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Dive into the research topics where Karen M. Rieger is active.

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Featured researches published by Karen M. Rieger.


The Journal of Thoracic and Cardiovascular Surgery | 1999

Primary mediastinal nonseminomatous germ cell tumors: The influence of postchemotherapy pathology on long-term survival after surgery

Kenneth A. Kesler; Karen M. Rieger; Kristen N. Ganjoo; Matt Sharma; Naomi S. Fineberg; Lawrence H. Einhorn; John W. Brown

OBJECTIVES The treatment of nonseminomatous germ cell tumors with cisplatin-based chemotherapy followed by aggressive surgical resection of residual disease is one of the most successful models for multimodality cancer therapy. We reviewed the case histories of 91 patients treated at our institution from 1981 to 1998 with primary mediastinal nonseminomatous germ cell tumors to evaluate variables that may influence survival after surgery. METHODS Twelve of the 91 patients did not undergo postchemotherapy resection because of progressive disease. Seventy-nine of them underwent 82 thoracic surgical procedures and are the basis of this review. The majority (71/75) had elevated serum tumor markers, 75% (n = 50) of which returned to normal levels after first- or second-line chemotherapy. RESULTS There were 3 operative deaths and 1 late death, attributed to pulmonary complications. Twenty-four patients died of recurrent disease and 3 of leukemia, for an overall survival of 61% after an average follow-up of 48 months. The pathologic findings of complete tumor necrosis (n = 19) and benign teratoma (n = 28) in the surgical specimen predicted excellent and good long-term survival, respectively, which was statistically better than that of patients having persistent nonseminomatous germ cell tumors (n = 24) or carcinomatous/sarcomatous degeneration (n = 8). CONCLUSIONS Primary nonseminomatous germ cell tumors of the mediastinum can be cured with a multimodality therapy, particularly in the subset of patients with postchemotherapy pathologic findings of tumor necrosis and teratoma. Survival is poor but possible in patients with unfavorable pathologic findings after chemotherapy, currently justifying an aggressive surgical approach in patients with otherwise operable disease.


American Journal of Cardiology | 2003

Left anterior descending coronary artery wall thickness measured by high-frequency transthoracic and epicardial echocardiography includes adventitia☆

Irmina Gradus-Pizlo; Brian Bigelow; Yousuf Mahomed; Stephen G. Sawada; Karen M. Rieger; Harvey Feigenbaum

High-frequency, 2-dimensional transthoracic echocardiography (HR-2DTTE) measurements of the left anterior descending (LAD) coronary artery wall thickness are larger than measurements obtained by intravascular ultrasound. We hypothesize that this difference is due to inclusion of the third vascular layer, which may represent adventitia by HR-2DTTE, and that this layer must be increasing in thickness with the development of atherosclerosis. We evaluated the contribution of this third layer to the wall thickness of the normal and atherosclerotic LAD artery imaged by HR-2DTTE using high-frequency epicardial echocardiography (HFEE) as the reference standard. Eighteen patients (10 men, mean age 62 years), 13 with coronary atherosclerosis and 5 with normal coronary arteries, referred for open-heart surgery, underwent preoperative HR-2DTTE evaluation of the LAD artery (SONOS 5500; 3- to 8-MHz transducer) and intraoperative HFEE of the LAD artery (SONOS 5500; 6- to 15-MHz transducer). Wall thickness was greater in patients with coronary atherosclerosis than in those with normal coronary arteries by both HR-2DTTE (1.9 +/- 0.3 vs 1.0 +/- 0.1 mm, p = <0.001) and HFEE (1.8 +/- 0.2 vs 1.0 +/- 0.2 mm, p = <0.001). On HFEE, the average intima plus media thickness was greater in patients with coronary atherosclerosis than in those with normal coronary arteries (0.78 +/- 0.3 vs 0.34 +/- 0.1 mm, p = 0.005). The average thickness of adventitia was also greater in patients with coronary atherosclerosis than in those with normal coronary arteries (0.92 +/- 0.2 vs 0.54 +/- 0.2 mm, p = 0.0005). HR-2DTTE and HFEE measurements of the wall thickness correlated well (r = 0.83 [reader 1], p <0.001; r = 0.61 [reader 2], p <0.01). A third vascular layer, which likely included adventitia, represents a significant portion of the LAD wall thickness imaged by HR-2DTTE and HFEE, and it significantly increases in thickness with the development of atherosclerosis.


