Ultrasound-guided and 'blind' sciatic nerve injection techniques: Comparison in rat cadavers.

OBJECTIVE: To compare the success rate and extent of sciatic nerve staining with a bupivacaine-dye solution using two injection techniques: 'blind' or ultrasound-guided approach. STUDY DESIGN: Prospective, experimental, randomized, cadaveric study. ANIMALS: Adult female Wistar rat cadavers [n = 24, mass 352 g (323-374)]. METHODS: Each sciatic nerve was randomly allocated to one of two groups: 'blind' (group B) or ultrasound-guided approach (group US) to injection. Following injection of bupivacaine-dye solution (0.1 mL), gross anatomical dissection was performed to visualize nerve staining, categorizing it as either positive or negative. The length of nerve staining was then measured and visual inspection conducted to identify potential nerve damage. Fisher's exact test was used to compare positive or negative nerve staining, and the Wilcoxon signed rank test used to compare the length of nerve staining between groups. RESULTS: In group B, the bupivacaine-dye solution stained 16/24 sciatic nerves (67% success). In group US, staining was successfully observed in all 24 nerves (100% success, p < 0.004). The length of nerve staining [median (interquartile range)] was 2 (2-3) mm in group B and 5 (4-6) mm in group US (p < 0.001). One sciatic nerve in group B had injectate distributed over 16 mm, suggestive of an intraneural injection. No signs of laceration or nerve damage were visible under 6× magnification in either group. CONCLUSIONS AND CLINICAL RELEVANCE: The ultrasound-guided approach for sciatic nerve injection demonstrated a higher success rate with superior injectate distribution when compared with the 'blind' approach. Ultrasound guidance is recommended over a 'blind' approach for sciatic nerve block in rats when possible.

Multicentric Assessment of Safety and Efficacy of Combinatorial Adjuvant Brain Metastasis Treatment by Intraoperative Radiation Therapy and Immunotherapy.

PURPOSE: After surgical resection of brain metastases (BMs), intraoperative radiation therapy (IORT) provides a promising alternative to adjuvant external beam radiation therapy by enabling superior organ-at-risk preservation, reduction of in-hospital times, and timely admission to subsequent systemic treatments, which increasingly comprise novel targeted immunotherapeutic approaches. We sought to assess the safety and efficacy of IORT in combination with immune checkpoint inhibitors (ICIs) and other targeted therapies (TTs). METHODS AND MATERIALS: In a multicentric approach incorporating individual patient data from 6 international IORT centers, all patients with BMs undergoing IORT were retrospectively assessed for combinatorial treatment with ICIs/TTs and evaluated for toxicity and cumulative rates, including wound dehiscence, radiation necrosis, leptomeningeal spread, local control, distant brain progression (DBP), and estimated overall survival. RESULTS: In total, 103 lesions with a median diameter of 34 mm receiving IORT combined with immunomodulatory systemic treatment or other TTs were included. The median follow-up was 13.2 (range, 1.2-102.4) months, and the median IORT dose was 25 (range, 18-30) Gy prescribed to the applicator surface. There was 1 grade 3 adverse event related to IORT recorded (2.2%). A 4.9% cumulative radiation necrosis rate was observed. The 1-year local control rate was 98.0%, and the 1-year DBP-free survival rate was 60.0%. Median time to DBP was 5.5 (range, 1.0-18.5) months in the subgroup of patients experiencing DBP, and the cumulative leptomeningeal spread rate was 4.9%. The median estimated overall survival was 26 (range, 1.2 to not reached) months with a 1-year survival rate of 74.0%. Early initiation of immunotherapy/TTs was associated with a nonsignificant trend toward improved DBP rate and overall survival. CONCLUSIONS: The combination of ICIs/TTs with IORT for resected BMs does not seem to increase toxicity and yields encouraging local control outcomes in the difficult-to-treat subgroup of larger BMs. Time gaps between surgery and systemic treatment could be shortened or avoided. The definitive role of IORT in local control after BM resection will be defined in a prospective trial.

