Preemptive Surgery Research Articles

CT features associated with contralateral recurrence of spontaneous pneumothorax.

Spontaneous pneumothorax recurs in 30 to 54% of patients without surgery. Identifying individuals likely to suffer a recurrence, who might benefit from pre-emptive surgery, is challenging. Previous meta-analysis suggested a relationship between contralateral recurrence and specific computed tomography (CT) findings. We analysed CT images and recurrence rates 243 patients seen by our tertiary referral pneumothorax service. We validated the meta-analysis observation that contralateral lung cysts are associated with a higher risk of contralateral recurrence in younger individuals. Furthermore, we observed the size of contralateral cysts to be associated with increased contralateral recurrence in younger patients. The detection of contralateral lung cysts might therefore help identify younger patients more likely to benefit from pre-emptive surgery.

Significant unfavorable geometrical changes in ascending aorta despite stable diameter at follow-up

ObjectiveThe clinical importance of following up on the ascending aortic diameter lies in the fundamental presumption that wall pathology eventually manifests as a change in shape. However, the diameter describes the vessel locally, and the 55 mm criterion fails to prevent most dissections. We hypothesized that geometric changes across the ascending aorta are not necessarily imprinted on its diameter; i.e. the maximum diameter correlates weakly and insignificantly with elongation, surface stretching, engorgement, and tortuosity. MethodsTwo databases were interrogated for patients who had undergone at least 2 ECG-gated CT scans. The absence of motion artifacts permitted the generation of exact copies of the ascending aorta which then underwent three-dimensional analysis producing objective and accurate measurements of the centreline length, surface, volume, and tortuosity. The correlations of these global variables with the diameter were explored. ResultsTwenty-two patients, 13 male and 9 female, were included. The mean age at the first and last scan was 63.7 and 67.1 y, respectively. The mean diameter increase was approximately 1 mm/y. There were no dissections, while 7 patients underwent preemptive surgery. The yearly change rate of the global variables, normalized to height if applicable, showed statistically insignificant, weak, or negligible correlation with diameter increments at follow-up. Most characteristically, a patient's aorta maintained its diameter, while undergoing 1 mm/y elongation, 151 mm2/(y·m) stretching, 2366 mm3/(y·m) engorgement, and 0.02/y tortuosity. ConclusionMaximum diameter provides a local description of the ascending aorta and cannot fully portray the pathological process across this vessel. Following up the diameter is not suggestive of length, surface, volume, and tortuosity changes.

Molecular Imaging of Aortic Aneurysm and Its Translational Power for Clinical Risk Assessment.

Aortic aneurysms (AAs) are dilations of the aorta, that are often fatal upon rupture. Diagnostic radiological techniques such as ultrasound (US), magnetic resonance imaging (MRI), and computed tomography (CT) are currently used in clinical practice for early diagnosis as well as clinical follow-up for preemptive surgery of AA and prevention of rupture. However, the contemporary imaging-based risk prediction of aneurysm enlargement or life-threatening aneurysm-rupture remains limited as these are restricted to visual parameters which fail to provide a personalized risk assessment. Therefore, new insights into early diagnostic approaches to detect AA and therefore to prevent aneurysm-rupture are crucial. Multiple new techniques are developed to obtain a more accurate understanding of the biological processes and pathological alterations at a (micro)structural and molecular level of aortic degeneration. Advanced anatomical imaging combined with molecular imaging, such as molecular MRI, or positron emission tomography (PET)/CT provides novel diagnostic approaches for in vivo visualization of targeted biomarkers. This will aid in the understanding of aortic aneurysm disease pathogenesis and insight into the pathways involved, and will thus facilitate early diagnostic analysis of aneurysmal disease. In this study, we reviewed these molecular imaging modalities and their association with aneurysm growth and/or rupture risk and their limitations. Furthermore, we outline recent pre-clinical and clinical developments in molecular imaging of AA and provide future perspectives based on the advancements made within the field. Within the vastness of pre-clinical markers that have been studied in mice, molecular imaging targets such as elastin/collagen, albumin, matrix metalloproteinases and immune cells demonstrate promising results regarding rupture risk assessment within the pre-clinical setting. Subsequently, these markers hold potential as a future diagnosticum of clinical AA assessment. However currently, clinical translation of molecular imaging is still at the onset. Future human trials are required to assess the effectivity of potentially viable molecular markers with various imaging modalities for clinical rupture risk assessment.

