Optimal Surveillance Strategy Research Articles

The Shwachman-Diamond Syndrome Registry: Hematologic Complications

▪The Shwachman-Diamond Syndrome Registry (SDSR) was established in December 2008 with the goal of understanding the natural history and biology of SDS to improve the lives of people with SDS. The SDSR has enrolled 220 patients with biallelic SBDS mutations or SDS-Like features. Longitudinal data has been collected for 176 patients with a median duration of follow-up of 10.7 (0.3-52.8) years. Biallelic SBDS mutations were noted in 117 patients, and biallelic DNAJC21 mutations in one patient. Sequencing of genetically undefined cases did not identify EFL1 or SRP54 mutations. Ongoing characterization of SBDS mutation-negative individuals has identified subgroups of clinically defined SDS individuals, as well as a more heterogenous subgroup with features of SDS but who do not meet classic diagnostic criteria. Clinical characteristics and outcomes of patients with biallelic SBDS mutations were examined. AML developed in 5 patients and MDS in 11 patients at a median age 37.9 years (range, 19.5-47.3) and 10.7 years (range, 1-45) respectively. No solid tumors were diagnosed. 21 individuals have undergone stem cell transplantation. Overall survival was 91% in the 10 years since registry establishment, with deaths mainly caused by myelodysplasia (MDS) (n=3) and acute myeloid leukemia (AML) (n=4). One individual with MDS died of hepatic failure unrelated to MDS.Hematologic parameters, trends over time, and clinical correlations were examined.. Cytopenias were almost universal (98.8%) and often intermittent, with neutropenia the most frequent in 98.8%, anemia in 16.5% and thrombocytopenia in 45.3%. Bone marrow evaluations were available in 98, with 88.2% demonstrating marrow hypoplasia. Notable, marrow hypoplasia was progressive, with average marrow cellularity of 74% in patients <1 year of age (n=13), 45% in marrows of children 1-19 years of age (n=277), and 38% in marrows of adults 19-43 years of age (n=38). Cases with discordance between marrow cellularity and cytopenias were noted, so a systematic analysis of the patterns of marrow cellularity and blood counts is ongoing. Marrow dysmorphologies were common and present in in 40.9%, 49.5%, and 28% of the erythroid, myeloid and megakaryocyte lineages respectively, highlighting the need for review from pathologists experienced in the baseline dysmorphologies common in SDS. Marrow cytogenetic data were available for 89 patients of whom 30 (33%) developed clonal abnormalities diagnosed at median age of 8.67 years (range, 0.3-38.9). The most common clonal abnormalities were iso(7q) (n=4) and del(20q) (n=13). Blood count patterns associated with these clonal abnormalities were variable. Notably, iso7q clones were transient while the majority of del20q clones were persistent. One patient with a history of an iso(7q) clone and one with a del(20q) clone progressed to MDS.There is a paucity of evidence to guide optimal surveillance strategies for leukemia predisposition syndromes. The SDSR revealed wide variation in clinical practice amongst local hematologists including: 1) no surveillance for well-appearing patients, 2) intermittent blood counts, or 3) bone marrow exams of variable frequency with variable testing of cytogenetics and FISH. Some patients were not followed by hematology because they looked well until they presented with AML. In one illustrative case, a teenage patient with a transient iso7q clone had improving hemoglobin, platelet counts, absolute neutrophil counts, and reduction in red cell macrocytosis over the year prior to diagnosis of MDS. Additional clinical and laboratory studies are underway to provide evidence-based guidelines and to develop more sensitive tests for optimal surveillance of patients with predisposition to myeloid malignancies. DisclosuresMyers:Novartis: Membership on an entity's Board of Directors or advisory committees; Bellicum Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees.

Incidence of tuberculosis and the influence of surveillance strategy on tuberculosis case-finding and all-cause mortality: a cluster randomised trial in Indian neonates vaccinated with BCG

IntroductionAccurate tuberculosis (TB) incidence and optimal surveillance strategies are pertinent to TB vaccine trial design. Infants are a targeted population for new TB vaccines, but data from India, with the...