The Annals of Thoracic Surgery | 2009

A Randomized Trial Evaluating Amiodarone for Prevention of Atrial Fibrillation After Pulmonary Resection

James E. Tisdale; Heather A. Wroblewski; Donna S. Wall; Karen M. Rieger; Zane T. Hammoud; Jerry V. Young; Kenneth A. Kesler

BACKGROUND Atrial fibrillation (AF) occurs commonly after anatomic pulmonary resection. In this study, the efficacy of amiodarone for prevention of post-pulmonary resection AF was investigated. METHODS One hundred thirty patients undergoing lobectomy, bilobectomy, or pneumonectomy were randomly assigned prospectively to receive amiodarone (n = 65) or no prophylaxis (control group, n = 65). The amiodarone group received 1,050 mg by continuous intravenous infusion over 24 hours, initiated at the time of anesthesia induction, followed by 400 mg orally twice daily until hospital discharge or for a maximum of 6 days. The primary endpoint was AF requiring treatment during hospitalization. Secondary endpoints included postoperative length of hospital and intensive care unit stays. RESULTS There were no significant differences between the amiodarone and control groups in demographics, comorbid conditions, extent of pulmonary resection, or preoperative or postoperative use of beta-blockers or calcium-channel blockers. The incidence of AF was lower in the amiodarone group than in the control group (13.8% versus 32.3%, p = 0.02; relative risk reduction = 57%). There was no difference between the amiodarone and control groups in median length of hospital stay (7 versus 8 days, p = 0.79), but median length of intensive care unit stay was shorter in the amiodarone group (46 versus 84 hours, p = 0.03). There was no significant difference between the amiodarone and control groups in the incidence of pulmonary complications or other adverse effects. CONCLUSIONS Amiodarone prophylaxis significantly reduces the incidence of AF after anatomic pulmonary resection, and is associated with a significant reduction in length of intensive care unit stay.


The Annals of Thoracic Surgery | 2008

A 25-Year Single Institution Experience With Surgery for Primary Mediastinal Nonseminomatous Germ Cell Tumors

Kenneth A. Kesler; Karen M. Rieger; Zane T. Hammoud; Laura E. Kruter; Susan M. Perkins; Mark W. Turrentine; Bryan P. Schneider; Lawrence H. Einhorn; John W. Brown

BACKGROUND The treatment of primary mediastinal nonseminomatous germ cell tumors (PMNSGCT) with cisplatin-based chemotherapy, followed by surgical resection of residual disease, has been established. We reviewed our institutions 25-year experience in the cisplatin era to determine surgical risks and predictors of survival after surgery for PMNSGCT. METHODS A total of 158 patients (mean age, 29 +/- 8 years) who underwent postchemotherapy operations for PMNSGCT were reviewed and multiple variables analyzed. RESULTS Ten (6%) operative deaths occurred, nine of which were attributed to respiratory failure, and 26 (18%) patients experienced postoperative complications, including 9 with respiratory failure. None of 17 recent patients who received chemotherapy regimens that did not contain bleomycin experienced pulmonary complications (p = 0.12 vs patients who received bleomycin). Operative survivors were followed up a median of 34 months (range, 1 to 194 months). Multivariable analysis demonstrated that the postchemotherapy pathologic category of complete necrosis vs teratoma), persistent germ cell or nongerm cell cancer, and elevated serum tumor markers after operation were independently predictive of survival. CONCLUSIONS Operative risks for PMNSGCT appear to be improved with the use of chemotherapy regimens that do not contain bleomycin. Patients pathologically demonstrating complete tumor necrosis in the residual mass after chemotherapy have excellent long-term survival, with decreasing survival after resection of teratoma and persistent germ cell or nongerm cell cancer. Patients pathologically demonstrating persistent germ cell or nongerm cell cancer have poor but possible long-term survival, which justifies an aggressive surgical approach in patients who are deemed operable.


