Application of a portable primary standard level graphite calorimeter for absolute dosimetry in a clinical low-energy passively scattered proton beam.

Objective. A calibration service based on a primary standard calorimeter for the direct determination of absorbed dose for proton beams does not exist. A new Code of Practice (CoP) for reference dosimetry of proton beams is being developed by a working party of the UK Institute of Physics and Engineering in Medicine (IPEM), which will recommend that ionisation chambers are calibrated directly in their clinical beams against the proposed Primary Standard Proton Calorimeter (PSPC) developed at the National Physical Laboratory (NPL). The aim of this work is to report on the use of the NPL PSPC to directly calibrate ionisation chambers in a low-energy passively scattered proton beam following recommendations of the upcoming IPEM CoP.Approach. A comparison between the dose derived using the proposed IPEM CoP and the IAEA TRS-398 protocol was performed, andkQvalues were determined experimentally for three types of chambers. In total, 9 plane-parallel and 3 cylindrical chambers were calibrated using the two protocols for two separate visits.Main results. The ratio of absorbed dose to water obtained with the PSPC and with ionisation chambers applying TRS-398 varied between 0.98 and 1.00, depending on the chamber type. The new procedure based on the PSPC provides a significant improvement in uncertainty where absorbed dose to water measured with a user chamber is reported with an uncertainty of 0.9% (1σ), whereas the TRS-398 protocol reports an uncertainty of 2.0% and 2.3% (1σ) for cylindrical and plane-parallel chambers, respectively. ThekQvalues found agree within uncertainties with those from TRS-398 and Monte Carlo calculations.Significance. The establishment of a primary standard calorimeter for the determination of absorbed dose in proton beams combined with the introduction of the associated calibration service following the IPEM recommendations will reduce the uncertainty and improve consistency in the dose delivered to patients.

Cardiac risk stratification in emergency resection for colonic tumours.

BACKGROUND: Despite advances in perioperative care, the postoperative mortality rate after emergency oncological colonic resection remains high. Risk stratification may allow targeted perioperative optimization and cardiac risk stratification. This study aimed to test the hypothesis that the Revised Cardiac Risk Index (RCRI), a user-friendly tool, could identify patients who would benefit most from perioperative cardiac risk mitigation. METHODS: Patients who underwent emergency resection for colonic cancer from 2007 to 2017 and registered in the Swedish Colorectal Cancer Registry (SCRCR) were analysed retrospectively. These patients were cross-referenced by social security number to the Swedish National Board of Health and Welfare data set, a government registry of mortality, and co-morbidity data. RCRI scores were calculated for each patient and correlated with 90-day postoperative mortality risk, using Poisson regression with robust error of variance. RESULTS: Some 5703 patients met the study inclusion criteria. A linear increase in crude 90-day postoperative mortality was detected with increasing RCRI score (37.3 versus 11.3 per cent for RCRI 4 or more versus RCRI 1; P < 0.001). The adjusted 90-day all-cause mortality risk was also significantly increased (RCRI 4 or more versus RCRI 1: adjusted incidence rate ratio 2.07, 95 per cent c.i. 1.49 to 2.89; P < 0.001). CONCLUSION: This study documented an association between increasing cardiac risk and 90-day postoperative mortality. Those undergoing emergency colorectal surgery for cancer with a raised RCRI score should be considered high-risk patients who would most likely benefit from enhanced postoperative monitoring and critical care expertise.

Self-reported and actual adherence to the Tokyo guidelines in the European snapshot audit of complicated calculous biliary disease.