Portomesenteric venous complications following pancreatoduodenectomy: incidence and risk factors

Introduction: Risk factors for and optimal management of portomesenteric venous complications after pancreatoduodenectomy (PD) are not well-defined. Methods: Single-center, retrospective review of patients with PD (2016–2017). Clinical data, operative details and postoperative portomesenteric venous complications were recorded based on data abstraction and independent radiologic re-review. Results: Of 105 patients, the mean age was 64 years. Neoadjuvant therapy was received in 51 (48.6%) patients and included chemoradiation in 42. PD with portomesenteric vein resection occurred in 24 (23%) and arterial resection in 5 (5%). Postoperative fluid collections were identified in 46 (49%) patients with 12.5% confirmed as pancreatic fistula. On postoperative surveillance, portal vein (PV) or superior mesenteric vein (SMV) narrowing was present in 18 (19%) and 38 (40%) of patients respectively. Resolution occurred without intervention in 23 (41%) patients whereas venous stenting was performed in 8 (14%). PV narrowing and thrombosis were associated with presence of a postoperative fluid collection (p < 0.01, p < 0.03). SMV narrowing was associated with postoperative fluid collection (p < 0.001), neoadjuvant radiation (p < 0.02) and vein resection (p < 0.0001). Stenting of the PV and SMV were associated with vein resection (p < 0.01 and p < 0.05). Conclusion: These preliminary data suggest that neoadjuvant radiation, vein resection and postoperative fluid collection may be risk factors for portomesenteric venous complications following PD. Validation of independent risk factors may allow development of a clinical risk score to assess optimal surveillance and treatment strategies.

The diagnostic performance of CT versus FDG PET-CT for the detection of recurrent pancreatic cancer: a systematic review and meta-analysis

ObjectivesRadiologic surveillance after resection of pancreatic ductal adenocarcinoma (PDAC) can provide information on the extent and location of disease recurrence. This systematic review and meta-analysis aims to give an overview of the literature on the diagnostic performance of different imaging modalities for the detection of recurrent disease after surgery for PDAC. MethodsA systematic search was performed in PubMed, EMBASE and Cochrane Library up to 20 December 2017. All studies reporting on the diagnostic value of imaging modalities for the detection of local and/or distant disease recurrence during follow-up after resection of PDAC were eligible. Both histologic confirmation of recurrent PDAC and clinical confirmation by disease progression on follow-up imaging were considered as suitable reference standard. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool was used for critical appraisal of methodological quality. Diagnostic accuracy data were extracted or calculated and presented in forest plots. A bivariate random-effects model was used to calculate pooled estimates of sensitivity and specificity. ResultsA total of seven retrospective studies with 333 relevant patients were ultimately eligible for data extraction. Overall, the methodological quality of the included studies was acceptable. All seven articles described test results of contrast-enhanced CT, whilst five and three articles reported outcomes on diagnostic accuracy of FDG PET-CT and FDG PET-CT combined with contrast-enhanced CT, respectively. For CT, pooled estimates for sensitivity were 0.70 (95% CI 0.61–0.78) and for specificity 0.80 (95% CI 0.69–0.88). For FDG PET-CT, pooled estimates for sensitivity and specificity were 0.88 (95% CI 0.81–0.93) and 0.89 (95% CI 0.80–0.94), respectively. For FDG PET-CT in combination with contrast-enhanced CT, pooled estimates for sensitivity were 0.95 (95% CI 0.88–0.98) and for specificity 0.81 (95% CI 0.63–0.92). ConclusionsAccording to the current literature, post-operative CT has a moderate diagnostic accuracy in the detection of recurrent disease. FDG PET-CT imaging could be of additional value when disease recurrence is suspected despite negative or equivocal CT findings. Nevertheless, evidence supporting radiologic surveillance after resection of PDAC is limited. Future prospective studies are needed to optimize surveillance strategies after resection of pancreatic cancer.