Клинические разборы. По-прежнему ли они необходимы?

Clinical case studies and the history of their emergence and development are analyzed. Evidence is provided for the risk of clinical case studies’ abandonment due to universal availability of medical imaging methods. Contribution of clinical case studies both to appropriate treatment tactics and to physician’s knowledge and experience is shown. In the context of preventive medicine, when the morphological substrate of the disease is detected in apparently healthy individuals, clinical case studies make it possible to perform preemptive surgery or to avoid it on a reasonable basis, thereby helping to resolve the situation of incidental findings to the benefit of the patient.

Determining the optimal interval for imaging surveillance of ascending aortic aneurysms.

BackgroundCardiovascular guidelines recommend (bi-)annual computed tomography (CT) or magnetic resonance imaging (MRI) for surveillance of the diameter of thoracic aortic aneurysms (TAAs). However, no previous study has demonstrated the necessity for this approach. The current study aims to provide patient-specific intervals for imaging follow-up of non-syndromic TAAs.MethodsA total of 332 patients with non-syndromic ascending aortic aneurysms were followed over a median period of 6.7 years. Diameters were assessed using all available imaging techniques (echocardiography, CT and MRI). Growth rates were calculated from the differences between the first and last examinations. The diagnostic accuracy of follow-up protocols was calculated as the percentage of subjects requiring pre-emptive surgery in whom timely identification would have occurred.ResultsThe mean growth rate in our population was 0.2 ± 0.4 mm/year. The highest recorded growth rate was 2.0 mm/year, while 40.6% of patients showed no diameter expansion during follow-up. Females exhibited significantly higher growth rates than men (0.3 ± 0.5 vs 0.2 ± 0.4 mm/year, p = 0.007). Conversely, a bicuspid aortic valve was not associated with more rapid aortic growth. The optimal imaging protocol comprises triennial imaging of aneurysms 40–49 mm in diameter and yearly imaging of those measuring 50–54 mm. This strategy is as accurate as annual follow-up, but reduces the number of imaging examinations by 29.9%.ConclusionsIn our population of patients with non-syndromic TAAs, we found aneurysm growth rates to be lower than those previously reported. Yearly imaging does not lead to changes in the management of small aneurysms. Thus, lower imaging frequencies might be a good alternative approach.

Characterization of Ascending Aortic Flow in Patients With Degenerative Aneurysms: A 4D Flow Magnetic Resonance Study.

Degenerative thoracic aortic aneurysm (TAA) patients are known to be at risk of life-threatening acute aortic events. Guidelines recommend preemptive surgery at diameters of greater than 55 mm, although many patients with small aneurysms show only mild growth rates and more than half of complications occur in aneurysms below this threshold. Thus, assessment of hemodynamics using 4-dimensional flow magnetic resonance has been of interest to obtain more insights in aneurysm development. Nonetheless, the role of aberrant flow patterns in TAA patients is not yet fully understood. A total of 25 TAA patients and 22 controls underwent time-resolved 3-dimensional phase contrast magnetic resonance imaging with 3-directional velocity encoding (ie, 4-dimensional flow magnetic resonance imaging). Hemodynamic parameters such as vorticity, helicity, and wall shear stress (WSS) were calculated from velocity data in 3 anatomical segments of the ascending aorta (root, proximal, and distal). Regional WSS distribution was assessed for the full cardiac cycle. Flow vorticity and helicity were significantly lower for TAA patients in all segments. The proximal ascending aorta showed a significant increase in peak WSS in the outer curvature in TAA patients, whereas WSS values at the inner curvature were significantly lower as compared with controls. Furthermore, positive WSS gradients from sinotubular junction to midascending aorta were most prominent in the outer curvature, whereas from midascending aorta to brachiocephalic trunk, the outer curvature showed negative WSS gradients in the TAA group. Controls solely showed a positive gradient at the inner curvature for both segments. Degenerative TAA patients show a decrease in flow vorticity and helicity, which is likely to cause perturbations in physiological flow patterns. The subsequent differing distribution of WSS might be a contributor to vessel wall remodeling and aneurysm formation.

