Novel Measurement of the Neutron Magnetic Form Factor from A=3 Mirror Nuclei

The electromagnetic form factors of the proton and neutron encode information on the spatial structure of their charge and magnetization distributions. While measurements of the proton are relatively straightforward, the lack of a free neutron target makes measurements of the neutron's electromagnetic structure more challenging and more sensitive to experimental or model-dependent uncertainties. Various experiments have attempted to extract the neutron form factors from scattering from the neutron in deuterium, with different techniques providing different, and sometimes large, systematic uncertainties. We present results from a novel measurement of the neutron magnetic form factor using quasielastic scattering from the mirror nuclei ^{3}H and ^{3}He, where the nuclear effects are larger than for deuterium but expected to largely cancel in the cross-section ratios. We extracted values of the neutron magnetic form factor for low-to-modest momentum transfer, 0.6 Collapse

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Affiliation(s)

S N Santiesteban University of New Hampshire, Durham, New Hampshire 03824, USA
S Li University of New Hampshire, Durham, New Hampshire 03824, USA Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
D Abrams University of Virginia, Charlottesville, Virginia 22904, USA
S Alsalmi Kent State University, Kent, Ohio 44240, USA King Saud University, Riyadh 11451, Kingdom of Saudi Arabia
D Androic University of Zagreb, Zagreb, Croatia
K Aniol California State University, Los Angeles, California 90032, USA
J Arrington Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA Argonne National Laboratory, Lemont, Illinois 60439, USA
T Averett William and Mary, Williamsburg, Virginia 23185, USA
C Ayerbe Gayoso William and Mary, Williamsburg, Virginia 23185, USA
J Bane University of Tennessee, Knoxville, Tennessee 37966, USA
S Barcus William and Mary, Williamsburg, Virginia 23185, USA
J Barrow University of Tennessee, Knoxville, Tennessee 37966, USA Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
A Beck Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
V Bellini INFN Sezione di Catania, Italy
H Bhatt Mississippi State University, Mississippi State, Mississippi 39762, USA
D Bhetuwal Mississippi State University, Mississippi State, Mississippi 39762, USA
D Biswas Hampton University, Hampton, Virginia 23669, USA
A Camsonne Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
J Castellanos Florida International University, Miami, Florida 33199, USA
J Chen William and Mary, Williamsburg, Virginia 23185, USA
J-P Chen Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
D Chrisman Michigan State University, East Lansing, Michigan 48824, USA
M E Christy Hampton University, Hampton, Virginia 23669, USA Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
C Clarke Stony Brook, State University of New York, New York 11794, USA
S Covrig Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
R Cruz-Torres Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
D Day University of Virginia, Charlottesville, Virginia 22904, USA
D Dutta Mississippi State University, Mississippi State, Mississippi 39762, USA
E Fuchey University of Connecticut, Storrs, Connecticut 06269, USA
C Gal University of Virginia, Charlottesville, Virginia 22904, USA
F Garibaldi INFN, Rome, Italy
T N Gautam Hampton University, Hampton, Virginia 23669, USA
T Gogami Tohoku University, Sendai, Japan
J Gomez Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
P Guèye Hampton University, Hampton, Virginia 23669, USA Michigan State University, East Lansing, Michigan 48824, USA
T J Hague Kent State University, Kent, Ohio 44240, USA
J O Hansen Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
F Hauenstein Old Dominion University, Norfolk, Virginia 23529, USA
W Henry Temple University, Philadelphia, Pennsylvania 19122, USA
D W Higinbotham Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
R J Holt Argonne National Laboratory, Lemont, Illinois 60439, USA
C Hyde Old Dominion University, Norfolk, Virginia 23529, USA
K Itabashi Tohoku University, Sendai, Japan
M Kaneta Tohoku University, Sendai, Japan
A Karki Mississippi State University, Mississippi State, Mississippi 39762, USA
A T Katramatou Kent State University, Kent, Ohio 44240, USA
C E Keppel Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
P M King Ohio University, Athens, Ohio 45701, USA
L Kurbany University of New Hampshire, Durham, New Hampshire 03824, USA
T Kutz Stony Brook, State University of New York, New York 11794, USA
N Lashley-Colthirst Hampton University, Hampton, Virginia 23669, USA
W B Li William and Mary, Williamsburg, Virginia 23185, USA
H Liu Columbia University, New York, New York 10027, USA
N Liyanage University of Virginia, Charlottesville, Virginia 22904, USA
E Long University of New Hampshire, Durham, New Hampshire 03824, USA
A Lovato Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA Computational Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA INFN-TIFPA Trento Institute for Fundamental Physics and Applications, 38123 Trento, Italy
J Mammei University of Manitoba, Winnipeg, MB R3T 2N2, Canada
P Markowitz Florida International University, Miami, Florida 33199, USA
R E McClellan Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
F Meddi INFN, Rome, Italy
D Meekins Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
R Michaels Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
M Mihovilovič Jožef Stefan Institute, 1000 Ljubljana, Slovenia Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana, Slovenia Institut für Kernphysik, Johannes Gutenberg-Universität Mainz, DE-55128 Mainz, Germany
A Moyer Christopher Newport University, Newport News, Virginia 23606, USA
S Nagao Tohoku University, Sendai, Japan
D Nguyen University of Virginia, Charlottesville, Virginia 22904, USA
M Nycz Kent State University, Kent, Ohio 44240, USA
M Olson Saint Norbert College, De Pere, Wisconsin 54115, USA
L Ou Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
V Owen William and Mary, Williamsburg, Virginia 23185, USA
C Palatchi University of Virginia, Charlottesville, Virginia 22904, USA
B Pandey Hampton University, Hampton, Virginia 23669, USA
A Papadopoulou Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
S Park Stony Brook, State University of New York, New York 11794, USA
T Petkovic University of Zagreb, Zagreb, Croatia
S Premathilake University of Virginia, Charlottesville, Virginia 22904, USA
V Punjabi Norfolk State University, Norfolk, Virginia 23529, USA
R D Ransome Rutgers University, New Brunswick, New Jersey 08854, USA
P E Reimer Argonne National Laboratory, Lemont, Illinois 60439, USA
J Reinhold Florida International University, Miami, Florida 33199, USA
S Riordan Argonne National Laboratory, Lemont, Illinois 60439, USA
N Rocco Theoretical Physics Department, Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
V M Rodriguez División de Ciencias y Tecnología, Universidad Ana G. Méndez, Recinto de Cupey, San Juan 00926, Puerto Rico
A Schmidt Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
B Schmookler Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
E P Segarra Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
A Shahinyan Yerevan Physics Institute, Yerevan, Armenia
S Širca Jožef Stefan Institute, 1000 Ljubljana, Slovenia Faculty of Mathematics and Physics, University of Ljubljana, 1000 Ljubljana, Slovenia
K Slifer University of New Hampshire, Durham, New Hampshire 03824, USA
P Solvignon University of New Hampshire, Durham, New Hampshire 03824, USA
T Su Kent State University, Kent, Ohio 44240, USA
R Suleiman Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
L Tang Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
Y Tian Syracuse University, Syracuse, New York 13244, USA
W Tireman Northern Michigan University, Marquette, Michigan 49855, USA
F Tortorici INFN Sezione di Catania, Italy
Y Toyama Tohoku University, Sendai, Japan
K Uehara Tohoku University, Sendai, Japan
G M Urciuoli INFN, Rome, Italy
D Votaw Michigan State University, East Lansing, Michigan 48824, USA
J Williamson University of Glasgow, Glasgow, G12 8QQ Scotland, United Kingdom
B Wojtsekhowski Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
S Wood Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606, USA
Z H Ye Argonne National Laboratory, Lemont, Illinois 60439, USA Tsinghua University, Beijing, China
J Zhang University of Virginia, Charlottesville, Virginia 22904, USA
X Zheng University of Virginia, Charlottesville, Virginia 22904, USA