Significance of Negative Posttreatment 18-FDG PET/CT Imaging in Patients With p16/HPV-Positive Oropharyngeal Cancer

Patients with p16/human papilloma virus (HPV)-associated oropharyngeal squamous cell carcinoma have a favorable outcome after treatment. In this group of patients who could have a long life expectancy, the optimal surveillance strategy and modality is not well established. We aim to determine the ability of a negative postradiation positron emission tomography (PET)/computed tomography scan to predict the risk of subsequent relapse in these patients. A retrospective analysis of patients with p16/HPV-associated oropharyngeal squamous cell carcinoma who completed definitive (chemo)radiation therapy and had a posttreatment PET/computed tomography scan from 2006 to 2013 was performed. Patient, tumor, and treatment characteristics and clinical outcomes were recorded. Tumors were considered HPV/p16 positive if either HPV (by in situ hybridization) or p16 (by immunohistochemistry) was positive. Disease-free survival and overall survival rates were estimated using the Kaplan-Meier method. In our study, 327 patients were evaluated. The median age was 57years. The most common primary sites were base of tongue (50%) and tonsil (48%). Of the patients evaluated, 291 (89%) had a negative posttreatment PET scan. For these 291 patients who had a complete metabolic response after treatment, the 5-year disease-free survival and overall survival rates were 91% and 89%, respectively. The median time to development of recurrence was 16months. Of the 291 patients, 24 patients (8%) had disease recurrence; 13 recurrences were locoregional, and 13 were distant. Eleven (4%) patients with recurrence had further surgery or radiation, and 8 patients (3%) were without disease as of the last follow-up. Patients who achieve a complete metabolic response on posttreatment PET imaging have an excellent prognosis, and the risk of developing a recurrence in the future is very low. Therefore, a more cost effective surveillance program should be considered for this subgroup of patients.

Distinctive facies, macrocephaly, and developmental delay are signs of a PTEN mutation in childhood

BackgroundGermline mutations of the PTEN gene are responsible for several PTEN hamartoma tumor syndromes. They are also implicated as a cause of macrocephaly and mild to severe developmental delay, regardless of the presence or absence of hamartomas in childhood. Nevertheless, because of limited information, the clinical features present during childhood in patients with a PTEN mutation are yet to be elucidated. MethodsPTEN mutations were investigated by multiplex targeted sequencing of genomic DNA from 33 children with increased head circumference (>+2 SD) and developmental delay. The clinical features of all the patients with a PTEN mutation were abstracted by dysmorphologists. ResultsWe have identified six children with a PTEN mutation. Clinical dissection of these six patients, in addition to patient reports in the literature, revealed distinctive facial features that included frontal bossing, dolichocephaly, horizontal eyebrows, and a depressed nasal bridge. Macrocephaly (+3.2 to +6.0 SD) was noticeable compared to their height (−0.8 to +2.1 SD), and the difference in the SD value of head circumference and height was more than 3 SD in all patients. ConclusionThe presence of distinctive facies, extreme macrocephaly with normal to mildly high stature, and developmental delay may be useful for identifying patients with a PTEN mutation in childhood. Early identification of patients with a PTEN mutation would help uncover the natural course of tumor development in this group of individuals who have a possible predisposition to cancer, and be important for the development of an optimal surveillance strategy.

Arterial Thrombosis in Patients with Cancer.