Evaluation of the technique of localization of the epidural space with the aid of a peripheral nerve stimulator and epidurographic, comparing two techniques for determining the infused volume, in rabbits (Oryctolagus Cuniculus).

Veterinary care for rabbits has been growing, and, consequently, the anesthetic and analgesic management of this species must be improved. The aim of the present study was to evaluate the technique of localization of the epidural space with the aid of a peripheral nerve stimulator and epidurographic, comparing two techniques for determining the infused volume in rabbits (Oryctolagus Cuniculus). In a prospective, randomized blinded study, six healthy New Zealand rabbits, adults, and weighing from 2.2 kg to 3.8 kg received two treatments, at 1 week intervals: 0.33 mL/kg (treatment I) or 0.05 mL per centimeter of the spine (treatment II) of ioexol epidurally. In both treatments, a peripheral nerve stimulator (2 Hz, 0.25 mA and 0.1 milliseconds) was used to determine the location of the epidural space. Latero-lateral and ventro-dorsal radiographs were taken after five (T5) and twenty-five minutes (T25) of iohexol administration. The epidural space was correctly accessed in 92% of attempts. Treatment I received a smaller volume of contrast than treatment II, 1.0 ± 0.2 mL versus 2.1 ± 0.1 mL (mean ± standard deviation), respectively (p = 0.007). At T5, the cranial progression of the contrast varied between L4 and L5 in treatment I, and L5 and T10 in treatment II. At T25, no contrast was observed in any rabbit. In conclusion, peripheral nerve stimulator aided in accessing the lumbosacral epidural space, and the administration of 0.05 mL per centimeter of the spine resulted in greater cranial progression of contrast.

Ultrasound-guided sciatic nerve block in Wistar rat cadavers: Relevant anatomy and injection distribution.

OBJECTIVE: To investigate the feasibility of an ultrasound-guided sciatic nerve block by describing the sonoanatomy and comparing the distribution of two volumes of bupivacaine dye solution for nerve staining. STUDY DESIGN: Randomized, experimental, assessor-blinded cadaveric study. ANIMALS: A total of 40 adult female Wistar rat cadavers. METHODS: After studying the sonoanatomy of the sciatic nerve and adjacent structures using a high-resolution linear transducer (19-5 MHz), rat cadavers were randomly divided into two groups that were administered either 0.1 mL (group 0.1) or 0.2 mL (group 0.2) of bupivacaine dye solution per nerve, delivered via an in-plane technique. The extent of nerve staining was subsequently evaluated following dissection. Statistical analysis consisted of assessing data distribution using the Shapiro-Wilk test, followed by paired t-tests for continuous data, Mann-Whitney U test and McNemar's test for categorical data. Statistical significance was defined as p < 0.05. RESULTS: The sciatic nerve was identified bilaterally as a double ellipsoid-shaped image, surrounded by a hyperechoic fascia separating the biceps femoris from the adductor muscle. The hypoechoic structure formed by the bupivacaine dye solution around the nerve was effectively visualized using ultrasound imaging. Sciatic nerve staining was successfully achieved in all pelvic limbs, with dye spread of 4.82 ± 1.55 mm and 5.47 ± 2.18 mm in groups 0.1 and 0.2, respectively (p = 0.128). CONCLUSIONS AND CLINICAL RELEVANCE: This study achieved a detailed understanding of the sonoanatomy of the sciatic nerve and its adjacent structures, highlighting the feasibility of the ultrasound-guided technique for injection in Wistar rats. Furthermore, the results show a comparable distribution of dye solution in both groups. Use of the ultrasound-guided sciatic nerve block technique in rats not only exhibits substantial potential for regional anesthesia but also opens avenues for translational studies.

Involved-Field Radiation Therapy for Patients With Unresectable Pancreatic Adenocarcinomas: Failure Pattern Analysis.

