The value of additional electrodes when stereo-electroencephalography is inconclusive.

OBJECTIVE: Stereo-electroencephalography (SEEG) is the preferred method for intracranial localization of the seizure-onset zone (SOZ) in drug-resistant focal epilepsy. Occasionally SEEG evaluation fails to confirm the pre-implantation hypothesis. This leads to a decision tree regarding whether the addition of SEEG electrodes (two-step SEEG - 2sSEEG) or placement of subdural electrodes (SDEs) after SEEG (SEEG2SDE) would help. There is a dearth of literature encompassing this scenario, and here we aimed to characterize outcomes following unplanned two-step intracranial EEG (iEEG). METHODS: All 225 adult SEEG cases over 8 years at our institution were reviewed to extract patient data and outcomes following a two-step evaluation. Three raters independently quantified benefits of additional intracranial electrodes. The relationship between two-step iEEG benefit and clinical outcome was then analyzed. RESULTS: Fourteen patients underwent 2sSEEG and nine underwent SEEG2SDE. In the former cohort, the second SEEG procedure was performed for these reasons-precise localization of the SOZ (36%); defining margins of eloquent cortex (21%); and broadening coverage in the setting of non-localizable seizure onsets (43% of cases). Sixty-four percent of 2sSEEG cases were consistently deemed beneficial (Light's κ = 0.80). 2sSEEG performed for the first two indications was much more beneficial than when onsets were not localizable (100% vs 17%, p = .02). In the SEEG2SDE cohort, SDEs identified the SOZ and enabled delineation of margins relative to eloquent cortex in all cases. SIGNIFICANCE: The two-step iEEG is useful if the initial evaluation is broadly concordant with the original electroclinical hypothesis, where it can clarify onset zones or delineate safe surgical margins; however, it provides minimal benefit when the implantation hypothesis is erroneous, and we recommend that 2sSEEG not be generally utilized in such cases. SDE implantation after SEEG minimizes the need for SDEs and is helpful in delineating surgical boundaries relative to ictal-onset zones and eloquent cortex.

The role of radiation therapy in the management of primary retroperitoneal sarcoma: A systematic review and clinical practice guidelines from the Australia and New Zealand Sarcoma Association.

While surgery is the mainstay of treatment for localised retroperitoneal sarcoma, the use of radiotherapy (RT) remains controversial. This systematic review aimed to evaluate the role of RT for retroperitoneal sarcoma. A systematic review using the population, intervention, comparison, and outcome model from 1990 to 2022 identified 66 studies (a mixture of preoperative and postoperative RT); one randomised controlled trial (RCT) with two publications, 18 registry studies, and 46 retrospective studies. In the RCT of preoperative RT, there was no difference in local/abdominal recurrence. The pooled analysis of this RCT and a retrospective study showed a significant abdominal recurrence free survival benefit with preoperative RT in low grade liposarcoma. The RCT and the majority of retrospective series found RT did not improve recurrence free survival (11 of 16 no difference in combined local and distant RFS, 11 of 13 no difference in distant metastasis free survival), disease specific survival (9 of 12 studies) or overall survival (33 of 49 studies). The majority of studies found no association between RT and perioperative morbidity. In summary, preoperative RT may improve local control for low grade (well-differentiated or grades 1-2 dedifferentiated) liposarcoma, but not other histological subtypes. There is no strong evidence that perioperative RT provides an overall survival benefit. Patients with low grade retroperitoneal liposarcoma can be considered for preoperative RT to improve abdominal recurrence free survival. The rationale and level of evidence in this scenario should be carefully discussed by the multidisciplinary team with patients. RT should not be routinely recommended for other histological subtypes.

Enhanced Surgeons: Understanding the Design of Augmented Reality Instructions for Keyhole Surgery.

It is important to understand how to design AR content for surgical contexts to mitigate the risk of distracting the surgeons. In this work, we test information overlays for AR guidance during keyhole surgery. We performed a preliminary evaluation of a prototype, focusing on the effects of colour, opacity, and information representation. Our work contributes insights into the design of AR guidance in surgery settings and a foundation for future research on visualisation design for surgical AR.

Comparison of three analgesic regimens in women undergoing cervical brachytherapy.

