IRT and procarbazine, annual FIT (47 µg) surveillance from age 40 to 70 was most cost-effective (colorectal cancer mortality averted 75%; ICER:€13,000/LYG). CONCLUSIONS: Colorectal cancer surveillance in Hodgkin lymphoma survivors is cost-effective and should commence earlier than screening occurs in population screening programs. For all subgroups, FIT surveillance was the most cost-effective strategy. IMPACT: Colorectal cancer surveillance should be implemented in Hodgkin lymphoma survivors.

Is Radiation Therapy Cost-Effective in the Positron Emission Tomography/Computed Tomography Era for Early-Stage Favorable Hodgkin Lymphoma With Alternative Payment Models?

PURPOSE: Despite multiple randomized trials, variation in practice remains regarding the most effective treatment for early-stage, favorable-risk Hodgkin lymphoma. With increasing emphasis on alternative payment models, we investigate the cost-effectiveness of chemotherapy alone versus combined modality therapy (CMT). METHODS AND MATERIALS: A Markov model was formed to compared 2 cycles of adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD) to 2 cycles of ABVD followed by 20 Gy in 10 fractions involved-site radiation therapy. Modalities were compared using the incremental cost-effectiveness ratio, with effectiveness measured in quality-adjusted life years (QALYs) and evaluated with a willingness to pay a threshold of $100,000 per QALY gained. RESULTS: The base case analysis showed that CMT is cost-effective compared with ABVD alone, with an incremental cost-effectiveness ratio of $8028 per QALY gained and an incremental cost of $236 gaining 0.029 QALYs. On sensitivity analyses, the results were the most sensitive to changes in recurrence rates. If the recurrence rate differences were ≥6%, CMT was cost-effective. CONCLUSIONS: CMT is a cost-effective strategy for early-stage, favorable-risk Hodgkin lymphoma based on currently available evidence. However, small variations in recurrence-rate estimates dramatically affect strategy cost-effectiveness.

Establishing Cost-Effective Allocation of Proton Therapy for Patients With Mediastinal Hodgkin Lymphoma.

PURPOSE: For curative treatment of Hodgkin lymphoma, radiation therapy benefit must be weighed against toxicity. Although more costly, proton radiation therapy reduces dose to healthy tissue, potentially improving the therapeutic ratio compared with photons. We sought to determine the cost-effectiveness of proton versus photon therapy for mediastinal Hodgkin lymphoma (MHL) based on reduced heart disease. METHODS AND MATERIALS: Our model approach was 2-fold: (1) Use patient-level dosimetric information for a cost-effectiveness analysis using a Markov cohort model. (2) Use population-based data to develop guidelines for policymakers to determine thresholds of proton therapy favorability for a given photon dose. The HD14 trial informed relapse risk; coronary heart disease risk was informed by the Framingham risk calculator modified by the mean heart dose (MHD) from radiation. Sensitivity analyses assessed model robustness and identified the most influential model assumptions. A 30-year-old adult with MHL was the base case using 30.6-Gy proton therapy versus photon intensity modulated radiation therapy. RESULTS: Proton therapy was not cost-effective in the base case for male ($129,000/ quality-adjusted life years [QALYs]) or female patients ($196,000/QALY). A 5-Gy MHD decrease was associated with proton therapy incremental cost-effectiveness ratio <$100,000/QALY in 40% of scenarios. The hazard ratio associating MHD and heart disease was the most influential clinical parameter. CONCLUSIONS: Proton therapy may be cost-effective a select minority of patients with MHL based on age, sex, and MHD reduction. We present guidance for clinicians using MHD to aid decision-making for radiation therapy modality.

Comparing second cancer risk for multiple radiotherapy modalities in survivors of hodgkin lymphoma.

OBJECTIVES: To assess if excess absolute risk (EAR) of radiation-induced solid cancer can be used to rank radiotherapy plans for treatment of Hodgkin lymphoma (HL) in a statistically significant way. METHODS: EAR models, calibrated with data from the Life Span Study and HL survivors, have been incorporated into a voxelised risk-calculation software, which is used to compare four treatment modalities planned for five virtual HL patients. Organ-specific parameters are generated repeatedly in a Monte Carlo fashion to model their uncertainties. This in turn enables a quantitative estimation of the EAR uncertainties. RESULTS: Parameter-driven uncertainties on total EAR are around 13%, decreasing to around 2-5% for relative EAR comparisons. Total EAR estimations indicate that intensity modulated proton therapy decreases the average risk by 40% compared to the intensity modulated radiation therapy plan, 28% compared to the volumetric modulated arc therapy plan whereas the three-dimensional conformal radiation therapy plan is equivalent within the uncertainty. CONCLUSION: Relative EAR is a useful metric for distinguishing between radiotherapy plans in terms of second cancer risk. ADVANCES IN KNOWLEDGE: Relative EAR is not dominated by model or parameter uncertainties and can be used to guide the choice of radiotherapy for HL patients.

