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Featured researches published by Alexander Patterson.


Journal of Thoracic Oncology | 2008

Prognostic Value of Preoperative Positron Emission Tomography in Resected Stage I Non-small Cell Lung Cancer

Boone Goodgame; Giancarlo Pillot; Zhiyun Yang; Jabi Shriki; Bryan F. Meyers; Jennifer Bell Zoole; Feng Gao; Farrokh Dehdashti; Alexander Patterson; Barry A. Siegel; Ramaswamy Govindan

Purpose: Approximately 20 to 40% of patients with surgically resected stage I non-small cell lung cancer (NSCLC) will develop recurrent disease. Positron emission tomography (PET) with 2-[18F] fluoro-2-deoxy-D-glucose (FDG) is used often in staging NSCLC. We conducted this study to determine whether the preoperative maximum tumor standardized uptake value (SUVmax) was associated with recurrence in patients with resected stage I NSCLC. Patients and Methods: We identified consecutive patients who underwent curative surgical resection for stage I NSCLC between 1999 and 2003 who had preoperative FDG-PET imaging. Patients were divided into two cohorts based on SUVmax above or below the median for the group. Recurrence rates were estimated by the Kaplan-Meier method and overall survival was analyzed as a secondary end point. Results: Of 136 patients who met inclusion criteria, 77 (57%) had T1 and 59 (43%) had T2 tumors. The median follow-up time was 46 months and 32 patients had a disease recurrence. The median SUVmax was 5.5. The 5-year estimates of recurrence rates for patients with low and high SUVmax were 14% and 37%, respectively (p = 0.002), with 5-year overall survivals of 74% and 53%, respectively (p = 0.006). In multivariate analyses based on SUVmax, T-classification, age, and histology, high SUVmax was independently associated with recurrence (p = 0.002) and mortality (p = 0.041). Conclusion: High SUVmax (≥5.5) on preoperative FDG-PET is an independent predictor of relapse and death in resected stage I NSCLC. Prospective trials of adjuvant chemotherapy in patients with stage I NSCLC and high SUVmax should be considered.


Journal of Thoracic Oncology | 2009

Risk of Recurrence of Resected Stage I Non-small Cell Lung Cancer in Elderly Patients as Compared with Younger Patients

Boone Goodgame; Avinash Viswanathan; Jennifer Bell Zoole; Feng Gao; C. Ryan Miller; Janakiraman Subramanian; Bryan F. Meyers; Alexander Patterson; Ramaswamy Govindan

Purpose: Half of all patients with non-small cell lung cancer (NSCLC) are 70 years or older at the time of diagnosis. Surgery is an option for fit elderly patients with early stage disease, but rates of disease recurrence after surgical resection are not well described. We report the outcomes in elderly patients (70 years or older) with stage I NSCLC after surgical resection. Patients and Methods: We conducted a retrospective study of patients diagnosed with stage I NSCLC after surgical resection at Washington University School of Medicine-Alvin J. Siteman Cancer Center from 1990 to 2000. Demographic, pathologic, treatment, and follow-up data were collected. Recurrence rates and overall survival were calculated by the Kaplan-Meier method. Multivariate Cox proportional hazards models were used to detect associations between potential prognostic factors and survival and recurrence. Results: Of the 715 patients with stage I NSCLC, 286 were 70 years or older at diagnosis. In this elderly cohort, the median age was 74 years (range, 70–89 years) and 140 of them were women (49%). Lobectomy was performed in 237 patients (83%) whereas 43 patients (15%) had a wedge or segmental resection, and six patients (2%) underwent pneumonectomy. Clinical and pathologic characteristics were not statistically different between the elderly and younger cohorts, with the exception that older patients were more likely to be white (90% versus 80%, p = 0.0003) and less likely to be smokers (88% versus 95%, p = 0.019) compared with the younger cohort. With a median follow-up of 4.6 years, the overall 5-year survival rate was 52% with a 5-year recurrence rate of 24%. In comparison, the patients younger than 70 years had a 5-year survival rate of 67% (p < 0.001) and a 5-year recurrence rate of 24%. Conclusions: Although overall survival was worse in elderly patients, estimated disease recurrence rates after resection were identical.