PURPOSE: Effective periprocedural analgesia is an important aspect of cervical brachytherapy delivery, with implications for patient comfort and attendance for subsequent fractions. We compared the efficacy and safety of three analgesic modalities: intravenous patient-controlled analgesia (IV-PCA), continuous epidural infusion (CEI) and programmed-intermittent epidural bolus with patient-controlled epidural analgesia (PIEB-PCEA). METHODS AND MATERIALS: Ninety-seven brachytherapy episodes involving 36 patients between July 2016 and June 2019 in a single tertiary center were retrospectively reviewed. Episodes were divided into two key phases: Phase 1 (while applicator remained in situ) and Phase 2 (following applicator removal until discharge or 4 h). For the primary endpoint, pain scores were retrieved and analyzed by analgesic modality with respect to median score and an internally defined "unacceptable" pain experience (>20% of scores being ≥4/10; i.e., moderate or greater). Total nonepidural oral morphine equivalent dose (OMED) and toxicity/complication events were reported as secondary endpoints. RESULTS: In Phase 1, there was a significantly higher median pain score (p < 0.001) and more episodes with unacceptable pain scores (46%) in the IV-PCA group compared with either epidural modality (6-14%; p < 0.001). In Phase 2, we observed a greater median pain score (p = 0.007) and higher proportion of patient episodes with unacceptable pain scores (38%) in the CEI group compared with both the IV-PCA (13%) and PIEB-PCEA (14%) groups (p = 0.001). There was a significant difference in median OMED used throughout all phases across the PIEB-PCEA (0 mg), IV-PCA (70 mg), and CEI (15 mg) groups (p < 0.001). CONCLUSIONS: PIEB-PCEA is safe and offers superior analgesia compared to IV-PCA or CEI for pain control after applicator placement in cervical brachytherapy.

Surgery at specialised sarcoma centres improves patient outcomes - A systematic review by the Australia and New Zealand sarcoma association clinical practice guidelines working party.

BACKGROUND: Optimal management of sarcoma requires multidisciplinary team input throughout the process of diagnosis, treatment and follow up. This systematic review aimed to evaluate the impact of surgery performed at specialised sarcoma centres on outcomes. METHODS: A systematic review was conducted using the population, intervention, comparison and outcome (PICO) model. Medline, Embase, Cochrane Central databases were queried for publications that evaluated the local control, limb salvage rate, 30-day and 90-day surgical mortality, and overall survival in patients undergoing surgery in a specialist sarcoma centre compared with non-specialist centre. Each study was screened by two independent reviewers for suitability. A qualitative synthesis of the results was performed. RESULTS: Sixty-six studies were identified. The majority of studies were Level III-3 as assessed by the NHMRC Evidence Hierarchy, whilst just over half of the studies were of good quality. Definitive surgery performed at specialised sarcoma centres was associated with improved local control as defined by lower rate of local relapse, higher rate of negative surgical margins, improved local recurrence free survival and higher limb conservation rate. Available evidences show a favourable pattern of lower 30-day and 90-day mortality rates, and greater overall survival when surgery was performed in specialist sarcoma centres compared with non-specialised centres. CONCLUSIONS: Evidences support better oncological outcomes when surgery is performed at specialised sarcoma centre. Patients with suspected sarcoma should be referred early to a specialised sarcoma centre for multidisciplinary management, which includes planned biopsy and definitive surgery.

Kindling in humans: Does secondary epileptogenesis occur?

The relevance of secondary epileptogenesis for human epilepsy remains a controversial subject decades after it was first described in animal models. Whether or not a previously normal brain region can become independently epileptogenic through a kindling-like process has not, and cannot, be definitely proven in humans. Rather than reliance on direct experimental evidence, attempts to answering this question must depend on observational data. In this review, observations based largely upon contemporary surgical series will advance the case for secondary epileptogenesis in humans. As will be argued, hypothalamic hamartoma-related epilepsy provides the strongest case for this process; all the stages of secondary epileptogenesis can be observed. Hippocampal sclerosis (HS) is another pathology where the question of secondary epileptogenesis frequently arises, and observations from bitemporal and dual pathology series are explored. The verdict here is far more difficult to reach, in large part because of the scarcity of longitudinal cohorts; moreover, recent experimental data have challenged the claim that HS is acquired consequent to recurrent seizures. Synaptic plasticity more than seizure-induced neuronal injury is the likely mechanism of secondary epileptogenesis. Postoperative running-down phenomenon provides the best evidence that a kindling-like process occurs in some patients, evidenced by its reversal. Finally, a network perspective of secondary epileptogenesis is considered, as well as the possible role for subcortical surgical interventions.

