Adaptive Staged-Dose Gamma Knife Radiosurgery for the Treatment of Large Brain Metastases: Report of 40 Consecutive Cases and Analysis of Literature.

Background: Brain metastases are the most common brain tumors, being one of the most frequent neurological complications of systemic cancer and an important cause of morbidity and mortality. Stereotactic radiosurgery is efficacious and safe in the treatment of brain metastases, with good local control rates and low adverse effects rate. Large brain metastases present some issues in balancing local control and treatment-related toxicity. Objective: Demonstrating adaptive staged-dose Gamma Knife radiosurgery (ASD-GKRS) being a safe and effective treatment for large brain metastases. Materials and Methods: We retrospectively analyzed our series of patients treated with two-stage Gamma Knife radiosurgery for large brain metastases in [BLINDED], between February 2018 and May 2020. Results: Forty patients with large brain metastases underwent adaptive staged-dose Gamma Knife radiosurgery, with median prescription dose of 12 Gy and a median interval between stages of 30 days. At three-month follow-up, the survival rate was 75.0% with a local control rate of 100%. At six-month follow-up, the survival rate was 75.0% with a local control rate of 96.7%. The mean volume reduction was 21.81 cm3 (16.76-26.86; 95% CI). The difference between baseline volume and six-month follow-up volume was statistically significant. Conclusions: Adaptive staged-dose Gamma Knife radiosurgery is a safe, non-invasive and effective treatment for brain metastases, with a low rate of side effects. Large prospective trials are needed to strengthen data obtained about the effectiveness and safety of this technique in managing large brain metastases.

Almost one year of COVID-19 pandemic: how radiotherapy centers have counteracted its impact on cancer treatment in Lombardy, Italy. CODRAL/AIRO-L study.

Lombardy has represented the Italian and European epicenter of the coronavirus disease 2019 (COVID-19) pandemic. Although most clinical efforts within hospitals were diverted towards the care of virally infected patients, therapies for patients with cancer, including radiotherapy (RT), have continued. During both the first and second pandemic waves, several national and regional organizations provided Italian and Lombardian RT departments with detailed guidelines aimed at ensuring safe treatments during the pandemic. The spread of infection among patients and personnel was limited by adopting strict measures, including triage procedures, interpersonal distance, and adequate implementation of personal protective equipment (PPE). Screening procedures addressed to both the healthcare workforce and patients, such as periodic nasopharyngeal swabs, have allowed the early identification of asymptomatic or pauci-symptomatic COVID-19 cases, thus reducing the spread of the infection. Prevention of infection was deemed of paramount importance to protect both patients and personnel and to ensure the availability of a minimum number of staff members to maintain clinical activity. The choice of treating COVID-19-positive patients has represented a matter of debate, and the risk of oncologic progression has been weighted against the risk of infection of personnel and other patients. Such risk was minimized by creating dedicated paths, reserving time slots, applying intensified cleaning procedures, and supplying personnel and staff with appropriate PPE. Remote working of research staff, medical physicists, and, in some cases, radiation oncologists has prevented overcrowding of shared spaces, reducing infection spread.

MRI only in a patient with prostate cancer with bilateral metal hip prostheses: case study.

OBJECTIVE: To outline a practical method of performing prostate cancer radiotherapy in patients with bilateral metal hip prostheses with the standard resources available in a modern general hospital. The proposed workflow is based exclusively on magnetic resonance imaging (MRI) to avoid computed tomography (CT) artifacts. CASE DESCRIPTION: This study concerns a 73-year-old man with bilateral hip prostheses with an elevated risk prostate cancer. Magnetic resonance images with assigned electron densities were used for planning purposes, generating a synthetic CT (sCT). Imaging acquisition was performed with an optimized Dixon sequence on a 1.5T MRI scanner. The images were contoured by autosegmentation software, based on an MRI database of 20 patients. The sCT was generated assigning averaged electron densities to each contour. Two volumetric modulated arc therapy plans, a complete arc and a partial one, where the beam entrances through the prostheses were avoided for about 50° on both sides, were compared. The feasibility of matching daily cone beam CT (CBCT) with MRI reference images was also tested by visual evaluations of different radiation oncologists. CONCLUSIONS: The use of magnetic resonance images improved accuracy in targets and organs at risk (OARs) contouring. The complete arc plan was chosen because of 10% lower mean and maximum doses to prostheses with the same planning target volume coverage and OAR sparing. The image quality of the match between performed CBCTs and MRI was considered acceptable. The proposed method seems promising to improve radiotherapy treatments for this complex category of patients.

