Participant Evaluation of a Multi-disciplinary Oncology Preceptorship Training Program for Oncology Health Professionals from Kumasi, Ghana

A critical shortage of skilled healthcare workers is a primary cause of disparate global cancer outcomes. We report participant evaluation of a multidisciplinary preceptorship program. In collaboration with the city of Kumasi, Ghana, Mayo Clinic and the City Cancer Challenge hosted a preceptorship program for comprehensive multidisciplinary breast and cervix cancer training. A total of 14 healthcare workers from Kumasi received two weeks of training at Mayo Clinic in November and December 2021. Each participant and preceptor were requested to complete an anonymous post-participation survey. Of the 14 trainee participants, 10 (71%) completed the survey. All respondents found the program "valuable and applicable to their clinical practice." Ninety percent reported they were able to "review effective and critical elements in the development and expansion of the multidisciplinary team" and able to "solve practical clinical cases as a team". General themes of satisfaction included: (1) organization and administration, (2) clinical observations and demonstrations, (3) guidelines development, and (4) recognizing the central importance of cultivating a team-based approach. Of the 40 preceptors, 16 (40%) completed the survey. All respondents reported they felt the training would meaningfully "influence patient care in Ghana", that participation "added value or joy to their clinical practice," and all wished to "participate in future preceptorship programs". After a focused two-week program, trainees reported high satisfaction, usefulness from observing specialized cancer care, and value in closely observing a multidisciplinary oncology team. Preceptors reported the experience added joy and perspective to their clinical practice and wished to participate in future programs.

Gastroblastoma of the Pylorus: A Case Report and Review of the Literature

Gastroblastoma is an extremely rare biphasic tumor that typically occurs in the stomach in patients between the ages of 10 and 30. Only 16 cases have been reported previously. These tumors are important to diagnose and distinguish from more aggressive neoplasms; although numbers are small, prognosis appears excellent overall with complete excision, with only occasional metastasis and/or local recurrence. We report a case of gastroblastoma in a 26-year-old male arising from the pylorus and extending through the first and second portions of the duodenum. This is the first case to be reported from this specific location.

Interactive enhancer hubs (iHUBs) mediate transcriptional reprogramming and adaptive resistance in pancreatic cancer

OBJECTIVE

Pancreatic ductal adenocarcinoma (PDAC) displays a remarkable propensity towards therapy resistance. However, molecular epigenetic and transcriptional mechanisms enabling this are poorly understood. In this study, we aimed to identify novel mechanistic approaches to overcome or prevent resistance in PDAC.

DESIGN

We used in vitro and in vivo models of resistant PDAC and integrated epigenomic, transcriptomic, nascent RNA and chromatin topology data. We identified a JunD-driven subgroup of enhancers, called interactive hubs (iHUBs), which mediate transcriptional reprogramming and chemoresistance in PDAC.

RESULTS

iHUBs display characteristics typical for active enhancers (H3K27ac enrichment) in both therapy sensitive and resistant states but exhibit increased interactions and production of enhancer RNA (eRNA) in the resistant state. Notably, deletion of individual iHUBs was sufficient to decrease transcription of target genes and sensitise resistant cells to chemotherapy. Overlapping motif analysis and transcriptional profiling identified the activator protein 1 (AP1) transcription factor JunD as a master transcription factor of these enhancers. JunD depletion decreased iHUB interaction frequency and transcription of target genes. Moreover, targeting either eRNA production or signaling pathways upstream of iHUB activation using clinically tested small molecule inhibitors decreased eRNA production and interaction frequency, and restored chemotherapy responsiveness in vitro and in vivo. Representative iHUB target genes were found to be more expressed in patients with poor response to chemotherapy compared with responsive patients.

CONCLUSION

Our findings identify an important role for a subgroup of highly connected enhancers (iHUBs) in regulating chemotherapy response and demonstrate targetability in sensitisation to chemotherapy.