Cancer is a common cause of morbidity and mortality in the USA. While the association between venous thrombosis and malignancy is well established, arterial thrombosis has more recently been recognized as a serious complication of cancer and certain chemotherapeutic agents. This review aims to summarize the most recent literature regarding the incidence and risk factors for cancer-related arterial thrombosis, understand the pathophysiologic mechanisms of thrombosis, and highlight the specific diagnostic and treatment considerations relevant to cancer patients. Based on a recent study looking at the Surveillance, Epidemiology, and End Results (SEER) database, the incidence of arterial thromboembolic events (ATEs) in patients with cancer at 6months is 4.7%; the presence of an ATE is predictive of worse outcomes. Certain drugs such as platinum-based agents, vascular endothelial growth factor inhibitors, tyrosine kinase inhibitors, and taxanes have been associated with high rates of ATEs. Increased platelet reactivity appears crucial to development of arterial thrombosis in cancer patients. Cancer patients have an increased risk of arterial thrombosis that is likely due to both a cancer-associated procoagulant state as well as the adverse effects of certain chemotherapeutic agents. Treatment of arterial thromboembolism in cancer patients typically requires a multidisciplinary approach in part due to high rates of thrombocytopenia and stent thrombosis in the setting of percutaneous interventions. More studies are needed to investigate optimal prophylaxis, surveillance strategies, and treatments of cancer-related arterial thromboembolic disease.

FDG-PET/CT for treatment response assessment in head and neck squamous cell carcinoma: a systematic review and meta-analysis of diagnostic performance.

18-fluorodeoxyglucose positron emission tomography combined with computed tomography (FDG-PET/CT) is increasingly used to evaluate treatment response in head and neck squamous cell carcinoma (HNSCC). This analysis assessed the diagnostic value of FDG-PET/CT in detecting nodal disease within 6months after treatment, considering patient and disease characteristics. A systematic review was performed using the MEDLINE and Web of Knowledge databases. The results were pooled using a bivariate random effects model of the sensitivity and specificity. Out of 22 identified studies, a meta-analysis of 20 studies (1293 patients) was performed. The pooled estimates of sensitivity, specificity and diagnostic odds ratio (with 95% CI) were 85% (76-91%), 93% (89-96%) and 76 (35-165), respectively. With the prevalence set at 10%, the positive and negative predictive values were 58% and 98%. There was significant heterogeneity between the trials (p< 0.001). HPV positive tumors were associated with lower sensitivity (75% vs 89%; p= 0.01) and specificity (87% vs 95%; p< 0.005). FDG-PET/CT within 6months after (chemo)radiotherapy in HNSCC patients is a reliable method for ruling out residual/recurrent nodal disease and obviates the need for therapeutic intervention. However, FDG-PET/CT may be less reliable in HPV positive tumors and the optimal surveillance strategy remains to be determined.

Sustaining visceral leishmaniasis elimination in Bangladesh - Could a policy brief help?

Bangladesh has made significant progress towards elimination of visceral leishmaniasis, and is on track to achieve its target of less than one case per 10,000 inhabitants in each subdistrict in 2017. As the incidence of disease falls, it is likely that the political capital and financial resources dedicated towards the elimination of visceral leishmaniasis may decrease, raising the prospect of disease resurgence. Policy memos may play a crucial role during the transition of the elimination plan from the ‘attack’ to the ‘consolidation’ and ‘maintenance’ phases, highlighting key stakeholders and areas where ongoing investment is crucial. An example of a policy brief is outlined in this paper. The background to the current elimination efforts is highlighted, with emphasis on remaining uncertainties including the impact of disease reservoirs and sustainable surveillance strategies. A stakeholder map is provided outlining the current and projected future activities of key bodies. Identification of key stakeholders subsequently frames the discussion of three key policy recommendations in the Bangladeshi context for the transition to the consolidation and maintenance phases of the elimination program. Recommendations include determining optimal vector control and surveillance strategies, shifting the emphasis towards horizontal integration of disease programs, and prioritising remaining research questions with a focus on operational and technical capacity. Achieving elimination is as much a political as a scientific question. Integrating the discussion of key stakeholders with policy priorities and the research agenda provides a novel insight into potential pathways forwards in the elimination of visceral leishmaniasis in Bangladesh and in the rest of the Indian subcontinent.