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The empty pelvis syndrome: a core data set from the PelvEx collaborative

BACKGROUND

Empty pelvis syndrome (EPS) is a significant source of morbidity following pelvic exenteration (PE), but is undefined. EPS outcome reporting and descriptors of radicality of PE are inconsistent; therefore, the best approaches for prevention are unknown. To facilitate future research into EPS, the aim of this study is to define a measurable core outcome set, core descriptor set and written definition for EPS. Consensus on strategies to mitigate EPS was also explored.

METHOD

Three-stage consensus methodology was used: longlisting with systematic review, healthcare professional event, patient engagement, and Delphi-piloting; shortlisting with two rounds of modified Delphi; and a confirmatory stage using a modified nominal group technique. This included a selection of measurement instruments, and iterative generation of a written EPS definition.

RESULTS

One hundred and three and 119 participants took part in the modified Delphi and consensus meetings, respectively. This encompassed international patient and healthcare professional representation with multidisciplinary input. Seventy statements were longlisted, seven core outcomes (bowel obstruction, enteroperineal fistula, chronic perineal sinus, infected pelvic collection, bowel obstruction, morbidity from reconstruction, re-intervention, and quality of life), and four core descriptors (magnitude of surgery, radiotherapy-induced damage, methods of reconstruction, and changes in volume of pelvic dead space) reached consensus-where applicable, measurement of these outcomes and descriptors was defined. A written definition for EPS was agreed.

CONCLUSIONS

EPS is an area of unmet research and clinical need. This study provides an agreed definition and core data set for EPS to facilitate further research.

Evaluation of robustness of optimization methods in breast intensity-modulated radiation therapy using TomoTherapy

Intensity-modulated radiation therapy (IMRT) has become a popular choice for breast cancer treatment. We aimed to evaluate and compare the robustness of each optimization method used for breast IMRT using TomoTherapy. A retrospective analysis was performed on 10 patients with left breast cancer. For each optimization method (clipping, virtual bolus, and skin flash), a corresponding 50 Gy/25 fr plan was created in the helical and direct TomoTherapy modes. The dose-volume histogram parameters were compared after shifting the patients anteriorly and posteriorly. In the helical mode, when the patient was not shifted, the median D1cc (minimum dose delivered to 1 cc of the organ volume) of the breast skin for the clipping and virtual bolus plans was 52.2 (interquartile range: 51.9-52.6) and 50.4 (50.1-50.8) Gy, respectively. After an anterior shift, D1cc of the breast skin for the clipping and virtual bolus plans was 56.0 (55.6-56.8) and 50.9 (50.5-51.3) Gy, respectively. When the direct mode was used without shifting the patient, D1cc of the breast skin for the clipping, virtual bolus, and skin flash plans was 52.6 (51.9-53.1), 53.4 (52.6-53.9), and 52.3 (51.7-53.0) Gy, respectively. After shifting anteriorly, D1cc of the breast skin for the clipping, virtual bolus, and skin flash plans was 55.6 (54.1-56.4), 52.4 (52.0-53.0), and 53.6 (52.6-54.6) Gy, respectively. The clipping method is not sufficient for breast IMRT. The virtual bolus and skin flash methods were more robust optimization methods according to our analyses.

A Case of Fever, Impaired Consciousness, and Psychosis Caused by Nitrous Oxide Abuse and Misdiagnosed as Acute Meningitis

Nitrous oxide (N2O) is readily available, and its abuse for recreational purposes has become a social problem. In Japan, where N2O is strictly prohibited for non-medical use, abuse is often overlooked due to a lack of experience in the field. N2O abuse causes various long-term symptoms, including vitamin B12 deficiency, myelopathy, myeloneuropathy, subacute combined degeneration, mood changes, and psychosis. The diagnosis of N2O abuse is difficult due to the compound's short half-life and rapid elimination through the lungs. This report describes a case of fever and impaired consciousness in a patient with a history of N2O abuse.

Respiratory motion tracking of spine stereotactic radiotherapy in prone position

PURPOSE

The CyberKnife system is a specialized device for non-coplanar irradiation; however, it possesses the geometric restriction that the beam cannot be irradiated from under the treatment couch. Prone positioning is expected to reduce the dose to normal lung tissue in spinal stereotactic body radiotherapy (SBRT) owing to the efficiency of beam arrangement; however, respiratory motion occurs. Therefore, the Xsight spine prone tracking (XSPT) system is used to reduce the effects of respiratory motion. The purpose of this study was to evaluate the motion-tracking error of the spine in the prone position.

MATERIALS AND METHODS

Data from all 25 patients who underwent spinal SBRT at our institution between April 2020 and February 2022 using CyberKnife (VSI, version 11.1.0) with the XSPT tracking system were retrospectively analyzed using log files. The tumor motion, correlation, and prediction errors for each patient were examined. Furthermore, to assess the potential relationships between the parameters, the relationships between the tumor-motion amplitudes and correlation or prediction errors were investigated using linear regression.

RESULTS

The tumor-motion amplitudes in each direction were as follows: superior-inferior (SI), 0.51 ± 0.39 mm; left-right (LR), 0.37 ± 0.29 mm; and anterior-posterior (AP), 3.43 ± 1.63 mm. The overall mean correlation and prediction errors were 0.66 ± 0.48 mm and 0.06 ± 0.07 mm, respectively. The prediction errors were strongly correlated with the tumor-motion amplitudes, whereas the correlation errors were not.

CONCLUSIONS

This study demonstrated that the correlation error of spinal SBRT in the prone position is sufficiently small to be independent of the tumor-motion amplitude. Furthermore, the prediction error is small, contributing only slightly to the tracking error. These findings will improve the understanding of how to compensate for respiratory-motion uncertainty in the prone position.

Prehospital ABC (Age, Bystander and Cardiogram) scoring system to predict neurological outcomes of cardiopulmonary arrest on arrival: post hoc analysis of a multicentre prospective observational study

BACKGROUND

There is currently limited evidence to guide prehospital identification of patients with cardiopulmonary arrest on arrival (CPAOA) to hospital who have potentially favourable neurological function. This study aimed to develop a simple scoring system that can be determined at the contact point with emergency medical services to predict neurological outcomes.