Abstract 1944: Prognostic biomarkers for gallbladder cancer: A machine learning approach

Gallbladder cancer (GBC) is one of the deadliest cancers, with a 5-year-survival-rate of less than 5 percent for late-stage disease. The response rate to chemotherapy among GBC patients is generally poor. Recent research has attempted to identify diagnostic, prognostic, and predictive biomarkers, however, currently, no biomarkers can accurately diagnose GBC and predict patients’ prognosis. Integrative analysis of molecular and clinical characterization has not been fully established, and minimal improvement has been made to the survival of these patients, in part due to the heterogeneity of GBC. Machine learning techniques have been proven to empower analysis of big data in oncology, allowing for improvement in the generation of biomarkers to predict patient outcomes. Using machine learning, we can utilize high-throughput RNA sequencing with clinicopathologic data to develop a predictive tool for GBC prognosis. Current predictive models for GBC outcomes often utilize clinical data only, with the highest C-statistic reported being 0.71. C-statistic values over 0.7 generally indicate good models, however 0.8 is the threshold for strong predictive models. We aim to build a superior algorithm to predict overall survival in GBC patients with advanced disease, using machine learning approaches to prioritize biomarkers for GBC prognosis. We have identified over 80 fresh frozen GBC tissue samples from Mayo Clinic Rochester, Dongsan Medical Center in Daegu, Korea, University of the Witwatersrand, in Johannesburg, South Africa, Lithuanian University of Health Science in Vilnius, Lithuania, and University of Calgary in Calgary, Canada, from patients enrolled between 2012 and 2021. We will perform next-generation RNA sequencing on these tissue samples. The patients’ clinical, pathologic and survival data will be abstracted from the medical record uniformly across sites. Feature engineering and dimensionality reduction will be performed. Then random forests, support vector machines, and gradient boosting machines will be applied to train the data. Variable importance will prioritize multi-omic markers. Standard 5-fold cross validation will be used to assess performance of each ML algorithm. If overall survival can be better predicted with the addition patients’ transcriptional sequencing data compared to using clinical profiles alone, we can gain a greater understanding of key biomarkers driving the tumor phenotype.

Citation Format: Linsey Jackson, Loretta Allotey, Valles Kenneth, Gavin Oliver, Asha Nair, Daniel O'Brien, Rondell Graham, Mitesh Borad, Arjun Athreya, Lewis Roberts. Prognostic biomarkers for gallbladder cancer: A machine learning approach [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1944.

First branchial arch cyst in an elderly patient: diagnostic dilemma and subsequent management

The branchial system plays a significant role in the embryological development of the many internal and external human body structures. Failure of normal development of these systems may result in branchial system anomalies. Anomalies of the first branchial cleft are rare and account for 1-8% of all branchial anomalies. They have an incidence of 1 per 1 million births, most of which are diagnosed in early childhood. We present an unusual case of a first branchial arch cyst in an elderly gentleman: a 65-year-old man who presented with a persistent swelling in the left pre-auricular region with no associated sinus, fistulae or lymphadenopathy and with an intact facial nerve. Investigations including fine needle aspiration, ultrasound and magnetic resonance imaging led to the diagnosis of a lesion of salivary origin and an extracapsular dissection was undertaken. The histological appearance on excision was, however, in keeping with a first arch branchial cyst. In conclusion, the nonspecific clinical and radiological presentation of first branchial arch anomalies may lead to difficulty and often delay in the diagnosis of these lesions, particularly in elderly patients as it is more often associated with childhood and adolescence. A high level of suspicion is mandatory to prevent inappropriate management in the form of incision and drainage, which further increases the risk of recurrence and facial nerve injury at the time of formal excision due to scarring.

First branchial arch cyst in an elderly patient: diagnostic dilemma and subsequent management

The branchial system plays a significant role in the embryological development of the many internal and external human body structures. Failure of normal development of these systems may result in branchial system anomalies. Anomalies of the first branchial cleft are rare and account for 1-8% of all branchial anomalies. They have an incidence of 1 per 1 million births, most of which are diagnosed in early childhood. We present an unusual case of a first branchial arch cyst in an elderly gentleman: a 65-year-old man who presented with a persistent swelling in the left pre-auricular region with no associated sinus, fistulae or lymphadenopathy and with an intact facial nerve. Investigations including fine needle aspiration, ultrasound and magnetic resonance imaging led to the diagnosis of a lesion of salivary origin and an extracapsular dissection was undertaken. The histological appearance on excision was, however, in keeping with a first arch branchial cyst. In conclusion, the nonspecific clinical and radiological presentation of first branchial arch anomalies may lead to difficulty and often delay in the diagnosis of these lesions, particularly in elderly patients as it is more often associated with childhood and adolescence. A high level of suspicion is mandatory to prevent inappropriate management in the form of incision and drainage, which further increases the risk of recurrence and facial nerve injury at the time of formal excision due to scarring.