Introduction Unresectable pancreatic tumors are frequently diagnosed. Initial treatment is carried out with chemotherapy. Eventually, in selected cases, radiotherapy may be used to improve local control rates and relieve the symptoms. The volume of radiotherapy treatment fields is the subject of controversy in the literature. The use of involved fields with the gross tumor volume encompassing the primary tumor and lymph nodes considered clinically positive is associated with a lower rate of side effects, but can lead to a higher rate of regional loco failures, especially in regional lymph nodes. The purpose of this article is to analyze the failure pattern of chemotherapy and involved-field radiation therapy (IFRT) for treating patients with unresectable pancreatic adenocarcinomas. Methods Clinical records of thirty consecutive patients treated from March 2016 to June 2020 for unresectable pancreatic adenocarcinoma were analyzed. The patients were treated with initial systemic chemotherapy (median: 6 cycles) with regimens based on gemcitabine or oxaliplatin-irinotecan (folfirinox/folfox) followed by radiotherapy (total dose of 50-54 Gy/with fractionation of 2 Gy/day). The patients were treated with IFRT. Local failure (LF) was defined as an increase in radiographic abnormality within the planning target volume (PTV). Elective nodal failure (ENF) was defined as recurrence in any lymph node region outside the PTV. Any other failure was defined as distant failure (DF). Results The median age of the patients was 68 years (range: 44-80 years); 20 patients (66.7%) were men, and 11 (36.6%) and 19 (63.4%) patients presented with tumors of stage II and III, respectively. Most patients (63.3%) had tumors in the pancreatic head. The median survival was 17.2 months. Tumor recurrences were classified as LF, DF, LF and DF in 7 (23.3%), 17 (56.7%), and 5 (16.7%) patients, respectively. Only one patient (3.3%) had both LF and ENF. No severe side effects related to radiotherapy were reported. Conclusion The use of IFRT did not cause a significant amount of ENF, besides presenting low morbidity, which is of special importance for patients with locally advanced tumors or low performance status. The predominant failure pattern was distant metastases.

Moderately hypofractionated post-operative radiation therapy for breast cancer: preferences amongst radiation oncologists from countries in Latin America and the Caribbean.

Background: The safety and effectiveness of moderately hypofractionated post-operative radiation therapy for breast cancer were demonstrated by several trials. This study aimed to evaluate the current patterns of practice and prescription preference about moderately hypofractionated post-operative radiation therapy to assess possible aspects that affect the decision-making process regarding the use of fractionation in breast cancer patients in Latin America and the Caribbean (LAC). We also aimed to identify factors that can restrain the utilization of moderately hypofractionated post-operative radiation therapy for breast cancer. Materials an methods: Radiation oncologists from LAC were invited to contribute to this study. A 38-question survey was used to evaluate their opinions. Results: A total of 173 radiation oncologists from 13 countries answered the questionnaire. The majority of respondents (84.9%) preferred moderately hypofractionated post-operative radiation therapy as their first choice in cases of whole breast irradiation. Whole breast plus regional nodal irradiation, post-mastectomy (chest wall and regional nodal irradiation) without reconstruction, and post-mastectomy (chest wall and regional node irradiation) with reconstruction hypofractionated post-operative radiation therapy was preferred by 72.2% 71.1%, and 53.7% of respondents, respectively. Breast cancer stage, and flap-based breast reconstruction were the factors associated with absolute contraindications for the use of hypofractionated schedules. Conclusion: Even though moderately hypofractionated post-operative radiation therapy for breast cancer is considered a new standard to the vast majority of the patients, its unrestricted application in clinical practice across LAC still faces reluctance.

Risk of metastasis in BRCA2 carriers diagnosed with triple-negative breast cancer.