METHODS

We analysed data from patients with CPAOA using a regional Japanese database (SOS-KANTO), from January 2012 to March 2013. Patients were randomly assigned into derivation and validation cohorts. Favourable neurological outcomes were defined as cerebral performance category 1 or 2. We developed a new scoring system using logistic regression analysis with the following predictors: age, no-flow time, initial cardiac rhythm and arrest place. The model was internally validated by assessing discrimination and calibration.

RESULTS

Among 4907 patients in the derivation cohort and 4908 patients in the validation cohort, the probabilities of favourable outcome were 0.9% and 0.8%, respectively. In the derivation cohort, age ≤70 years (OR 5.11; 95% CI 2.35 to 11.14), no-flow time ≤5 min (OR 4.06; 95% CI 2.06 to 8.01) and ventricular tachycardia or fibrillation as initial cardiac rhythm (OR 6.66; 95% CI 3.45 to 12.88) were identified as predictors of favourable outcome. The ABC score consisting of Age, information from Bystander and Cardiogram was created. The areas under the receiver operating characteristic curves of this score were 0.863 in the derivation and 0.885 in the validation cohorts. Positive likelihood ratios were 6.15 and 6.39 in patients with scores >2 points and were 11.06 and 17.75 in those with 3 points.

CONCLUSION

The ABC score showed good accuracy for predicting favourable neurological outcomes in patients with CPAOA. This simple scoring system could potentially be used to select patients for extracorporeal cardiopulmonary resuscitation and minimise low-flow time.

Minimum standards of pelvic exenterative practice: PelvEx Collaborative guideline

This document outlines the important aspects of caring for patients who have been diagnosed with advanced pelvic cancer. It is primarily aimed at those who are establishing a service that adequately caters to this patient group. The relevant literature has been summarized and an attempt made to simplify the approach to management of these complex cases.

Fiducial marker position affects target volume in stereotactic lung irradiation

Purpose

Real‐time tracking systems of moving respiratory targets such as CyberKnife, Radixact, or Vero4DRT are an advanced robotic radiotherapy device used to deliver stereotactic body radiotherapy (SBRT). The internal target volume (ITV) of lung tumors is assessed through a fiducial marker fusion using four‐dimensional computed tomography (CT). It is important to minimize the ITV to protect normal lung tissue from exposure to radiation and the associated side effects post SBRT. However, the ITV may alter if there is a change in the position of the fiducial marker with respect to the tumor. This study investigated the relationship between fiducial marker position and the ITV in order to prevent radiation exposure of normal lung tissue, and correct target coverage.

Materials and methods

This study retrospectively reviewed 230 lung cancer patients who received a fiducial marker for SBRT between April 2015 and September 2021. The distance of the fiducial marker to the gross tumor volume (GTV) in the expiratory (d_ex) and inspiratory (d_in) CT, and the ratio of the ITV/V(GTV_ex), were investigated.

Results

Upon comparing each lobe, although there was no significant difference in the d_diff and the ITV/V(GTV_ex) between all lobes for d_ex < 10 mm, there was significant difference in the d_diff and the ITV/V(GTV_ex) between the lower and upper lobes for d_ex ≥ 10 mm (p < 0.05). Moreover, there was significant difference in the d_diff and the ITV/V(GTV_ex) between d_ex ≥10 mm and d_ex < 10 mm in all lung regions (p < 0.05).

Conclusion

The ITV that had no margin from GTVs increased when d_ex was ≥10 mm for all lung regions (p < 0.05). Furthermore, the increase in ITV tended to be greater in the lower lung lobe. These findings can help decrease the possibility of adverse events post SBRT, and correct target coverage.

Predicting factors of symptomatic radiation pneumonitis induced by durvalumab following concurrent chemoradiotherapy in locally advanced non-small cell lung cancer

Background

Concurrent chemoradiotherapy (CCRT) followed by durvalumab is the standard of care for unresectable locally-advanced non-small cell carcinoma (LA-NSCLC). However, a major concern about administration of durvalumab after CCRT is whether the incidence of symptomatic radiation pneumonitis (RP) may increase or not. In the present analysis, we report the initial results of CCRT followed by durvalumab in patients with LA-NSCLC in a real-world setting with focus on predicting factors for symptomatic RP.

Methods

Patients who were pathologically diagnosed as NSCLC and initiated treatment with CCRT followed by durvalumab between July 2018 to December 2019 were eligible for this study. Patients were included if they completed the planned CRT course and administered at least one course of durvalumab. We retrospectively investigated the preliminary survival outcome and incidence and predicting factors for symptomatic RP.

Results

Of the 67 patients who planned CCRT, 63 patients completed the entire CCRT course. Of these, 56 patients proceeded to consolidation with durvalumab. The median time to eternal discontinuation of durvalumab was 9.7 months. The cumulative proportion of the patients who exhibited symptomatic RP was 30, 40 and 44% at 3, 6 and 12 months, respectively. In multivariate analyses, pulmonary fibrosis score and lung V40 were significant predictive factors for symptomatic RP (p < 0.001, HR: 7.83, 95% CI: 3.38–18.13, and p = 0.034, HR: 3.17, 95% CI: 1.09–9.19, respectively).

Conclusions

Pulmonary fibrosis sore and lung V40 were significant predictive factors for symptomatic RP. We should be cautious about the administration of durvalumab for patients having subclinical pulmonary fibrosis. To our best knowledge, this is one of the first report showing the predictive value of high dose volumes to the lung in patients with LA-NSCLC who received CCRT followed by durvalumab.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-021-01979-z.

High accuracy spectroscopy of 3- and 4-body Λ hypernuclei at Jefferson Lab

JLab E12-19-002 Experiment is planned to measure the Λ-binding energies of 3ΛH [Jπ = 1/2+ or 3/2+(T = 0)] and 4ΛH (1+) at JLab Hall C. The expected accuracy for the binding-energy measurement is |ΔBtotal Λ | ≃ 70 keV. The accurate spectroscopy for these light hypernuclei would shed light on the puzzle of the small binding energy and short lifetime of 3ΛH, and the chargesymmetry breaking in the ΛN interaction. We aim to perform the experiment in 2025.

Study of Λn FSI with Λ quasi-free productions on the 3H(e, e′K+)X reaction at JLab

Abstract. An nnΛ is a neutral baryon system with no charge. The study of the pure Λ-neutron system such as nnΛ gives us information on the Λn interaction. The nnΛ search experiment (E12-17-003) was performed at JLab Hall A in 2018. In this article, the Λn FSI was investigated by a shape analysis of the 3H(e, e′K+)X missing mass spectrum, and a preliminary result for the Λn FSI study is given.