Liver transplantation for acute liver failure in a SARS-CoV-2 PCR-positive patient

Current guidelines recommend deferring liver transplantation (LT) in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection until clinical improvement occurs and two PCR tests collected at least 24 hours apart are negative. We report a case of an 18-year-old, previously healthy African-American woman diagnosed with COVID-19, who presents with acute liver failure (ALF) requiring urgent LT in the context of SARS-CoV-2 polymerase chain reaction (PCR) positivity. The patient was thought to have acute Wilsonian crisis on the basis of hemolytic anemia, alkaline phosphatase:bilirubin ratio <4, AST:ALT ratio >2.2, elevated serum copper, and low uric acid, although an unusual presentation of COVID-19 causing ALF could not be excluded. After meeting criteria for status 1a listing, the patient underwent successful LT, despite ongoing SARS-CoV-2 PCR positivity. Remdesivir was given immediately posttransplant, and mycophenolate mofetil was withheld initially and the SARS-CoV-2 PCR test eventually became negative. Three months following transplantation, the patient has made a near-complete recovery. This case highlights that COVID-19 with SARS-CoV-2 PCR positivity may not be an absolute contraindication for transplantation in ALF. Criteria for patient selection and timing of LT amid the COVID-19 pandemic need to be validated in future studies.

Colonic adenocarcinoma resulting in recurrent colic and hematochezia in an Arabian stallion

A fourteen-year-old Arabian stallion was presented with general weakness and hematochezia. Clinical examination showed tachycardia but the rest of the physical parameters were within normal limits. Transcutaneous abdominal ultrasonography showed distended small intestinal loops with normal motility but increased mural thickness. Gastroscopic examination revealed small focal lesions in the non-glandular part of the stomach around the margo plicatus of the greater curvature, with a score of II/IV Equine Gastric Ulcer Syndrome. Blood analysis revealed anemia, hypoproteinemia and neutrophilia. Treatment was palliative and was determined based on the initial findings. Despite intensive medical treatment, the horse was euthanized due to progressive deterioration of its condition. Post-mortem necropsy and histopathology revealed an adenocarcinoma with osseous metaplasia within the left dorsal colon.

High prevalence of hepatic steatosis and vascular thrombosis in COVID-19: A systematic review and meta-analysis of autopsy data

BACKGROUND

Coronavirus disease 2019 (COVID-19) disease can frequently affect the liver. Data on hepatic histopathological findings in COVID-19 is scarce.

AIM

To characterize hepatic pathological findings in patients with COVID-19.

METHODS

We conducted a systematic review with meta-analysis registered on PROSPERO (CRD42020192813), following PRISMA guidelines. Eligible trials were those including patients of any age and COVID-19 diagnosis based on a molecular test. Histopathological reports from deceased COVID-19 patients undergoing autopsy or liver biopsy were reviewed. Articles including less than ten patients were excluded. Proportions were pooled using random-effects models. Q statistic and I² were used to assess heterogeneity and levels of evidence, respectively.

RESULTS

We identified 18 studies from 7 countries; all were case reports and case series from autopsies. All the patients were over 15 years old, and 67.2% were male. We performed a meta-analysis of 5 studies, including 116 patients. Pooled prevalence estimates of liver histopathological findings were hepatic steatosis 55.1% [95% confidence interval (CI): 46.2-63.8], congestion of hepatic sinuses 34.7% (95%CI: 7.9-68.4), vascular thrombosis 29.4% (95%CI: 0.4-87.2), fibrosis 20.5% (95%CI: 0.6-57.9), Kupffer cell hyperplasia 13.5% (95%CI: 0.6-54.3), portal inflammation 13.2% (95%CI: 0.1-48.8), and lobular inflammation 11.6% (95%CI: 0.3-35.7). We also identified the presence of venous outflow obstruction, phlebosclerosis of the portal vein, herniated portal vein, periportal abnormal vessels, hemophagocytosis, and necrosis.

CONCLUSION

We found a high prevalence of hepatic steatosis and vascular thrombosis as major histological liver features. Other frequent findings included portal and lobular inflammation and Kupffer cell hyperplasia or proliferation. Further studies are needed to establish the mechanisms and implications of these findings.