Back to (new) normality-A CODRAL/AIRO-L survey on cancer radiotherapy in Lombardy during Italian COVID-19 phase 2.

BACKGROUND: Italy experienced one of the world's severest COVID-19 outbreak, with Lombardy being the most afflicted region. However, the imposed safety measures allowed to flatten the epidemic curve and hence to ease the restrictions and inaugurate, on the 4th of May 2020, the Italian phase (P) 2 of the pandemic. The present survey study, endorsed by CODRAL and AIRO-L, aimed to assess how radiotherapy (RT) departments in Lombardy have dealt with the recovery. MATERIALS AND METHODS: A questionnaire dealing with the management of pandemic was developed online and sent to all CODRAL Directors on the 10th of June 2020. Answers were collected in full anonymity one week after. RESULTS: All the 33 contacted RT facilities (100%) responded to the survey. Despite the scale of the pandemic, during P1 14 (42.4%) centres managed to safely continue the activity (≤ 10% reduction). During P2, 10 (30.3%) centres fully recovered and 14 (42.4%) reported an increase. Nonetheless, 6 (18.2%) declared no changes and, interestingly, 3 (9.1%) reduced activities. Overall, 21 centres (63.6%) reported suspected or positive cases within healthcare workforce since the beginning of the pandemic. Staff units were quarantined in 19 (57.6%) and 6 (18.2%) centres throughout P1 and P2, respectively. In the two phases, about two thirds centres registered positive or suspected cases amongst patients. CONCLUSION: The study revealed a particular attention to anti-contagion measures and a return to normal or even higher clinical workload in most RT centres in Lombardy, necessary to carry out current and previously deferred treatments.

Gamma Knife Radiosurgery for Treatment of Brain Metastases during the COVID-19 Outbreak.

INTRODUCTION: The WHO declared 2019 severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) a public health emergency of international concern. The National and Regional Health System has been reorganized, and many oncological patients died during this period or had to interrupt their therapies. This study summarizes a single-centre experience, during the COVID-19 period in Italy, in the treatment of brain metastases with Gamma Knife stereotactic radiosurgery (GKRS). METHODS: We retrospectively analysed our series of patients with brain metastases who underwent GKRS at the Niguarda Hospital from February 24 to April 24, 2020. RESULTS: We treated 30 patients with 66 brain metastases. A total of 22 patients came from home and 8 patients were admitted to the emergency room for urgent neurological symptoms. Duration of stay was limited to 0-1 day in 17 patients. We chose to treat a cluster of 9 patients, whose greater lesion exceeded 10 cm3, with 2-stage modality GKRS to minimize tumour recurrence and radiation necrosis. CONCLUSION: Due to the COVID-19 pandemic, the whole world is at a critical crossroads about the use of health care resources. During the COVID-19 outbreak, the deferral of diagnostic and therapeutic procedures and a work backlog in every medical specialty are the natural consequences of reservation of resources for COVID-19 patients. GKRS improved symptoms and reduced the need for open surgeries, allowing many patients to continue their therapeutic path and sparing beds in ICUs. Neurosurgeons have to take into account the availability of stereotactic radiosurgery to reduce hospital stay, conciliating safety for patients and operators with the request for health care coming from the oncological patients and their families.

Proportional incidence of interval colorectal cancer in a large population-based faecal immunochemical test screening programme.

BACKGROUND: The European guidelines for quality assurance in colorectal cancer (CRC) screening recommend that interval cancer rate be expressed as a proportion of background incidence rate. AIM: To determine the crude and adjusted proportional incidence of interval CRC in an Italian regional two-yearly faecal immunochemical test (FIT) screening programme. METHODS: The programme (year of implementation, 2005) is targeted at over 1,000,000 people aged 50-69 years. The test is a one-sample OC-Sensor (Eiken Chemical Co., Tokyo, Japan). The study covered one-third of the regional area. Excerpts of 434,295 eligible negative FIT records dated 2005-2012 from 193,193 subjects were retrieved from the regional CRC screening data warehouse. By 31 December 2013, the cohort accumulated 198,302 man-years and 235,370 woman-years. Interval CRCs were identified by record-linkage with the local population-based cancer registry. Their number was divided by the expected number, estimated with age-period-cohort models, to obtain the proportional incidence. RESULTS: The proportional incidence of interval CRC for men and women was, respectively, 0.06 (95% confidence interval (CI), 0.04-0.09) and 0.17 (95% CI, 0.13-0.23) in the first interval year, and 0.21 (95% CI, 0.16-0.26) and 0.28 (95% CI, 0.22-0.36) in the second year. CONCLUSIONS: The results were acceptable and in line with previous studies.

