18F-choline PET/CT driven salvage radiotherapy in prostate cancer patients: up-date analysis with 5-year median follow-up.

PURPOSE: Salvage radiotherapy is generally considered as the standard treatment for biochemical relapse after surgery. Best results have been obtained with a PSA value < 0.5 ng/ml at relapse, while 60-66 Gy is deemed as standard total dose. Modern imaging, as dynamic-18F-choline PET/CT may identify site of recurrence, allowing dose escalation to a biological target volume. METHODS: Hundred and fifty patients showed a local relapse at dynamic-18F-choline PET/CT at time of biochemical recurrence. High-dose salvage radiotherapy was delivered up to total dose of 80 Gy to 18F-choline PET/CT positive area. Toxicity and relapse-free survival were recorded. RESULTS: Median PSA value at the beginning of salvage radiotherapy was 0.47 ng/ml (range 0.2-17.5 ng/ml). One-hundred and thirty nine patients (93%) completed salvage radiotherapy without interruptions. Acute gastrointestinal grade ≥ 2 toxicity was recorded in 13 patients (9%), acute genitourinary grade ≥ 2 toxicity in 2 patients (1.4%). One patient (0.7%) experienced late gastrointestinal grade 4 toxicity and 2 patients (1.4%) late acute genitourinary grade 3 toxicity. With a median follow-up of 63.5 months, 5 and 7-years relapse-free survival were 70% and 60.7%, respectively. CONCLUSION: With a median follow-up of 5 years the present study confirms that high-dose salvage radiotherapy to a biological target volume is feasible, with low rate of late toxicity and promising activity.

Efficacy of a Propolis-Based Syrup (FARINGEL) in Preventing Radiation-Induced Esophagitis in Locally Advanced Lung Cancer.

AIM: To evaluate the efficacy of a propolis-based syrup, FARINGEL®, in preventing radiation-induced esophagitis in locally advanced lung cancer patients. METHODS: Patients were treated with concurrent chemoradiotherapy (CRT) using involved-field radiotherapy (RT). Every patient received FARINGEL at the beginning of CRT until the first follow-up. The data of the study group were compared with the data of a control group treated without the administration of the syrup. RESULTS: Forty-five patients were enrolled. Forty-one (91.1%) completed the protocol and were evaluable for esophagitis. Grade ≥2 toxicity occurred in 9/41 patients (22%). No differences in overall toxicity were detected between the study group and the control group (n = 55, 60.9 vs. 54.5%; p = ns). Grade 2-3 esophagitis was lower in the study group in comparison with the control group (22 and 38%, respectively), but statistical significance was not reached (p = 0.09). However, the onset of grade ≥2 esophagitis was delayed in the study group compared to the control group, occurring at higher doses of RT (41.8 vs. 25.4 Gy; p < 0.001). Furthermore, the mean number of interruption days for esophagitis was lower in the study group than in the control group (0.6 ± 2.0 vs. 2.1 ± 3.6; p = 0.025). CONCLUSION: FARINGEL was well-tolerated and delayed esophagitis that was induced by CRT for locally advanced lung cancer.

Estimation of patient setup uncertainty using BrainLAB Exatrac X-Ray 6D system in image-guided radiotherapy.

The purpose of this study was to evaluate setup uncertainties for brain sites with ExacTrac X-Ray 6D system and to provide optimal margin guidelines. Fifteen patients with brain tumor were included in this study. Two X-ray images with ExacTrac X-Ray 6D system were used to verify patient position and tumor target localization before each treatment. The 6D fusion software first generates various sets of DRRs with position variations in both three translational and three rotational directions (six degrees of freedom) for the CT images. Setup variations (translation and rotation) after correction were recorded and corrected before treatment. The 3D deviations are expressed as mean ± standard deviation. The random error (Σ(σi)), systematic error (µi), and group systematic error (M(µi)) for the different X-ray were calculated using the definitions of van Herk.(1) Mean setup errors were calculated from X-ray images acquired after all fractions. There is moderate patient-to-patient variation in the vertical direction and small variations in systematic errors and magnitudes of random errors are smaller. The global systematic errors were measured to be less than 2.0 mm in each direction. Random component of all patients are smaller ranging from 0.1-0.3 mm small. The safety margin (SM) to the lateral, is 0.5 mm and 2.6 mm for van Herk(1) and Stroom et al.,(2) respectively, craniocaudal axis is 1.5 mm and 3.4 mm, respectively, and with respect to the antero-posterior axis, 2.3 mm and 3.9 mm. Daily X-ray imaging is essential to compare and assess the accuracy of treatment delivery to different anatomical locations.