Incidental Septostomy after Laser Surgery for Twin-Twin Transfusion Syndrome: Perinatal Outcomes and Antenatal Management

Introduction: Incidental septostomy, or inadvertent perforation of the twins’ dividing membranes, can create a functional monoamniotic twin pregnancy. Our aim was to describe the perinatal outcomes and antenatal management of patients with incidental septostomy after laser surgery for twin-twin transfusion syndrome (TTTS). Materials and Methods: Monochorionic diamniotic multiple gestations with a gestational age (GA) between 16 and 26 weeks that underwent laser surgery from March 2006 to December 2015 were studied retrospectively. Perinatal outcomes were compared for patients with and without an incidental septostomy. A subgroup analysis was performed to evaluate antenatal management. Results: Of 532 TTTS patients who underwent laser surgery, incidental septostomy occurred in 34 (6.4%). Compared to all others, patients with a septostomy had an earlier median (range) GA at delivery (30.8 [18.6–37.9] vs. 34.0 [19.3–40.4] weeks, p < 0.0001) and lower 30-day survival of at least one twin (85.3 vs. 94.6%, p = 0.0452). We found no evidence that inpatient fetal surveillance was protective. Discussion: Incidental septostomy in TTTS patients treated via laser surgery appeared to be associated with lower GA at delivery and perinatal survival of at least one twin. Further study is required to determine the optimal antenatal surveillance strategy.

Radiation-Induced Cardiovascular Disease: A Clinical Perspective.

Cancer survival has improved dramatically, and this has led to the manifestation of late side effects of multimodality therapy. Radiation (RT) to the thoracic malignancies results in unintentional irradiation of the cardiac chambers. RT-induced microvascular ischemia leads to disruption of capillary endothelial framework, and injury to differentiated myocytes results in deposition of collagen and fibrosis. Coexistence of risk factors of metabolic syndrome and preexisting atherosclerosis in addition to RT exposure results in accelerated occurrence of major coronary events. Hence, it becomes pertinent to understand the underlying pathophysiology and clinical manifestations of RT-induced cardiovascular disease to devise optimal preventive and surveillance strategies.

Higher Rates of Proximal Sessile Serrated Adenomas Among Whites Compared to Asians, Hispanics and Blacks

Introduction: Surveillance, Epidemiology, End Results (SEER) data in the United States reveal that Whites rank third behind Blacks and American Indian/Alaska Natives for incidence and mortality from colorectal cancer. Sessile Serrated Adenomas (SSAs) have been proposed to play a role in the development of interval colorectal cancer; however, limited studies have assessed the prevalence of SSAs among Whites, Asians, Hispanics and Blacks. Our objective was to compare the prevalence of SSAs between Whites, Asians, Hispanics and Blacks using sessile serrated adenoma detection rate (SSADR) as a surrogate of prevalence. Methods: Colonoscopy quality data was collected prospectively at our single tertiary referral center from June 2012 to May 2017 using Qualoscopy (Docbot, Inc.). We included all diagnostic, screening and surveillance colonoscopies in Whites, Asians, Hispanics and Blacks over 40 years of age. Whites were compared to Asians, Hispanics and Blacks for detection of polyps (PDR), adenomas (ADR) and sessile serrated adenoma (SSADR) (Table 2). Subgroup analysis included colon location. Baseline characteristics included gender, age, BMI, bowel prep scores, bowel prep liters, total procedure time and cecal intubation rates (Table 1). Significance was determined by a two-tailed Fischer's exact test and T-test.Table: Table. Average Polyp Detection RatesTable: Table. Baseline CharacteristicsResults: 6085 colonoscopies met our inclusion criteria, of which 4448 were performed in Whites, 989 in Asians, 481 in Hispanics and 167 in Blacks. Overall, Whites had statistically higher rates of proximal sessile serrated adenomas (9.10%) compared to Asians (7.10%), Hispanics (3.70%) and Blacks (4.20%). Compared to Hispanics, Whites had significantly higher PDRs, ADRs, SSADRs within the entire colon and right colon and higher PDRs and ADRs within the left colon. Compared to Asians, Whites had significantly higher SSADRs within the entire colon but significantly lower ADRs within the left colon. Conclusion: Our data demonstrate significant racial differences in detections rates of polyps, adenomas and sessile serrated adenomas. Whites have higher proximal SSADRs compared to Asians, Hispanics and Blacks. Although Blacks have a higher incidence and mortality from colorectal cancer compared to Whites, we were unable to demonstrate increased prevalence of precancerous polyps in this group, perhaps due to the small sample size of our Black cohort. Larger studies are needed to verify our findings, which have significance relative to optimal screening and surveillance strategies.