BACKGROUND: Complicated acute biliary calculous disease poses clinical challenges. The European Society of Trauma and Emergency Surgery (ESTES) snapshot audit of complicated biliary calculous disease aims to make novel comparisons between self-reported institutional adherence to the Tokyo guidelines (TG18) and 'real-world' contemporary practice across Europe. METHODS: A preplanned analysis of a prospective observational multicentre audit that captured patients undergoing emergency admission for complicated biliary calculous disease (complicated cholecystitis, biliary pancreatitis, or choledocholithiasis with or without cholangitis) between 1 and 31 October 2018 was performed. An anonymized survey was administered to participating sites. RESULTS: Following an open call for participation, 25 centres from nine countries enrolled 338 patients. All centres completed the anonymized survey. Fifteen centres (60 per cent) self-reported that a minority of patients were treated surgically on index admission, favouring interval cholecystectomy. This was replicated in the snapshot audit, in which 152 of 338 patients (45·0 per cent) underwent index admission cholecystectomy, 17 (5·0 per cent) had interval cholecystectomy, and the remaining 169 (50·0 per cent) had not undergone surgery by the end of the 60-day follow-up. Centres that employed a dedicated acute care surgery model of care were more likely to perform index admission cholecystectomy compared with a traditional general surgery 'on call' service (57 versus 38 per cent respectively; odds ratio 2·14 (95 per cent c.i. 1·37 to 3·35), P < 0·001). Six centres (24 per cent) self-reported routinely performing blood cultures in acute cholecystitis; patient-level audit data revealed that blood cultures were done in 47 of 154 patients (30·5 per cent). No centre self-reported omitting antibiotics in the management of acute cholecystitis, and 144 of 154 (93·5 per cent) of patients in the snapshot audit received antibiotics during their index admission. CONCLUSION: Awareness of TG18 recommendations was high, but self-reported adherence and objective snapshot audit data showed low compliance with TG18 in patients with complicated acute biliary calculous disease.

ANTECEDENTES: La complicación aguda de la litiasis biliar (complicated acute biliary calculous disease, CABCD) plantea retos clínicos. Esta auditoría de la Sociedad Europea de Trauma y Cirugía de Urgencias (European Society of Trauma and Emergency Surgery, ESTES) de la CABCD tuvo como objetivo comparar el conocimiento teórico de las recomendaciones de Tokio (TG18) y la "práctica real" en Europa. MÉTODOS: Se efectuó un análisis pre-establecido de los datos de una auditoría prospectiva, observacional y multicéntrica que incluyó los pacientes ingresados de urgencia por CABCD (es decir, colecistitis complicada, pancreatitis biliar o coledocolitiasis con o sin colangitis) entre el 1 y el 31 de octubre de 2018. Además, se realizó una encuesta anónima en los centros participantes. RESULTADOS: Tras una convocatoria abierta, 25 centros de 9 países incluyeron 338 pacientes. Todos los centros completaron la encuesta anónima. El 60% de los centros reconocieron que trataban en el mismo ingreso una minoría de los pacientes y que favorecían la colecistectomía diferida. Ello se reprodujo en la auditoria, donde a 152/338 (44,9%) de los pacientes se realizó la colecistectomía en el mismo ingreso, a 17/338 (5%) se realizó una colecistectomía diferida y que a 169/338 (50%) todavía no se había realizado ninguna intervención en los 60 días de seguimiento. Los centros que seguían el Modelo de Atención Quirúrgica Urgente tenían mayores probabilidades de realizar la colecistectomía en el mismo ingreso en comparación con un servicio de cirugía general tradicional 'de guardia' (57% versus 38,4%, razón de oportunidades, odds ratio, OR 2,14 (i.c. del 95% 1,37-3,35), P < 0,001)). El 24% de los centros afirmaron realizar hemocultivos de rutina en la colecistitis aguda. Sin embargo, los datos de la auditoría revelaron que solamente 47/154 (30,5%) de los pacientes tenían hemocultivos. Ningún centro declaró no administrar antibióticos en el tratamiento de la colecistitis aguda, mientras que 144/154 (93,5%) de los pacientes de la auditoría no recibieron antibióticos durante el ingreso. CONCLUSIONES: El conocimiento de las recomendaciones de TG18 fue alto. Sin embargo, la observancia reconocida por los centros y los datos objetivos de la auditoría muestran que el cumplimiento en los pacientes con CABCD es bajo.