Impact of COVID-19 on UK radiology training: a questionnaire study

AIM

To understand the impact of COVID-19 on radiology trainee experience and well-being.

MATERIALS AND METHODS

A questionnaire designed to capture the impact of COVID-19 on radiology training, working patterns, and well-being was sent to all speciality trainees in a regional UK radiology school. The survey was distributed at the beginning of May 2020 and responses collected over 2 weeks. Trainees were questioned about changes that had occurred over a time period starting at the beginning of the COVID-19 pandemic. All survey responses (n=29) were anonymised and the results were subsequently analysed.

RESULTS

Sixty-two percent (29 of 47) of trainees within the deanery, who were spread across seven different hospital sites, responded to the questionnaire. All trainees felt that overall radiology workload had decreased in response to COVID-19. Seventy-two percent (21/29) stated that their workload had significantly decreased. Seventy percent (19/27) reported decreased subspecialty experience, and 19% (5/27) reported a complete lack of subspecialty training. Twenty-four percent (7/29) of trainees were redeployed from radiology to clinical ward-based work. Forty-eight percent reported experiencing a worsening in their well-being compared to before the pandemic.

CONCLUSION

The first wave of the COVID-19 pandemic had a significant impact on training and well-being. Lessons learnt from this report should help prepare for a second-wave of COVID-19 or future pandemics.

Multi-observer concordance and accuracy of the British Thoracic Society scale and other visual assessment qualitative criteria for solid pulmonary nodule assessment using FDG PET-CT

AIM

To compare the interobserver reliability and diagnostic accuracy of the British Thoracic Society (BTS) scale and other visual assessment criteria in the context of 2-[¹⁸F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET)-computed tomography (CT) evaluation of solid pulmonary nodules (SPNs).

MATERIALS AND METHODS

Fifty patients who underwent FDG PET-CT for assessment of a SPN were identified. Seven reporters with varied experience at four centres graded FDG uptake visually using the British Thoracic Society (BTS) four-point scale. Five reporters also scored SPNs according to three- and five-point visual assessment scales and using semi-quantitative assessment (maximum standardised uptake value [SUV_max]). Interobserver reliability was assessed with the intra-class correlation coefficient (ICC) and weighted Cohen's kappa (κ). Diagnostic performance was evaluated by receiver operator characteristic (ROC) analysis.

RESULTS

Good interobserver reliability was demonstrated with the BTS scale (ICC=0.78, 95% confidence interval [CI]: 0.69-0.85) and five-point scale (ICC=0.78, 95 CI 0.68-0.86), whilst the three-point scale demonstrated moderate reliability (ICC=0.70, 95% CI: 0.59-0.80). Almost perfect agreement was achieved between two consultants (κ=0.85), and substantial agreement between two other consultants (κ=0.78) using the BTS scale. ROC curves for the BTS and five-point scales demonstrated equivalent accuracy (BTS area under the ROC curve [AUC]=0.768; five-point AUC=0.768). SUV_max was no more accurate compared to the BTS scale (SUV_max AUC=0.794; BTS AUC=0.768, p=0.43).

CONCLUSIONS

The BTS scale can be applied reliably by reporters with varied levels of PET-CT reporting experience, across different centres and has a diagnostic performance that is not surpassed by alternative scales.

THU0002 SOLVING THE COMPLEX MHC ASSOCIATIONS IN SLE IDENTIFIES SEX-RELATED GENE EFFECTS

Background:

Genome-wide association analyses reveal that the Major Histocompatibility Complex (MHC) is the site of the strongest association signals in SLE and Sjögren’s syndrome. This associations in lupus and Sjögren’s syndrome are linked toHLAalleles: HLA-DRB1*03:01 and HLA-DRB1*15:01 (in Europeans). The DRB1*03:01 allele resides on an extended MHC haplotype which includes loss of the complement C4A gene. Whether C4 makes a genetic contribution to SLE/Sjogren’s risk has been a long standing issue of contention1. In comparison, it has been shown that elevated copy number of C4 is a genetic risk factor for schizophrenia2.

Objectives:

To define the causal MHC genes in SLE/Sjogren’s accommodating both structural and highly polymorphic variation.

Methods:

Use NG sequencing data from across the MHC to generate a panel of variants that inform class III structural variation involving the candidate genes coding complementC4AandC4Bas described2. To further improve the resolution of the association using transancestral mapping approach in SLE: examining cohorts of European ancestry (from ImmunoChip) and data from the MHC region of an African-American GWAS in SLE.

