Elisabeth U Dexter

Roswell Park Cancer Institute, Buffalo, New York, United States

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Publications (37)120.02 Total impact

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    ABSTRACT: Background:It is unclear whether thoracoscopic (VATS) pneumonectomy improves outcomes compared to open approaches. Methods:107 consecutive pneumonectomies performed at an experienced center from 1/2002 to 12/2012 were studied retrospectively. Forty cases were open, while 50 successful VATS and 17 conversions were combined (intent-to-treat analysis, ITT). Results:The VATS cohort had more preoperative comorbidities (3 vs. 2, p=0.003), females (57 vs. 30% p=0.009) and older ages (65 vs. 63 years, p=0.07). While advanced clinical stage was less for VATS (26 vs. 50% Stage III, p=0.035), final pathologic staging was similar (25 vs. 38%, p=0.77). Pursuing a VATS approach yielded similar complications (2 vs. 2, median, p=0.73) with no catastrophic intraoperative events like bleeding. Successful VATS pneumonectomy rates rose from 50% to 82% by the second half of the series (p<0.001). Completion pneumonectomy cases (13.4% VATS/7.5% Open) had similar outcomes. Having similar initial discomforts as open, more VATS patients were pain-free at 1 year (53% vs. 19%, p=0.03). Conversions resulted in longer ICU stays (4 vs. 2 days, p=0.01). Advanced clinical stage (III-IV) ITT VATS had longer median OS (42 vs. 13 months, log-rank p =0.042). Successful VATS cases with early pathological stage (0-II) had a median OS of 80 months versus 16 for converted and 28 for open (log rank=0.083). Conclusions:Attempting thoracoscopic pneumonectomy at an experienced center appears safe but does not yield the early pain/complication reductions observed for VATS lobectomy. There may be long-term pain/survival advantages for certain stages that warrant further study and refinement of this approach.
    Chest 06/2014; · 7.13 Impact Factor
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    ABSTRACT: Tobacco assessment and cessation support are not routinely included in cancer care. An automated tobacco assessment and cessation program was developed to increase the delivery of tobacco cessation support for cancer patients. A structured tobacco assessment was incorporated into the electronic health record at Roswell Park Cancer Institute to identify tobacco use in cancer patients at diagnosis and during follow-up. All patients who reported tobacco use within the past 30 days were automatically referred to a dedicated cessation program that provided cessation counseling. Data were analyzed for referral accuracy and interest in cessation support. Between October 2010 and December 2012, 11,868 patients were screened for tobacco use, and 2765 were identified as tobacco users and were referred to the cessation service. In referred patients, 1381 of those patients received only a mailed invitation to contact the cessation service, and 1384 received a mailing as well as telephone contact attempts from the cessation service. In the 1126 (81.4%) patients contacted by telephone, 51 (4.5%) reported no tobacco use within the past 30 days, 35 (3.1%) were medically unable to participate, and 30 (2.7%) declined participation. Of the 1381 patients who received only a mailed invitation, 16 (1.2%) contacted the cessation program for assistance. Three questions at initial consult and follow-up generated over 98% of referrals. Tobacco assessment frequency every 4 weeks delayed referral in < 1% of patients. An automated electronic health record-based tobacco assessment and cessation referral program can identify substantial numbers of smokers who are receptive to enrollment in a cessation support service. Cancer 2014;120:562-569. © 2013 American Cancer Society.
    Cancer 02/2014; 120(4):562-9. · 5.20 Impact Factor
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    ABSTRACT: Lymph node staging provides critical information in patients with non-small cell lung cancer (NSCLC). Lymphangiogenesis may be an important contributor to the pathophysiology of lymphatic metastases. We hypothesized that the presence of lymph node micrometastases positively correlates with vascular endothelial growth factors (VEGFs) A, C, and D as well as VEGF-receptor-3 (lymphangiogenic factors) expression in lymph nodes. Forty patients with NSCLC underwent preoperative positron emission tomography-computed tomography and mediastinoscopy. Real-time polymerase chain reaction (RT-PCR) assays for messenger RNA expression of epithelial markers (ie, cytokeratin 7; carcinoembryonic antigen-related cell adhesion molecule 5; and palate, lung, and nasal epithelium carcinoma-associated protein) were performed in selected fluorodeoxyglucose-avid lymph nodes. VEGF-A, VEGF-C, VEGF-D, and VEGF receptor-3 expression levels were measured in primary tumors and lymph nodes. Wilcoxon rank sum test was run for the association between the RT-PCR epithelial marker levels and VEGF expression levels in the lymph nodes. RT-PCR for cytokeratin 7; carcinoembryonic antigen-related cell adhesion molecule 5; or palate, lung, and nasal epithelium carcinoma-associated protein indicated lymph node micrometastatic disease in 19 of 35 patients (54%). There was a high correlation between detection of micrometastases and VEGF-A, VEGF-C, VEGF-D, or VEGF receptor-3 expression levels in lymph nodes. Median follow-up was 12.6 months. RT-PCR analysis of fluorodeoxyglucose-avid lymph nodes results in up-staging a patient's cancer. Micrometastases correlate with the expression of VEGF in lymph nodes in patients with NSCLC. This may reflect the role of lymphangiogenesis in promoting metastases.