Cross-section measurement of virtual photoproduction of iso-triplet three-body hypernucleus, Λnn

Missing-mass spectroscopy with the 3H(e, e′K+) reaction was carried out at Jefferson Lab’s (JLab) Hall A in Oct–Nov, 2018. The differential cross section for the 3H(γ∗, K+)Λnn was deduced at ω = Ee − Ee′ = 2.102 GeV and at the forward K+-scattering angle (0° ≤ θγ∗K ≤ 5°) in the laboratory frame. Given typical predicted energies and decay widths, which are (BΛ, Γ) = (−0.25, 0.8) and (−0.55, 4.7) MeV, the cross sections were found to be 11.2 ± 4.8(stat.)+4.1−2.1(sys.) and 18.1 ± 6.8(stat.)+4.2−2.9(sys.) nb/sr, respectively. The obtained result would impose a constraint for interaction models particularly between Λ and neutron by comparing to theoretical calculations.

Study of the Λ/Σ0 electroproduction in the low-Q2 region at JLab

We performed an experiment using tritium and hydrogen cryogenic gas targets at Thomas Jefferson National Accelerator Facility (JLab) in 2018 (E12-17-003)[1, 2]. In this article, we discuss the Λ/Σ0 hyperon electroproduction from hydrogen target. Elementary Λ/Σ0 hyperon production processes are important not only for an absolute mass scale calibration in our experiment, but also for the study of the electroproduction mechanisms themselves. In this article, we reported the results of the differential cross section for the p(e, e’K+)Λ/Σ0 reaction at Q2 ∼ 0.5 (GeV/c)2.

Outcomes of robot-assisted versus conventional laparoscopic low anterior resection in patients with rectal cancer: propensity-matched analysis of the National Clinical Database in Japan

BACKGROUND

Robot-assisted laparoscopic surgery has several advantages over conventional laparoscopy. However, population-based comparative studies for low anterior resection are limited. This article aimed to compare peri-operative results of robot-assisted low anterior resection (RALAR) and laparoscopy.

METHODS

This retrospective cohort study used data from patients treated with RALAR or conventional laparoscopic low anterior resection (CLLAR) between October 2018 and December 2019, as recorded in the Japanese National Clinical Database, a data set registering clinical information, perioperative outcomes, and mortality. Of note, the registry does not include information on the tumour location (centimetres from the anal verge) and diverting stoma creation. Perioperative outcomes, including rate of conversion to open surgery, were compared between RALAR and CLLAR groups. Confounding factors were adjusted for using propensity score matching.

RESULTS

Of 21 415 patients treated during the study interval, 20 220 were reviewed. Two homogeneous groups of 2843 patients were created by propensity score matching. The conversion rate to open surgery was significantly lower in the RALAR group than in the CLLAR group (0.7 versus 2.0 per cent; P < 0.001). The RALAR group had a longer operating time (median: 352 versus 283 min; P < 0.001), less intraoperative blood loss (15 versus 20 ml; P < 0.001), a lower in-hospital mortality rate (0.1 versus 0.5 per cent; P = 0.007), and a shorter postoperative hospital stay (median: 13 versus 14 days; P < 0.001) compared with the CLLAR group. The CLLAR group had a lower rate of readmission within 30 days (2.4 versus 3.3 per cent; P = 0.045).

CONCLUSION

These data highlight the reduced conversion rate, in-hospital mortality rate, intraoperative blood loss, and length of postoperative hospital stay for rectal cancer surgery in patients treated using robot-assisted laparoscopic surgery compared with laparoscopic low anterior resection.

Plan comparison of prostate stereotactic radiotherapy in spacer implant patients

In prostate stereotactic body radiation therapy (SBRT), hydrogel spacers are increasingly used. This study aimed to perform a dosimetry comparison of treatment plans using CyberKnife (CK), commonly used for prostate SBRT, Helical TomoTherapy (HT), and TrueBeam (TB) in patients with hydrogel spacer implantations. The data of 20 patients who received hydrogel spacer implantation for prostate SBRT were retrospectively analyzed. The prescription dose was 36.25 Gy in five fractions to 95% of the planning target volume (PTV; D95). The conformity index (CI), gradient index (GI), homogeneity index (HI), and dose‐volume histogram (DVH) were analyzed for the three modalities, using the same PTV margins. The monitor unit (MU) and the beam‐on‐time (BOT) values were subsequently compared. The CI of TB (0.93 ± 0.02) was significantly superior to those of CK (0.82 ± 0.03, p < 0.01) and HT (0.86 ± 0.03, p < 0.01). Similarly, the GI value of TB (3.59 ± 0.12) was significantly better than those of CK (4.31 ± 0.43, p < 0.01) and HT (4.52 ± 0.24, p < 0.01). The median doses to the bladder did not differ between the CK and TB (V18.1 Gy: 16.5% ± 4.5% vs. 15.8% ± 4.4%, p = 1.00), but were significantly higher for HT (V18.1 Gy: 33.2% ± 7.3%, p < 0.01 vs. CK, p < 0.01 vs. TB). The median rectal dose was significantly lower for TB (V18.1 Gy: 5.6% ± 4.5%) than for CK (V18.1 Gy: 11.2% ± 6.7%, p < 0.01) and HT (20.2% ± 8.3%, p < 0.01). TB had the shortest BOT (2.6 min; CK: 17.4 min, HT: 6.9 min). TB could create treatment plans dosimetrically comparable to those of CK when using the same margins, in patients with hydrogel spacers.

Rectal cancer lateral lymph nodes: multicentre study of the impact of obturator and internal iliac nodes on oncological outcomes

BACKGROUND

In patients with rectal cancer, enlarged lateral lymph nodes (LLNs) result in increased lateral local recurrence (LLR) and lower cancer-specific survival (CSS) rates, which can be improved with (chemo)radiotherapy ((C)RT) and LLN dissection (LLND). This study investigated whether different LLN locations affect oncological outcomes.

METHODS

Patients with low cT3-4 rectal cancer without synchronous distant metastases were included in this multicentre retrospective cohort study. All MRI was re-evaluated, with special attention to LLN involvement and response.

RESULTS

More advanced cT and cN category were associated with the occurrence of enlarged obturator nodes. Multivariable analyses showed that a node in the internal iliac compartment with a short-axis (SA) size of at least 7 mm on baseline MRI and over 4 mm after (C)RT was predictive of LLR, compared with a post-(C)RT SA of 4 mm or less (hazard ratio (HR) 5.74, 95 per cent c.i. 2.98 to 11.05 vs HR 1.40, 0.19 to 10.20; P < 0.001). Obturator LLNs with a SA larger than 6 mm after (C)RT were associated with a higher 5-year distant metastasis rate and lowered CSS in patients who did not undergo LLND. The survival difference was not present after LLND. Multivariable analyses found that only cT category (HR 2.22, 1.07 to 4.64; P = 0.033) and margin involvement (HR 2.95, 1.18 to 7.37; P = 0.021) independently predicted the development of metastatic disease.