Results:

Comparing European and African data, we have shown that the association signals in SLE can be best explained by signals arising from 1) copy number variation of the complement component 4 (C4) genes in the MHC locus (Fig. 1) and 2) by a shared region in the class II region on the HLA-DRB1*15:01 (in Europeans) and HLA-DRB1*15:03 (in Africans) that likely operates to elevated HLA class II gene expression (Fig. 2). TheC4locus generates a 7-fold variation in risk for lupus (95% CI: 5.88-8.61;p<10-117in total) and 16-fold variation in risk for Sjögren’s syndrome (95% CI: 8.59-30.89;p<10-23in total), withC4Aprotecting more strongly thanC4Bin both illnesses. In schizophrenia, elevated C4 copy number elevates disease risk, whereas in SLE and Sjögren’s lower copy numbers ofC4genes correlate with higher disease risk. In all three illnesses,C4alleles acted more strongly in men than in women: common combinations ofC4AandC4Bgenerated 14-fold variation in risk for lupus and 31-fold variation in risk for Sjögren’s syndrome in men (versus 6-fold and 15-fold among women respectively) and affected schizophrenia risk about twice as strongly in men as in women. At a protein level, both C4 and its effector (C3) were present at greater levels in men than women in cerebrospinal fluid (p<10-5for both C4 and C3) and plasma among adults ages 20-50, corresponding to the ages of differential disease vulnerability. Sex differences in complement protein levels may help explain the larger effects ofC4alleles in men, women’s greater risk of SLE and Sjogren’s, and men’s greater vulnerability in schizophrenia.

Figure 1.

Loss ofC4is risk in African and European ancestry cohorts. A = C4A, B = C4B, A-B = C4A + C4B (L) = Long form (with HERV), (S) = short form

Figure 2.

Common class II association after removing C4 signal

Conclusion:

These results nominate the complement system as a source of sexual dimorphism in vulnerability to diverse illnesses.

References:

[1]Hanscombe KB, Morris DL, Noble JAet al. Hum Mol Genet. 2018; 27(21): 3813-3824.

[2]Sekar A, Bialas AR, de Rivera Het al. Nature.2016; 530(7589): 177-83.

Acknowledgments:

This work was supported by the National Human Genome Research Institute (HG006855), the National Institute of Mental Health (MH112491, MH105641, MH105653), and the Stanley Center for Psychiatric Research. The KCL/GSTT biomedical research centre.

Disclosure of Interests:

Nolan Kamitaki: None declared, Bob Handsaker: None declared, David Morris: None declared, Carl Langefeld: None declared, Robert Graham Employee of: Genentech, Speakers bureau: Genentech, Lindsey Criswell: None declared, Steve McCarroll: None declared, Tim Vyse: None declared

Multi-omic analysis of the effects of low frequency ventilation during cardiopulmonary bypass surgery

BACKGROUND

Heart surgery with cardio-pulmonary bypass (CPB) is associated with lung ischemia leading to injury and inflammation. It has been suggested this is a result of the lungs being kept deflated throughout the duration of CPB. Low frequency ventilation (LFV) during CPB has been proposed to reduce lung dysfunction.

METHODS

We used a semi-biased multi-omic approach to analyse lung biopsies taken before and after CPB from 37 patients undergoing coronary artery bypass surgery randomised to both lungs left collapsed or using LFV for the duration of CPB. We also examined inflammatory and oxidative stress markers from blood samples from the same patients.

RESULTS

30 genes were induced when the lungs were left collapsed and 80 by LFV. Post-surgery 26 genes were significantly higher in the LFV vs. lungs left collapsed, including genes associated with inflammation (e.g. IL6 and IL8) and hypoxia/ischemia (e.g. HIF1A, IER3 and FOS). Relatively few changes in protein levels were detected, perhaps reflecting the early time point or the importance of post-translational modifications. However, pathway analysis of proteomic data indicated that LFV was associated with increased "cellular component morphogenesis" and a decrease in "blood circulation". Lipidomic analysis did not identify any lipids significantly altered by either intervention.

DISCUSSION

Taken together these data indicate the keeping both lungs collapsed during CPB significantly induces lung damage, oxidative stress and inflammation. LFV during CPB increases these deleterious effects, potentially through prolonged surgery time, further decreasing blood flow to the lungs and enhancing hypoxia/ischemia.