    The Journal of thoracic and cardiovascular surgery 03/2013; 145(3):702-8. · 3.41 Impact Factor
  • Journal of Surgical Research 02/2013; 179(2):186. · 2.12 Impact Factor
  • Journal of thoracic and cardiovascular surgery. 01/2013; 145(3):702-708.
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    ABSTRACT: BACKGROUND: Since the randomized, controlled study that favored lobectomy for resection of stage I non-small cell lung cancers (NSCLCs) by the Lung Cancer Study Group, there have been improvements in staging. The liberal use of computed tomography also may have altered the types of early lung cancer diagnosed. Studies published since then have drawn contradictory conclusions on the benefit of lobectomy over sublobar resections for early-stage NSCLC. We examined the Surveillance Epidemiology End Results database to test our hypothesis that the relationship between extent of resection and outcome has changed since the Lung Cancer Study Group study was published. METHODS: We examined stage I NSCLCs ≤2 cm in size over three periods: 1988-1998 (Early), 1999-2004 (Intermediate), and 2005-2008 (Late). For each period, we assessed overall and disease-specific survivals and their associations with the extents of resection, by univariate and multivariate analyses. Sublobar resections in the Early group could not be categorized into segmentectomies and wedge resections because these were not coded separately. RESULTS: The proportion of NSCLCs ≤2 cm increased from 0.98% in 1988 to 2.2% in 2008. Multivariate analyses showed that sublobar resection was inferior to lobectomy in the Early period (hazard ratio [HR], 1.41; 95% confidence interval [CI], 1.21-1.65). This effect decreased in the Intermediate period, in which segmentectomies but not wedge resections were equivalent to lobectomies (wedge versus lobectomy HR, 1.19; 95% CI, 1.01-1.41; segmentectomy versus lobectomy HR, 1.04; 95% CI, 0.8-1.36). The difference disappeared in the Late period, when both wedge resections and segmentectomies were equivalent to lobectomy (wedge versus lobectomy HR, 1.09; 95% CI, 0.79-1.5; segmentectomy versus lobectomy HR, 0.83; 95% CI, 0.47-1.45). Trends for both overall survival and disease-specific survival were identical. CONCLUSIONS: The survival benefit of lobectomy over sublobar resection decreased over the past 2 decades with no discernible difference in the most contemporary cases. These results support reevaluation of lobectomy as the standard of care for small (≤2-cm) NSCLCs.
    Journal of Surgical Research 12/2012; · 2.12 Impact Factor
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    ABSTRACT: LEARNING OBJECTIVES Review thoracic anatomy that impacts surgical decision making: 1) Proximity to pulmonary vessels. 2) Proximity to great vessels/heart. 3) Involvement of airway/esophagus/chest wall. 4) Involvement of diaphragm/pericardium/phrenic nerve. ABSTRACT
    Radiological Society of North America 2012 Scientific Assembly and Annual Meeting; 11/2012
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    ABSTRACT: LEARNING OBJECTIVES Review controversial surgical treatment in lung cancer: 1) Sublobar resection versus lobar resection of small peripheral NSCLC or carcinoid tumor. 2) Surgical resection of single station N2 disease in NSCLC either before or after chemotherapy or chemoradiation.
    Radiological Society of North America 2012 Scientific Assembly and Annual Meeting; 11/2012
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    ABSTRACT: A 69-year-old man with presumed solid gastric mass determined by computed tomography, endoscopic ultrasonography, and fine-needle aspiration underwent videoscopic excision of what resulted in a cystic structure consistent with intra-abdominal esophageal duplication cyst. Esophageal duplication cysts are rare congenital lesions that are difficult to diagnose. They seldom occur entirely below the diaphragm, and occurrence in adults is unusual. Only six such cases are reported in the literature. When diagnosis is made, treatment decisions are not always straight forward, although excision is frequently pursued. The current case describes this unique finding and presents laparoscopic excision as a safe treatment alternative.