The Journal of Thoracic and Cardiovascular Surgery | 2010

A randomized, controlled study of amiodarone for prevention of atrial fibrillation after transthoracic esophagectomy

James E. Tisdale; Heather A. Wroblewski; Donna S. Wall; Karen M. Rieger; Zane T. Hammoud; Jerry V. Young; Kenneth A. Kesler

OBJECTIVE Atrial fibrillation is common after esophagectomy. The objective of this study was to determine the efficacy and safety of amiodarone for prevention of atrial fibrillation after transthoracic esophagectomy. METHODS Eighty patients undergoing transthoracic esophagectomy were randomly, prospectively assigned to receive amiodarone (n = 40) or no prophylaxis (control group, n = 40). Amiodarone-treated patients received the drug by continuous infusion, initiated at the time of induction of anesthesia, at a rate of 0.73 mg/min (43.75 mg/h), and continued for 96 hours (total dose 4200 mg). The primary end point was atrial fibrillation requiring treatment. Secondary end points included any atrial fibrillation lasting longer than 30 seconds and postoperative hospital and intensive care unit stays. RESULTS There were no significant differences between the amiodarone and control groups in demographic characteristics, comorbid conditions, or preoperative or postoperative use of beta-blockers or calcium-channel blockers. The incidence of atrial fibrillation requiring treatment was lower in the amiodarone group than in the control group (15% vs 40%, P = .02, relative risk reduction 62.5%). There were no significant differences between the amiodarone and control groups in median hospital stay (11 days vs 12 days, P = .31) or median intensive care unit stay (68 hours vs 77 hours, p = .097). There were no significant difference between the groups in the incidences of adverse effects. CONCLUSIONS Amiodarone prophylaxis significantly reduced the incidence of atrial fibrillation after transthoracic esophagectomy.


The Annals of Thoracic Surgery | 2012

Thymic carcinoma: Outcomes after surgical resection

Ikenna C. Okereke; Kenneth A. Kesler; Richard K. Freeman; Karen M. Rieger; Thomas J. Birdas; Anthony J. Ascioti; Sunil Badve; Robert P. Nelson; Patrick J. Loehrer

BACKGROUND Thymic carcinoma is a rare malignancy with little information regarding outcomes after therapy with curative intent. We undertook a retrospective analysis of all patients who underwent resection of thymic carcinoma at 2 hospitals. METHODS From 1990 to 2011, 16 patients (9 men, 7 women) underwent surgical resection of thymic carcinoma at a mean age of 52 years. Patient demographics, extent of surgical resection, and outcomes were compiled. RESULTS The distribution of Masaoka stages at presentation was I in 3 (19%), II in 4 (25%), III in 8 (50%), and IV in 1 (6%). Neoadjuvant chemotherapy was administered to 6 patients (38%) whose tumors were deemed to be more locally invasive. Surgical resection included en bloc extrapleural pneumonectomy in 1, lobectomy in 2, and superior vena cava resection and reconstruction in 4. There were no perioperative deaths. Complete resection was achieved in 14 (88%), and of these patients, only 1 experienced local recurrence. At last follow-up, 10 patients were alive and well, 1 patient was alive with disease, and 5 patients had died. Mean survival was 4.2 years. CONCLUSIONS Although considered to have greater malignant potential, long-term survival can be achieved in patients with thymic carcinoma who are amenable to surgical therapy. With increased use of computed tomography imaging, patients with early-stage disease are being identified more frequently, and complete surgical resection appears to have favorable cure rates in these patients. Select patients with locally advanced disease can experience long-term survival with a multimodality approach.


The Annals of Thoracic Surgery | 2010

Prognostic indicators after surgery for thymoma.