The first survey on defensive medicine in radiation oncology.

PURPOSE: Defensive Medicine occurs when doctors order tests, procedures, visits or avoid high-risk patients and procedures, primarily to reduce their exposure to malpractice liability. Some medical specialities are at "high-risk" for legal argument, but no data is actually available for radiation oncology. We present here the first survey of radiation oncologists' views regarding malpractice liability and defensive medicine practice. MATERIALS AND METHODS: A three-page questionnaire was sent to 611 active radiation oncologists, members of the Italian Association of Radiation Oncology (AIRO), with questions pertaining to the incidence, nature and causes in their practice of defensive medicine. RESULTS: A total of 361 questionnaires were completed (59 % feedback). Physicians practise defensive medicine by ordering further imaging studies (39 %) or laboratory tests (35 %), referring patients to consultants (43 %) or prescribing additional medication (35 %). Approximately, 70 % declared that the climate of opinion that exists towards doctors is one of the major issues for practising defensive medicine. CONCLUSION: Although radiation oncology is generally considered a "medium/low risk" speciality for defensive medicine, the present survey reflects a widespread use of this behaviour in daily practice. Investigating which radiation oncologist categories are more prone to defensive medical behaviour can be advantageous for implementing programmes aimed at improving awareness of this phenomenon and to increase good clinical practice.

SBRT: A viable option for treating adrenal gland metastases.

The management strategy of adrenal metastases depends on different clinical situations. Adrenal metastasectomy in selected patients with isolated adrenal metastases is considered the treatment of choice, showing prolonged survival compared to chemotherapy alone. More recently, Stereotactic Body Radiation Therapy (SBRT) has emerged as an alternative local ablative treatment modality although limited data are available on the use of SBRT in treating adrenal gland metastases. Preliminary results are, however, encouraging, especially in selected patients with oligometastatic disease. We herewith review and discuss the potential role of SBRT as a local ablative treatment modality for adrenal metastases.

A clinical score, including biohumoral parameters, is a useful pretest index to discriminate pulmonary infections from radiation damage in chemoradiation-treated lung cancer patients.

To obtain an easy and prompt differential diagnosis between lower airways infections and acute radiation pneumonitis in chemoradiation lung cancer patients. From 303 patients treated, only patients with severe pulmonary symptoms were hospitalized. Clinical and radiation scores were calculated evaluating clinical, biohumoral, dosimetric parameters. Out of 36 patients hospitalized, infections and acute radiation pneumonitis were reported in 66.7% and 33.3%, respectively. Patients with clinical score ≥ 2 had an Odds Ratio of 3.4 (1.4-8.3; p = .006) to have infectious pneumonia, while radiation score was not predictive.

Fractionated stereotactic radiosurgery for patients with brain metastases.

Stereotactic radiosurgery (SRS) delivered in 2-5 fractions (multi-fraction SRS) has been employed in patients with brain metastases as an alternative to single-fraction SRS with the aim to reduce late radiation-induced toxicity while maintaining high local control rate. In the present study we have evaluated the efficacy and toxicity of multi-fraction SRS in patients with 1-3 brain metastases. Between March 2006 and October 2012, 135 patients (63 men and 72 women) with 171 brain metastases have been treated with multi-fraction SRS (3 × 9 Gy or 3 × 12 Gy). At a median follow-up of 11.4 months, 16 lesions recurred locally. The 1- and 2-year local control rates were 88 and 72 %, respectively. The 1- and 2-year survival rates were 57 and 25 %, and respective distant failure rates were 52 and 73 %. Seventy-eight percent of patients succumbed to their extracranial disease and 22 % died of progressive intracranial disease. Multivariate analysis showed that melanoma histology was predictive of local failure (p = 0.02; HR 6.1, 95 % CI 1.5-24). Specifically, the 1-year local control rates were 68 % for melanoma, 92 % for breast carcinoma, and 88 % for NSCLC, respectively. Stable extracranial disease (p = 0.004) and Karnofsky performance status (p = 0.01) were predictive of longer survival. Radiologic changes suggestive of radionecrosis occurred in 12 (7 %) out of 171 lesions, with an actuarial risk of 9 % at 1 year and 17 % at 2 years, respectively. In conclusion, multi-fraction SRS appears to be an effective and safe treatment modality for brain metastases. It may represent an alternative to single-dose SRS for patients with large lesions or lesions located near critical structures.