Radiation-induced dystrophic calcification and severe valvular stenosis: the central role of multimodality 3D cardiac imaging in disease assessment and planning of combined transcatheter aortic and mitral valve replacement.

Cardiac disease after mediastinal radiotherapy can result in progressive valvular thickening and dystrophic calcification with ensuing leaflet restriction and dysfunction. This can ultimately manifest as valvular stenosis and/or regurgitation. We report a case of a 61-year-old woman with symptomatic severe aortic stenosis and severe mitral stenosis due to severe dystrophic calcification postmediastinal radiotherapy for lymphoma. She was deemed surgically inoperable due to dense, continuous calcification throughout the leaflets and annuli of both valves, aortomitral continuity, proximal coronary arteries and proximal porcelain aorta. She underwent simultaneous transcatheter aortic valve replacement and transcatheter mitral valve replacement with an excellent technical and clinical result at 7-month follow-up. We also describe the central role of multimodality three-dimensional transoesophageal echocardiography and multidetector cardiac CT imaging in assessing the severity of valve disease, characterising the nature of cardiac calcification and guiding decisions on surgical operability and transcatheter intervention.

Assessment of Radiation Doses Delivered to Organs at Risk Among Patients With Early-Stage Favorable Hodgkin Lymphoma Treated With Contemporary Radiation Therapy.

Importance: Response-adapted randomized trials have used positron emission tomography-computed tomography to attempt to identify patients with early-stage favorable Hodgkin lymphoma (ESFHL) who could be treated with doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) without radiation therapy (RT). While maximal efficacy is demonstrated with combined modality therapy, RT is often omitted in fear of late adverse effects; however, the application of modern RT could limit these toxic effects. Objective: To determine the radiation doses delivered to organs at risk with modern involved-site RT among patients with ESFHL treated with 20 Gy after 2 cycles of ABVD. Design, Setting, and Participants: This case series included 42 adult patients with ESFHL (according to the German Hodgkin Study Group criteria) who were treated between 2010 and 2019, achieved complete response by positron emission tomography-computed tomography (1-3 on 5-point scale) following 2 cycles of ABVD, and then received consolidative RT. The study was conducted at a single comprehensive cancer center. Exposures: 2 cycles of chemotherapy followed by 20-Gy involved-site RT. Main Outcomes and Measures: The medical records of patients with ESFHL were examined. Organs at risk were contoured, and doses were calculated. Progression-free survival, defined from date of diagnosis to disease progression, relapse, or death, and overall survival were estimated using the Kaplan-Meier method. Results: The cohort comprised 42 patients with ESFHL (median [range] age at diagnosis, 35 [18-74] years; 18 [43%] women; 24 [57%] with stage II disease). At a median follow-up of 44.6 (95% CI, 27.6-61.6) months, the 3-year progression-free survival and overall survival rates were 91.2% (95% CI, 74.9%-97.1%) and 97.0% (95% CI, 80.4%-99.6%), respectively. The mean heart dose was less than 5 Gy (mean, 0.8 Gy; SD, 1.5 Gy; range, 0-4.8 Gy) in all patients. The mean (SD) breast dose for both breasts was 0.1 (0.2) Gy (left breast range, 0-1.0 Gy; right breast range, 0-0.9 Gy). Conclusions and Relevance: In this study, combined modality therapy with 2 cycles of ABVD and 20 Gy for ESFHL was highly effective and avoided excess doses to organs at risk, which may limit long-term toxic effects.

Intensity modulated proton therapy compared to volumetric modulated arc therapy in the irradiation of young female patients with hodgkin's lymphoma. Assessment of risk of toxicity and secondary cancer induction.