    The Thoracic and Cardiovascular Surgeon 11/2012; · 0.93 Impact Factor
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    ABSTRACT: The aim of this report is to describe technical maneuvers used to complete minimally invasive resections of the chest wall successfully. Case videos of advanced thoracoscopic chest wall resections performed at a comprehensive cancer center were reviewed, as were published reports. These were analyzed for similarities and also categorized to summarize alternative approaches. Limited chest wall resections en bloc with lobectomy can be accomplished with port placement similar to that used for typical thoracoscopic anatomic resections, particularly when the utility incision is close to the region of excision. Generally, chest wall resection precedes lobectomy. Ribs can be transected with Gigli saws, endoscopic shears, or high-speed drills. Division of bone and overlying soft tissue can be planned precisely using thoracoscopic guidance. Isolated primary chest wall masses may require different port position and selective reconstruction using synthetic materials. Patch anchoring can be accomplished by devices that facilitate laparoscopic port site fascial closure. Thoracoscopic chest wall resections have been accomplished safely using tools and maneuvers summarized here. Further outcomes research is necessary to identify the benefits of thoracoscopic chest wall resection over an open approach.
    The Journal of thoracic and cardiovascular surgery 06/2012; 144(3):S52-7. · 3.41 Impact Factor
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    ABSTRACT: The non-small cell lung cancer TNM classification system uses only the anatomic extent of lymph node (LN) metastases to define the N category. The number of LNs resected and the ratio of positive LNs to total examined LNs are prognostic in other solid tumors. We used the Surveillance, Epidemiology and End Results database to investigate the effect of these factors on the overall survival of non-small cell lung cancer. All patients with non-small cell lung cancer in the Surveillance, Epidemiology and End Results database from 1988 through 2007 who had curative resections and had at least one LN examined were included. The prognostic value of age, race, sex, tumor size, histologic grade, number of examined LNs, and ratio of positive LNs to total examined LNs was assessed using a multivariate Cox proportional hazards model for overall survival. The number of LNs examined was categorized into four levels. The percentage of positive LNs was stratified into three levels. Among patients with localized disease, fewer LNs examined corresponded with a worse prognosis. Prognosis improved as more LNs were examined. For patients with regional disease, the differences were significant only at the extremes. Older patients, males, and those with higher grade or larger tumors did worse. Patients with low or moderate ratios of positive to total LNs had better prognoses than those with high ratios. More LNs resected and lower ratios of positive LNs to total examined LNs are associated with better patient survival after non-small cell lung cancer resection independent of age, sex, grade, tumor size, and stage of disease.
    The Annals of thoracic surgery 03/2012; 93(5):1614-9; discussion 1619-20. · 3.45 Impact Factor
  • Journal of Surgical Research 02/2012; 172(2):188. · 2.12 Impact Factor
  • Samjot Singh Dhillon, Elisabeth U Dexter
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    ABSTRACT: Bronchoscopic techniques have seen significant advances in the last decade. The development and refinement of different types of endobronchial ultrasound and navigation systems have led to improved diagnostic yield and lung cancer staging capabilities. The complication rate of these minimally invasive procedures is extremely low as compared to traditional transthoracic needle biopsy and surgical sampling. These advances augment the safe array of methods utilized in the work up and management algorithms of lung cancer.
    Journal of Carcinogenesis 01/2012; 11:19.
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    ABSTRACT: Although a common clinical pairing, the epidemiology and prognosis of lung cancer (LC) after head and neck cancer (HNC) is not well described. Data from the database of the Surveillance, Epidemiology and End Results (SEER) Program were used to study the epidemiology and survival of patients with LC after HNC. These data were compared with those from our institutional cancer registry. Of all patients with a history of HNC in the SEER database, 8,225 (5%) patients went on to develop LC. This was more than three times the incidence of second primary lung cancers (1.5%). Subsequent LCs in patients with a history of HNC were more common among those with hypopharyngeal and laryngeal cancer and those with localized HNC. Patients with HNC followed by LC had poorer overall survival than did the overall population of patients with LCs in the SEER database. Overall survival after the onset of LC was dismal (median survival, 8 months). Survival was not affected by histologic concordance between HNC and LC. An analysis of 72 patients with LC after HNC reported in our institutional tumor registry over the past 37 years yielded similar results. Of patients who survive LC or HNC, the latter are much more likely to develop a new pulmonary malignancy. Lung cancers that develop after HNC have a poor prognosis. This phenomenon is not explained by misclassified metastases, because histologically discordant cases behave just as poorly. Enhanced surveillance and chemoprevention strategies are needed to detect and prevent subsequent primary LC in survivors of HNC.