BACKGROUND: Triple-negative breast cancer (TNBC) is the neoplasia most associated with BRCA1 germline pathogenic variants (PV) and is more likely to develop metastases than the other breast cancer (BC) subtypes, mainly in the lungs and the central nervous system (CNS). Recently, BRCA2 carriers were shown to have a higher risk for developing CNS metastases. However, the patterns of recurrence and metastases of BRCA2 carriers with TNBC are unknown. METHODS: TNBC patient data attending the A.C. Camargo Cancer Center, from 1998 through 2020, were verified either by medical records or by BRCA1/2 genetic testing carried out. Multivariable logistic regression models were fit to the data to assess the independent factors for bone and CNS metastases. Adjustment was done using all independent variables with p < 0.2 in the univariable Cox model to describe the relationship between the independent variables until time of death. RESULTS: A total of 388 TNBC patients were evaluated. We identified PV in BRCA1/2 genes in 21% (82/388), being 17.7% (69/388) in BRCA1 and only 3.3% (13/388) in BRCA2. A total of 120 patients (31%) developed distant metastases. Bone or CNS metastases were observed in 40% and 60% of BRCA2 PV carriers (p = 0.155), respectively. The BRCA2 carriers tended to have a higher likelihood of developing bone metastases (OR, 4.06; 95% CI, 0.82-20.01; p = 0.085), when compared to BRCA1 carriers (OR, 0.6; 95% CI, 0.12-2.87; p = 0.528). BRCA2 carriers had an OR of 1.75 (95% CI, 0.33-9.14; p = 0.503) for CNS metastasis development, while BRCA1 carriers had an OR of 0.72 (95% CI, 0.23-2.23; p = 0.574). CONCLUSIONS: Patients with TNBC and PV in the BRCA2 gene had higher frequencies of secondary bone involvement and CNS in the course of the disease. However, the BRCA2 PV did not represent an independent outcome predictor of metastases and overall survival. Efforts to increase the number of BRCA2 carriers among TNBC patients are crucial for determining their risk of developing bone and CNS metastases compared to BRCA2 noncarriers.

Intraoperative radiotherapy for brain metastases: first-stage results of a single-arm, open-label, phase 2 trial.

OBJECTIVE: Focal stereotactic radiosurgery to the surgical cavity lowers local recurrence after resection of brain metastases (BM). To evaluate local control (LC) and brain disease control (BDC) after intraoperative radiotherapy (IORT) for resected BM. METHODS: Adult patients with completely resected single supratentorial BM were recruited and underwent IORT to the cavity with a prescribed dose of 18 Gy to 1 mm-depth. Primary endpoints were actuarial LC and BDC. Local failure (LF) and distant brain failure (DBF), with death as a competing risk, were estimated. Secondary endpoints were overall survival (OS) and incidence of radiation necrosis (RN). Simon's two-stage design was used and estimated an accrual of 10 patients for the first-stage analysis and a LC higher than 63% to proceed to second stage. We report the final analysis of the first stage. RESULTS: Between June 2019 to November 2020, 10 patients were accrued. Median clinical and imaging FU was 11.2 and 9.7 months, respectively. Median LC was not reached and median BDC was 5 months. The 6-month and 12-month LC was 87.5%. The 6-month and 12-month BDC was 39% and 13%, respectively. Incidence of LF at 6 and 12 months was 10% and of DBF at 6 and 12 months was 50% and 70%, respectively. Median OS was not reached. The 6-month and 12-month OS was 80%. One patient had asymptomatic RN. CONCLUSION: IORT for completely resected BM is associated with a potential high local control and low risk of RN, reaching the pre-specified criteria to proceed to second stage and warranting further studies.

Postmastectomy Radiation Therapy Bolus Associated Complications in Patients Who Underwent 2-stage Breast Reconstruction.