Sensitivity of CE-MRI in detecting local recurrence after radical prostatectomy.

AIM: The aim of our study was to evaluate the sensitivity of contrast-enhanced magnetic resonance (CE-MR) with phased array coil in the diagnosis of local recurrence in patients with prostate cancer after radical prostatectomy and referred for salvage radiotherapy (SRT). MATERIALS AND METHODS: This retrospective study included 73 patients treated with SRT after radical prostatectomy in the period between September 2006 and November 2017. All patients performed a CE-MRI with phased array coil before the start of SRT. A total of 213 patients treated at the ASST Grande Ospedale Metropolitano Niguarda in the period between September 2006 and November 2017 with SRT after radical prostatectomy were reviewed. Seventy-three patients with a CE-MRI with phased array coil of the pelvis before the start of SRT were included in the present study. RESULTS: At imaging review, recurrence local recurrent disease was diagnosed in 48 of 73 patients. By considering as reference standard the decrease in prostate-specific antigen (PSA) value after radiotherapy, we defined: 41 true positive (patients with MRI evidence of local recurrence and PSA value decreasing after SRT), 7 false positive (patients with MRI evidence of local recurrence without biochemical response after SRT), 3 true negative (patients without MRI evidence of local recurrence and stable or increased PSA value after SRT) and 22 false negative (patients without MRI evidence of local recurrence and PSA value decreasing after SRT) cases. The sensitivity values were calculated in relation to the PSA value before the start of treatment, obtaining a value of 74% for PSA above 0.2 ng/mL. CONCLUSION: The sensitivity of CE-MRI in local recurrence detection after radical prostatectomy increases with increasing PSA values. CE-MRI with phased array coil can detect local recurrences after radical prostatectomy with a good sensitivity in patients with pre-RT PSA value above 0.2 ng/mL.

Radiotherapy for oligometastatic cancer: a survey among radiation oncologists of Lombardy (AIRO-Lombardy), Italy.

AIMS: To evaluate the use of radiotherapy (RT) for oligometastatic cancer (OMC) among radiation oncologists in Lombardy, Italy. METHODS AND STUDY DESIGN: A survey with 12 items regarding data of 2016 was sent to all 34 Lombardy RT centers. The survey included six general items and six specific items regarding patient/disease/treatment characteristics. RESULTS: Thirteen centers answered the survey (38%). All centers responded to general items and 12 centers submitted patient/disease/treatment data. General items The majority of centers (8/13) consider OMC if metastases number is less than 5. The most commonly prescribed dose/fraction is 5-10 Gy (8/13) using schedules of 3-5 fractions (11/13). Patient data items A total of 15.681 patients were treated in 2016 with external beam RT in 12 responding centers, and 1.087 patients were treated for OMC (7%). Primary tumor included lung, prostate, breast, colorectal and other malignancies in 33%, 21%, 12%, 9% and 25% of all OMC patients, respectively. Brain, lymph node, lung, bone, liver and others were the most common treated sites (24%, 24%, 22%, 17%, 8% and 5%, respectively). One and more than one metastasis were treated in 75 and 25% of patients, respectively. The vast majority of patients (95%) were treated with image-guided intensity-modulated RT or stereotactic RT. CONCLUSIONS: Seven percent of all RT patients in Lombardy are treated for OMC. Extreme hypofractionation and high-precision RT are commonly employed. The initiative of multicenter and multidisciplinary collaboration has been undertaken in order to prepare the platform for prospective and/or observational studies in OMC.

Equipment, staffing, and provision of radiotherapy in Lombardy, Italy: Results of three surveys performed between 2012 and 2016.