The Rate of Cervical Length Shortening in the Management of Vasa Previa.

There is no consensus about the optimal surveillance strategy in women with a diagnosis of vasa previa. The aim of this study was to evaluate the role of the rate of change in cervical length measurements in the management of singleton pregnancies with a diagnosis of vasa previa. We performed a retrospective case-control study of our databases for pregnancies with a prenatal diagnosis of vasa previa that were followed with transvaginal sonography for cervical length and evaluated the impact of the changes in cervical length on the need for emergency cesarean delivery. The cohort included 29 singleton pregnancies with a prenatal diagnosis of vasa previa in the second trimester. There were 14 and 15 pregnancies that underwent elective and emergency cesarean delivery, respectively. The rate of cervical length shortening was significantly slower for women with elective compared to emergency cesarean delivery (median [range], 0.7 [0.1-2.0] versus 1.5 [0.25-3.0] mm/wk; P = .011). For each additional millimeter-per-week decrease in cervical length, the odds of emergency cesarean delivery increased by 6.50 (95% confidence interval, 1.02-41.20). The receiver operating characteristic curve for the rate of cervical length shortening in the prediction of emergency cesarean delivery yielded an area under the curve of 0.85 (95% confidence interval, 0.69-0.99). Our findings indicate an association between the rate of cervical length shortening and the risk of emergency cesarean delivery in pregnancies with a diagnosis of vasa previa in the second trimester. Further multicentric studies are required to validate our data prospectively and, in particular, the role of serial cervical length measurements in determining the optimal delivery time for individual cases.

Optimal surveillance strategies for bovine tuberculosis in a low-prevalence country

Bovine tuberculosis (bTB) is a chronic disease of cattle that is difficult to control and eradicate in part due to the costly nature of surveillance and poor sensitivity of diagnostic tests. Like many countries, bTB prevalence in Uruguay has gradually declined to low levels due to intensive surveillance and control efforts over the past decades. In low prevalence settings, broad-based surveillance strategies based on routine testing may not be the most cost-effective way for controlling between-farm bTB transmission, while targeted surveillance aimed at high-risk farms may be more efficient for this purpose. To investigate the efficacy of targeted surveillance, we developed an integrated within- and between-farm bTB transmission model utilizing data from Uruguay’s comprehensive animal movement database. A genetic algorithm was used to fit uncertain parameter values, such as the animal-level sensitivity of skin testing and slaughter inspection, to observed bTB epidemiological data. Of ten alternative surveillance strategies evaluated, a strategy based on eliminating testing in low-risk farms resulted in a 40% reduction in sampling effort without increasing bTB incidence. These results can inform the design of more cost-effective surveillance programs to detect and control bTB in Uruguay and other countries with low bTB prevalence.

Bio-economic optimisation of surveillance to confirm broadscale eradications of invasive pests and diseases