Long-Term Results of a Prospective Phase 2 Study on Volume De-Escalation in Neoadjuvant Chemoradiotherapy of Rectal Cancer.

PURPOSE: In the current study, we evaluated whether neoadjuvant chemoradiotherapy with reduced treatment volumes due to the exclusion of elective pelvic nodal irradiation is a feasible strategy for selected patients with locally advanced rectal cancer. METHODS AND MATERIALS: Patients with T2 low-lying/T3, N0-N1 rectal lesions without evidence of disease in the lateral lymph nodes were prospectively recruited. All patients underwent pretreatment testing, including computed tomography imaging of the chest, abdomen, and pelvis with intravenous contrast, pelvic magnetic resonance imaging with intravenous contrast, and 18-fluorodeoxyglucose positron emission/computed tomography. The clinical target volume included the primary tumor and the mesorectum with vascular supply containing the perirectal and presacral nodes, with the upper border at the S2/S3 interspace. The total radiation dose was 50.4 Gy, and fluoropyrimidine-based chemotherapy was associated concomitantly. The primary endpoint of the study was the reduction of gastrointestinal (GI) toxicity, and the secondary endpoints were pathologic complete response, local control, overall survival, and disease-free survival. RESULTS: Fifty-two patients (30 men, 22 women) with a median age of 67 years (range, 45-85 years) were enrolled in the study. Acute grade 3 GI toxicity was 7.6%, and there were no cases of grade 4 toxicity. Three patients (5.7%) developed a local recurrence. No relapse occurred in the lateral lymph nodes. The local control rate at 5 years was 96.1%. With a median follow-up time of 72.9 months (range, 2.5-127.6 months), the 3- and 5-year overall survival rates were 89.4% and 87%, respectively. The 3- and 5-year disease-free survival rates were 82.4% and 82.4%, respectively. CONCLUSIONS: De-escalation of radiation therapy target volume reduces GI side effects without compromising efficacy in patients with rectal cancer. These results cannot be clearly extended to high-risk disease and need further evaluation in future randomized trials.

Resilience in Radiotherapy Services During the COVID-19 Emergency: Collaboration Between the Regional Radiation Oncology Departments of Lazio, Abruzzo and Molise.

AIM: Radiation therapy is a cornerstone of oncological treatment and oncological patients show greater risk of developing complications related to COVID-19 infection. Stringent social restrictions have ensured a significant reduction in the spread of the virus, but also gave rise to a number of critical issues for radiation oncology wards. For this reason, the Directors of the Radiation Oncology Departments (RODs) of Lazio, Abruzzo and Molise regions shared their experience and ideas in order to create a common document that may assist in facing the negative impacts of the pandemic on radiation oncology wards and patients. PATIENTS AND METHODS: The study was conducted according to the Estimate-Talk-Estimate method. Five issues were proposed and rated. Among approved issues, statements were proposed anonymously, then harmonized and finally voted on according to a Likert scale from 1 to 9. Those for which an agreement of 7-9 was observed were finally approved. RESULTS: The document was developed with 42 statements dealing about safety measures for patients and staff, organization of clinical and work activities, usage of Information Technology systems for meetings/smart working. An agreement was recorded for 34 statements. CONCLUSION: This document sets out some recommendations for RODs and can provide valuable management information for Oncological Radiotherapy wards.

Delayed surgery after radio-chemotherapy for rectal adenocarcinoma is protective for anastomotic dehiscence: a single-center observational retrospective cohort study.

Ideal time interval between end of neoadjuvant radio-chemotherapy (NRCT) and surgery for rectal cancer is debated. Effect that different time intervals have on postoperative complications with particular regard to anastomotic dehiscence (AD) was evaluated on 167 patients who underwent surgery after long-course NRCT. Three different time intervals were considered: (0-42; 43-56; > 57 days). A time interval > 57 days was significantly protective for AD (p = 0.04, Odds ratio = 0.35; 95% CI 0.1254-0.9585) without influence on early oncological outcomes. Optimal time interval after end of NRCT and surgery may help achieving the best pathological response with lowest postoperative morbidity.Trial registration number: Clinical Trial. Gov NCT04013347. https://clinicaltrials.gov/ct2/results?cond=&term=NCT04013347&cntry=&state=&city=&dist= ).