Ikenna C. Okereke; Kenneth A. Kesler; Mohamed H. Morad; Deming Mi; Karen M. Rieger; Thomas J. Birdas; Sunil Badve; John D. Henley; Mark W. Turrentine; Robert P. Nelson; Patrick J. Loehrer

BACKGROUND We undertook a 20-year retrospective institutional study to investigate prognostic indicators after surgery for thymoma. METHODS From 1989 to 2009, 83 patients underwent surgical resection of thymoma or thymic carcinoma at our institution. Twelve of these patients were determined to have either World Health Organization type C disease or Masaoka stage IV-B disease and were excluded from analysis. The remaining 71 patients were reviewed. RESULTS The majority of patients in this series were female 64.7% (n=46) with an overall average age of 51.0 years. The distribution of Masaoka stages I, II, III, and IV-A was 40.8% (n=29), 19.7% (n=14), 18.3% (n=13), and 21.1% (n=15), respectively. Thirteen of the 28 (46.2%) patients who presented with stage III or IV-A disease received preoperative chemotherapy. After a mean follow-up of 66 months (range, 6 to 241 months), 54 (75.3%) patients are alive and well while six are alive with disease. Eleven (16.0%) patients have died, but only 3 (4.3%) of these patients died of thymoma. The overall disease-specific survival was 97% and 89% at 5 and 10 years. Of the variables analyzed, only age was predictive of overall survival (p=0.03). Masaoka stages I to III as compared with stage IV-A was significantly predictive of disease-free survival (p<0.01). CONCLUSIONS Long-term disease-specific survival can be expected not only after surgery for early stage thymoma but also after surgery for advanced disease, including patients with pleural metastases. However, patients who undergo surgery for stage IV-A disease have reduced disease-free survival. Late mortality due to secondary cancers and associated immunologic disorders was more frequent than mortality from thymoma in this series.


Clinical Cancer Research | 2011

Prediction of Postoperative Recurrence-Free Survival in Non-small Cell Lung Cancer by Using an Internationally Validated Gene Expression Model

Ranjana Mitra; Jinseon Lee; Jisuk Jo; Monica Milani; Jeanette N. McClintick; Howard J. Edenberg; Kenneth A. Kesler; Karen M. Rieger; Sunil Badve; Oscar W. Cummings; Ahmed Mohiuddin; Dafydd G. Thomas; Xianghua Luo; Beth E. Juliar; Lang Li; Clementina Mesaros; Ian A. Blair; Anjaiah Srirangam; Robert A. Kratzke; Clement J. McDonald; Jhingook Kim; David A. Potter

Purpose: This study was performed to discover prognostic genomic markers associated with postoperative outcome of stage I to III non–small cell lung cancer (NSCLC) that are reproducible between geographically distant and demographically distinct patient populations. Experimental Design: American patients (n = 27) were stratified on the basis of recurrence and microarray profiling of their tumors was performed to derive a training set of 44 genes. A larger Korean patient validation cohort (n = 138) was also stratified by recurrence and screened for these genes. Four reproducible genes were identified and used to construct genomic and clinicogenomic Cox models for both cohorts. Results: Four genomic markers, DBN1 (drebrin 1), CACNB3 (calcium channel beta 3), FLAD1 (PP591; flavin adenine dinucleotide synthetase), and CCND2 (cyclin D2), exhibited highly significant differential expression in recurrent tumors in the training set (P < 0.001). In the validation set, DBN1, FLAD1 (PP591), and CACNB3 were significant by Cox univariate analysis (P ≤ 0.035), whereas only DBN1 was significant by multivariate analysis. Genomic and clinicogenomic models for recurrence-free survival (RFS) were equally effective for risk stratification of stage I to II or I to III patients (all models P < 0.0001). For stage I to II or I to III patients, 5-year RFS of the low- and high-risk patients was approximately 70% versus 30% for both models. The genomic model for overall survival of stage I to III patients was improved by addition of pT and pN stage (P < 0.0013 vs. 0.010). Conclusion: A 4-gene prognostic model incorporating the multivariate marker DBN1 exhibits potential clinical utility for risk stratification of stage I to III NSCLC patients. Clin Cancer Res; 17(9); 2934–46. ©2011 AACR.