Predicting Fracture Healing with Biomarkers: The Potential for Precision Medicine to Assess Patient Risk of Fracture Nonunion

Objective: 
 To provide a comprehensive survey of the literature related to the current efficacy of biomarkers for predicting fracture healing. 
 Methods: 
 EMBASE and PubMed, were searched using the following terms: fractures, biomarkers, ununited, and nonunion with the assistance of a medical librarian. The initial search yielded 199 records. Additional search of Google Scholar and review of the references yielded zero additional records. The 165 unique records were screened, of which 105 were excluded due to experimental treatments, non-fracture related bone healing, animal studies, and study group design failure to compare union versus nonunion fracture outcomes. This left 21 articles for full review. 
 Results: 
 19 serum biomarkers were reviewed for nonunion predicative capability. From this cohort 9 biomarkers had promising results including; bone formation markers OC and PINP, bone resorption markers TRAP and OPN, growth factors VEGF and PGF-1, TEMRA and TReg cells, and miR-193a-3p. 15 SNPs on 11 genes were examined. The polymorphisms with the greatest potential for increased risk of nonunion based on odds ratio include; SMAD6 rs2053423 T/T genotype OR = 10.27. IL-1b rs2853550 T allele OR = 5.9. NOG rs1372857 G/G genotype OR = 4.56. NOS rs2297514 OR = 3.98. and PDGF CCG haplotype OR = 3.57 
 Conclusion: 
 There remains an unmet clinical need to develop predictive parameter(s) for bone healing that are objective, reproducible, preferably continuous, unique to the individual, and optimally based on a readily accessible biologic measurement. Ultimately yielding a biomarker predictive of future nonunion that is additive, or superior, to that of known clinical risk factors for nonunion. 
 Clinical Implications: 
 Accurate biomarkers could identify patients at early times post-injury who may benefit from intervention to promote healing, thus circumventing unnecessary delays in nonunion intervention. Additionally, biomarkers could eliminate preemptive surgery in patients with early slow progression who are otherwise on a healing trajectory.

Efficacy of preemptive endoscopic submucosal dissection and surgery for synchronous colorectal neoplasms

Background and aim If patients with surgically resectable colorectal cancershave synchronous colorectal neoplasms that are difficult to remove by endoscopic mucosal resection, preemptive endoscopic submucosal dissection (ESD) can avoid excessive colorectal resection. The aim of this study was to evaluate the efficacy of the strategy of preemptive ESD and surgery for synchronous colorectal neoplasms. Methods Patients who underwent preemptive ESD and surgery for synchronous colorectal neoplasms between September 2002 and December 2017 were enrolled in this retrospective cohort study. The proportion of cases in which extended surgery could be avoided following curative ESD was calculated. Clinicopathological characteristics were evaluated for all patients and long-term outcomes were analyzed for patients who underwent curative ESD and surgery. Results A total of 45 consecutive patients with 47 endoscopically-resected lesions and 46 surgically-resected lesions were retrospectively evaluated. Curative ESD was achieved in 44 lesions (93.6%) and an extended surgical procedure could be avoided in 42 patients (93.3%). Intraoperative perforation occurred in two lesions (4.3%), delayed perforation in one lesion (2.1%), and delayed bleeding in two lesions (4.3%). Final stages were as follows: stage 0, 3 patients (7.1%); stage I, 23 patients (54.8%); stage II, 3 patients (7.1%); stage III, 12 patients (28.6%); and stage IV, 1 patient (2.4%). The 5-year overall survival rates of patients with all pathological stages, stage 0–II, and stage III–IV were 93.7%, 100%, and 79.1%, respectively. Conclusion The strategy of preemptive ESD and surgery for synchronous colorectal neoplasms is minimally invasive and has a favorable prognosis.

Is Primary Tumor Excision and Specific Metastases Sites Resection Associated With Improved Survival in Stage Ⅳ Colorectal Cancer? Results From SEER Database Analysis.