Design and evaluation of a methodology to perform personalized visual biofeedback for reducing respiratory amplitude in radiation treatment.

A methodology to perform personalized visual biofeedback aimed to the reduction of respiratory amplitude is here proposed. A custom-made software allows to adapt the biofeedback parameters to a patient's respiratory pattern by calculating a limiting range for respiratory amplitude obtained from data acquired during free breathing. The proposed methodology has been tested on ten healthy volunteers and on five lung cancer patients undergoing radiotherapy treatment. The protocol for volunteers consisted of 3 min of data acquisition during the subject's free breathing, 2 min of visual biofeedback within the limits, and 3 min of free breathing. The patients' free breathing was acquired in 3 min and the visual biofeedback performed during all the sessions of the radiotherapy treatment, i.e., an average of eight sessions and an average total treatment time of 2000 s each patient. All the volunteers and three patients of the five found the protocol comfortable. The settlement time needed for considering the limiting range stabilized during free breathing has been calculated as 120 +/- 10 s (p < 0.05). During visual biofeedback the baseline shift was removed and the average respiratory amplitude was reduced by about 40% for all the subjects. The variability of the breathing amplitude remained unaltered during biofeedback. Eight volunteers and three patients remained within the limiting range for more than 90% of the biofeedback period; all subjects remained within the limiting range for more than 80% of the biofeedback period. During the biofeedback period both groups, volunteers and patients, showed a significant increase in breathing frequency which was mostly doubled. Patients with shallow breathing performed comfortably the biofeedback.

Integration between in vivo dosimetry and image guided radiotherapy for lung tumors.

The article reports a feasibility study about the potentiality of an in vivo dosimetry method for the adaptive radiotherapy of the lung tumors treated by 3D conformal radiotherapy techniques (3D CRTs). At the moment image guided radiotherapy (IGRT) has been used for this aim, but it requires taking many periodic radiological images during the treatment that increase workload and patient dose. In vivo dosimetry reported here can reduce the above efforts, alerting the medical staff for the commissioning of new radiological images for an eventual adaptive plan. The in vivo dosimetry method applied on 20 patients makes use of the transit signal St on the beam central axis measured by a small ion chamber positioned on an electronic portal imaging device (EPID) or by the EPID itself. The reconstructed in vivo dosimetry at the isocenter point Diso requires a convolution between the transit signal St and a dose reconstruction factor C that essentially depends on (i) tissue inhomogeneities along the beam central axis and (ii) the in-patient isocenter depth. The C factors, one for every gantry angle, are obtained by processing the patient's computed tomography scan. The method has been recently applied in some Italian centers to check the radiotherapy of pelvis, breast, head, and thorax treatments. In this work the dose reconstruction was carried out in five centers to check the Diso in the lung tumor during the 3D CRT, and the results have been used to detect the interfraction tumor anatomy variations that can require new CT imaging and an adaptive plan. In particular, in three centers a small ion chamber was positioned below the patient and used for the St measurement. In two centers, the St signal was obtained directly by 25 central pixels of an a-Si EPID, equipped with commercial software that enabled its use as a stable detector. A tolerance action level of +/- 6% for every checked beam was assumed. This means that when a difference greater than 6% between the predicted dose by the treatment planning system, Diso,TPS, and the Diso was observed, the clinical action started to detect possible errors. 60% of the patients examined presented morphological changes during the treatment that were checked by the in vivo dosimetry and successively confirmed by the new CT scans. In this work, a patient that showed for all beams Diso values outside the tolerance level, new CT scans were commissioned for an adaptive plan. The lung dose volume histograms (DVHs) for a Diso,TPs=2 Gy for fraction suggested the adaptive plan to reduce the dose in lung tissue. The results of this research show that the dose guided radiotherapy (DGRT) by the Diso reconstruction was feasible for daily or periodic investigation on morphological lung tumor changes. In other words, since during 3D CRT treatments the anatomical lung tumor changes occur frequently, the DGRT can be well integrated with the IGRT.