CONCLUSION

Internal iliac LLN enlargement is associated with an increased LLR rate, whereas obturator nodes are associated with more advanced disease with increased distant metastasis and reduced CSS rates. LLND improves local control in persistent internal iliac nodes, and might have a role in controlling systemic spread in persistent obturator nodes.Members of the Lateral Node Study Consortium are co-authors of this study and are listed under the heading Collaborators.

Beneficial effects of balloon pulmonary angioplasty on clinical outcomes in patients with residual pulmonary hypertension after pulmonary endarterectomy

Background

Although pulmonary endarterectomy (PEA) is an established surgical treatment for chronic thromboembolic pulmonary hypertension (CTEPH), a part of patients after PEA show residual pulmonary hypertension, leading to limited exercise capacity. Recently, several studies have indicated that balloon pulmonary angioplasty (BPA) improves hemodynamics, exercise capacity and prognosis in inoperable CTEPH patients. However, the effects of BPA in patients with residual pulmonary hypertension after PEA remain to be elucidated.

Aim

In the present study, we investigated comprehensive efficacy of BPA on hemodynamics, exercise capacity and right ventricular function in those with residual pulmonary hypertension after PEA.

Methods

From October 2010 to February 2019, 227 patients with CTEPH underwent PEA in our institution. Right heart catheterization after PEA (median follow up period from PEA to right heart catheterization 39 [10.5, 90] months) showed that 55 patients showed residual PH (mean pulmonary artery pressure (mPAP)≥25mmHg), and 38 of them referred to BPA (mean age 57 years old, male 8 (21%)) due to residual symptoms. In 29 out of 38 patients (76%) who completed BPA and underwent follow-up right heart catheterization, we examined hemodynamics, exercise capacity and right ventricular function before and after BPA. Follow-up examination was performed 3 months after last BPA session.

Results

In this study population (N=29), PEA significantly improved mPAP (47±7 to 38±10 mmHg), pulmonary vascular resistance (PVR, 14.6±4.6 to 9.2±4.6 WU) and right ventricular ejection fraction measured by magnetic resonance imaging (26.6±11.3 to 38.4±6.8%) (Figure). Median period from PEA to first BPA procedure was 42 [13.5, 94] months. Total session number during study period was 160 sessions, and mean session number of BPA was 5.5±1.5 per patient. Follow-up study revealed that BPA additionally improved mPAP (38±10 to 27±8 mmHg) and PVR (9.2±4.6 to 5.1±2.2 WU) (Figure). Similarly, 6-minute walk distance (393±125 to 452±125 m) and peak VO2 (16.4±3.8 to 18.1±4.6 ml/min/kg, p&lt;0.05) were increased, and WHO functional class also significantly improved by BPA (I/II/III/IV, 0/21/8/ 0 to 1/27/1/0, p&lt;0.01). In addition, right ventricular ejection fraction (38.4±6.8 to 44.2±7.1%) was increased after BPA (Figure). There were no procedure-related deaths and major lung injuries requiring oral intubation during study period. 3-year survival in patients after BPA was 100% (median follow-up period after last BPA session, 32 [18, 46] months).

Conclusion

In CTEPH patients with residual pulmonary hypertension after PEA, additional BPA significantly improved hemodynamics, right ventricular function, exercise capacity and residual symptoms without severe complications, leading to good prognosis. These results suggest that combination therapy of PEA and BPA could be an effective therapeutic option for post PEA patients with residual symptoms and exercise limitation.

Figure 1

Funding Acknowledgement

Type of funding source: None

Simultaneous pelvic exenteration and liver resection for primary rectal cancer with synchronous liver metastases: results from the PelvEx Collaborative

AIM

At presentation, 15-20% of patients with rectal cancer already have synchronous liver metastases. The aim of this study was to determine the surgical and survival outcomes in patients with advanced rectal cancer who underwent combined pelvic exenteration and liver (oligometastatic) resection.

METHOD

Data from 20 international institutions that performed simultaneous pelvic exenteration and liver resection between 2007 and 2017 were accumulated. Primarily, we examined perioperative outcomes, morbidity and mortality. We also assessed the impact that margin status had on survival.

RESULTS

Of 128 patients, 72 (56.2%) were men with a median age of 60 years [interquartile range (IQR) 15 years]. The median size of the liver oligometastatic deposits was 2 cm (IQR 1.8 cm). The median duration of surgery was 406 min (IQR 240 min), with a median blood loss of 1090 ml (IQR 2010 ml). A negative resection margin (R0 resection) was achieved in 73.5% of pelvic exenterations and 66.4% of liver resections. The 30-day mortality rate was 1.6%, and 32% of patients had a major postoperative complication. The 5-year overall survival for patients in whom an R0 resection of both primary and metastatic disease was achieved was 54.6% compared with 20% for those with an R1/R2 resection (P = 0.006).

CONCLUSION

Simultaneous pelvic exenteration and liver resection is feasible, with acceptable morbidity and mortality. Simultaneous resection should only be performed where an R0 resection of both pelvic and hepatic disease is anticipated.

Retrospective assessment of a single fiducial marker tracking regimen with robotic stereotactic body radiation therapy for liver tumours

Aim

To investigate tumour motion tracking uncertainties in the CyberKnife Synchrony system with single fiducial marker in liver tumours.

Background

In the fiducial-based CyberKnife real-time tumour motion tracking system, multiple fiducial markers are generally used to enable translation and rotation corrections during tracking. However, sometimes a single fiducial marker is employed when rotation corrections are not estimated during treatment.

Materials and methods

Data were analysed for 32 patients with liver tumours where one fiducial marker was implanted. Four-dimensional computed tomography (CT) scans were performed to determine the internal target volume (ITV). Before the first treatment fraction, the CT scans were repeated and the marker migration was determined. Log files generated by the Synchrony system were obtained after each treatment and the correlation model errors were calculated. Intra-fractional spine rotations were examined on the spine alignment images before and after each treatment.

Results

The mean (standard deviation) ITV margin was 4.1 (2.3) mm, which correlated weakly with the distance between the fiducial marker and the tumour. The mean migration distance of the marker was 1.5 (0.7) mm. The overall mean correlation model error was 1.03 (0.37) mm in the radial direction. The overall mean spine rotations were 0.27° (0.31), 0.25° (0.22), and 0.23° (0.26) for roll, pitch, and yaw, respectively. The treatment time was moderately associated with the correlation model errors and weakly related to spine rotation in the roll and yaw planes.

Conclusions

More caution and an additional safety margins are required when tracking a single fiducial marker.

Abstract P5-01-03: Comparison of mammography findings between dense and non dense breast in Japanese subjects: The potential limitation of routine mammography

Introduction

Recently “Dense breast” has attracted numerous attention because of diagnostic difficulty in mammography among those harboring dense breast, which is far more frequent in Asian than Caucasian women. Therefore, in this study, we retrospectively evaluated the risks of subsequent development of malignancy through comparing the detailed mammographic characteristics between Japanese subjects harboring dense and non dense breasts.