Although pest eradications from islands have been successful and impart biodiversity benefits, eradications at regional/national scales are more challenging. Such broadscale eradications incur high repeated costs (e.g. control and surveillance effort) because the entire area cannot be treated at one time, and a progressive ‘treat-evaluate-move on’ approach must be employed. We describe a two-stage model to analyse surveillance data for assessing progress and declaring success of broadscale eradications, and to identify optimal cost-efficient surveillance strategies. Stage I modelling coincides or follows population control within a subset area or management zone (MZ). Surveillance data are analysed to quantify the probability of freedom for a treated MZ (i.e. local eradication), which is used to inform an operational decision to reallocate resources to other MZs, and progress across the region. Importantly, freedom declared individually in all MZs is not necessarily equivalent to a high probability of eradication over the broadscale area, because each MZ will have a probability of being erroneously declared free. After a MZ has been operationally declared free, Stage II surveillance commences to detect MZ-level failures, and to estimate the broadscale surveillance sensitivity and a corresponding probability of eradication. We developed a computer algorithm to identify cost-optimal Stage I and II surveillance strategies for a hypothetical large area. We assessed the following: (1) the balance between local surveillance intensity and spatial coverage; (2) the number of years to declare success in Stages I and II; (3) the stopping probability of freedom (Stage I); and (4) the optimal strategy given variation in the starting-over cost, should a MZ be erroneously declared free. This two-stage approach provides an objective basis for decision-making in wildlife pest/disease eradication, and guidance for implementing optimal bio-economic surveillance strategies.

Influence of a patient transfer network of US inpatient facilities on the incidence of nosocomial infections

Antibiotic-resistant bacterial infections are a substantial source of morbidity and mortality and have a common reservoir in inpatient settings. Transferring patients between facilities could be a mechanism for the spread of these infections. We wanted to assess whether a network of hospitals, linked by inpatient transfers, contributes to the spread of nosocomial infections and investigate how network structure may be leveraged to design efficient surveillance systems. We construct a network defined by the transfer of Medicare patients across US inpatient facilities using a 100% sample of inpatient discharge claims from 2006–2007. We show the association between network structure and C. difficile incidence, with a 1% increase in a facility’s C. difficile incidence being associated with a 0.53% increase in C. difficile incidence of neighboring facilities. Finally, we used network science methods to determine the facilities to monitor to maximize surveillance efficiency. An optimal surveillance strategy for selecting “sensor” hospitals, based on their network position, detects 80% of the C. difficile infections using only 2% of hospitals as sensors. Selecting a small fraction of facilities as “sensors” could be a cost-effective mechanism to monitor emerging nosocomial infections.

Optimal Surveillance Strategies After Surgery for Renal Cell Carcinoma.

One in 5 patients who undergo surgical resection for clinically localized renal cell carcinoma (RCC) develop local and/or distant recurrences which, when detected early, may be amenable to salvage local and systemic therapies. When considering that approximately half of these recurrences will occur during the first 2 years, a clear rationale exists for optimizing surveillance strategies after surgery. Although there is a notable dearth of high-quality data on this subject, clinical principles can guide clinicians as they attempt to balance the burden of surveillance strategies with potential clinical benefit. The objective of this review is to summarize the evidence regarding optimal surveillance protocols after surgery for RCC. We provide an overview of the rationale supporting surveillance after surgery, a summary of the American Urological Association and NCCN guidelines, reasons against routine long-term surveillance, surveillance costs, and ancillary issues, such as the utility of bone scan, PET/CT scan, and surveillance after thermoablation.

Cost effectiveness of surveillance for distant recurrence in extremity soft tissue sarcoma.

11021 Background: Optimal surveillance strategies for extremity soft tissue sarcoma (STS) are unknown. We performed a cost-effectiveness analysis of competing imaging modalities performed at National Cancer Comprehensive Network guideline-specified intervals. Methods: We developed a Markov model simulating lifetime outcomes for 54-year-old patients after definitive treatment for Stage II-III extremity STS using four surveillance strategies: watchful waiting (WW), chest x-ray (CXR), chest computed tomography (CCT) and positron emission tomography-computed tomography (PET/CT) performed every 3-6 months for the first 3 years, every 6 months until year 5, and then annually. We used probabilities, utilities and costs extracted from the literature and Medicare claims to determine incremental cost-effectiveness ratios (ICER). Results: While the model showed that CCT is the most effective strategy, CXR is the most cost-effective strategy at a societal willing-to-pay (WTP) of $100,000/quality-adjusted life year (QALY). The ICER is $14,306/QALY for CXR versus $117,683/QALY for CCT while PET/CT is never cost effective (Table). Sensitivity analyses demonstrated CCT becomes the preferred imaging modality as the lifetime risk of DR increases beyond 38% or as the societal WTP increases beyond $130,000/QALY. Conclusions: Optimal DR surveillance imaging for Stage II-III extremity STS should be individualized based on patients’ risks for DR. CXR, or CCT at more protracted intervals, may be preferred for lower risk patients (i.e. DR risk less than 38%), whereas CCT may be preferred for higher risk patients (i.e. DR risk greater than 38%). These findings can help refine guidelines to reduce resource overutilization during surveillance of sarcoma patients. [Table: see text]