Can the Oral Bioavailability of the Discontinued Prostate Cancer Drug Galeterone Be Improved by Processing Method? KinetiSol® Outperforms Spray Drying in a Head-to-head Comparison.

Galeterone, a novel prostate cancer candidate treatment, was discontinued after a Phase III clinical trial due to lack of efficacy. Galeterone is weakly basic and exhibits low solubility in biorelevant media (i.e., ~ 2 µg/mL in fasted simulated intestinal fluid). It was formulated as a 50-50 (w/w) galeterone-hypromellose acetate succinate spray-dried dispersion to increase its bioavailability. Despite this increase, the bioavailability of this formulation may have been insufficient and contributed to its clinical failure. We hypothesized that reformulating galeterone as an amorphous solid dispersion by KinetiSol® compounding could increase its bioavailability. In this study, we examined the effects of composition and manufacturing technology (Kinetisol and spray drying) on the performance of galeterone amorphous solid dispersions. KinetiSol compounding was utilized to create galeterone amorphous solid dispersions containing the complexing agent hydroxypropyl-ß-cyclodextrin or hypromellose acetate succinate with lower drug loads that both achieved a ~ 6 × increase in dissolution performance versus the 50-50 spray-dried dispersion. When compared to a spray-dried dispersion with an equivalent drug load, the KinetiSol amorphous solid dispersions formulations exhibited ~ 2 × exposure in an in vivo rat study. Acid-base surface energy analysis showed that the equivalent composition of the KinetiSol amorphous solid dispersion formulation better protected the weakly basic galeterone from premature dissolution in acidic media and thereby reduced precipitation, inhibited recrystallization, and extended the extent of supersaturation during transit into neutral intestinal media.

The Effect of Luminance on Depth Perception in Augmented Reality Guided Laparoscopic Surgery.

Depth perception is a major issue in surgical augmented reality (AR) with limited research conducted in this scientific area. This study establishes a relationship between luminance and depth perception. This can be used to improve visualisation design for AR overlay in laparoscopic surgery, providing surgeons a more accurate perception of the anatomy intraoperatively. Two experiments were conducted to determine this relationship. First, an online study with 59 participants from the general public, and second, an in-person study with 10 surgeons as participants. We developed 2 open-source software tools utilising SciKit-Surgery libraries to enable these studies and any future research. Our findings demonstrate that the higher the relative luminance, the closer a structure is perceived to the operating camera. Furthermore, the higher the luminance contrast between the two structures, the higher the depth distance perceived. The quantitative results from both experiments are in agreement, indicating that online recruitment of the general public can be helpful in similar studies. An observation made by the surgeons from the in-person study was that the light source used in laparoscopic surgery plays a role in depth perception. This is due to its varying positioning and brightness which could affect the perception of the overlaid AR. We found that luminance directly correlates with depth perception for both surgeons and the general public, regardless of other depth cues. Future research may focus on comparing different colours used in surgical AR and using a mock operating room (OR) with varying light sources and positions.

Evaluation of a calibration rig for stereo laparoscopes.

BACKGROUND: Accurate camera and hand-eye calibration are essential to ensure high-quality results in image-guided surgery applications. The process must also be able to be undertaken by a nonexpert user in a surgical setting. PURPOSE: This work seeks to identify a suitable method for tracked stereo laparoscope calibration within theater. METHODS: A custom calibration rig, to enable rapid calibration in a surgical setting, was designed. The rig was compared against freehand calibration. Stereo reprojection, stereo reconstruction, tracked stereo reprojection, and tracked stereo reconstruction error metrics were used to evaluate calibration quality. RESULTS: Use of the calibration rig reduced mean errors: reprojection (1.47 mm [SD 0.13] vs. 3.14 mm [SD 2.11], p-value 1e-8), reconstruction (1.37 px [SD 0.10] vs. 10.10 px [SD 4.54], p-value 6e-7), and tracked reconstruction (1.38 mm [SD 0.10] vs. 12.64 mm [SD 4.34], p-value 1e-6) compared with freehand calibration. The use of a ChArUco pattern yielded slightly lower reprojection errors, while a dot grid produced lower reconstruction errors and was more robust under strong global illumination. CONCLUSION: The use of the calibration rig results in a statistically significant decrease in calibration error metrics, versus freehand calibration, and represents the preferred approach for use in the operating theater.