Methods

We retrospectively examined mammorgraphic findings taken from March 2013 to March 2016 at Nahanishi Clinic, Okinawa, Japan. We stratified its density according to the suggestion of the Japan Central Organization on Quality Assurance of Breast Cancer Screening, which was defined by the proportion of fat area as follows; extremely high dense:10-20%, heterogeneously dense:40-50%, scattered fatty:70-90%, fatty: almost all the breast fat. “Dense breast” includes extremely high and heterogeneous dense. We evaluated the detailed radiological findings of each phenotypes including the characteristics of the mass, calcification and focal asymmetric density(FAD) and architectural distortion. We also compared the rates of subsequent cancer development and sensitivity of detecting cancer between those harboring dense and non dense breasts.

Results

We reviewed the mammography findings of 7747 Japanese women including 857 with breast cancers. When adjusted for age, the rate of dense breast was significantly associated with age, 88.6% in women in their 20s(vs40s p&lt;0.001 OR3.402), with incremental decrease, 80.4% in 30s(P&lt;0.001 OR1.802), 69.5% in 40s, 55.9% in 50s(P&lt;0.001 OR0.512), 32.3% in 60s(P&lt;0.001 OR 0.108), 19.5% in 70s(P&lt;0.001 OR 0.106) and 5.3% in over 80s(P&lt;0.001 OR0.024). The rate of malignancies was 9.1% (385) in dense and 13.6% (472) in non dense breasts. We then compared the mammographic findings between dense and non dense breast. Abnormal calcifications were detected more frequent(7.6%vs5.3% P&lt;0.001 OR1.478) but masses less so(16.4%vs23.7% P&lt;0.001 OR 0.632) in dense breast, while no significant differences detected in FADs(4.9%vs4.6% P=0.35 OR1.074) and distortions(1.2%vs1.4% P=0.29 OR=0.859) between dense and non dense breast. The rate of carcinoma was less frequent in dense breast among those associated with mammographic calcification(19%vs27.3% P&lt;0.01 OR0.626) but more frequently in dense breast among those with masses (13%vs19% P&lt;0.001 OR0.628). The rate of carcinoma was not different between dense and non dense breast in those with FADs (21.6vs20.6% P=0.72 OR1.067) and distortions(71.7%vs74.7% P=0.64 OR0.857). In addition, among 37 breast cancer patients who did not harbor the mammographic findings above (26 dense and 11 non dense breasts), the average mass length was significantly larger in dense (13.6mm) than non-dense breast (9.9mm) (P=0.018 used Welch's t test), respectively.

Conclusion

Results of our present study did demonstrate that detection of malignancy in those with mammographic dense breast is more difficult. Therefore, in those harboring dense breast in mammography, addition of other modalities such as US could improve the detection of breast carcinoma.

Citation Format: Takigami N, Tamaki K, Kamada Y, Uehara K, Terukina S, Ishida T, Miyashita M, McNamara KM, Tamaki N, Sasano H. Comparison of mammography findings between dense and non dense breast in Japanese subjects: The potential limitation of routine mammography [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-01-03.

Abstract P6-11-01: Final results of the randomized trial of exercise intervention vs. usual care for breast cancer patients with aromatase inhibitor to prevent and improve the aromatase inhibitor induced arthralgia

Aromatase inhibitors (AIs) have been used in the adjuvant treatment of postmenopausal women with hormone receptor positive early breast cancer as a consequence of the significant benefit in DFS and OS when compared with tamoxifen. However the patients who receive AIs have an increased risk of arthralgia, at most 50% of patients did not take AIs and the 20% of the discontinued patients were within the first year of use. The HOPE study demonstrated that exercise was effective in improving AI-induced arthralgia. We conducted the AIAI (Arthralgia Improvement for the patients with Aromatase Inhibitors) study using wider eligibility criteria that the HOPE study to assess the impact on AI induced arthralgia in breast cancer patients.

Patients were randomly assigned, in a 3:1 ratio, to exercise intervention or usual care. Following randomization participants could choose from 3 types of exercise including group 1 (120-150 minutes per week of walking or running), group 2 (daily NIPPON HOSO KYOKAI: NHK broadcast exercise in Japan) and group 3 (going up the stairs- frequency, etc). The primary endpoint was the arthralgia change at 6 and 12 months, which was assessed using the BPI (Brief Pain Inventory). Secondary endpoints included the BPI according to the completion rate of exercise (70% and more or less than 70%), the BPI change of the patients with arthralgia (the patients who had arthralgia at the time they enrolled this study; BPI worst pain 3≤), the BPI of the each exercise group, the BPI according to the duration of AIs therapy (24 months and more or less than 24 months), the correlation between the BMI change and the BPI change, adherence of AIs and safety.

102 were randomly assigned to exercise intervention group (22 patients dropped out of this study) and 37 to usual care group (9 patients dropped out of this study).Trends for differentiations of pain interference at 12 months was detected between exercise intervention group and usual care group, but the differences did not reach statistical significance (p = .067). There was statistically better pain interference of the 70% and more exercise completion group than the usual care group at 12 months (-0.29±1.22 for exercise intervention group and 0.33±0.88 for usual care group, p= .002). The change of pain interference was statistically better for the exercise intervention group than the usual care group at 12 months (p= .017, -0.61±0.69 for exercise intervention group and 1.14±1.56 for usual care group). There was statistically significant difference of pain interference between group 1 exercise intervention group and the usual care group at 12 months (-0.14±0.68 for group 1 exercise intervention group and 0.33±0.88 for the usual care group, p= .009). Tendencies were detected in the AIs therapy less than 24 months group. Trends for the correlation between BPI and BMI were detected in worst pain at 6 month, pain severity at 6 month and pain interference at 12 month. There was a statistically significant difference of AIs adherence between the exercise intervention group (99%) and the usual care group (92%) (P=0.03).

Exercise may be effective in improving and preventing AI-induced arthralgia.

Citation Format: Tamaki K, Takaesu M, Nagamine S, Terukina S, Kamada Y, Uehara K, Takigami N, Arakaki M, Yamashiro K, Miyashita M, Ishida T, McNamara KM, Tamaki N, Sasano H. Final results of the randomized trial of exercise intervention vs. usual care for breast cancer patients with aromatase inhibitor to prevent and improve the aromatase inhibitor induced arthralgia [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-11-01.