INTRODUCTION:: Several efforts are being implemented at the European level to measure provision of up-to-date radiation treatments across the continent. METHODS:: A snapshot survey involving all radiation oncology centers within Lombardy, Italy, was performed in 2012 and repeated in 2014 and 2016, in cooperation with regional governmental officers. Centers were asked to provide detailed information concerning all individual patients being treated on the index day, and to report data on available local resources. RESULTS:: We observed an increase in the number of centers and of megavoltage units (MVU) (from 76 to 87, i.e., 8.7 MVU per million inhabitants in 2016). Mean number of MVU per center was 2.5. Average age of MVU increased from 5.3 to 7.5 years and patients on the waiting list also increased. Conformal 3D radiotherapy (RT) treatments decreased from 56% to 42% and were progressively replaced by intensity-modulated RT treatments (from 39% to 49%). Waiting times were overall satisfactory. Radiation oncologists treated on average 152 and radiation therapists 100 RT courses per year. Average reimbursement per course was €4,879 (range €2,476-€8,014). CONCLUSIONS:: The methodology of snapshot survey proved feasible and provided valuable information about radiation oncology provision and accessibility in Lombardy.

Easy screening for everyone.

OBJECTIVES: to increase participation of immigrant women at cervical cancer screening programmes. DESIGN: pre-post study to evaluate the efficacy of recall by phone call in immigrant women. SETTING AND PARTICIPANTS: 6,133 immigrant women in Cesena (Emilia-Romagna Region, Northern Italy) who have never made a Pap test in the last three years. MAIN OUTCOME MEASURES: increment of percentage of immigrant women who participated in cervical cancer screening. RESULTS: the recall by phone call and counselling by linguistic mediators to immigrant women from high-pressure to migrate Country moved their participation percentage to cervical screening programmes from 46% (period 2006-2008) to 56% (period 2011-2013). Linguistic mediators contacted 2,131 of these women and they verified that 1,437 of them have not made a Pap test in the last three years. These women were suggested to do the Pap test and 555 of them (39%) did it; these tests cost about 25 euros each for counselling and telephone recall. Pap tests, colposcopies, and histology results permitted to find out and treat: 2 cervical dysplasia of grade I (mild), 3 of grade II (moderate), and 3 of grade III (severe). These 6 women with moderate or severe dysplasia had an average age of 37 years and have never done a Pap test. The cost to find out these cases of moderate or severe dysplasia was about 2,000 euros each. CONCLUSION: the recall phone call and counselling by linguistic mediators is effective and low cost to increase the participation of foreign women in screening programmes.

Long-Term Effects of Radiotherapy on Arterial Stiffness in Breast Cancer Women.

Radiotherapy for breast cancer may expose heart and vessels to late radiation-induced complications. Although recent technical progress in radiation therapy (RT) has been associated with drastic reduction in cardiovascular (CV) mortality, the prolonged life expectancy of patients with cancer requires CV evaluation for many years. The aim of our study was to evaluate local changes in vascular and cardiac function because of previous breast RT. We enrolled 43 patients treated with RT 15 years ago for breast cancer. CV risk factors and atherosclerotic carotid damage were investigated in all women. We divided patients into 2 groups: R (n = 25) treated to right breast and L (n = 18) to left breast. All subjects were submitted to standard echocardiography and functional arteries evaluation by carotid-radial pulse-wave velocity (crPWV; Complior) and AIx (Sphygmocor; Atcor Medical). Global mean age was 69.5 ± 8 years old. CV risk factors were equally allocated in 2 groups. No patients had history of cardiac or artery disease. R had a significantly increased crPWV (9.9 ± 1.4 vs 8.9 ± 1.1, p = 0.001) on right arm compared with left arm, and in L group, crPWV was similarly higher on the left arm than on right arm (9.6 ± 1.5 vs 8.9 ± 1.4, p = 0.011). AIx was significantly increased in the ipsilateral arm only in L (32.1 ± 7.6 vs 28.3 ± 6.8, p = 0.05). Central blood pressure estimation was not different in the right and left arms. No correlations were found with hormone therapy or chemotherapy. Our data show a local arterial stiffening because of radiation that can be involved in increased CV risk in breast cancer-treated patients.

Cervical cancer screening in immigrant women in Italy: a survey on participation, cytology and histology results.