Safety and efficacy of bihemispheric sampling via transmidline stereoelectroencephalography.

OBJECTIVE: Stereoelectroencephalography (SEEG) is designed to target distributed cortical networks responsible for electroclinical seizure syndrome and to enable localization of the site of seizure onset in patients with intractable epilepsy. When the preimplantation hypothesis invokes the bilateral mesial frontal lobes, sampling of several deep-seated cortical sites in both hemispheres is required. In this study, the authors have demonstrated the feasibility of sampling bihemispheric areas with intentional implantation of an SEEG electrode crossing the midline (SECM) for sampling the cortex on both sides of the interhemispheric fissure. METHODS: An analysis of 231 consecutive SEEG procedures over 8 years was used to identify instances of bihemispheric sampling by using the transmidline SEEG technique. RESULTS: The authors identified 53 SEEG cases, with a total of 126 electrodes that crossed the interhemispheric fissure; all were in the frontal lobes. Eighty-three electrodes targeted the cingulate gyrus (18 rostral, 43 anterior, and 22 middle), 31 targeted the posterior orbitofrontal region, 8 sampled the medial prefrontal cortex, and 4 targeted nodular heterotopia around the frontal horns. The ictal onset zone was localized to the frontal lobe in 16 cases. SECM isolated interictal and ictal activity in the contralateral hemisphere in 6 cases and independent bihemispheric seizure activity in 2 cases. No hemorrhagic or infectious complications were noted in any of these cases. CONCLUSIONS: Based on this extensive experience of bihemispheric sampling, the authors concluded that this technique is safe and effective. In this series, SECM showed contralateral interictal and/or ictal epileptiform activity in 8 (15%) cases, and 9 (16%) cases (with unilateral implantation) had sufficient data to discard contralateral involvement, contributing to support of the epileptogenic network. SECM may reduce the number of electrodes used to sample bilateral mesial frontal or orbitofrontal cortices, and such an approach may lower the risk of hemorrhage and costs.

Long term outcomes of gastric mucosa-associated lymphoid tissue lymphoma treated with radiotherapy: A multi-center retrospective cohort study.

Gastric mucosa-associated lymphoid tissue (MALT) lymphoma is a rare disease. Radiotherapy remains an important definitive modality. We assessed the long term outcomes of patients with early stage gastric MALT marginal zone lymphoma (MZL) treated with definitive radiotherapy at three institutions in New South Wales, Australia. A retrospective, multi-center study of patients with gastric MALT MZ lymphoma treated with radiotherapy between 1st of March 1999 and 31st of May 2020 was conducted. Eligible patients were: age ≥18 years, treated with curative-intent radiotherapy, pathological diagnosis of MALT MZ lymphoma. There were 33 eligible patients. Complete response (CR) was reported in 30/31 (96.7%) of endoscopically assessed cases. During median follow up of 66.2 months (IQR 22-119 months), estimated 5 and 10 years local relapse free survival were 92.6% (95% CI: 83-100) and 92.6% (95% CI: 83-100); distant relapse free survival 95.8% (95% CI 88.2-100) and 64.7% (95% CI 43.4-96.4); freedom from treatment failure 92.6% (95% CI; 83.1-100) and 62.5% (95% CI; 41.7-93.7), respectively. There were six documented recurrences; one local, four distant, and both in one patient; two cases were high grade recurrences. 5 and 10 years OS were 92.4% and 73.5% respectively. There were no grade 3-5 late toxicities or treatment related deaths. Patients with gastric MALT MZL treated with definitive radiotherapy have excellent outcomes. In long term follow up a significant proportion developed distant low grade disease. Extended follow up should be considered in these patients. Treatment is well tolerated with minimal toxicity. Radiotherapy remains an important modality in the treatment of gastric MALT MZ lymphoma.