    The Annals of thoracic surgery 09/2011; 92(3):1056-60; discussion 1060-1. · 3.45 Impact Factor
  • Franklin Dexter, Elisabeth U Dexter, Johannes Ledolter
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    ABSTRACT: Multiple logistic regression studies frequently are performed with duration (e.g., operative time) included as an independent variable. We use narrative review of the statistical literature to highlight that when the association between duration and outcome is presumptively significant, the procedure itself (e.g., video-assisted thoracoscopic lobectomy or thoracotomy lobectomy) needs to be tested for inclusion in the logistic regression. If the procedure is a true covariate but excluded in lieu of category of procedure (e.g., lung resection), estimates of the odds ratios for other independent variables are biased. In addition, actual durations are sometimes used as the independent variable, rather than scheduled (forecasted) durations. Only the scheduled duration is known when a patient would be randomized in a trial of preoperative or intraoperative intervention and/or meets with the surgeon and anesthesiologist preoperatively. By reviewing the literature about logistic regression and about predicting case duration, we show that the use of actual instead of scheduled duration can result in biased logistic regression results.
    Anesthesia and analgesia 08/2011; 113(5):1197-201. · 3.42 Impact Factor
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    ABSTRACT: Mediastinal lymph node dissection (MLND) is an integral component of complete resection for non-small cell lung cancer (NSCLC). This study analyzed the National Comprehensive Cancer Network's (NCCN) NSCLC Database to compare the efficacy of MLND during lobectomy by video-assisted thoracoscopy surgery (VATS) and thoracotomy (open). The NCCN NSCLC Database was queried to identify patients who underwent lobectomy to analyze the adequacy of MLND by the number of LN stations. The percentage of patients with at least three N2 stations, the number of N2 LN stations, and the total number of LN stations (N1+N2) resected was compared by approach. Of 4215 patients with NSCLC (January 2007 to September 2010), 388 patients underwent lobectomy (199 VATS and 189 open) and met entry criteria. The groups were similar in age, sex, comorbidities, performance status, and histology. MLN assessment was similar in both groups as measured by number of N2 stations (median, 3 stations; p=0.12). At least three MLN stations were assessed in 130 patients (66%) in the VATS group vs 107 patients (58%) in the open group (p=0.12). The total number of N1+N2 stations resected for each group was also similar (median, 4 in both groups (p=0.06). The NCCN database indicates at least three MLN stations were assessed in most patients who underwent lobectomy by either approach. As evaluated by the number of LN stations, there was no difference in the efficacy of MLN dissection by approach.
    The Annals of thoracic surgery 07/2011; 92(1):226-31; discussion 231-2. · 3.45 Impact Factor
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    ABSTRACT: The existing guidelines for extent of resection of carcinoid tumors are based on other, more malignant non-small cell lung cancers. Because of the small number of patients in any single institution, we analyzed the Surveillance Epidemiology and End Results (SEER) database to study the effect of the extent of resection of these tumors on overall survival. All patients with lung cancer in the SEER database from 1973 to 2006 with carcinoid tumors as their only cancer were included. Variables examined included age, race (white, black, others), gender, histologic type (atypical versus typical carcinoid), stage (localized, regional, and distant), extent of resection (sublobar resection, lobectomy, or more extensive) and survival. Univariate analyses (Kaplan-Meier method) were used to select variables for multivariate analysis (Cox regression analysis). Associations were considered significant with an alpha error < 5%. In addition, propensity score-matched Cox regression analysis was performed for patients with typical carcinoid disease. Most patients with carcinoid tumors did not acquire any other cancers (4,785/6,819; 70.2%). Of these, 797 patients had sublobar resection and 2,681 patients had lobectomy or more extensive resections. On univariate analysis, gender (p = 0.014), race (p < 0.001), stage (p < 0.001), histologic type (p < 0.001) and extent of resection (p = 0.04) were associated with overall survival. Multivariate analysis demonstrated that age, gender, race, stage, and histologic type remain statistically associated with overall survival and disease-specific survival, whereas extent of resection is not. Propensity score-matched analysis demonstrates that for typical carcinoid, extent of resection is not associated with overall survival when adjusted for age, gender, race, and stage. Sublobar resection of carcinoid tumors did not compromise oncologic outcomes in a large population-based database. Lobectomy for typical carcinoid tumors is not mandatory as long as complete resection and adequate mediastinal staging are performed.