Seasonal distribution and foraging occurrence of Cook Inlet beluga whales based on passive acoustic monitoring

A paucity of information on the basic biology and ecology of Cook Inlet beluga whales Delphinapterus leucas remains a decade after the species was listed as endangered in 2008. The causes of its continued decline remain unclear. This lack of knowledge limits our understanding of, and ability to manage, potential threats impeding the recovery of this endangered population. Seasonal distribution and foraging ecology, particularly during winter, are currently among the most basic gaps in knowledge. Therefore, we conducted a year-round passive acoustic monitoring program from 2008-2013, monitoring 13 locations within the belugas’ critical habitat. We identified seasonal occurrence patterns across years at most locations. Detections were higher in the upper inlet during summer, peaking in known concentration areas. The occurrence of whales in the upper inlet when ice coverage peaked during winter was more prevalent than previously suggested. We documented seasonal differences in foraging habitat preference, with foraging behavior more prevalent during summer, particularly near upper inlet rivers, than during winter. Foraging peaks coincided with the presence of different anadromous fish runs from spring to fall. Low levels of feeding activity in winter suggest a lack of feeding aggregation areas, feeding in non-monitored offshore waters, or increased effort on benthic prey. These results represent a substantial contribution to our knowledge of Cook Inlet beluga seasonal distribution and foraging ecology, which will strengthen conservation and management strategies and thus more effectively promote recovery of this endangered population.

Substrate Supporting Disc Method for Confirmed Detection of Total Coliforms and E. coli in all Foods: Collaborative Study

The Coli Complete® substrate supporting disc (SSD) method for simultaneous confirmed total coliform count and Escherichia coli determination in all foods was compared with AOAC most probable number (MPN) methods, 966.23 and 966.24. Twenty-nine laboratories participated in this collaborative study in which 6 food types were analyzed. Four food types, raw ground beef, pork sausage, raw liquid milk, and nut meats, were naturally contaminated with coliform bacteria. Two foods, dry egg and fresh frozen vegetables, were seeded with coliforms. Three food types, ground beef, raw liquid milk, and pork sausage, were naturally contaminated with E. coli. Although pork sausage was naturally contaminated, the level was very low (&lt;10/50 g); therefore, additional E. coli were inoculated into 1 lot of this food type. Three food types, nut meats, dry egg, and fresh frozen vegetables, were inoculated with E. coli. For naturally contaminated samples, duplicate determinations were made on 3 separate lots for each food type. For inoculated samples, low, medium, and high contamination levels plus uninoculated control samples were examined in duplicate. Data were analyzed separately for total coliform bacteria and for E. coli. Mean log MPN counts were determined by the SSD method and the appropriate AOAC MPN method. Results were then analyzed for repeatability, reproducibility, and mean log MPN statistical equivalence. Results were statistically equivalent for all total coliform levels in all food types except frozen vegetable and raw nut meat uninoculated control samples and 1 lot of pork sausage where the SSD method produced statistically significant greater numbers. For the E. coli determinations, results were statistically equivalent across all samples and all levels for each food type. The SSD method has been adopted first action by AOAC International for confirmed detection of total coliforms and E. coli in all foods.

A multicentre retrospective cohort study of ovarian germ cell tumours: Evidence for chemotherapy de-escalation and alignment of paediatric and adult practice

BACKGROUND

Adult guidelines recommend BEP (bleomycin, etoposide, cisplatin) for all ovarian germ cell tumours, causing debilitating toxicities in young patients who will survive long term. Paediatricians successfully reduce toxicities by using lower bleomycin doses and substituting carboplatin for cisplatin, while testicular and paediatric immature teratomas (ITs) are safely managed with surgery alone.

AIM

The aim was to determine whether reduced-toxicity treatment could rationally be extended to patients older than 18 years.

METHODS

Multicentre cohort study was carried out in four large UK cancer centres over 12 years.