Retrospective study of the influence of HPV persistence on outcomes among women with high-risk HPV infections and negative cytology.

To evaluate the outcomes of women diagnosed with high-risk HPV without cytology evidence of cervical dysplasia. The present retrospective observational study enrolled consecutive women aged at least 18years diagnosed with high-risk HPV types with negative cytology results at the National Cancer Institute, Milan, Italy, between January 1, 2005, and December 31, 2015. The development of cervical intraepithelial neoplasia (CIN) was assessed. There were 212 patients with high-risk HPV infections with negative cytology included in the analysis. After a mean±SD follow-up period of 48±33months, 65 (30.7%) and 26 (12.3%) patients had developed cytologic or histologic cervical dysplasia (low-grade squamous intraepithelial lesion [LSIL]/CIN1+) and high-grade cervical dysplasia (CIN2+), respectively. No patients had invasive cancer. No correlations were observed between type-specific HPV infections and LSIL/CIN1+ and CIN2+. HPV persistence correlated with both LSIL/CIN1+ (P<0.001) and CIN2+ (P<0.001) in univariate analyses; a 6-month increase in HPV persistence was associated with increased risk of developing LSIL/CIN1+ (P=0.010) and CIN2+ (P=0.012) in multivariate analyses. Regardless of cytology findings, patients diagnosed with high-risk HPV types should receive strict colposcopy follow-up, particularly with persistent HPV infections. Further prospective studies are needed to defined optimal surveillance strategies for these patients.

Modeling the spread of avian influenza viruses in aquatic reservoirs: A novel hydrodynamic approach applied to the Rhône delta (southern France)

Wild aquatic birds represent a natural reservoir of avian influenza viruses (AIV) that can be spread to poultry. AIV epizootics were associated with huge economic impacts during the last decades and are still of major concern. Within aquatic bird populations AIV are transmitted either by direct contact or through the ingestion of water that has been contaminated by infected individuals. This second route involving environmental transmission is of utmost importance in AIV dynamics, yet it has received far less attention than direct bird-to-bird contamination. Our objective was to combine a hydrodynamic model with data on mallard abundance and AIV infection rate within the population, so as to characterize virus dissemination within a complex wetland network. We chose the Vaccarès hydrosystem as a wetland model since it represents a large part of the Camargue region, which is a major wintering site for a large diversity of aquatic birds including AIV hosts. We aimed to identify the environmental parameters that drive AIV dynamics within this system and the spatio-temporal pattern of dispersion and persistence of viruses. Our results show that in a complex hydrosystem we can expect a great heterogeneity in AIV risk among wetlands. Our simulations underline how a simple “homogeneous box” approach could in the case of deltaic ecosystems minimize the expected risk by diluting it in the whole system. Moreover, such undermining of the risk perception could affect the predictions relative to risk duration. We present a new approach to identify hotspots of virus concentrations within deltaic areas that could take advantage of the duck count data, AIV surveys and hydrodynamic models that may already be available in several major duck wintering areas comprised of complex hydrosystems, such as the large European deltas. Our method could be of particular interest to optimize surveillance strategies in the current context of highly pathogenic AIV diffusion within wild bird populations.