A randomized controlled trial of an enhanced recovery after surgery protocol in patients undergoing laparoscopic sleeve gastrectomy.

BACKGROUND: The purpose of this study was to evaluate the effect of an enhanced recovery after surgery (ERAS) protocol on opioid and anti-emetic use, length of stay and safety after laparoscopic sleeve gastrectomy (LSG). METHODS: Patients who underwent LSG between March 2018 and January 2019 at our accredited, high-volume bariatric surgery center were randomized to either standard of care (SOC) or ERAS. ERAS included a pre- and post-surgical medication regimen designed to reduce postoperative nausea, vomiting and pain. Outcomes included post-operative symptom scores, opioid use, anti-emetic use, time to achieve readiness for discharge (RFD) and inpatient and 30-day adverse events, readmissions and emergency department visits. RESULTS: The final analysis included 130 patients, (SOC 65; ERAS 65). Groups did not differ on demographics or comorbidities. Relative to SOC, fewer ERAS patients utilized opioids in the hospital ward (72.3% vs. 95.4%; p < .001), peak pain scores were significantly lower, and median time to achieve RFD was shorter (28.0 h vs. 44.4 h; p = 0.001). More ERAS patients were discharged on post-operative day 1 (38.5% vs. 15.4%; p < .05). The overall use of rescue anti-emetic medications was not different between groups. Rates of postoperative 30-day events, readmissions, and emergency department visits did not differ between groups. CONCLUSION: Relative to SOC, ERAS was associated with earlier discharge, lower pain scores, less frequent use of opioids and use in lower amounts after LSG with no differences in 30 day safety outcomes.

Chemoradiotherapy with concurrent durvalumab for the palliative treatment of oligometastatic oesophageal and gastrooesophageal carcinoma with dysphagia: a single arm phase II clinical trial (PALEO, sponsored by the Australasian Gastro-Intestinal Trials Group).

BACKGROUND: Oesophageal and gastrooesophageal junction (GOJ) carcinoma frequently present with dysphagia and de novo metastatic disease. There is scope to improve treatment paradigms to both address symptoms and improve survival. One method is integrating immune checkpoint inhibition with novel treatment combinations. METHODS: PALEO is a single arm, phase II clinical trial in patients with previously untreated, oligometastatic or locoregionally advanced oesophageal or GOJ carcinoma and dysphagia. PALEO is sponsored by the Australasian Gastro-Intestinal Trials Group (AGITG). Participants receive 2 weeks of therapy with concurrent hypofractionated radiotherapy of 30Gy in 10 fractions to the primary tumour, weekly carboplatin AUC2, weekly paclitaxel 50 mg/m2 and durvalumab 1500 mg q4 weekly, followed by durvalumab monotherapy continuing at 1500 mg q4weekly until disease progression, unacceptable toxicity or 24 months of therapy. A single metastasis is treated with stereotactic radiotherapy of 24Gy in 3 fractions in week 7. The trial primary endpoint is the progression free survival rate at 6 months. Secondary endpoints include duration of dysphagia relief, nutritional status change, quality of life, response rate, toxicity, progression free survival and overall survival. The tertiary endpoint is prediction of outcome based on biomarkers identified from patient serial blood samples collected pre- and post-radiotherapy. DISCUSSION: This unique investigator-initiated clinical trial is designed to simultaneously address the clinically relevant problems of dysphagia and distant disease control. The overarching aims are to improve patient nutrition, quality of life and survival with low toxicity therapy. AGITG PALEO is a multidisciplinary collaboration and will add to the understanding of the relationship between radiotherapy and the anti-tumour immune response. TRIAL REGISTRATION: Australian and New Zealand Clinical Trials Registry: ACTRN12619001371189 , registered 8 October 2019.

The benefit for radiotherapy at specialised sarcoma centres: A systematic review and clinical practice guidelines from the Australia and New Zealand Sarcoma Association.