Purpose: This study aimed to evaluate the association of bolus and 2-stage breast reconstruction complications, and whether the dosimetric advantage translates into improvements in local control. Methods and Materials: We retrospectively analyzed data from 2008 to 2019 of women who underwent a mastectomy and a planned 2-stage breast reconstruction, followed by adjuvant radiation therapy. We reviewed all data from medical records and radiation plans regarding patient characteristics, diagnoses, surgeries, complications, pathology, staging, systemic therapy, radiation therapy, and outcomes, and compared complication rates according to bolus usage. Results: A total of 288 women, age 25 to 71 years, were included in the study. Of these women, 6 were treated with daily bolus and 19 with alternate days bolus, totaling 25 of 288 patients (8.7%) in the bolus group. A total of 226 patients (78.5%) had the second stage performed. The median follow-up time was 61 months. The rates for 5-year overall survival and locoregional control were both 97%, and the metastasis-free rate was 83%. In the first stage, 6.25% of patients in the entire cohort had an infection and 4.2% had implant loss. Daily bolus significantly increased the risk of expander infection (hazard ratio [HR]: 10.3; 95% confidence interval [CI], 1.7-61.8) and loss (HR: 13.89; 95% CI, 2.24-85.98), but alternate-day bolus showed a nonsignificant increase for expander infection (HR: 1.14; 95% CI, 0.14-9.295) and loss (HR: 1.5; 95% CI, 0.19-12.87). Bolus was not associated with second-stage complications or local-regional failure. Local infection and implant loss were more frequent in the second than in the first stage (5.2% vs 10.2% and 4.2% vs 12.8%, respectively). Conclusions: Skin bolus significantly increased first-stage breast reconstruction complications (infection and reconstruction failure). Despite the small sample size and the need for future studies, these findings need to be taken into consideration when planning treatment and reconstruction, and recommendations should be individualized.

Impact of cranial stereotactic radiotherapy associated with immunotherapy with nivolumab and ipilimumab on overall survival in patients with melanoma brain metastases: a real-world evidence

PurposeTo evaluate the impact of cranial stereotactic radiotherapy (SRT) on overall survival (OS) of melanoma brain metastases (MBM) patients treated with combined nivolumab and ipilimumab (CNI) in a contemporary and real-world setting.Methods/patientsThe study was performed by using TriNetX, a global health network dataset of electronic medical records from patients in 49 healthcare organizations. We queried for patients with specific terms between January 2016 and December 2020 and run a propensity score matching (PSM) analysis. OS was estimated by Kaplan–Meier and log-rank test was applied.ResultsAfter initial query and PSM, 114 patients were selected in each cohort. Median OS was 327 days in CNI and not reached in the CNI + SRT cohort, with OS probability of 54.4 and 40.9%, respectively (log-rank P = .0057). CNI + SRT was associated with significantly decreased mortality (HR, 0.57; 95% CI 0.377-0.853; proportionality P = .0034).ConclusionsThis real-world analysis showed that CNI + SRT led to an improvement in OS compared to CNI. (AU)

Salvage Post-Operative Stereotatic Ablative Radiotherapy for Re-Current Squamous Cell Carcinoma of Head and Neck.

Background and Objectives: Patients with recurrent squamous cell carcinoma of the head and neck (rHNC) face an aggressive disease. Surgical resection is the gold standard treatment. Immediate adjuvant post-operative stereotactic ablative radiotherapy (PO-SABR) for rHNC is debatable. Materials and Methods: We retrospectively identified patients who were treated with PO-SABR at the AC Camargo Cancer Center, Brazil. Results: Eleven patients were treated between 2018 and 2021. The median time between salvage surgery and PO-SABR was 31 days (range, 25-42) and the median PO-SABR total dose was 40 Gy (range, 30-48 Gy). The 2-and 4-year actuarial DFS were 62.3% and 41.6%, while the 2-and 4-year OS probabilities were 80.0% and 53.3%, respectively. Eight (72.7%) patients were alive and six (54.5%) were without disease at the last follow-up. Two (18.1%) patients had local failure in the PO-SABR field. Three (27.3%) patients had distant metastasis, diagnosed in a median time of 9 months (range, 4-13) after completion of PO-SABR. On univariate analysis, predictive factors related to worse OS were: interval between previous radiotherapy and PO-SABR ≤ 24 months (p = 0.033) and location of the salvage target in the oral cavity (p = 0.013). The total dose of PO-SABR given in more than three fractions was marginally statistically significant, favoring the OS (p = 0.051). Conclusions: Our results encourage the use of a more aggressive approach in selected patients with rHNC by combining salvage surgery with immediate PO-SABRT, but this association needs to be further explored.

Heterogeneity of HER2 Expression in Circulating Tumor Cells of Patients with Breast Cancer Brain Metastases and Impact on Brain Disease Control.