Cervical cancer screening programmes in Italy actively invite all 25-64-year-old resident women for the Pap test every 3 years irrespective of their citizenship. Immigrant women come from countries where screening is absent or poorly implemented and the prevalence of human papillomavirus is often high. These women therefore have significant risk factors for cervical cancer. The Italian Group for Cervical Cancer Screening promoted a survey of all the screening programmes on the participation and the positivity and detection rates in Italian and foreign women in 2009-2011. Aggregated data for participation, cytology results, compliance with colposcopy and histology results were collected, distinguishing between women born in Italy and abroad. All comparisons were age adjusted. Forty-eight programmes out of 120 participated in the immigrant survey, with 3 147 428 invited and 1 427 412 screened Italian women and 516 291 invited and 205 948 screened foreign women. Foreign women had a slightly lower participation rate compared with Italians (39.9 vs. 45.4%), whereas compliance with colposcopy was similar (90%). Foreigners showed a higher risk of pathological findings than Italians: cytology positivity [relative risk (RR)=1.25, 95% confidence interval (CI) 1.24-1.27] and detection rate for cervical intraepithelial neoplasia grade 2 (CIN2) (RR=1.39, 95% CI 1.31-1.47), CIN3 (RR=2.07, 95% CI 1.96-2.18) and cancer (RR=2.68, 95% CI 2.24-3.22). The ratio between cancer and CIN was higher in immigrants (0.06 vs. 0.04, P<0.01). Foreign women had a higher risk of cervical precancer and cancer. Because of their high risk and because opportunistic screening does not cover this often disadvantaged group, achieving high participation in screening programmes for foreigners is critical to further reducing the cervical cancer burden in Italy.

Colonoscopic surveillance of first-degree relatives of colorectal cancer patients in a faecal occult blood screening programme.

BACKGROUND: In some Italian areas, colonoscopic surveillance of first-degree relatives (FDRs) of colorectal cancer (CRC) patients is provided as a part of local population-based faecal occult blood test (FOBT) screening programmes. The objective of the present study was to assess the feasibility and early results of this surveillance model. METHODS: Data from district screening centres were used to evaluate the process of identification and selection of eligible FDRs (residence in the Emilia-Romagna Region, age 40-75 years, no recent colonoscopy) of screen-detected CRC patients and the detected prevalence of disease. The probability for an FDR to undergo colonoscopy and to be diagnosed with CRC and advanced adenoma was estimated using the Kaplan-Meier method. The sex- and age-standardised ratio of detected prevalence to that expected based on results from a colonoscopy screening study of the Italian general population was estimated. RESULTS: Between 2005 and 2011, 9319 FDRs of 2437 screen-detected CRC patients (3.8 per patient) were identified and contacted. Their likelihood of being eligible for, and accepting, colonoscopy was 0.11 (95% confidence interval: 0.11-0.12). Among the 926 subjects undergoing colonoscopy, the prevalence of previous negative screening FOBT was 63%. Eleven CRCs (1.2%) and 100 advanced adenomas (10.8%) were detected. The standardised ratio of detected prevalence to that expected was 0.91 (95% confidence interval: 0.19-2.66) for CRC and 1.48 (1.04-2.05) for advanced adenoma. CONCLUSIONS: The procedure of selection of FDRs was extremely ineffective. Due to previous negative screening tests, the prevalence of disease was less than expected. A population-based FOBT screening programme is a highly unsuitable setting for the provision of surveillance to FDRs of CRC patients.

Set-up errors and planning target volume margins in head and neck cancer radiotherapy: a clinical study of image guidance with on-line cone-beam computed tomography.

BACKGROUND: Set-up errors represent a source of uncertainty in head and neck (H&N) cancer radiotherapy. The present study evaluated set-up accuracy with the use of cone-beam computed tomography (CBCT) in order to establish the proper clinical target volume (CTV) to planning target volume (PTV) margins to be adopted. METHODS: Local set-up accuracy was analysed for 44 H&N cancer patients since the implementation of CBCT. An on-line correction protocol was adopted, with the first 3 scans used to correct systematic errors with a 3-mm action level. The overall mean displacement (M), the population systematic (Σ) and random (σ) errors and the 3D vector length were calculated. PTV margins were calculated according to the van Herk formula (2.5Σ + 0.7σ). RESULTS: A total of 420 CBCT scans were analysed. A systematic correction was needed in 43% of patients. The value of M was <1 mm in all directions; the values of Σ and σ ranged over 1-1.2 and 1.4-1.9 mm, respectively. Pre-correction PTV margins were 3.48, 4.08 and 4.33 mm along the 3 axes. The PTV margins calculated after online correction were <2.5 mm in all directions. CONCLUSIONS: Kilovoltage CBCT is effective in evaluating set-up accuracy in H&N patients. CTV-PTV margins of 5 mm are safe and are currently adopted at our centre; however, some special situations, such as re-irradiation or the close proximity of organs at risk and high-dose regions, could benefit from daily image registration and lower (i.e., 3 mm) margins.