BACKGROUND: To investigate the role of intensity modulated proton therapy (IMPT) compared to volumetric modulated arc therapy (VMAT) for advanced supradiaphragmatic Hodgkin's lymphoma (HL) in young female patients by assessing dosimetric features and modelling the risk of treatment related complications and radiation-induced secondary malignancies. METHODS: A group of 20 cases (planned according to the involved-site approach) were retrospectively investigated in a comparative planning study. Intensity modulated proton plans (IMPT) were compared to VMAT RapidArc plans (RA). Estimates of toxicity were derived from normal tissue complication probability (NTCP) calculations with either the Lyman or the Poisson models for a number of endpoints. Estimates of the risk of secondary cancer induction were determined for lungs, breasts, esophagus and thyroid. A simple model-based selection strategy was considered as a feasibility proof for the individualized selection of patients suitable for proton therapy. RESULTS: IMPT and VMAT plans resulted equivalent in terms of target dose distributions, both were capable to ensure high coverage and homogeneity. In terms of conformality, IMPT resulted ~ 10% better than RA plans. Concerning organs at risk, IMPT data presented a systematic improvement (highly significant) over RA for all organs, particularly in the dose range up to 20Gy. This lead to a composite average reduction of NTCP of 2.90 ± 2.24 and a reduction of 0.26 ± 0.22 in the relative risk of cardiac failures. The excess absolute risk per 10,000 patients-years of secondary cancer induction was reduced, with IMPT, of 9.1 ± 3.2, 7.2 ± 3.7 for breast and lung compared to RA. The gain in EAR for thyroid and esophagus was lower than 1. Depending on the arbitrary thresholds applied, the selection rate for proton treatment would have ranged from 5 to 75%. CONCLUSION: In relation to young female patients with advanced supradiaphragmatic HL, IMPT can in general offer improved dose-volume sparing of organs at risk leading to an anticipated lower risk of early or late treatment related toxicities. This would reflect also in significantly lower risk of secondary malignancies induction compared to advanced photon based techniques. Depending on the selection thresholds and with all the limits of a non-validated and very basic model, it can be anticipated that a significant fraction of patients might be suitable for proton treatments if all the risk factors would be accounted for.

Cost-Utility of Early Breast Cancer Surveillance in Survivors of Thoracic Radiation-Treated Adolescent Hodgkin Lymphoma.

BACKGROUND: Adolescent women treated for Hodgkin lymphoma (HL) are at increased risk of breast cancer (BC). We evaluate the cost-utility of eight high-risk BC surveillance strategies for this population, including the Children's Oncology Group guideline of same-day annual mammography and magnetic resonance imaging (MRI) beginning at age 25 years. METHODS: A discrete event simulation model was used to simulate the life histories of a cohort of 500 000 25-year-old women treated for HL at age 15 years. We estimated BC incidence and mortality, life expectancy, quality-adjusted life-years (QALYs), health-care costs, and the relative cost-utility (incremental cost-utility ratio [ICUR]) under the eight assessed surveillance strategies. One-way sensitivity analysis enabled modeling of uncertainty evaluation. A publicly funded health-care payer perspective was adopted. RESULTS: Costs across the eight screening strategies ranged from $32 643 to $43 739, whereas QALYs ranged from 24.419 to 24.480. In an incremental cost-effectiveness analysis, annual mammography beginning at age 25 years was associated with an ICUR of $43 000/QALY gained, annual MRI beginning at age 25 years with a switch to annual mammography at age 50 years had an ICUR of $148 000/QALY, and annual MRI beginning at age 25 years had an ICUR of $227 222/QALY. Among all assessed surveillance strategies, the differences in life expectancy were small. CONCLUSIONS: Current high-risk BC surveillance guidelines do not reflect the most cost-effective strategy in survivors of adolescent HL. The results suggest that groups at high risk of BC may require high-risk surveillance guidelines that reflect their specific risk profile.

A Ukrainian multicenter prospective study of the value of PET/ CT prognostic role in primary patients with Hodgkins lymphoma in a real-life cohort.