We aimed to explore the prognostic value of primary tumor and specific metastases excision on survival among patients with stage IV colorectal cancer (CRC) in the Surveillance, Epidemiology, and End Results (SEER) database. Patients with stage IV CRC were selected using SEER database between 2010 and 2013. Survival rate was calculated according to the Kaplan-Meier method, and differences between curves were tested by the log-rank test. Cox proportional hazards model was used in the multivariable analysis. Included in this study were 27 878 patients with distant metastatic CRC. Among the single organ site of metastatic CRC, patients with solitary metastasis of lung showed the highest median overall survival (OS). Both primary and metastatic sites surgical resection for patients with liver, lung, and simultaneous liver and lung metastases had better median OS. Age younger than 65 years, Asian and Pacific Islander, distal colon and rectum, and palliative primary tumor and metastatic lesions resection were associated with better OS after multivariate analysis. Palliative primary tumor and metastatic lesions resection had a significant survival benefit compared with nonsurgical group in selected patients. These findings support the use of preemptive surgery in the management of highly selected metastatic CRC patients.

Fate of contralateral asymptomatic bullae in patients with primary spontaneous pneumothorax.

This retrospective cohort study aimed to analyse the impact of asymptomatic blebs/bullae on the occurrence of primary spontaneous pneumothorax (PSP) by monitoring the natural course of contralateral blebs/bullae in patients with ipsilateral pneumothorax. From January 2003 to December 2017, 1055 patients [age 19.6 ± 3.98 years (mean ± standard deviation), 953 men] experiencing the first episode of unilateral PSP were enrolled in this study, excluding patients aged 30 years or more. The presence, number and maximal size of the blebs/bullae were investigated in contralateral asymptomatic lungs based on high-resolution computed tomography. Multiple and single blebs/bullae were noted in contralateral lungs in 425 (40.3%) and 88 (8.3%) patients, respectively. The median follow-up period was 44.0 (interquartile range 71.5) months. The 1-, 3- and 5-year cumulative occurrence rates of PSP in contralateral lungs were 7.9%, 13.7% and 16.7%, respectively. On multivariable analysis, younger age [hazard ratio (HR) 1.19, 95% confidence interval (CI) 1.12-1.27; P < 0.001) and multiple bullae (HR 4.42, 95% CI 3.06-6.38; P < 0.001) were independent risk factors for spontaneous pneumothorax in the contralateral lung. The 5-year cumulative occurrence rates of PSP were significantly higher in patients with multiple blebs/bullae than in those with no or a single bleb/bulla (28.2% vs 8.5%, respectively; P < 0.001). Asymptomatic blebs/bullae often lead to PSP. If the patient is eligible for surgery for pneumothorax, preemptive surgery for contralateral bullae could be considered, especially in patients with multiple blebs/bullae.

Management of intussusception in patients with melanoma.

Increased cross-sectional imaging for surveillance of metastatic melanoma has led to more diagnoses of asymptomatic intussusception. We performed a multi-institutional retrospective review of patient records with a history of metastatic melanoma and a diagnosis of intussusception. Patients were divided into three groups: 1) asymptomatic patients without current evidence of melanoma (no evidence of disease [NED]); 2) asymptomatic intussusception and known active metastatic melanoma; 3) symptomatic intussusception and known active metastatic melanoma; the number of patients requiring surgery and intraoperative findings were recorded. We reviewed 73 patients diagnosed with intussusception from 2004 to 2017. Among asymptomatic patients with NED (n = 16), 14 spontaneously resolved and 2 underwent pre-emptive surgery without abnormal intraoperative findings. Of asymptomatic patients with active metastatic disease (n = 32), 25 were initially observed and 7 underwent pre-emptive surgery and 9 of the 25 initially observed patients required surgery for development of symptoms. In this group, all 16 patients undergoing surgery (50% of the group) had intraoperative findings of intussusception and/or metastatic intestinal melanoma.. All symptomatic patients with metastatic melanoma (n = 25) underwent surgery; all had intraoperative findings of intussusception and/or metastatic melanoma except 1 (Meckel's diverticulum). Asymptomatic patients with NED do not require surgery and intussusception will likely resolve spontaneously. Asymptomatic patients with known metastatic melanoma may be initially observed, but a low threshold for surgery should be maintained. Symptomatic patients with known metastases should undergo surgery.