Molecularly targeted therapy and radiotherapy in the management of localized gastrointestinal stromal tumor (GIST) of the rectum: a case report.

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal tract. The main treatment for localized gastrointestinal stromal tumors is surgical resection. These tumors respond poorly to conventional cytotoxic chemotherapy agents and to radiotherapy. Imatinib mesylate, a small-molecule kinase inhibitor, has proved useful in the treatment of recurrent or metastatic GISTs and is now being tested in the adjuvant and neoadjuvant setting. The role of radiotherapy in the management of patients with GIST is currently restricted to symptomatic palliation. We present the case of a 54-year-old man affected by rectal GIST extending to the anal canal, with constipation, hematochezia, and anal pain. He received imatinib, 400 mg orally per day, for a week before and during radiation therapy. Irradiation was delivered to the gross tumor volume by 3D conformal therapy. The planned total dose was 50.4 Gy in fractions of 1.8 Gy daily. We observed a partial clinical response 3 weeks after the end of combination treatment. The patient then underwent a sphincter-saving surgical procedure. There was no perioperative morbidity and a complete pathological response was obtained. At the present time, the role of radiotherapy in the management of patients with GIST is restricted to symptomatic palliation. The introduction of molecularly targeted therapy combined with radiation therapy could improve the outcomes for patients diagnosed with GIST.

Implant breast reconstruction after salvage mastectomy in previously irradiated patients.

The most common surgical approach in case of local tumor recurrence after quadrantectomy and radiotherapy is salvage mastectomy. Breast reconstruction is the subsequent phase of the treatment and the plastic surgeon has to operate on previously irradiated and manipulated tissues. The medical literature highlights that breast reconstruction with tissue expanders is not a pursuable option, considering previous radiotherapy a contraindication. The purpose of this retrospective study is to evaluate the influence of previous radiotherapy on 2-stage breast reconstruction (tissue expander/implant). Only patients with analogous timing of radiation therapy and the same demolitive and reconstructive procedures were recruited. The results of this study prove that, after salvage mastectomy in previously irradiated patients, implant reconstruction is still possible. Further comparative studies are, of course, advisable to draw any conclusion on the possibility to perform implant reconstruction in previously irradiated patients.

Histologic transformation to small-cell lung cancer following gefitinib and radiotherapy in a patient with pulmonary adenocarcinoma.

INTRODUCTION: Targeted therapies against epidermal growth factor receptor (EGFR) have revolutionized the treatment of a subset of lung adenocarcinomas that have EGFR-activating mutations; however, all patients treated with EGFR tyrosine kinase inhibitors (TKIs) ultimately develop resistance. Histologic transformation of EGFR-mutant adenocarcinoma to small cell lung cancer (SCLC) is a resistance mechanism rarely reported in the literature. CASE PRESENTATION: We describe the case of a woman with metastatic lung cancer adenocarcinoma with mutated EGFR with an initial response to gefitinib and radiation therapy, who progressed after 18 months due to the development of a resistance mechanism. The new biopsy performed after progression highlighted histologic transformation to SCLC, while maintaining the original EGFR mutation. CONCLUSIONS: To better identify patients who progress after TKIs and radiation therapy, it is important to perform tumor rebiopsy and collect data to study mechanisms of acquired EGFR TKI resistance.

Hypofractionated radiotherapy with concomitant boost for breast cancer: a dose escalation study.

METHODS:: Patients with breast cancer with pathological stage pT 1-2 and at least one risk factor for local recurrence such as N1 disease, lymphovascular invasion, extensive intraductal component, close margins, non-hormone sensitive disease, grading G3 were enrolled. Patients were treated with hypofractionated RT to whole breast with a dose of 40.05 Gy in 15 fractions. The dose was escalated to the tumour bed through a daily concomitant boost technique at three dose levels: 48 Gy (3.2 Gy/die), 50.25 Gy(3.35 Gy/die) and 52.5 Gy (3.5 Gy/die). Dose escalation to a higher step was carried out if all patients of the lower dose had completed the treatment without dose limiting toxicity (DLT). Skin toxicity, cosmetic evaluation and quality of life was evaluated at baseline, at treatment end and at 3 and 12 months after RT end. RESULTS:: Three patients for each dose level were enrolled. No DLT occurred. The maximum toxicity collected during RT was G2 skin toxicity in 3 (33.3%) patients, one for each dose level. No G2 toxicity at 3 and 12 months was collected. At median follow up of 21.8 months (range: 13.5 - 40.9 months), no G2 late toxicity was recorded. CONCLUSION:: The 3 week course of post-operative RT with dose escalation to the tumour bed to 52.5 Gy has been achieved without dose limiting toxicities and can be tested in Phase II trials. ADVANCES IN KNOWLEDGE:: In our study, we tested the highest dose level to the tumour bed ever reported in studies using accelerated hypofractionation with concomitant boost in high risk patients.