Identification of the suitable leaf margin for liver stereotactic body radiotherapy with flattening filter-free beams

The purpose of this study is to identify the suitable leaf margin for liver stereotactic body radiotherapy (SBRT) with flattening filter-free (FFF) beams, as compared with that with flattening filter (FF) beams. SBRT treatment planning for 10 patients with liver cancer was performed using 10-MV FFF and FF beams obtained from a Varian TrueBeam (Varian Medical Systems, Palo Alto, CA) linear accelerator. Each plan was generated with the leaf margin to the planning target volume (PTV) ranging from -3 to 5 mm. The prescription dose at D95 (dose covering 95% of the volume) was 48 Gy in 4 fractions to the PTV. The following dosimetric parameters were evaluated quantitatively: homogeneity index (HI), conformity index (CI), gradient index (GI), the normal liver receiving a dose greater than or equal to 20 Gy (V20), and the mean normal liver dose. The HI for FFF and FF beams increased as the leaf margin decreased. The leaf margins that achieved the best CI and GI were 0.1 and -0.3 mm for FFF beams, and 0.1 and -0.9 mm for FF beams. The liver V20 and the mean liver dose reached their minimum values at leaf margins of -0.8 and 0.0 mm for FFF beams, and -0.8 and 0.0 mm for FF beams. The suitable leaf margin for SBRT planning did not differ significantly for FFF and FF beams. Our data showed that, for both FFF and FF beams, a leaf margin of 0 or -1 mm was optimal for liver SBRT planning in terms of both target coverage and normal tissue sparing.

Efficacy of protocol-based pharmacotherapy management on anticoagulation with warfarin for patients with cardiovascular surgery

WHAT IS KNOWN AND OBJECTIVE

Anticoagulation therapy with warfarin requires periodic monitoring of prothrombin time-international normalized ratio (PT-INR) and adequate dose adjustments based on the data to minimize the risk of bleeding and thromboembolic events. In our hospital, we have developed protocol-based pharmaceutical care, which we called protocol-based pharmacotherapy management (PBPM), for warfarin therapy. The protocol requires pharmacists to manage timing of blood sampling for measuring PT-INR and warfarin dosage determination based on an algorithm. This study evaluated the efficacy of PBPM in warfarin therapy by comparing to conventional pharmaceutical care.

METHODS

From October 2013 to June 2015, a total of 134 hospitalized patients who underwent cardiovascular surgeries received post-operative warfarin therapy. The early series of patients received warfarin therapy as the conventional care (control group, n=77), whereas the latter received warfarin therapy based on the PBPM (PBPM group, n=68). These patients formed the cohort of the present study and were retrospectively analysed.

RESULTS

The indications for warfarin included aortic valve replacement (n=56), mitral valve replacement (n=4), mitral valve plasty (n=22) and atrial fibrillation (n=29). There were no differences in patients' characteristics between both groups. The percentage time in therapeutic range in the first 10 days was significantly higher in the PBPM group (47.1%) than that in the control group (34.4%, P<.005). The average time to reach the steady state was significantly (P<.005) shorter in the PBPM group compared to the control group (7.3 vs 8.6 days).

WHAT IS NEW AND CONCLUSION

Warfarin therapy based on our novel PBPM was clinically safe and resulted in significantly better anticoagulation control compared to conventional care.

Abstract P5-12-01: Randomized trial of exercise intervention vs. usual care for breast cancer patients with aromatase inhibitor to prevent and improve the aromatase inhibitor induced arthralgia

Purpose: Arthralgia sometimes occurs in the breast cancer patients treated with aromatase inhibitors (AIs). It is one of the most important reasons for poor AIs adherence.

Background; The HOPE study previously demonstrated that exercise was effective in improving AI-induced arthralgia in breast cancer patients. However, recruitment to this study was limited to severe cases (Criteria; physically inactive, &gt;6 months AT treatment, &gt;2 months arthralgia). To asses if these findings were more generalizable to all breast cancer contexts we conducted a randomized trial of exercise intervention using wider eligibility criteria that the hope study to assess the impact on AI induced arthralgia in breast cancer patients.

Methods: We examined Japanese breast cancer patients operated at Nahanishi Clinic, Okinawa, Japan. Following the informed consent the patients were randomly assigned to a 3:1 ratio to exercise intervention or usual care, . Eligibility criteria included receiving an AI for 0-4 years, no metastases, any arthralgia level and any exercise habits. Following randomization participants could choose from 3 types of exercise including strong (120-150 minutes per week of walking or running), intermediate (gentle calisthenics (daily NIPPON HOSO KYOKAI: NHK broadcast exercise)) and weak (going up the stairs- frequency). Arthralgia was assessed using the Brief Pain Inventory (BPI), in which the patients completed a baseline, 6month and 12 month BPI assessment. Primary endpoint was BPI change at 12 months.

Results: Among 227 women screened, we randomized 108 women, with 80 to exercise intervention (46 of strong, 19 of intermediate and 15 of weak) and 28 to usual care. Base line BPI were well balanced between exercise intervention and usual care. Overall exercise intervention reduced BPI scores relative to control. The BPI changes of worst pain, least pain, average pain and pain right now were 0.09, -0.25, -0.14 and 0 for exercise intervention group and 0.21, 0.46, 0.07 and 0.61 for usual care group, respectively. There was a statistically significant difference of AIs adherence between exercise intervention group (99%) and usual care group (92%) (P=0.03).

Conclusion: Exercise intervention tends to improve the AI-induced arthralgia and has a positive effect on AIs adherence.

Citation Format: Tajaesu M, Tamaki K, Nagamine S, Kamada Y, Uehara K, Arakaki M, Tamatsu Y, Yamashiro K, Miyashita M, Ishida T, Ohuchi N, McNamara K, Terukina S, Sasano H, Tamaki N. Randomized trial of exercise intervention vs. usual care for breast cancer patients with aromatase inhibitor to prevent and improve the aromatase inhibitor induced arthralgia [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-12-01.

Early results of multicenter phase II trial of perioperative oxaliplatin and capecitabine without radiotherapy for high-risk rectal cancer: CORONA I study

BACKGROUNDS

Perioperative introduction of developed chemotherapy into the treatment strategy for locally advanced rectal cancer (LARC) may be a promising option. However, the most prevalent treatment for high-risk LARC remains preoperative chemoradiotherapy (CRT) in Western countries.

PATIENTS AND METHODS

A phase II trial was undertaken to evaluate safety and efficacy of perioperative XELOX without radiotherapy (RT) for patients with high-risk LARC. Patients received 4 cycles of XELOX before and after surgery, respectively. Primary endpoint was disease-free survival.

RESULTS

We enrolled 41 patients between June 2012 and April 2014. The completion rate of the preoperative XELOX was 90.3%. Twenty-nine patients (70.7%) could start postoperative XELOX, 15 of these patients (51.7%) completed 4 cycles. Allergic reaction to oxaliplatin was experienced by 5 patients (17.2%) during postoperative XELOX. One patient received additional RT after preoperative XELOX. Consequently, the remaining 40 patients underwent primary resection. Major complications occurred in 6 of 40 patients (15.0%). Pathological complete response (pCR) rate was 12.2%, and good tumor regression was exhibited in 31.7%. N down-staging (cN+ to ypN0) and T down-staging were detected in 56.7% and 52.5%, respectively. Clinical T4 tumor was a predictor of poor pathological response (p < 0.001).