Critical analysis of locoregional failures following intensity-modulated radiotherapy for nasopharyngeal carcinoma.

AIM: To analyze the patterns of locoregional failure following intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC) at our institution, as part of an internal quality assurance program. We aimed to investigate the potential existence of a correlation between any part of the IMRT process and clinical outcome. METHODS & MATERIALS: A total of 106 non-metastatic NPC patients consecutively treated with IMRT (with or without chemotherapy) were analyzed. Radiotherapy was administered using a sequential or simultaneous integrated boost approach at the total prescribed dose of 66-70 Gy (2.00-2.12 Gy per fraction). MRI studies of recurrences were recorded with the planning computed tomography studies to identify volume of failure. Recurrence-related characteristics were analyzed with respect to the original treatment. Failures were classified as 'in-field', 'marginal' or 'out-field' if at least 95, 20-95 or less than 20% of the volume of failure, respectively, was within 95% of the total prescription dose. RESULTS: With a median follow-up of 43.4 months, 5-years local control, regional control, locoregional control and overall survival rates were 87.7, 88.0, 83.5 and 81.3% respectively. A total of 21 failures were registered in 15 patients. In particular, ten failures (47.6%) were classified as 'in-field' (seven local failures and three regional failures [RFs]), nine failures (42.9%) as 'marginal' (five local failures and four RFs) and only two failures (9.5%) as 'out-field' (both RFs). The most relevant causes of failures were suboptimal target definition and target coverage as well as a longer than planned overall treatment time. CONCLUSION: IMRT determines excellent outcome in NPC patients. However, great attention in all IMRT steps is necessary to reduce potential causes of failure.

[Methods to increase participation in cancer screening programmes]. / Metodi per aumentare la partecipazione ai programmi di screening oncologici.

OBJECTIVE: to synthesize scientific evidences about methods to increase cervical, breast and colorectal cancer screening participation. METHODS: a multidisciplinary working group has been set up to define the scope of the report and to conduct the evaluation. The scope and the final evaluation have been submitted to a stakeholder committee, including the Ministry of Health, the National Screening Observatory, regional screening program coordinators, scientific societies, and Lega Italiana Lotta ai Tumori, for comments and integrations. A systematic review of the principal biomedical and social literature databases was conducted to identify experimental and observational studies, updating the existing review by Jepson and coll. (Health Technol Assess. 2000;4(14):i-vii, 1-133). RESULTS: 5900 have been identified, 900 relevant for the topic.Among those, 148 reported quantitative information on intervention efficacy, other 90 came from the previous review. Organised screening programmes, based on invitation letter or on GP involvement,were consistently effective in increasing participation compared to spontaneous screening. Interventions are classified according to their target: individual, community, test simplification, health operators, health service organization. The report presents meta-analyses on efficacy, analyses of cost-effectiveness, impact on organisation and social inequality, and ethical and legal issues, of all the intervention reported in the literature. CONCLUSIONS: there are several interventions consistently effective in any context, some of them have minimal impact on costs and health service resources.

Geometry of volumes in radiotherapy planning. A new method for a quantitative assessment.

AIMS AND BACKGROUND: The purpose of the study was to develop a general method able to quantify the mutual disposition in the 3D space of critical organs with respect to the target when these structures are designed for a radiotherapy treatment plan. To that end, we introduce the "expansion intersection histogram", a function defined as the intersection between an organ at risk and the target volume, while the target is expanded in 3D. METHODS AND STUDY DESIGN: A software was developed to calculate the expansion intersection histogram of anatomical structures exported in a DICOM format from a commercial treatment planning system. A virtual phantom with spherical and cylindrical objects arranged in different dispositions in the 3D space was created for testing the software under known conditions. RESULTS AND CONCLUSIONS: Expansion intersection histogram computation was tested against reference data derived analytically for spherical volumes, with a resulting maximum error of 0.5%. Specific geometric features derived from the expansion intersection histogram, such as the distance between a selected target and each different ideal volume included in the virtual phantom, well matched the corresponding theoretical expected values. The expansion intersection histogram was evaluated also for the anatomical structures of a real patient. Data show this method as a tool to effectively take into account the mutual disposition of each critical organ with respect to the target, summarized in characteristics of distance, shape and orientation. The expansion intersection histogram method integrates and extends other preexisting modalities for evaluating the geometrical relationships among radiotherapy volumes and could be used to improve planning optimization.