Novel prognostic groups in thymic epithelial tumors: assessment of risk and therapeutic strategy selection.

PURPOSE: To assess the role of multimodality treatment on patients with thymic epithelial tumors (TETs) (i.e., thymomas and thymic squamous cell carcinoma) and to define the prognostic classes according to the Masaoka and World Health Organization histologic classification systems. METHODS AND MATERIALS: Primary surgery was the mainstay of therapy. Extended thymectomy was performed in all cases. The cases were primarily staged according to the Masaoka system. Adjuvant radiotherapy was given to patients diagnosed with Masaoka Stage II, III, and IVA TET. Adjuvant chemotherapy was administered in selected cases. RESULTS: We reviewed the records of 120 patients with TETs, with a mean follow-up of 13.8 years. Of the 120 patients, 98 (81.6%) received adjuvant radiotherapy. Of these 98 patients, Grade 1-2 pulmonary or esophageal toxicity was acute in 12 (12.2%) and late in 8 (8.2%). The median overall survival was 21.6 years. Of the 120 patients, 106 were rediagnosed and reclassified according to the World Health Organization system, and the survival rate was correlated with it. Three different prognostic classes were defined: favorable, Masaoka Stage I and histologic grade A, AB, B1, B2 or Masaoka Stage II and histologic grade A, AB, B1; unfavorable, Stage IV disease or histologic grade C or Stage III and histologic grade B3; intermediate, all other combinations. The 10- and 20-year survival rate was 95% and 81% for the favorable group, 90% and 65% for the intermediate group, and 50% and 0% for the unfavorable group, respectively. Local recurrence, distant recurrence, and tumor-related deaths were also evaluated. CONCLUSION: The analysis of our experience singled out three novel prognostic classes and the assessment of risk identified treatment selection criteria.

Randomized, multicenter, phase IIb study of preoperative chemoradiotherapy in T3 mid-distal rectal cancer: raltitrexed + oxaliplatin + radiotherapy versus cisplatin + 5-fluorouracil + radiotherapy.

PURPOSE: To prospectively compare the rates of pathologic response, acute toxicity, and sphincter preservation with two different schedules of preoperative chemoradiotherapy in patients with cT3 mid-distal rectal cancer. METHODS AND MATERIALS: Patients with cT3 and/or N+ resectable rectal carcinoma were randomized to receive one of the two following chemoradiotherapy regimens: cisplatin, 5-fluorouracil, and radiotherapy (PLAFUR) or raltitrexed, oxaliplatin, and radiotherapy (TOMOX-RT). For PLAFUR, cisplatin (60 mg/m(2)) was given on Days 1 and 29, with a prolonged infusion of 5-fluorouracil (1,000 mg/m(2)) on Days 1-4 and 29-32, plus concurrent radiotherapy (50.4 Gy in 1.8-Gy fractions daily). For TOMOX-RT, raltitrexed (3 mg/m(2)) and oxaliplatin (130 mg/m(2)) was given on Days 1, 19, and 38 with the same radiotherapy regimen as used for PLAFUR. Surgery was performed 6-8 weeks after completion of chemoradiotherapy. All pathologic specimens were reviewed by a designated expert pathologist. The primary endpoint of this study was pathologic tumor downstaging (defined as tumor regression grade 1-2). Secondary endpoints included the incidence of ypT0, clinical tumor downstaging, sphincter-saving surgery, and acute treatment-related toxicity. RESULTS: Between 2002 and 2005, 164 patients were accrued in 10 Italian centers, 83 patients in the PLAFUR arm and 81 in the TOMOX-RT arm. Overall, tumor regression grade 1-2 was observed in 76 patients (46.4%) and ypT0 in 49 (29.9%). The tumor regression grade 1-2 rate was 41.0% vs. 51.9% (p = 0.162) and the ypT0 rate was 24.1% vs. 35.8% (p = 0.102) for the PLAFUR vs. TOMOX-RT arm, respectively. The overall rate of tumor regression grade 1 and ypN+ was 4.6%. The occurrence of ypT downstaging was significantly greater in the TOMOX-RT arm (p = 0.035). Grade 3-4 acute toxicity occurred in 19 patients (11.6%): 7.1% in the PLAFUR arm vs. 16.4% in the TOMOX-RT arm. Sphincter-saving surgery was performed in 143 patients (87.2%) overall: 87.9% in the PLAFUR arm and 86.4% in the TOMOX-RT arm. CONCLUSIONS: Compared with the PLAFUR regimen, TOMOX-RT achieved a greater incidence of downstaging but was associated with a correspondingly greater rate of acute Grade 3+ toxicity. With longer follow-up, the local control and survival rates might offer additional guidance as to the choice of regimen.