INTRODUCTION: In recent years, the positron emission tomography combined with computed tomography (PET/CT) has changed and the treatment approaches in Hodgkins lymphoma (HL) patients have entirely improved. The main idea in several studies is the use of PET/CT and the International Prognostic Score (IPS) protocols in identification of patients within a high-risk group and potential early relapse/refractory disease. MATERIALS AND METHODS: This study was based on PET/CT evaluation and treatment strategies of patients from eight Centers of Hematology in Ukraine. The patients included were newly dia-gnosed with HL and were aged 67 years or younger. They received a treatment with ABVD or BEACOPP-14/esc or “switched-regimens” (ABVD + BEACOPP-esc/14, BEACOPP-esc/14 + ABVD). The primary endpoints were to assess a correlation between PET/CT findings at the time of dia-gnosis, response to the therapy and clinical outcome (relapse/death) for patients with early and advanced stages of HL. The secondary endpoints were to evaluate the relationship between IPS and PET/CT findings. RESULTS: The study group included 106 patients. The overall response rate (ORR) was 90.5%. The ORR for patients with stages I-II was 96.5% (55/57) vs. 91% (41/45) for stage III-IV patients. In total, the disease progression occurred in 58.3% (7/12) of PET2+ patients and in 13.3% (12/90) of PET2 patients (P < 0.05). No significant difference was found between the event free survival (EFS) rate and IPS for patients with PET2+ vs. PET2, (log-rank test; P = 0.4). The PET3 status was found in 88.8% (79/89) of the study group patients and 1.2% (10/89) had a PET3+ status (P < 0.05). Using the Cox regression, we confirmed a significant correlation between EFS with PET3 Deauville scale (DS) and IPS. Patients with DS 1-2, DS 3 and DS 4-5 had a 1-year event-free survival of 94.4%, 100% and 33%, respectively (HR 0.56; 95% CI 1.07-2.8; P < 0.02). Our multivariable analysis showed no statistically significant correlation between PET2+ and PET3+ status and extranodal involvement or large tumor burden. CONCLUSION: The results of using PET/CT in patients with primary HL demonstrated a high prognostic value of PET at the end of the treatment. In addition, we confirmed the predictive role of IPS prognostic model in the treatment outcome depending on PET status.

Theranostic radiopharmaceuticals: established agents in current use.

Although use of the term "theranostic" is relatively recent, the concept goes back to the earliest days of nuclear medicine, with the use of radioiodine for diagnosis and therapy of benign and malignant thyroid disease being arguably the most successful molecular radiotherapy in history. A diagnostic scan with 123I-, 124I-, or a low activity of 131I-iodide is followed by therapy with high activity 131I-iodide. Similarly, adrenergic tumours such as phaeochromocytoma and neuroblastoma can be imaged with 123I-metaiodobenzylguanidine and treated with 131I-metaiodobenzylguanidine. Bone scintigraphy can be used to select patients with painful bone metastases from prostate cancer who may benefit from treatment with beta- or alpha-particle emitting bone seeking agents, the most recent and successful of which is 223Ra radium chloride. Anti-CD20 monoclonal antibodies can be used to image and treat non-Hodgkins lymphoma, though this has not been as commercially successful as initially predicted. More recently established theranostics include somatostatin receptor targeting peptides for diagnosis and treatment of neuroendocrine tumours with agents such as 68Ga-DOTATATE and 177Lu-DOTATATE, respectively. Finally, agents which target prostate-specific membrane antigen are becoming increasingly widely available, despite the current lack of a commercial product. With the recent licensing of the somatostatin peptides and the rapid adoption of 68Ga- and 177Lu-labelled prostate-specific membrane antigen targeting agents, we have built upon the experience of radioiodine and are already seeing a great expansion in the availability of widely accepted theranostic radiopharmaceuticals.

A hybrid phantom Monte Carlo-based method for historical reconstruction of organ doses in patients treated with cobalt-60 for Hodgkin's lymphoma.

Historical radiotherapy treatment plans lack 3D images sets required for estimating mean organ doses to patients. Alternatively, Monte Carlo-based models of radiotherapy devices coupled with whole-body computational phantoms can permit estimates of historical in-field and out-of-field organ doses as needed for studies associating radiation exposure and late tissue toxicities. In recreating historical patient treatments with 60Co based systems, the major components to be modeled include the source capsule, surrounding shielding layers, collimators (both fixed and adjustable), and trimmers as needed to vary field size. In this study, a computational model and experimental validation of the Theratron T-1000 are presented. Model validation is based upon in-field commissioning data collected at the University of Florida, published out-of-field data from the British Journal of Radiology (BJR) Supplement 25, and out-of-field measurements performed at the University of Wisconsin's Accredited Dosimetry Calibration Laboratory (UWADCL). The computational model of the Theratron T-1000 agrees with central axis percentage depth dose data to within 2% for 6 × 6 to 30 × 30 cm2 fields. Out-of-field doses were found to vary between 0.6% to 2.4% of central axis dose at 10 cm from field edge and 0.42% to 0.97% of central axis dose at 20 cm from the field edge, all at 5 cm depth. Absolute and relative differences between computed and measured out-of-field doses varied between ±2.5% and ±100%, respectively, at distances up to 60 cm from the central axis. The source-term model was subsequently combined with patient-morphometry matched computational hybrid phantoms as a method for estimating in-field and out-of-field organ doses for patients treated for Hodgkin's Lymphoma. By changing field size and position, and adding patient-specific field shaping blocks, more complex historical treatment set-ups can be to recreated, particularly those for which 2D or 3D image sets are unavailable.