Vascular access for hemodialysis in the elderly

ObjectiveThe objective of this study was to compare the outcomes of arteriovenous fistulas (AVFs) with arteriovenous grafts (AVGs) in a large population-based cohort of elderly patients in the United States. MethodsA retrospective analysis was performed of all patients ≥75 years old in the prospectively maintained United States Renal Database System who had an AVF or AVG placed for hemodialysis (HD) access between January 2007 and December 2011. Outcomes were mortality, conduit patency, maturation, time to catheter-free dialysis, and infection. A χ2 test, Student t-test, Kaplan-Meier analysis, and multivariable Cox regression analysis were employed. ResultsOf the 124,421 patients studied, there were 19,173 (15%) AVF initiates, 4480 (4%) AVG initiates, 29,872 (24%) AVF converts, 10,712 (9%) AVG converts, and 59,824 (48%) patients who persisted on HD catheters. Compared with AVF initiates, relative mortality was significantly higher for AVG initiates (adjusted hazard ratio [aHR], 1.24; P < .001), AVF converts (aHR, 1.36; P < .001), AVG converts (aHR, 1.62; P < .001), and catheter-persistent patients (aHR, 2.23; P < .001). Primary patency (aHR, 1.21; P < .001) and primary assisted patency (aHR, 1.31; P < .001) were higher for AVF. Secondary patency was higher for AVGs within the first 4 months (aHR, 1.12; P < .001) but higher for AVFs beyond that time point (aHR, 1.25; P < .001). Maturation rate and median time to maturation were 80% vs 84% (P < .001) and 46 vs 26 days (P < .001) for AVF vs AVG. ConclusionsPre-emptive AVF remains the best mode of HD in elderly patients who can tolerate surgery. Patients who cannot tolerate pre-emptive surgery or have to initiate HD on an urgent basis with a catheter should convert to AVF when it is feasible if life expectancy is >4 months. If life expectancy is <4 months, surgical risk and quality of life should be considered in making the decision to persistently dialyze through HD catheter or to convert to AVG.

Decision-making algorithm for ascending aortic aneurysm: Effectiveness in clinical application?

ObjectiveThe risk of rupture and dissection in ascending thoracic aortic aneurysms increases as the aortic diameter exceeds 5 cm. This study evaluates the clinical effectiveness of a specific algorithm based on size and symptoms for preemptive surgery to prevent complications. MethodsA total of 781 patients with nondissecting ascending thoracic aortic aneurysms who presented electively for evaluation to our institution from 2011 to 2017 were triaged to surgery (n = 607, 77%) or medical observation (n = 181, 24%) based on a specific algorithm: surgery for large (>5 cm) or symptomatic aneurysms. A total of 309 of 781 patients did not undergo surgery. Of these, 128 (16%) had been triaged to prompt repair but did not undergo surgery for a variety of reasons (“surgery noncompliant and overwhelming comorbidities” group). Another 181 patients (24%) were triaged to medical management (“medical” group). ResultsIn the “surgery noncompliant and overwhelming comorbidities” versus the “medical” group, mean aortic diameters were 5 ± 0.5 cm versus 4.45 ± 0.4 cm and aortic events (rupture/dissection) occurred in 17 patients (13.3%) versus 3 patients (1.7%), respectively (P < .001). Later elective surgeries (representing late compliance in the “surgery noncompliant and overwhelming comorbidities group” or onset of growth or symptoms in the “medical” group) were conducted in 21 patients (16.4%) versus 15 patients (8.3%) (P = .04), respectively. Death ensued in 20 patients (15.6%) versus 6 patients (3.3%) (P < .001), respectively. In the “surgery noncompliant and overwhelming comorbidities” group, 7 of 20 patients died of definite aortic causes compared with none in the “medical” group. ConclusionsPatients with ascending thoracic aortic aneurysms who did not follow surgical recommendations experienced substantially worse outcomes compared with medically triaged candidates. The specific algorithm based on size and symptoms functioned effectively in the clinical setting, correctly identifying both at-risk and safe patients.