Tailored ultrasound learning for acute care surgeons: a review of the MUSEC (Modular UltraSound ESTES Course) project.

PURPOSE: The European Society for Trauma and Emergency Surgery (ESTES) identified the need for general and trauma surgeons involved in the management of critically ill surgical patients to embrace and learn both basic and advanced US skills. A steering group was created to address this deficit. METHODS: Modular UltraSound ESTES Course (MUSEC) is a modular blended-learning course. It incorporates pre-test/post-test examinations, pre-course online materials, didactic and interactive lectures, interactive case scenarios discussion with pathological US clips, hands-on practice on healthy volunteer models, and on original phantoms for simulating both pathological US findings and practicing US-guided interventional maneuvers. Four independent modules were provided. Surgical decision-making didactics were also included in the course curriculum. Learning gain (Δ of the rating of pre-test and post-test) was calculated for each module. An anonymous post-course satisfaction survey was also administered (16 questions with a Likert's 5-point scale of evaluation). RESULTS: Twenty-three MUSEC Courses were run in a 30 months period, training 416 doctors from 29 countries. A total of 52 modules were delivered. The mean pre-test and post-test grades were 8.3/12 and 10.7/12, respectively, yielding a significant mean learning gain of 28.9 % (p = 0.001). Post-course satisfaction survey got an overall ranking of 4.5/5. CONCLUSIONS: MUSEC is an effective and original educational format, enjoyed by candidates, that fills an educational gap for tailored US education as a procedural skill to acute care surgeons. Ongoing revisions should reduce the current limitations and increase the educational value, in terms of number of modules and post-course credentialing.

A comparison of clinical-pathological characteristics between symptomatic and interval breast cancer.

BACKGROUND: An association between interval breast cancers (cancer detected after a normal mammogram and before the next scheduled mammogram) and tumour aggressiveness has been postulated which may reflect their relatively poor overall prognosis. The aim of this study was to evaluate known prognostic features of screen detected breast cancers compared to interval breast cancers. METHODS: Patients diagnosed with breast cancer between January 2010 and 2013 at a single unit of the National Breast Screening Program (NBSP) in Ireland and those between the ages of 50 and 65 diagnosed at a symptomatic breast clinic were included in the study. Patients who had not had a screening mammogram within the proceeding two years or had a previous history of breast cancer were excluded. Data were retrospectively collected on patient demographics, tumour type, grade, hormone receptor status and stage of disease at presentation. RESULTS: There were 915 patients included in the study, with 92% (n = 844) diagnosed through the NBSP. Ductal carcinoma in-situ accounted for 19% (n = 160) of screen-detected breast cancers but only 2.8% of interval cancers (p < 0.05). The most common type of invasive cancer was invasive ductal carcinoma. Tumour grade was significantly higher in interval breast cancers (p < 0.05). Interval cancers were identified at a significantly higher stage (Stage 1 versus 2; p < 0.001) than screen-detected cancers. Interval breast cancers were less likely to be ER positive (76% versus 81%; p < 0.05) and significantly more likely to over-express HER2 (20% vs 10%, p < 0.05) than screen-detected cancers. CONCLUSION: This study highlights the fact that interval cancers appear to have a number of adverse prognostic markers for overall breast cancer survival when compared to women with screen-detected breast cancers. Interval cancers were more likely to be invasive, of a higher grade and stage and with a greater predominance of HER2 and triple negative molecular subtypes. Therefore this heterogeneous group of tumours may be biologically more aggressive and account disproportionately to overall breast cancer mortality.

Penetrating stab injuries at a single urban unit: are we missing the point?