Dynamic conformal arc therapy: transmitted signal in vivo dosimetry.

A method for the determination of the in vivo isocenter dose, D(iso), has been applied to the dynamic conformal are therapy (DCAT) for thoracic tumors. The method makes use of the transmitted signal, S(t,alpha), measured at different gantry angles, a, by a small ion chamber positioned on the electronic portal imaging device. The in vivo method is implemented by a set of correlation functions obtained by the ratios between the transmitted signal and the midplane dose in a solid phantom, irradiated by static fields. The in vivo dosimetry at the isocenter for the DCAT requires the convolution between the signals, S(t,alpha), and the dose reconstruction factors, C(alpha), that depend on the patient's anatomy and on its tissue inhomogeneities along the beam central axis in the a direction. The C(alpha) factors are obtained by processing the patient's computed tomography scan. The method was tested by taking measurements in a cylindrical phantom and in a Rando Alderson phantom. The results show that the difference between the convolution calculations and the phantom measurements is within +/-2%. The in vivo dosimetry of the stereotactic DCAT for six lung tumors, irradiated with three or four arcs, is reported. The isocenter dose up to 17 Gy per therapy fraction was delivered on alternating days for three fractions. The agreement obtained in this pilot study between the total in vivo dose D(iso) and the planned dose D(iso,TPS) at the isocenter is +/-4%. The method has been applied on the DCAT obtaining a more extensive monitoring of possible systematic errors, the effect of which can invalidate the current therapy which uses a few high-dose fractions.

Implementation of a voluntary deep inspiration breath hold technique (vDIBH) using BrainLab ExacTrac infrared optical tracking system.

BACKGROUND: Voluntary deep inspiration breath hold technique (vDIBH) is considered as the key to achieving the widest cardiac sparing in whole breast irradiation. Several techniques have been implemented to achieve a reproducible, fast and friendly treatment. The aim of the present study is to implement vDIBH using the ExacTrac (BrainLAB AG, Germany) monitoring system. METHODS: Women with left-sided breast cancer, younger than 50 years or with cardiac disease, underwent whole breast RT with vDIBH using the ExacTrac (BrainLAB AG, Germany) monitoring system. Simulations were performed with patients positioned supine on a breast board with both arms raised above the head. Five optical markers were placed on the skin around the border of the left breast gland and their position was referenced with ink marking. Each patient received a training session to find the individual deep inspiration level. Finally, a vDIBH CT was taken. All patients were also studied in free breathing (FB) in order to compare the dose distribution for PTV, heart and left anterior descending coronary artery (LAD). Pre-treatment verification was carried out through the ExacTrac (BrainLAB AG, Germany) system and verified with electronic portal imaging (EPI). Moreover, daily real time EPIs in during modality (captured during the beam delivery) were taken in order to check the reproducibility. RESULTS: 34 patients have been evaluated and 30 were eligible for vDIBH. Most patients showed small setup errors during the treatment course of below 5 mm in 94.9% of the recorded fields. Mean Displacement was less in cranio-caudal direction. Mean intra-fraction displacement was below 3 mm in all directions. vDIBH plans provided better cardiac dosimetry. CONCLUSIONS: vDIBH technique using ExacTrac (BrainLAB AG, Germany) monitoring system was applied with good reproducibility.