RESULTS

One hundred thirty-eight patients were enrolled. Overall survival was 93%, and event-free survival (EFS) was 72%. Neoadjuvant/adjuvant chemotherapy (82% BEP) caused 27 potentially chronic toxicities, and one patient subsequently died from acute lymphoblastic leukaemia. There was no difference in histology, stage or grade in patients ≤/>18 years, and EFS was not different in these age groups (≤18:28% and >18:28%; log-rank P = 0.96). Histological subtype powerfully predicted EFS (log-rank P = 4.9 × 10-7). Neoadjuvant/adjuvant chemotherapy reduced future relapse/progression in dysgerminoma (n = 37, chemo:0% vs. no chemo:20%), yolk sac tumour (n = 23, 26.3% vs.75%) and mixed germ cell tumour (n = 32, 40%vs.70%) but not in IT (n = 42, 33% vs.15%). Additionally, we observed no radiological responses to chemotherapy in ITs, pathological IT grade did not predict EFS (univariate hazard ratio 0.82, 95% confidence interval: 0.57-1.19, P = 0.94) and there were no deaths in this subtype.

CONCLUSION

Survival was excellent but chemotherapy toxicities were severe, implying significant overtreatment. Our data support the extension of reduced-toxicity, paediatric regimens to adults. Our practice-changing findings that IT was chemotherapy resistant and pathological grade uninformative strongly endorse exclusive surgical management of ovarian ITs at all ages.

Ultrasound Shear Wave Elastography as a Measure of Porcine Hepatic Disease in Right Heart Dysfunction: A Pilot Study

Patients with congenital heart disease with a pressure-overloaded right ventricle can develop liver disease and would benefit from non-invasive diagnostic modalities such as ultrasound shear wave elastography (US SWE). We sought to investigate the ability of US SWE to measure dynamic changes in liver stiffness with an acute fluid bolus in an animal model. Three piglets underwent surgical intervention to create a pressure-overloaded right ventricle and, 12 wk later, underwent US SWE, both pre- and post-intravenous infusion of a saline bolus. Ultrasound measures of shear modulus, velocity and attenuation were taken to characterize hepatic mechanical properties. Liver stiffness exhibited a dynamic component that increased after fluid bolus, although not reaching statistical significance with our small sample size, and these changes were greater in more diseased livers. US SWE may provide a promising non-invasive method for assessing dynamic changes in hydration status and degree of liver disease.

Abstract P4-13-06: Does large volume displacement oncoplastic surgery still offer an advantage of a low positive margin rate using the new SSO/ASBrS/ASTRO margin guidelines?

Purpose

Breast conservation has become the mainstay of surgical management for early stage breast cancer. Large volume displacement oncoplastic surgery (LVOS) uses reconstructive mastopexy and breast reduction techniques to allow for larger oncologic resections while providing good aesthetic outcomes in a single operation. Oncoplastic surgery publications have recently increased by 220%, demonstrating the increasing popularity of this surgical technique, 2 and many of these studies have demonstrated excellent oncologic outcomes.4 To date, however, no study has used the most recent SSO/ASBrS/ASTRO surgical margin recommendations to assess oncoplastic surgery. 4 Recent SSO/ASBrS/ASTRO guidelines established no ink on tumor as an adequate margin for invasive breast cancer and at least 2mm as adequate margins for ductal carcinoma in situ. The purpose of this study was to investigate the surgical margin rates of LVOS using the new SSO/ASBrS/ASTRO guidelines. We presumed that under the newer, stricter guidelines, LVOS would have a higher positive margin rate than reported in the past literature.

Methods:

Our study consisted of two parts. First, a literature review to assess margin rates before the introduction of SSO/ASBrS/ASTRO guidelines was done using PRISMA guidelines with an international Pubmed search and reviewed by two blinded authors. The search included keywords such as “oncoplastic breast surgery,” “lumpectomy,” “partial mastectomy,” and “positive margins associated with breast surgery.” All articles either pertained to LVOS, standard lumpectomy (SL) or both. The inclusion criteria for our study included histology discrepancy, and new guideline margin status. From this, we determined the published positive margin for SL and LVOS. Second, we analyzed all LVOS performed at our institution since the adoption of the new SSO/ASBrS/ASTRO margin guidelines and compared these margin rates to the literature review outcomes using Z tests.

Results:

Our study consisted of 1702 patients. There were 847 patients in LVOS group and 855 patients in the SL group. Of the 45 papers evaluated, 34 were not included due to exclusion criteria (missing: new margin guidelines, histology, or margin status). The pre-guideline positive margin rate for LVOS was lower than with SL (12.51% vs. 20.4%, P-value &lt;0.001). Of the 50 LVOS operations done at our institution since adoption of the SSO/ASBrS/ASTRO margin guidelines, no statistical difference in the positive margin rates was noted when compared to the literature rates (10% vs. 12.67% respectively, P-value 0.5796). Positive margin rates for LVOS at our institution were lower than SL margin rates reported in the literature (P-value 0.0358).