HER2 expression switching in circulating tumor cells (CTC) in breast cancer is dynamic and may have prognostic and predictive clinical implications. In this study, we evaluated the association between the expression of HER2 in the CTC of patients with breast cancer brain metastases (BCBM) and brain disease control. An exploratory analysis of a prospective assessment of CTC before (CTC1) and after (CTC2) stereotactic radiotherapy/radiosurgery (SRT) for BCBM in 39 women was performed. Distant brain failure-free survival (DBFFS), the primary endpoint, and overall survival (OS) were estimated. After a median follow-up of 16.6 months, there were 15 patients with distant brain failure and 16 deaths. The median DBFFS and OS were 15.3 and 19.5 months, respectively. The median DBFFS was 10 months in patients without HER2 expressed in CTC and was not reached in patients with HER2 in CTC (p = 0.012). The median OS was 17 months in patients without HER2 in CTC and was not reached in patients with HER2 in CTC (p = 0.104). On the multivariate analysis, DBFFS was superior in patients who were primary immunophenotype (PIP) HER2-positive (HR 0.128, 95% CI 0.025-0.534; p = 0.013). The expression of HER2 in CTC was associated with a longer DBFFS, and the switching of HER2 expression between the PIP and CTC may have an impact on prognosis and treatment selection for BCBM.

Impact of cranial stereotactic radiotherapy associated with immunotherapy with nivolumab and ipilimumab on overall survival in patients with melanoma brain metastases: a real-world evidence.

PURPOSE: To evaluate the impact of cranial stereotactic radiotherapy (SRT) on overall survival (OS) of melanoma brain metastases (MBM) patients treated with combined nivolumab and ipilimumab (CNI) in a contemporary and real-world setting. METHODS/PATIENTS: The study was performed by using TriNetX, a global health network dataset of electronic medical records from patients in 49 healthcare organizations. We queried for patients with specific terms between January 2016 and December 2020 and run a propensity score matching (PSM) analysis. OS was estimated by Kaplan-Meier and log-rank test was applied. RESULTS: After initial query and PSM, 114 patients were selected in each cohort. Median OS was 327 days in CNI and not reached in the CNI + SRT cohort, with OS probability of 54.4 and 40.9%, respectively (log-rank P = .0057). CNI + SRT was associated with significantly decreased mortality (HR, 0.57; 95% CI 0.377-0.853; proportionality P = .0034). CONCLUSIONS: This real-world analysis showed that CNI + SRT led to an improvement in OS compared to CNI.

Simulation of Organic Liquid Product Deoxygenation through Multistage Countercurrent Absorber/Stripping Using CO2 as Solvent with Aspen-HYSYS: Process Modeling and Simulation.

In this work, the deoxygenation of organic liquid products (OLP) obtained through the thermal catalytic cracking of palm oil at 450 °C, 1.0 atmosphere, with 10% (wt.) Na2CO3 as a catalyst, in multistage countercurrent absorber columns using supercritical carbon dioxide (SC-CO2) as a solvent, with an Aspen-HYSYS process simulator, was systematically investigated. In a previous study, the thermodynamic data basis and EOS modeling necessary to simulate the deoxygenation of OLP was presented. This work addresses a new flowsheet, consisting of 03 absorber columns, 10 expansions valves, 10 flash drums, 08 heat exchanges, 01 pressure pump, and 02 make-ups of CO2, aiming to improve the deacidification of OLP. The simulation was performed at 333 K, 140 bar, and (S/F) = 17; 350 K, 140 bar, and (S/F) = 38; 333 K, 140 bar, and (S/F) = 25. The simulation shows that 81.49% of OLP could be recovered and that the concentrations of hydrocarbons in the extracts of absorber-01 and absorber-02 were 96.95 and 92.78% (wt.) on a solvent-free basis, while the bottom stream of absorber-03 was enriched in oxygenated compounds with concentrations of up to 32.66% (wt.) on a solvent-free basis, showing that the organic liquid products (OLP) were deacidified and SC-CO2 was able to deacidify the OLP and obtain fractions with lower olefin contents. The best deacidifying condition was obtained at 333 K, 140 bar, and (S/F) = 17.

Circulating tumor cell methylation profiles reveal the classification and evolution of non-small cell lung cancer.