BACKGROUND: Penetrating trauma--the classical presentation of disorganised crime--can pose a challenge in their management due to their complexity and unpredictability. AIM: We examined the experience of one urban unit in the management of penetrating injuries to draw conclusions pertinent to other Irish centres. METHODS: A retrospective study was performed of all penetrating injuries presenting to the Emergency Department (ED) of Connolly Hospital, Dublin between January 2009 and December 2012. Information was collected from the Hospital Inpatient Enquiry database, theatre logbooks and ED records. RESULTS: One hundred and four patients presented with penetrating injuries in the given period. Four mortalities were recorded. Abdominal injury was recorded in 22% of patients; 26% had multiple injuries not involving the abdomen; 11% had an isolated thoracic injury. Fifty-seven percent required surgery, of which 40% required emergency or early surgical intervention. Laparotomy and laparoscopy were required in 14 and 7%, respectively; 5% required thoracotomy of which two had penetrating cardiac injuries, both of whom survived. CONCLUSIONS: Although many patients with penetrating trauma can be safely managed conservatively, our study shows that over half required surgical intervention. These data highlight the need for a trauma team in each Irish centre receiving trauma with a clear need for general surgeons on emergency on-call rotas to be experienced in trauma management. There is an urgent need to centralise the management of trauma to a limited number of designated trauma centres where expertise is available by surgeons with a special interest in trauma management.

Malignant melanoma: factors affecting the surgical interval from excision biopsy to definitive surgical management.

INTRODUCTION: Surgery remains the mainstay of treatment for malignant melanoma. Despite previous studies examining the surgical interval (SI) between the diagnostic excision biopsy (DEB) and definitive surgical management there remains few guidelines regarding an optimal time interval. The aim of this study was to determine the SI between DEB and definitive surgery and elucidate factors associated with delays in management of malignant melanoma. METHODS: A retrospective study of 107 consecutive patients who had a DEB and subsequent wide local excision between January 2011 and June 2012 was performed. Mode of referral and dates of diagnostic biopsy/definitive surgery were documented. Patient demographics and tumour characteristics were reviewed. RESULTS: The mean age was 59.6 years, and male:female ratio was 1:1.3. Median duration of the SI was 41 ± 27 days (range 6-137 days). The SI was increased when dermatologists performed the DEB as opposed to general surgeons (p = 0.035). The anatomic location of the lesion predicted the SI, with lesions of the head/neck undergoing definitive excision 48 ± 32.3 days after DEB vs. 37.5 ± 22.6 days for all other sites (p = 0.001). Neither demographic factors nor histopathological prognostic features affected the SI. Reasons for a prolonged SI included referrals to different services and time for pre-operative planning. CONCLUSIONS: Significant variations were noted in the SI predominantly accounted for by mode of referral and location of the malignant melanoma. Further investigation is required to elucidate factors affecting the SI and its subsequent effect on patient outcomes.

Chemoradiotherapy, with adjuvant surgery for local control, confers a durable survival advantage in adenocarcinoma and squamous cell carcinoma of the oesophagus.

INTRODUCTION: Oesophageal cancer usually presents with systemic disease, necessitating systemic therapy. Neo-adjuvant chemoradiotherapy improves short-term survival, but its long-term impact is disputed because of limited accrual, treatment-protocol heterogeneity and a short follow-up of randomised trials. AIMS: Long-term results of two simultaneous randomised controlled trials (RCTs) comparing neo-adjuvant chemo-radiotherapy and surgery (MMT) with surgical monotherapy were examined, and the response of adenocarcinoma (AC) and squamous cell carcinoma (SCC) to identical regimens compared. METHODS: Between 1990 and 1997, two RCTs were undertaken on 211 patients. Patients with AC (n=113) or SCC (n=98) were separately-randomised to identical protocols of MMT or surgical monotherapy. RESULTS: 211 patients were followed to 206 months; 104 patients were randomised to MMT (58 AC and 46 SCC, respectively) and 107 to surgery. MMT provided a significant survival-advantage over surgical monotherapy for AC (P=0.004), SCC (P=0.01). There was a 54% relative risk-reduction in lymph-node metastasis following MMT, compared with surgery (64% versus 29%, P<0.001). MMT produced a pathologic complete response (pCR) in 25% and 31% of AC and SCC, respectively. Survival advantage accrued to MMT, pCR and node-negative patients: AC pCR versus surgical monotherapy (P=0.001); residual disease following MMT versus surgical monotherapy (P=0.008); SCC pCR versus surgical monotherapy (P=0.033). CONCLUSIONS: A survival advantage for MMT persisted long-term in AC and was replicated in SCC. MMT produced loco-regional tumour down-staging to extinction in 25-31% of patients, potentially permitting personalised treatment in this cohort that avoids the morbidity and mortality associated with resection. Node-negative patients with residual localised disease following MMT had a survival advantage over node-negative patients following surgery alone, supporting a systemic effect on micro-metastatic disease.