Colorectal cancer surveillance in Hodgkin lymphoma survivors at increased risk of therapy-related colorectal cancer: study design.

BACKGROUND: Second primary malignancies are a major cause of excess morbidity and mortality in cancer survivors. Hodgkin lymphoma survivors who were treated with infradiaphragmatic radiotherapy and/or high-dose procarbazine have an increased risk to develop colorectal cancer. Colonoscopy surveillance plays an important role in colorectal cancer prevention by removal of the precursor lesions (adenomas) and early detection of cancer, resulting in improved survival rates. Therefore, Hodgkin lymphoma survivors treated with infradiaphragmatic radiotherapy and/or high-dose procarbazine could benefit from colonoscopy, or other surveillance modalities, which are expected to reduce colorectal cancer incidence and mortality. Current knowledge on clinicopathological and molecular characteristics of therapy-related colorectal cancer is limited. The pathogenesis of such colorectal cancers might be different from the pathogenesis in the general population and therefore these patients might require a different clinical approach. We designed a study with the primary aim to assess the diagnostic yield of a first surveillance colonoscopy among Hodgkin lymphoma survivors at increased risk of colorectal cancer and to compare these results with different screening modalities in the general population. Secondary aims include assessment of the test characteristics of stool tests and evaluation of burden, acceptance and satisfaction of CRC surveillance through two questionnaires. METHODS/DESIGN: This prospective multicenter cohort study will include Hodgkin lymphoma survivors who survived ≥8 years after treatment with infradiaphragmatic radiotherapy and/or procarbazine (planned inclusion of 259 participants). Study procedures will consist of a surveillance colonoscopy with removal of precursor lesions (adenomas) and 6-8 normal colonic tissue biopsies, a fecal immunochemical test and a stool DNA test. All neoplastic lesions encountered will be classified using relevant histomorphological, immunohistochemical and molecular analyses in order to obtain more insight into colorectal carcinogenesis in Hodgkin lymphoma survivors. The Miscan-model will be used for cost-effectiveness analyses. DISCUSSION: Evaluation of the diagnostic performance, patient acceptance and burden of colorectal cancer surveillance is necessary for future implementation of an individualized colorectal cancer surveillance program for Hodgkin lymphoma survivors. In addition, more insight into treatment-induced colorectal carcinogenesis will provide the first step towards prevention and personalized treatment. This information may be extrapolated to other groups of cancer survivors. TRIAL REGISTRATION: Registered at the Dutch Trial Registry (NTR): NTR4961 .

[Current situation and perspectives of proton therapy]. / État des lieux et perspectives de la protonthérapie.

Proton beam therapy is indicated as a treatment for some rare tumours and paediatric tumours because the technique allows a good local control with minimal toxicity; the growing number of centres that use proton beam therapy is associated with an increase of dosimetric and clinical data for other malignant tumours as well. This paper reviews potential indications of proton beam therapy. A systematic review on Medline was performed with the following keywords proton beam therapy, cancer, heavy particle, charged particle. No phase III trial has been published using proton beam therapy in comparison with the best photon therapy, but numerous retrospective and dosimetric studies have revealed an advantage of proton beam therapy compared to photons, above all in tumours next to parallel organs at risk (thoracic and abdominal tumours). This could be accompanied with a better safety profile and/or a better tumoural control; numerous phase 0, I, II, III and IV studies are ongoing to examine these hypotheses in more common cancers. Use of proton beam therapy is growing for common cancers within clinical trials but some indications could be applied sooner since in silico analysis showed major advantages with this technique.

Low-dose chest computed tomography for lung cancer screening among Hodgkin lymphoma survivors: a cost-effectiveness analysis.