    The Annals of thoracic surgery 06/2011; 92(5):1774-8; discussion 1778-9. · 3.45 Impact Factor
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    ABSTRACT: Preoperative pulmonary function tests are used to assess operability for either lobectomy or pneumonectomy. Current guidelines for defining high-risk patients for anatomic lung resection on the basis of these tests were developed in the era of open thoracotomy. We studied the outcomes of such high-risk patients after video-assisted thoracoscopic surgical resections to assess the performance of these guidelines. Records of all patients who underwent anatomic resection from 2001 to 2009 at a single institution were queried for pulmonary function and perioperative outcomes. Patients with predicted postoperative forced expiratory volume in 1 second or predicted postoperative lung carbon dioxide diffusing capacity less than 40% were considered to have limited pulmonary reserve. Perioperative outcomes of patients with limited pulmonary reserve who underwent thoracoscopic resection were documented and compared with those of similar patients who underwent open resection. Of 600 patients assessed, 70 had limited pulmonary reserve according to our criteria. Forty-seven of them underwent thoracoscopic resection. This cohort had excellent outcomes, with mortality of 2.1%, pneumonia rate of 4.3%, and discharge independence rate of 95.7%. Relative to contemporary patients undergoing open resection (N=23, including 12 conversions), patients undergoing thoracoscopic resection had lower incidence of pneumonia (4.3% vs. 21.7%, P<.05) and shorter intensive care unit stay (2 vs 4 days, P=.05). Patients with marginal lung function tolerate thoracoscopic anatomic resection well. Reassessment of the traditional pulmonary function test guidelines for operability is warranted in the current era of thoracoscopic lung surgery.
    The Journal of thoracic and cardiovascular surgery 02/2011; 141(2):459-62. · 3.41 Impact Factor
  • Source
    Jornal of Molecular Biomarkers & Diagnosis. 01/2011; 2(5).
  • Source
    Franklin Dexter, Elisabeth U Dexter, Johannes Ledolter
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    ABSTRACT: Predictive variability of operating room (OR) times influences decision making on the day of surgery including when to start add-on cases, whether to move a case from one OR to another, and where to assign relief staff. One contributor to predictive variability is process variability, which arises among cases of the same procedure(s). Another contributor is parameter uncertainty, which is caused by small sample sizes of historical data. Process variability was quantified using absolute percentage errors of surgeons' bias-corrected estimates of OR time. The influence of procedure classification on process variability was studied using a dataset of 61,353 cases, each with 1 to 5 scheduled and actual Current Procedural Terminology (CPT) codes (i.e., a standardized vocabulary). Parameter uncertainty's sensitivity to sample size was quantified by studying ratios of 90% prediction bounds to medians. That studied dataset of 65,661 cases was used previously to validate a Bayesian method to calculate 90% prediction bounds using combinations of surgeons' scheduled estimates and historical OR times. (1) Process variability differed significantly among 11 groups of surgical specialty and case urgency (P < 0.0001). For example, absolute percentage errors exceeded the overall median of 22% for 57% of urgent spine surgery cases versus 42% of elective spine surgery cases. (2) Process variability was not increased when scheduled and actual CPTs differed (P = 0.23 without and P = 0.47 with stratification based on the 11 groups), because most differences represented known (planned) options inherent to procedures. (3) Process variability was not associated with incidence of procedures (P = 0.79), after excluding cataract surgery, a procedure with high relative variability. (4) Parameter uncertainty from uncommon procedures (0-2 historical cases) accounted for essentially all of the uncertainty in decisions dependent on estimates of OR times. The Bayesian method moderated the effect of small sample sizes on uncertainty in estimates of OR times. In contrast, from prior work, the use of broad categories of procedures reduces parameter uncertainty but at the expense of increased process variability. For procedures with few historic data, the Bayesian method allows for effective case duration prediction, permitting use of detailed procedure descriptions. Although fine resolution of scheduling procedures increases the chance of performed procedure(s) differing from scheduled procedure(s), this does not increase process variability. Future studies need both to address differences in process variability among specialties and accept the limitation that findings from one may not apply to others.
    Anesthesia and analgesia 04/2010; 110(4):1155-63. · 3.42 Impact Factor

Publication Stats

300 Citations
120.02 Total Impact Points


  • 2013–2014
    • Roswell Park Cancer Institute
      • Department of Thoracic Surgery
      Buffalo, New York, United States
  • 2011–2013
    • University at Buffalo, The State University of New York
      • Department of Surgery
      Buffalo, New York, United States
  • 1998–2010
    • University of Iowa
      • • Department of Anesthesia
      • • Department of Surgery
      Iowa City, IA, United States
  • 2005
    • State University of New York Upstate Medical University
      Syracuse, New York, United States