Biliary epithelial metastasis of squamous carcinoma of the anus.

INTRODUCTION: The liver and biliary tree are common sites of initial metastasis for many primary tumors. However, we recently encountered a patient who presented with biliary-tree tumor encasement as a first metastasis from squamous carcinoma of the anus. METHODS: To our knowledge, this has not been previously described in the literature. CONCLUSIONS: As obstructive jaundice is a relatively common presenting sign in the emergency room and in general surgical clinics, we thus recommend early consideration of metastatic disease as a differential diagnosis in patients post-chemoradiotherapy for anal carcinoma who present with obstructive jaundice.

Collins' sign: validation of a clinical sign in cholelithiasis.

BACKGROUND: Cholelithiasis typically presents with right upper quadrant pain, as can pain from other right upper quadrant organs. Pain of cholelithiasis is often referred to tip of scapula. Professor Paddy Collins drew attention to fact that patients with gallstone pain would attempt to demonstrate this by placing their hand behind the back and thumb pointing upwards. This became known amongst his students as Collins' sign. AIM: To evaluate accuracy of Collins' sign as indicator of cholelithiasis. PATIENTS AND METHODS: Case-control study performed on 202 patients with symptomatic cholelithiasis and 200 control patients (with oesophagitis, gastritis or duodenal ulcer). Questionnaire examined pain pattern in both groups. The results analysed using t test and χ(2) test. RESULTS: Collins' sign was positive in 51.5% of gallstone patients and 7.5% of control group (P < 0.001). CONCLUSIONS: Collins' sign was positive in over half of all patients with cholelithiasis and was useful discriminator in diagnosis of gallstones.

Calibration of the NPL secondary standard radionuclide calibrator for 125I seeds used for prostate brachytherapy. National Physical Laboratory.

In the therapeutic use of radionuclides, by far the most rapid growth in recent years is that of 125I seeds used for the treatment of prostate cancer. Large numbers of these seeds are used in each treatment and there is a need for a simple but accurate means of confirming their dose rates. This mechanism requires a transfer device for which the calibration factors are traceable to national standards. The NPL secondary standard radionuclide calibrator, because of its guaranteed reproducibility and traceable calibration procedure, is ideally suited for this purpose. A series of characterisation measurements have been performed on the NPL radionuclide calibrator in order to estimate the uncertainty levels that can be achieved and these are presented together with the relevant calibration factors for some typical seeds.

Dosimetry of beta-ray ophthalmic applicators: comparison of different measurement methods.

An international intercomparison of the dosimetry of three beta particle emitting ophthalmic applicators was performed, which involved measurements with radiochromic film, thermoluminescence dosimeters (TLDs), alanine pellets, plastic scintillators, extrapolation ionization chambers, a small fixed-volume ionization chambers, a diode detector and a diamond detector. The sources studied were planar applicators of 90Sr-90Y and 106Ru-106Rh, and a concave applicator of 106Ru-106Rh. Comparisons were made of absolute dosimetry determined at 1 mm from the source surface in water or water-equivalent plastic, and relative dosimetry along and perpendicular to the source axes. The results of the intercomparison indicate that the various methods yield consistent absolute dosimetry results at the level of 10%-14% (one standard deviation) depending on the source. For relative dosimetry along the source axis at depths of 5 mm or less, the agreement was 3%-9% (one standard deviation) depending on the source and the depth. Crucial to the proper interpretation of the measurement results is an accurate knowledge of the detector geometry, i.e., sensitive volume and amount of insensitive covering material. From the results of these measurements, functions which describe the relative dose rate along and perpendicular to the source axes are suggested.