Patterns of postoperative radiotherapy for head and neck cancer in Italy: a prospective, observational study by the head and neck group of the Italian Association for Radiation Oncology (AIRO).

AIMS AND BACKGROUND: Our previous survey showed that the patterns of postoperative radiotherapy (PORT) for head and neck cancer (HNC) in Italy might be suboptimal. A prospective observational study was therefore designed to evaluate this issue in greater detail. METHODS: All radiotherapy centers involved in the HNC Working Group of the Italian Radiation Oncology Association were asked to enter into the study all patients treated with PORT during a 6-month period. RESULTS: A total of 200 patients were accrued by 24 centers from December 2008 to May 2009. Larynx (38%) and oral cavity (34%) were the most common primary sites. The median time between surgery and the start of radiotherapy was 69 days (range, 25-215 days). Seventy-nine percent of cases with no evidence of risk factors for local recurrence were treated with high-dose radiotherapy to the primary site. In about 75% of cases the pN0 neck was included in the target volume. Concomitant chemotherapy was delivered to about 60% of patients with major risk factors and 21% of patients with no risk factors. CONCLUSIONS: Three issues emerged from our study as potential targets for future investigations: the impact on clinical outcome of the interval between surgery and the start of PORT; factors driving radiation oncologists to overtreat volumes at low risk of recurrence; and problems associated with the delivery of concomitant chemotherapy.

Set-up errors analyses in IMRT treatments for nasopharyngeal carcinoma to evaluate time trends, PTV and PRV margins.

INTRODUCTION: the aims of this study were to analyze the systematic and random interfractional set-up errors during Intensity Modulated Radiation Therapy (IMRT) in 20 consecutive nasopharyngeal carcinoma (NPC) patients by means of Electronic Portal Images Device (EPID), to define appropriate Planning Target Volume (PTV) and Planning Risk Volume (PRV) margins, as well as to investigate set-up displacement trend as a function of time during fractionated RT course. MATERIAL AND METHODS: before EPID clinical implementation, an anthropomorphic phantom was shifted intentionally 5 mm to all directions and the EPIs were compared with the digitally reconstructed radiographs (DRRs) to test the system's capability to recognize displacements observed in clinical studies. Then, 578 clinical images were analyzed with a mean of 29 images for each patient. RESULTS: phantom data showed that the system was able to correct shifts with an accuracy of 1 mm. As regards clinical data, the estimated population systematic errors were 1.3 mm for left-right (L-R), 1 mm for superior-inferior (S-I) and 1.1 mm for anterior-posterior (A-P) directions, respectively. Population random errors were 1.3 mm, 1.5 mm and 1.3 mm for L-R, S-I and A-P directions, respectively. PTV margin was at least 3.4, 3 and 3.2 mm for L-R, S-I and A-P direction, respectively. PRV margins for brainstem and spinal cord were 2.3, 2 and 2.1 mm and 3.8, 3.5 and 3.2 mm for L-R, A-P and S-I directions, respectively. Set-up error displacements showed no significant changes as the therapy progressed (p>0.05), although displacements >3 mm were found more frequently when severe weight loss or tumor nodal shrinkage occurred. DISCUSSION: these results enable us to choose margins that guarantee with sufficient accuracy the coverage of PTVs and organs at risk sparing. Collected data confirmed the need for a strict check of patient position reproducibility in case of anatomical changes.

Radiobiological basis and clinical results of the simultaneous integrated boost (SIB) in intensity modulated radiotherapy (IMRT) for head and neck cancer: A review.

The simultaneous integrated boost (SIB)-IMRT technique allows the simultaneous delivery of different dose levels to different target volumes within a single treatment fraction. The most significant aspect associated with SIB-IMRT is related to the fractionation strategy, concerning two time-dose parameters: (1) the shortening of the overall treatment time (OTT); (2) the increase of fraction size (FS) to the boost volume. The SIB-IMRT technique represents, therefore, a new way to investigate the accelerated fractionation in definitive treatment of head and neck (H&N) cancers. The aims of this paper are the following: (1) to briefly review the influence of OTT and FS on H&N tumors and on acutely and late responding normal tissues; (2) to review the results of clinical studies of accelerated radiotherapy not employing IMRT in H&N cancer; (3) to review the clinical experiences of the SIB-IMRT technique and to compare the different SIB regimes in terms of radiobiological efficacy.