Contribution of diffusion-weighted imaging to conventional MRI for detection of haemorrhagic infarction in ovary torsion

BackgroundTo assess the role of DWI in differentiation haemorrhagic ovary infarction from non-haemorrhagic one.MethodsFor this prospectively designed study, of 117 female patients who presented with acute lower quadrant pain and underwent MRI for suspicion of ovary torsion, results of only 29 patients (mean age, 24.7; SD, ±5.7; age range, 18–37), with surgical and pathological confirmation of adnexal torsion, were included to the study. All patients underwent DWI after conventional MRI. Quantitative and qualitative analysis of both the torsed and contralateral normal ovary were performed. Results of conventional MRI and DWI were noted.ResultsAt operation 15 patients were found to have haemorrhagic infarction while 14 had non-haemorrhagic infarction. Of the 29 patients, 17 torsed ovaries could be salvaged in a viable state. We found statistically significant correlation of the ADC values, between haemorrhagic and non-haemorrhagic ovary infarction. The ADC values were significantly lower in patients with haemorrhagic infarction than non-haemorrhagic ones (p < 0.001). Using an ADC threshold of 1.27, the sensitivity of DWI for haemorrhagic infarction was 0.93 and specificity 0.85.ConclusionDWI may be used with a significant success for the preoperative diagnosis of haemorrhagic infarction. This may be alerting for pre-emptive surgery in avoiding serious complications and preventing irreversible structural damage of the ovary.

Large intragenic deletion of CDC73 (exons 4\u201310) in a three-generation hyperparathyroidism-jaw tumor (HPT-JT) syndrome family

BackgroundInactivating mutations of CDC73 cause Hyperparathyroidism-Jaw Tumour syndrome (HPT-JT), Familial Isolated Hyperparathyroidism (FIHP) and sporadic parathyroid carcinoma. We conducted CDC73 mutation analysis in an HPT-JT family and confirm carrier status of the proband’s daughter.MethodsThe proband had primary hyperparathyroidism (parathyroid carcinoma) and uterine leiomyomata. Her father and daughter had hyperparathyroidism (parathyroid adenoma) but no other manifestations of HPT-JT. CDC73 mutation analysis (sequencing of all 17 exons) and whole-genome copy number variation (CNV) analysis was done on leukocyte DNA of the three affecteds as well as the proband’s unaffected sister.ResultsA novel deletion of exons 4 to 10 of CDC73 was detected by CNV analysis in the three affecteds. A novel insertion in the 5’UTR (c.-4_-11insG) that co-segregated with the deletion was identified. By in vitro assay the 5’UTR insertion was shown to significantly impair the expression of the parafibromin protein. Screening for the mutated CDC73 confirmed carrier status in the proband’s daughter and the biochemistry and ultrasonography led to pre-emptive surgery and resolution of the hyperparathyroidism.ConclusionsA novel gross deletion mutation in CDC73 was identified in a three-generation HPT-JT family emphasizing the importance of including screening for large deletions in the molecular diagnostic protocol.

Call to lower threshold for pre-emptive surgery.

The threshold for pre-emptive surgery to remove the ovaries and fallopian tubes of women aged 40 and over who are at high risk of developing ovarian cancer should be halved, say UK researchers.

Management of Cholelithiasis in the Diabetic Patients

In the recent past, dramatic advances in research have elucidated the prognosis of gallstone disease and have permitted a more selective choice of persons for treatment based on symptom status and projected prognosis. Ultrasound - detected- incidental gallstones are infrequently clinically significant but this finding has prompted the surgeons to have a liberal attitude towards the operative indications for cholelithiasis particularly after the advent of laparoscopy. At the same time, the management of gallstones in the diabetics still remains controversial. Early retrospective studies reported an alarmingly high incidence of gallstones in diabetics as compared with general population and in view of profound morbidity and mortality rates observed in the diabetics, prophylactic cholecystectomy was generally recommended. However, recent evidence-based studies challenged this approach and have concluded that prophylactic cholecystectomy is not justified in diabetic patients with asymptomatic gallstones. It is inferred that, as in general population, asymptomatic cholelithiasis in diabetics should be managed expectantly and preemptive surgery should not be routinely performed. However, early laparoscopic cholecystectomy is preferred in cases of symptomatic cholelithiasis.

Early detection and prevention of pancreatic cancer: is it really possible today?