Radiotherapy review on national surgical adjuvant breast and bowel project (NSABP) phase III breast cancer clinical trials: is there a need for submission of portal/simulation films?

In all National Surgical Adjuvant Breast and Bowel Project (NSABP) breast cancer trials in which patients are treated with lumpectomy and postoperative breast irradiation, the quality assurance requirements dictate submission of a completed radiotherapy data form with the stated administered doses, the volumes treated, treatment prescription and daily treatment record sheets, dosimetry and calculation sheets, isodose distributions on the breast contour, photos of the patient in the treatment position, and portal or simulation films. A review of radiotherapy data on 1,982 patients who had lumpectomies accrued to seven recent NSABP breast cancer studies revealed only 2 patients who were judged to have inadequate fields. In both cases, a very small portion of the breast tissue was not included in the irradiated volume as demonstrated by the submitted films. On this basis, it was argued that submission of portal or simulation films for patients receiving postlumpectomy breast irradiation is not necessary. However, there was concern as to the incidence of patients with a possible excess amount of lung tissue included in the irradiated volume. To address this concern, the amount of irradiated lung was determined for the first 208 patients who had lumpectomies, with submitted data entered into the recent NSABP pathologic node-positive protocol B-28. Current NSABP radiation therapy guidelines suggest limiting the thickness of the irradiated lung in the portal beams to < or =3 cm. Only two patients (<1%) were found to have >3 cm of irradiated lung tissue in the treatment volume. Portal film submission is a considerable inconvenience to the individual institutions and is costly in terms of shipping, handling, and storage. These results indicate that submission of portal films is not a necessary part of quality assurance in NSABP breast cancer protocols. The NSABP has therefore eliminated the requirement for routine submission of portal films in protocols for which radiotherapy is not part of the test question.

A comparison of CD34+ cell selected and unselected autologous peripheral blood stem cell transplantation for multiple myeloma: a case controlled analysis.

Following ASCT for multiple myeloma, it is unclear whether relapse is due solely to the presence of residual myeloma cells after myeloablation, or whether it is in part attributable to contamination of the stem cell harvest with viable malignant cells. Positive selection of CD34+ cells markedly reduces plasma cell contamination. We performed a case controlled analysis in which 15 patients with myeloma who underwent autologous PBSCT with CD34+cell selection using the Ceprate System (index group), were compared with 15 matched controls. All subjects received an identical preparative regimen. The median times to neutrophils >/=0.5 x 10(9)/l and unsupported platelets >/=50 x 10(9)/l were 14 and 23 days for the CD34+cell selected group and 11 (P = 0.03) and 14 (P = 0.029) for the case controls. Median follow-up of purged patients from autologous PBSCT was 32 months (range 18-43). At 36 months, the probability of PFS was 47 +/- 14% and 46 +/- 14% in the index and control groups (P = 0.44). The 3 year probability of OS was 69 +/- 13% for the CD34+ cell selected arm and 66 +/- 12.4% in unpurged patients (P = 0.91). Median PFS for the cell selected group is 24 months (CI 19.1-36.0), and 29 months for controls (CI 7.1-50.9). Eleven patients undergoing cell selection remain alive, seven of whom are progression free. At the same time-point after unpurged autologous PBSCT, the corresponding figures are 12 patients alive, with seven remaining progression free. Autologous PBSCT with CD34+ cell selection is both feasible and safe, but results in delayed engraftment as compared to case controls. The 3 year probability of PFS and OS in the cell selected arm was similar to that of the unpurged controls. Our findings indicate that autologous PBSCT with CD34+ cell selection appears not to have any favourable effect on disease progression. However, the results of this case controlled analysis should be cautiously interpreted, and the role of CD34+ selection in autologous PBSCT should be further investigated by large randomised trials.