The Annals of Thoracic Surgery | 2011

Survival after resection for metastatic testicular nonseminomatous germ cell cancer to the lung or mediastinum.

Kenneth A. Kesler; Laura E. Kruter; Susan M. Perkins; Karen M. Rieger; Katherine J. Sullivan; Matthew L. Runyan; John W. Brown; Lawrence H. Einhorn

BACKGROUND Since the advent of cisplatin-based chemotherapy, nonseminomatous germ cell tumors (NSGCT) have been considered one of the most curable solid neoplasms and a model for multimodality cancer therapy. We undertook an institutional review of testicular NSGCT patients who underwent operations to remove lung or mediastinal metastases after chemotherapy in the cisplatin era to determine outcomes. METHODS From 1980 to 2006, 431 patients underwent 640 postchemotherapy surgical procedures to remove lung (n = 159, 36.8%), mediastinal (n = 136, 31.6%), or both lung and mediastinal (n = 136, 31.6%) metastases within 2 years of chemotherapy. Multiple variables potentially predictive of survival were analyzed. RESULTS The overall median survival was 23.4 years, with 295 (68%) patients alive and well after an average follow-up of 5.6 years. There was no survival difference in patients who underwent removal of lung or mediastinal metastases. Pathologic categories of resected residual disease were necrosis (21.5%), teratoma (52.7%), persistent NSGCT (15.0%), and degenerative non-germ cell cancer (10.1%). Multivariable analysis identified older age at time of diagnosis (p = 0.001), non-germ cell cancer in testes specimen (p = 0.004), and pathology of residual disease (p < 0.001) as significantly predictive of survival. CONCLUSIONS Patients who undergo resection of residual lung or mediastinal disease for metastatic testicular NSGCT as a planned approach after cisplatin-based chemotherapy have overall excellent long-term survival. Survival is equivalent comparing hematogenous and lymphatic routes of metastases but depends on the pathology of the resected disease. These results justify an aggressive surgical approach, particularly to remove residual teratoma in the lung or mediastinum after chemotherapy, including multiple surgical procedures if necessary.


The Annals of Thoracic Surgery | 2009

Surgical management of pulmonary and mediastinal sequelae of histoplasmosis: a challenging spectrum.

Zane Hammoud; Anthony S. Rose; Chadi A. Hage; Kenneth S. Knox; Karen M. Rieger; Kenneth A. Kesler

BACKGROUND Histoplasmosis may result in a spectrum of complications that require thoracic surgical intervention. We reviewed our 17-year experience in the management of histoplasmosis to determine outcomes as well as gain insight into the distribution of complications requiring surgical intervention. METHODS The hospital records of patients who underwent surgical treatment for complications related to histoplasmosis from 1991 to 2008 were reviewed. Based on the predominant presentation, patients were categorized with complications secondary to broncholithiasis, granulomatous disease, or fibrosing mediastinitis. Patients who underwent diagnostic surgery and were found to have histoplasmosis were excluded. RESULTS Of the 49 patients who underwent surgery for histoplasmosis-related complications, 27 (55%) had granulomatous disease, 13 (27%) had broncholithiasis, and 9 (18%) had fibrosing mediastinitis. The most common clinical presentations were recurrent pneumonia (n = 16) and hemoptysis (n = 13); less common presentations included dysphagia (n = 3) and superior vena cava syndrome (n = 1). Two patients required cardiopulmonary bypass for resection; 1 of these died postoperatively (series mortality 2%). Seven patients (14%) had complications. Relief of symptoms was achieved in all surviving patients. CONCLUSIONS Complications of histoplasmosis requiring thoracic surgical intervention are diverse with pulmonary complications predominating. Although surgically challenging, excellent short- and long-term outcomes may be expected.

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Ikenna C. Okereke

University of Texas Medical Branch

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