Conclusions:

This study demonstrates that even with the stricter margin SSO/ASBrS/ASTRO guidelines, LVOS still has a low positive margin rate comparable to pre-guideline literature reports. LVOS continues to have a significantly lower positive margin rate than SL. This is the first study to report margin rates for LVOS after the adoption of the SSO/ASBrS/ASTRO guidelines, and confirms the importance of LVOS in providing optimal oncologic outcomes for patient with large locally advanced breast cancer.

Citation Format: Jonczyk MM, Patel K, Graham R, Naber S, Erban J, Chen L, Chatterjee A. Does large volume displacement oncoplastic surgery still offer an advantage of a low positive margin rate using the new SSO/ASBrS/ASTRO margin guidelines? [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 P4-13-06.

Frequent expression of fibroblast growth factor-23 (FGF23) mRNA in aneurysmal bone cysts and chondromyxoid fibromas

Osteomalacia has multiple aetiologies including the least common, tumour-induced osteomalacia (TIO). Recently, most cases of TIO have been confirmed to be due to phosphaturic mesenchymal tumour of mixed connective tissue type (PMTMCT). Most cases of TIO are the result of production of the fibroblast growth factor-23 (FGF-23) by the tumour. The authors recently showed reverse transcriptase PCR (RT-PCR) for FGF-23 to be valuable in the diagnosis of PMTMCT. However, the authors also noted FGF-23 expression in some cases of aneurysmal bone cyst (ABC) and chondromyxoid fibroma (CMF). For the present study, the authors studied FGF-23 expression by RT-PCR in 19 cases of ABC and eight cases of CMF, all with typical clinical and radiographic features and without evidence of TIO. Seven of 16 (44%) ABC and two of seven (29%) CMF were positive for FGF-23. These results confirm that ABC and CMF not uncommonly express FGF-23. These results strongly suggest caution and careful integration with all other clinical and radiographic data in the use of FGF-23 RT-PCR for the diagnosis of PMTMCT.

Abstract 3859: Defining groupings of oropharyngeal squamous cell carcinomas by expression patterns of human papillomavirus oncogenes

There is considerable clinical interest in the role that human papillomavirus (HPV) plays in the development of oropharyngeal cancers. A variety of assays are currently available to stratify patients based on HPV status prior to treatment. The most frequently utilized are PCR and In Situ hybridization (ISH) to detect the presence of HPV DNA sequences. The increasing clinical interest in determining HPV patient status relates to compelling evidence that a subset of patients with HPV positive tumors have better clinical outcomes. Evidence also suggests that patients with HPV positive tumors should be further divided into groupings based on levels of viral activity and that this may represent additional clinical information necessary to develop appropriate treatment plans. The most frequently applied assay to identify HPV activity in a patient sample is to detect the over-expression of the surrogate protein marker p16 by Immunohistochemisty (IHC), which has been shown to increase expression in response to HPV active infections in oropharyngeal cancer. An alternative technique to quantitatively detect the presence and level of transcriptional activity of HPV in tissue samples is to measure the expression of oncogenes E6 and E7. We have analyzed the fresh frozen tissue samples corresponding to matched tumor, normal and metastatic patient tissues using a quantitative PCR (qPCR) approach to determine the expression of HPV oncogenes and p16 gene expression. We observed that there are three groups of oropharyngeal tumors when grouped by HPV16 E6 and E7 gene expression. The first are the most rare and are tumors that contain no HPV sequences or expression of the E6 and E7 ocogenes. The second are tumors that contain HPV DNA sequences but very low expression of E6 or E7 and the third are tumors that contain HPV DNA sequence and robust expression of E6 and E7. Additionally, we found variable correlation between HPV16 E6 and E7 expression and p16 gene expression, suggesting that factors other than HPV oncogene expression may influence the expression of p16. Our results would indicate that the best assays for quantifying the activity of an HPV infection in oropharyngeal cancers would be those optimized to accurately measure either E6 and E7 transcripts or their protein products directly out of paraffin-embedded tissues.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3859. doi:10.1158/1538-7445.AM2011-3859