Pancreatic cancer is the 4(th) leading cause of cancer-related death in Western countries. Considering the low incidence of pancreatic cancer, population-based screening is not feasible. However, the existence of a group of individuals with an increased risk to develop pancreatic cancer has been well established. In particular, individuals suffering from a somatic or genetic condition associated with an increased relative risk of more than 5- to 10-fold seem to be suitable for enrollment in a surveillance program for prevention or early detection of pancreatic cancer. The aim of such a program is to reduce pancreatic cancer mortality through early or preemptive surgery. Considering the risk associated with pancreatic surgery, the concept of preemptive surgery cannot consist of a prophylactic removal of the pancreas in high-risk healthy individuals, but must instead aim at treating precancerous lesions such as intraductal papillary mucinous neoplasms or pancreatic intraepithelial neoplasms, or early cancer. Currently, results from clinical trials do not convincingly demonstrate the efficacy of this approach in terms of identification of precancerous lesions, nor do they define the outcome of the surgical treatment of these lesions. For this reason, surveillance programs for individuals at risk of pancreatic cancer are thus far generally limited to the setting of a clinical trial. However, the acquisition of a deeper understanding of this complex area, together with the increasing request for screening and treatment by individuals at risk, will usher pancreatologists into a new era of preemptive pancreatic surgery. Along with the growing demand to treat individuals with precancerous lesions, the need for low-risk investigation, low-morbidity operation and a minimally invasive approach becomes increasingly pressing. All of these considerations are reasons for preemptive pancreatic surgery programs to be undertaken in specialized centers only.

Predicting the Risk for Acute Type B Aortic Dissection in Hypertensive Patients Using Anatomic Variables

This study sought to identify possible anatomic predictors of acute type B aortic dissection (AAD) in hypertensive patients using multidetector computed tomography angiography (CTA). Although hypertension remains one of the most significant risk factors for AAD development, it is unlikely to be the only risk factor for AAD. Few studies have assessed anatomical predictors of AAD development. CTA of normotensive patients without AAD (group 1, n = 35), hypertensive patients without AAD (group 2, n = 37), and hypertensive patients with AAD (group 3, n = 37) were compared. The length, diameter, volume, and tortuosity of the aorta as well as arch vessel angulation were measured for each patient and normalized to group 1 averages. Stepwise logistic regression identified significant anatomical associations; the model was validated based on 1,000 bootstrapped samples. The demographics of the groups were similar. The length of the proximal and entire aorta, the diameters in the proximal ascending aorta and aortic arch, and the aortic volumes were all greater (p < 0.0001, p = 0.0064 for ascending aortic diameter) in group 3 than in groups 1 and 2, as was entire aortic tortuosity (p < 0.0001). An AAD risk model was developed based on aortic arch diameter, length from the aortic root to the iliac bifurcation, and angulation of the brachiocephalic artery origin from the aorta. The bootstrap estimate of the area under the receiver operating curve was 0.974. Enlargement of the ascending aorta and aortic arch and increased aortic tortuosity reflect an aortopathy which enhances the probability of AAD. A model based on 3 anatomical variables demonstrates significant associations with AAD: it may allow identification by aortic imaging of the hypertensive patient most at risk, and permit implementation of aggressive medical management and consideration of pre-emptive surgery to prevent dissection.

Preneoplastic conditions underlying bile duct cancer.

Malignancies arising from the biliary tract can arise from the epithelial lining of the biliary tract and surrounding tissues. Conditions that predispose to malignancy as well as preneoplastic changes in biliary tract epithelia have been identified. In this overview, we discuss preneoplastic conditions of the biliary tract and emphasize their clinical relevance. Chronic biliary tract inflammation predisposes to cancer in the biliary tract. Biliary tract carcinogenesis involves a multistep process as a consequence of chronic biliary epithelial injury or inflammation. Reminiscent of other gastrointestinal epithelial malignancies such as gastric, colon, and pancreatic cancer, biliary tract cancers may evolve via multistep progression from epithelial hyperplasia and dysplasia to malignant transformation. The potential role of initiating cells is also becoming recognized. In spite of improved risk factor recognition, and advances in diagnostic tools, the early diagnosis of pre-malignant or malignant biliary tract conditions is extremely challenging, and there is a paucity of evidence on which to base their management. As a result, the role of pre-emptive surgery remains largely undefined.