Patients with sarcoma are best managed at specialised sarcoma centres as supported by published literature. Optimal management requires multidisciplinary team input to formulate the diagnosis and treatment sequencing taking into consideration multiple clinical and pathologic factors. This systematic review aimed to evaluate the impact on outcomes of radiotherapy at specialised sarcoma centres. A systematic review was conducted using the population, intervention, comparison and outcome model. A literature search was performed using Medline, Embase, Cochrane Central databases for publications from 1990 to February 2022 that evaluated the local control, survival and toxicity of radiotherapy at specialised sarcoma centres. A total of 21 studies were included (17 cancer registry studies, four retrospective comparative studies). Four studies reported the local recurrence endpoint when radiotherapy was part of limb conservation treatment and showed better conformity to clinical practice guidelines and an improved local recurrence free rate when radiotherapy treatment is supported through, but may not be necessarily delivered at a specialised sarcoma centres. Only one retrospective study analysed toxicity specifically and demonstrated that patients who received preoperative radiotherapy at community centres compared to radiotherapy at a specialised sarcoma centre were more likely to develop a major wound complication. Fourteen studies reported overall survival, and 12 of these showed significantly better 5-year overall survival for patients managed at specialised sarcoma centres, however the specific impact of radiotherapy delivered at sarcoma centres could not be determined. In conclusion, patients with sarcoma should be managed through specialised sarcoma centres for better oncological outcomes. Radiotherapy in specialised sarcoma centre is associated with a lower rate of wound complications and may contribute to improved oncological outcomes as part of the limb conservation treatment at a specialised sarcoma centre.

A comparative assessment of neutropenia events, healthcare resource use, and costs among cancer patients treated with lipegfilgrastim compared with pegfilgrastim in Germany.

PURPOSE: We assessed the occurrence of neutropenia and febrile neutropenia (FN) and the associated healthcare resource in cancer patients receiving myelosuppressive chemotherapy in combination with pegfilgrastim versus lipegfilgrastim. METHODS: This is a retrospective analysis using a German health insurance claims database. Adults receiving chemotherapy with a prescription code for pegfilgrastim (n = 734) or lipegfilgrastim (n = 346) were observed over a 1-year follow-up period. Patient subgroups were analyzed according to cancer type and FN risk. FN risk was based on the chemotherapy regimen and any additional neutropenia risk factors. Outcomes were adjusted via regression analysis. RESULTS: Most patients were classified as high FN risk (70.0% pegfilgrastim; 65.6% lipegfilgrastim cohort). The mean age was 58.2 years in the pegfilgrastim cohort and 58.0 years in the lipegfilgrastim cohort, with more female patients than male patients (77.3% vs 79.8%, respectively), and the majority had breast cancer (64.9% and 68.8%, respectively). Overall, 10.0% and 10.4% of patients receiving pegfilgrastim or lipegfilgrastim experienced a neutropenia event (p = 0.82), with 4.4% and 3.5% of patients experiencing a FN event (p = 0.49). The mean neutropenia event-related healthcare costs were €604 and €441 for the pegfilgrastim and lipegfilgrastim cohorts; among patients with lymphoma, these costs were significantly greater (p = 0.03) with pegfilgrastim (€1,612) versus lipegfilgrastim (€382). The mean all-cause hospitalizations were significantly (p < 0.01) higher for lymphoma patients receiving pegfilgrastim (2.76) versus lipegfilgrastim (1.60). CONCLUSION: Overall, patients treated with pegfilgrastim and lipegfilgrastim were comparable in terms of neutropenia occurrences in the 1-year follow-up. In patients with lymphoma, neutropenia event-related healthcare costs and all-cause hospitalizations were significantly higher with pegfilgrastim compared with lipegfilgrastim in this study; however, this should be interpreted with caution in light of the limited sample size and the absence of clinical information.

Population-level utilisation of neoadjuvant radiotherapy for the treatment of rectal cancer.