Background: The ability of circulating tumor cells (CTCs) to identify lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) could improve pathological diagnosis and the selection of treatments for non-small cell lung cancer (NSCLC). Previous studies have shown that deoxyribonucleic acid (DNA) methylation exhibits cell and tissue specificity. Thus, we aimed to explore the methylation status of CTCs in LUAD and LUSC and identify the potential biomarkers. Methods: We first analyzed Infinium 450K methylation profiles obtained from The Cancer Genome Atlas and Gene Expression Omnibus. We then performed whole-genome sequencing of CTCs in tumor and matched normal lung tissues and white blood cells from 6 NSCLC patients. Results: The bioinformatics analysis revealed a NSCLC-specific DNA methylation marker panel, which could accurately distinguish between LUAD and LUSC with high diagnostic accuracy. The whole-genome sequencing of CTCs in NSCLC patients also showed 100% accuracy for distinguishing between LUAD and LUSC based on the CTC methylation profiles. To investigate the function of CTCs, we further analyzed similar and different methylation profiles between the CTCs and their primary tumors, and found very high similarities between the CTCs and their primary tumor tissues, indicating that these cells inherit information from primary tumors. However, the CTCs also displayed some characteristics that differed to those of primary tumor tissues, which suggest that CTCs acquire some unique characteristics after migrating from the primary tumor; these characteristics may partly explain the ability of tumor cells to evade immune surveillance. Conclusions: Our findings provide insights into the potential use of CTCs in the pathological classification of NSCLC patients. Our findings also show how CTC primary tumor inheritance and CTC evolution affect metastasis and immune escape.

Multiline aiming at phenotypic stability and rice blast resistance

This study aimed to verify the efficiency of multilines in reducing blast progress and their potential benefits to phenotypic stability in rice. The experiments were conducted in the 2016/17 and 2017/18 agricultural years. A randomized block design was performed with three replications, evaluating 12 lines and a multiline, which consisted of five lines from the Cultivation and Use Value (CUV) test. The multiline presented an estimated grain yield above the average of experiments of around seven bags ha-1 and superior performance in early flowering, justifying the high phenotypic stability for these characters. In this case, the line selection for composing the multiline was favorable and efficient, highlighted by a higher agronomic performance than most lines of the CUV test. The multiline is an adequate strategy to provide higher phenotypic stability and reduce blast progress in the field.

Clinical Prognostic Factors for Patients With Esophageal Cancer Treated With Definitive Chemoradiotherapy.

Background Treatment with definitive chemoradiotherapy (CRT) is the best option for patients with locally advanced esophageal tumors considered unresectable or for patients without clinical conditions to undergo surgical treatment. Technological advances in radiotherapy in the last decades have made treatment more accurate with less toxicity, and the association with more effective systemic treatment has been gradually improving survival rates. Aim Evaluate clinical prognostic factors for progression-free survival (PFS) and overall survival (OS) in patients with esophageal cancer treated with definitive radiotherapy (RT) and chemotherapy (ChT). Material and methods The clinical records of 60 patients treated from April 2011 until December 2019 with esophageal cancer considered unresectable and/or without clinical conditions for surgery, treated with definitive CRT, were analyzed. All patients had upper digestive endoscopy (UDE) with positive biopsy, neck, chest, and abdominal CT scan, and 18F-fluorodeoxyglucose positron-emission tomography (PET-CT). Patients were followed with physical examination and CTs every three months in the first and second years and every six months from the third year of follow-up. UDE was made every three to six months after the end of the treatment or in suspicion of tumor recurrence. PET-CT was also performed in the follow-up when clinically necessary. Local and regional failure (LRF) was defined as abnormalities in the image tests within the planning target volume (PTV) and/or positive biopsy on UDE. Any other failure was defined as a distant failure (DF). PFS was defined in the record of the first tumor recurrence site and OS in the death record from the date of the start of treatment. Results The median age of the patients was 66 years (range: 33 to 83 years) and 46 patients (76.7%) were male. Squamous cell carcinoma (SCC) was the most frequent histological type (85%). Most patients had tumors located in the mid-thoracic esophagus (53.3%) and stage III or IV (59.9%). All patients were treated using 3D (76.7%) or intensity-modulated radiotherapy (IMRT; 23.3%). The median total dose was 50.4Gy (41.4-50.4). All patients received platinum-based ChT concomitant with RT. The most common regimen used was carboplatin and paclitaxel, with a median of five cycles. With a median follow-up of 19 months, the median PFS and OS were 10 and 20 months, respectively. LRF and DF as the first site of failure were observed in 22 (36.6%) and 26 (43.3%) patients, respectively. In the univariate analysis, tumor length lower than 2.6 cm, gross tumor volume (GTV) volume lower than 28 cm3, clinical tumor stages T1 and T2, clinical node stage N0, clinical prognostic stage groups I and II, and complete response to treatment, were statistically significant factors for better PFS and OS. In the multivariate analysis, the presence of clinical nodal stage N0 was related to better PFS (p=0.02). Conclusion Node clinical status was the most important clinical factor for PFS. Despite all the technical progress observed in radiotherapy, treatments concomitant with platinum-based chemotherapy are associated with high levels of LRF and DF. New strategies in systemic therapy and radiotherapy are necessary for improving outcomes.