CONCLUSIONS

We could show the favorable pCR rate after preoperative XELOX alone. However, the T and N down-staging rate was likely to be insufficient. When tumor regression is essential for curative resection, the use of preoperative CRT is likely to be recommended. For patients with massive LN metastasis, the additional Bev to NAC might be a promising option.

Clinical significance of dual-energy CT-derived iodine quantification in the diagnosis of metastatic LN in colorectal cancer

BACKGROUND

The purpose of this study was to evaluate the diagnostic value of dual-energy computed tomography (DECT) in detecting lymph node (LN) metastasis in patients with colorectal cancer.

METHODS

Data from 81 LNs from 28 patients with colorectal adenocarcinoma were retrospectively analyzed. All patients received DECT before surgery without any neoadjuvant therapy. The diagnostic value was assessed using the iodine concentration (IC).

RESULTS

In the pathological findings, 35 (43.2%) LNs from 13 patients were metastatic and 46 (56.8%) LNs from 17 patients were non-metastatic. The mean IC of metastatic LNs in the portal venous phase (PP) was 1.60 mg/ml, which was significantly lower compared with non-metastatic LNs (3.25 mg/ml, p < 0.001). Receiver operating characteristic (ROC) analysis revealed that the IC in PP had the highest ability to discriminate LN metastasis (area under the ROC curve [AUC] 0.932). The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of IC in PP (cutoff 2.1 mg/ml) were 87.0%, 88.6%, 85.3%, 90.0%, and 87.9%, respectively. When clinically obvious metastatic LNs in conventional CT findings were excluded, 50 LNs remained (5 metastatic and 45 non-metastatic LNs). In this subgroup analysis, the IC in PP remained the most powerful predictor of metastatic LNs (cutoff: 2.1 mg/ml, AUC 0.933).

CONCLUSIONS

The evaluation of IC in DECT may improve the diagnostic capabilities of discriminating metastatic LNs. This method may be particularly useful when conventional CT findings lead to equivocal results.

An internally and externally validated nomogram for predicting the risk of irinotecan-induced severe neutropenia in advanced colorectal cancer patients

Background:

In Asians, the risk of irinotecan-induced severe toxicities is related in part to UGT1A1*6 (UGT, UDP glucuronosyltransferase) and UGT1A1*28, variant alleles that reduce the elimination of SN-38, the active metabolite of irinotecan. We prospectively studied the relation between the UGT1A1 genotype and the safety of irinotecan-based regimens in Japanese patients with advanced colorectal cancer, and then constructed a nomogram for predicting the risk of severe neutropenia in the first treatment cycle.

Methods:

Safety data were obtained from 1312 patients monitored during the first 3 cycles of irinotecan-based regimen in a prospective observational study. In development of the nomogram, multivariable logistic regression analysis was used to test the associations of candidate factors to severe neutropenia in the first cycle. The final nomogram based on the results of multivariable analysis was constructed and validated internally using a bootstrapping technique and externally in an independent data set (n=350).

Results:

The UGT1A1 genotype was confirmed to be associated with increased risks of irinotecan-induced grade 3 or 4 neutropenia and diarrhoea. The final nomogram included type of regimen, administered dose of irinotecan, gender, age, UGT1A1 genotype, Eastern Cooperative Oncology Group performance status, pre-treatment absolute neutrophil count, and total bilirubin level. The model was validated both internally (bootstrap-adjusted concordance index, 0.69) and externally (concordance index, 0.70).

Conclusions:

Our nomogram can be used before treatment to accurately predict the probability of irinotecan-induced severe neutropenia in the first cycle of therapy. Additional studies should evaluate the effect of nomogram-guided dosing on efficacy in patients receiving irinotecan.

Necrotising soft-tissue infections of the upper limb: risk factors for amputation and death

Necrotising soft-tissue infections (NSTIs) of the upper limb are uncommon, but potentially life-threatening. We used a national database to investigate the risk factors for amputation of the limb and death. We extracted data from the Japanese Diagnosis Procedure Combination database on 116 patients (79 men and 37 women) who had a NSTI of the upper extremity between 2007 and 2010. The overall in-hospital mortality was 15.5%. Univariate analysis of in-hospital mortality showed that the significant variables were age (p = 0.015), liver dysfunction (p = 0.005), renal dysfunction (P < 0.001), altered consciousness (p = 0.049), and sepsis (p = 0.021). Logistic regression analysis showed that the factors associated with death in hospital were age over 70 years (Odds Ratio (OR) 6.6; 95% confidence interval (CI) 1.5 to 28.2; p = 0.011) and renal dysfunction (OR 15.4; 95% CI 3.8 to 62.8; p < 0.001). Univariate analysis of limb amputation showed that the significant variables were diabetes (p = 0.017) mellitus and sepsis (p = 0.001). Multivariable logistic regression analysis showed that the factors related to limb amputation were sepsis (OR 1.8; 95% CI 1.5 to 24.0; p = 0.013) and diabetes mellitus (OR 1.6; 95% CI 1.1 to 21.1; p = 0.038). For NSTIs of the upper extremity, advanced age and renal dysfunction are both associated with a higher rate of in-hospital mortality. Sepsis and diabetes mellitus are both associated with a higher rate of amputation.

Aggressive surgical treatment with bony pelvic resection for locally recurrent rectal cancer

BACKGROUND

In the current era of total mesorectal excision, local relapse remains a main cause of recurrence. Although standard treatment for locally recurrent rectal cancer (LRRC) has not been established, R0 resection represents the only potentially curative treatment. However, extended surgery accompanying bony pelvic resection is technically demanding and is still challenging.

METHODS

Studied were 35 patients with LRRC who underwent combined resection of bony pelvis between August 2006 and October 2013. Safety and prognostic factors for survival were analyzed. Median follow-up was 33 months.

RESULTS

Sacrectomy was performed in 32 patients and 3 patients underwent combined resection of the pubis and ischium. The dominant operative procedure was total pelvic exenteration in 30 (86%) patients. R0 resection was achieved in 27 (77%) patients. No patients died. Pelvic sepsis was the most frequent complication (40%). Recurrence developed in 20 (57%), with the lung the most frequent site (10 patients). Three-year local relapse-free survival (LRFS) and disease-free survival (DFS) were 72.1% and 32.7%, respectively. On multivariate analysis, R1 resection was the only independent risk factor for local recurrence (p = 0.010), and concomitant liver metastasis and initial non sphincter-preserving surgery were independent predictors of worse DFS (p = 0.008 and p = 0.042, respectively).

CONCLUSIONS

Aggressive surgical treatment combined with bony resection for carefully selected patients with LRRC was safe with a high rate of R0 resection and favorable LRFS. However, DFS was not satisfactory even after R0 resection and the main cause was lung metastasis. Preventing distant recurrence might be a key to improve survival.