PURPOSE: Hodgkin lymphoma (HL) survivors face an increased risk of treatment-related lung cancer. Screening with low-dose computed tomography (LDCT) may allow detection of early stage, resectable cancers. We developed a Markov decision-analytic and cost-effectiveness model to estimate the merits of annual LDCT screening among HL survivors. METHODS AND MATERIALS: Population databases and HL-specific literature informed key model parameters, including lung cancer rates and stage distribution, cause-specific survival estimates, and utilities. Relative risks accounted for radiation therapy (RT) technique, smoking status (>10 pack-years or current smokers vs not), age at HL diagnosis, time from HL treatment, and excess radiation from LDCTs. LDCT assumptions, including expected stage-shift, false-positive rates, and likely additional workup were derived from the National Lung Screening Trial and preliminary results from an internal phase 2 protocol that performed annual LDCTs in 53 HL survivors. We assumed a 3% discount rate and a willingness-to-pay (WTP) threshold of $50,000 per quality-adjusted life year (QALY). RESULTS: Annual LDCT screening was cost effective for all smokers. A male smoker treated with mantle RT at age 25 achieved maximum QALYs by initiating screening 12 years post-HL, with a life expectancy benefit of 2.1 months and an incremental cost of $34,841/QALY. Among nonsmokers, annual screening produced a QALY benefit in some cases, but the incremental cost was not below the WTP threshold for any patient subsets. As age at HL diagnosis increased, earlier initiation of screening improved outcomes. Sensitivity analyses revealed that the model was most sensitive to the lung cancer incidence and mortality rates and expected stage-shift from screening. CONCLUSIONS: HL survivors are an important high-risk population that may benefit from screening, especially those treated in the past with large radiation fields including mantle or involved-field RT. Screening may be cost effective for all smokers but possibly not for nonsmokers despite a small life expectancy benefit.

Is there an indication for digital subtraction angiography in the assessment of irradiation-induced vascular damage before free flap surgery by the means of the internal mammary vessels?

Secondary breast reconstruction is increasingly performed after postmastectomy radiotherapy. Damage to blood vessel walls is one of the adverse effects of irradiation therapy, which may jeopardize reconstructive free flap surgery. It would be of great importance to be informed about the quality of the recipient vessel before reconstructive surgery. The aim of this study was to prospectively assess the value of preoperative angiography in the assessment of radiation-induced arterial damage and to relate the findings to the degree of vascular damage found during the operation and with histology. This study included women who had been treated with thoracic radiotherapy and required free flap breast reconstruction. Preoperative angiographic, intraoperative quality and histological findings of vessels were scored and compared together with the occurrence of postoperative complications. In 34 patients a total of 40 free flaps breast reconstruction were performed. Total 21 internal mammary arteries had been within the field of irradiation. In only two out of six patients with aberrant angiographies the internal mammary artery has been within the field of irradiation. This study concludes that damage to the internal mammary vessels cannot always be detected preoperatively by angiography, or even by intraoperative examination.

Assessment of volume segmentation in radiotherapy of adolescents; a treatment planning study by the Swedish Workgroup for Paediatric Radiotherapy.

BACKGROUND AND PURPOSE: The variability in target delineation for similar cases between centres treating paediatric and adolescent patients, and the apparent differences in interpretation of radiotherapy guidelines in the treatment protocols encouraged us to perform a dummy-run study as a part of our quality assurance work. The aim was to identify and quantify differences in the segmentation of target volumes and organs at risk (OARs) and to analyse the treatment plans and dose distributions. MATERIALS AND METHODS: Four patient cases were selected: Wilm's tumour, Hodgkin's disease, rhabdomyosarcoma of the prostate and chordoma of the skull base. The five participating centres received the same patient-related material. They introduced the cases in their treatment planning system, delineated target volumes and OARs and created treatment plans. Dose-volume histograms were retrieved for relevant structures and volumes and dose metrics were derived and compared, e.g. target volumes and their concordance, dose homogeneity index (HI), treated and irradiated volumes, remaining volume at risk and relevant Vx and Dx values. RESULTS: We found significant differences in target segmentation in the majority of the cases. The planning target volumes (PTVs) varied two- to four-fold and conformity indices were in the range of 0.3-0.6. This resulted in large variations in dose distributions to OARs as well as in treated and irradiated volumes even though the treatment plans showed good conformity to the PTVs. Potential reasons for the differences in target delineation were analysed. CONCLUSION: Considerations of the growing child and difficulties in interpretation of the radiotherapy information in the treatment protocols were identified as reasons for the variation. As a result, clarified translated detailed radiotherapy guidelines for paediatric/adolescent patients have been recognised as a way to reduce this variation.