Radiation therapy with elective lymph node irradiation for breast cancer: dosimetric study and impact on cardiovascular risk and second neoplasms.

OBJECTIVE: The aim of this study was to perform dosimetric analysis of radiotherapy (RT) plans with or without elective nodal irradiation (ENI) and estimate whether the increase in mean doses (MDs) in the heart and lungs with ENI may lead to late side effects that may surpass the benefits of treatment. METHODS: The dosimetric analysis of 30 treatment plans was done with or without ENI. The planning and dose-volume histograms were analyzed, and the impact on the mortality of cardiovascular and lung cancer was estimated based on the correlation of the dosimetric data with data from population studies. RESULTS: RT with ENI increased the doses in the lungs and heterogeneity in the plans compared to breast-exclusive RT. When the increase in MDs is correlated with the increase of late side-effect risks, the most important effect of ENI is the increased risk of lung cancer, especially in patients who smoke (average increase in absolute risk=1.38%). The increase in the absolute risk of cardiovascular diseases was below 0.1% in the all the situations analyzed. CONCLUSIONS: ENI increases the heterogeneity and the doses at the lungs. When recommending ENI, the risks and benefits must be taken into account, considering the oncology factors and the plan of each patient. Special attention must be given to patients who smoke as ENI may lead to a significant increase in MD in the lung and the increased risk of radiation-induced lung cancer may surpass the benefits from this treatment.

Radiation therapy with elective lymph node irradiation for breast cancer: dosimetric study and impact on cardiovascular risk and second neoplasms

SUMMARY OBJECTIVE: The aim of this study was to perform dosimetric analysis of radiotherapy (RT) plans with or without elective nodal irradiation (ENI) and estimate whether the increase in mean doses (MDs) in the heart and lungs with ENI may lead to late side effects that may surpass the benefits of treatment. METHODS: The dosimetric analysis of 30 treatment plans was done with or without ENI. The planning and dose-volume histograms were analyzed, and the impact on the mortality of cardiovascular and lung cancer was estimated based on the correlation of the dosimetric data with data from population studies. RESULTS: RT with ENI increased the doses in the lungs and heterogeneity in the plans compared to breast-exclusive RT. When the increase in MDs is correlated with the increase of late side-effect risks, the most important effect of ENI is the increased risk of lung cancer, especially in patients who smoke (average increase in absolute risk=1.38%). The increase in the absolute risk of cardiovascular diseases was below 0.1% in the all the situations analyzed. CONCLUSIONS: ENI increases the heterogeneity and the doses at the lungs. When recommending ENI, the risks and benefits must be taken into account, considering the oncology factors and the plan of each patient. Special attention must be given to patients who smoke as ENI may lead to a significant increase in MD in the lung and the increased risk of radiation-induced lung cancer may surpass the benefits from this treatment.