PURPOSE: International clinical guidelines recommend long- or short-course neoadjuvant radiotherapy for locally advanced rectal cancer. This study aims to examine variation in the use of neoadjuvant radiotherapy for rectal cancer and identify patient and hospital factors that underpin this variation. METHODS AND MATERIALS: We conducted a retrospective, consecutive cohort study using statewide hospitalisation and radiotherapy data from New South Wales, Australia, 2013-2018. Included participants had a primary rectal adenocarcinoma and underwent surgical resection. Factors associated with the use or not of any neoadjuvant radiotherapy, and short versus long-course were explored using multilevel logistic regression models. RESULTS: Of the 2912 people included in the study, 43% received neoadjuvant radiotherapy. There was significant variation in the use of neoadjuvant radiotherapy depending on geographic location. Abdominoperineal excision (odds ratio [OR] = 1.87, 95% confidence interval [CI] = 1.53-2.28) and having surgery in a public hospital (OR = 2.34, 95% CI = 1.92-2.87) were both predictors of use. Among those receiving neoadjuvant radiotherapy, 17% received short-course therapy, with short-course declining over the study period. CONCLUSIONS: The use of neoadjuvant radiotherapy for rectal cancer is highly variable, with differences only partially explained by assessable patient-or hospital-level factors. Understanding neoadjuvant radiotherapy utilisation patterns may assist in identifying barriers and opportunities to improve adherence to clinical guidelines.

Systemic treatments and outcomes in CIC-rearranged Sarcoma: A national multi-centre clinicopathological series and literature review.

CIC-rearranged sarcoma is a recently established, ultra-rare, molecularly defined sarcoma subtype. We aimed to further characterise clinical features of CIC-rearranged sarcomas and explore clinical management including systemic treatments and outcomes. METHODS: A multi-centre retrospective cohort study of patients diagnosed between 2014-2019. RESULTS: Eighteen patients were identified. The median age was 27 years (range 13-56), 10 patients were male (56%), 11 patients (61%) had localised disease and 7 patients had advanced (metastatic or unresectable) disease at diagnosis. Of 11 patients with localised disease at diagnosis, median overall survival (OS) was 40.6 months and the 1-, 2- and 5-year OS estimates were 82%, 64% and 34% respectively. Nine patients (82%) underwent surgery (all had R0 resections), 8 (73%) patients received radiotherapy to the primary site (median dose 57Gy in 28 fractions), and 8 (73%) patients received chemotherapy (predominantly Ewing-based regimens). Metastases developed in 55% with a median time to recurrence of 10.5 months. In patients with advanced disease at diagnosis, median OS was 12.6 months (95% CI 5.1-20.1), 1-year OS was 57%. Median progression-free survival was 5.8 months (95% CI 4.5-7.2). Durable systemic therapy responses occurred infrequently with a median duration of systemic treatment response of 2.1 months. One durable complete response of metastatic disease to VDC/IE chemotherapy was seen. Responses to pazopanib (n = 1) and pembrolizumab (n = 1) were not seen. CONCLUSION: In this series, CIC-rearranged sarcomas affected young adults and had a high incidence of presenting with, or developing, metastatic disease. The prognosis overall was poor. In advanced disease, durable systemic therapy responses were infrequent.

Automatic, global registration in laparoscopic liver surgery.

PURPOSE: The initial registration of a 3D pre-operative CT model to a 2D laparoscopic video image in augmented reality systems for liver surgery needs to be fast, intuitive to perform and with minimal interruptions to the surgical intervention. Several recent methods have focussed on using easily recognisable landmarks across modalities. However, these methods still need manual annotation or manual alignment. We propose a novel, fully automatic pipeline for 3D-2D global registration in laparoscopic liver interventions. METHODS: Firstly, we train a fully convolutional network for the semantic detection of liver contours in laparoscopic images. Secondly, we propose a novel contour-based global registration algorithm to estimate the camera pose without any manual input during surgery. The contours used are the anterior ridge and the silhouette of the liver. RESULTS: We show excellent generalisation of the semantic contour detection on test data from 8 clinical cases. In quantitative experiments, the proposed contour-based registration can successfully estimate a global alignment with as little as 30% of the liver surface, a visibility ratio which is characteristic of laparoscopic interventions. Moreover, the proposed pipeline showed very promising results in clinical data from 5 laparoscopic interventions. CONCLUSIONS: Our proposed automatic global registration could make augmented reality systems more intuitive and usable for surgeons and easier to translate to operating rooms. Yet, as the liver is deformed significantly during surgery, it will be very beneficial to incorporate deformation into our method for more accurate registration.