Journal of Heart and Lung Transplantation | 2013

Pre-transplant antibodies to Kα1 tubulin and collagen-V in lung transplantation: Clinical correlations

Venkataswarup Tiriveedhi; Baskaran Gautam; Nayan J. Sarma; Medhat Askar; Marie Budev; Aviva Aloush; Ramsey Hachem; Elbert P. Trulock; Bryan Myers; Alexander Patterson; Thalachallour Mohanakumar

BACKGROUND Immune responses to lung-associated self-antigens (SAgs) have been implicated in chronic lung allograft rejection. The goals of this study were to determine the prevalence of pre-existing antibodies (Abs) to the SAgs in pulmonary diseases and the association between pre-existing Abs to SAgs and the development of primary graft dysfunction (PGD), donor-specific antibodies (DSA), and chronic rejection. METHODS Pre- and post-transplant sera were analyzed from 317 lung transplant (LTx) recipients between 2000 and 2011 with diagnosis of chronic obstructive disease (n = 161), idiopathic pulmonary fibrosis (IPF; n = 50), cystic fibrosis (CF; n = 55), and others (n = 51). Samples were analyzed for Abs to SAgs by enzyme-linked immunosorbent assay, and DSA and cytokines by Luminex. The clinical diagnosis of PGD and bronchiolitis obliterans syndrome (BOS) was based on International Society for Heart and Lung Transplantation guidelines. RESULTS The overall prevalence of Abs to SAgs was 22.71%, including 18% in chronic obstructive pulmonary disease (p = 0.033), 34% in IPF (p = 0.0006), 29% in CF (p = 0.0023), and 19.6% in other diagnoses (p = 0.044). The incidence of PGD (88% vs 54%, p < 0.05), DSA (70% vs 45%, p < 0.01), and BOS (90% vs 38% (p < 0.001) after LTx was significantly higher in patients with pre-LTx Abs to SAgs than without. Pro-inflammatory cytokines (interleukin-1β, interleukin-17, and interferon-γ) were elevated in patients who had pre-LTx Abs to SAgs, along with a reduction in anti-inflammatory interleukin-10. CONCLUSIONS Patients with IPF and CF have the highest prevalence of Abs to SAgs. Patients with pre-existing Abs to SAgs are at increased risk for development of PGD, DSA, and BOS. Strategies to remove pre-existing Abs to SAgs should be considered to improve lung allograft outcome.


PLOS ONE | 2012

Antibodies to MHC Class II Molecules Induce Autoimmunity :Critical Role for Macrophages in the Immunopathogenesis of Obliterative Airway Disease

Masashi Takenaka; Venkataswarup Tiriveedhi; Vijay Subramanian; Kiyotaka Hoshinaga; Alexander Patterson; Thalachallour Mohanakumar

Previous studies have shown that intrabronchial administration of antibodies (Abs) to MHC class I resulted in development of obliterative airway disease (OAD), a correlate of chronic human lung allograft rejection. Since development of Abs specific to mismatched donor HLA class II have also been associated with chronic human lung allograft rejection, we analyzed the role of Abs to MHC class II in inducing OAD. Administration of MHC class II Abs (M5/114) to C57BL/6 mice induced the classical features of OAD even though MHC class II expression is absent de novo on murine lung epithelial and endothelial cells. The induction of OAD was accompanied by enhanced cellular and humoral immune responses to self-antigens (Collagen V and K- α1Tubulin). Further, lung-infiltrating macrophages demonstrated a switch in their phenotype predominance from MΦ1 (F4/80+CD11c+) to MΦ2 (F4/80+CD206+) following administration of Abs and prior to development of OAD. Passive administration of macrophages harvested from animals with OAD but not from naïve animals induced OAD lesions. We conclude that MHC class II Abs induces a phenotype switch of lung infiltrating macrophages from MΦ1 (F4/80+CD11c+) to MΦ2 (F4/80+CD206+) resulting in the breakdown of self-tolerance along with an increase in autoimmune Th17 response leading to OAD.


Journal of Heart and Lung Transplantation | 2010

Synergistic effect of antibodies to human leukocyte antigens and defensins in pathogenesis of bronchiolitis obliterans syndrome after human lung transplantation.

Deepti Saini; Nataraju Angaswamy; Venkataswarup Tiriveedhi; Naohiko Fukami; Ramsey Hachem; Elbert P. Trulock; B.F. Meyers; Alexander Patterson; Thalachallour Mohanakumar

BACKGROUND This study aims to determine the role of antibodies to donor-mismatched human leukocyte antigen (HLA) developed during the post-transplant period in inducing defensins and their synergistic role in the pathogenesis of chronic rejection, bronchiolitis obliterans syndrome (BOS), after human lung transplantation (LTx). METHODS Bronchoalveolar lavage (BAL) and serum from 21 BOS+ LTx patients were assayed for β-defensins human neutrophil peptides (HNP) 1-3 (enzyme-linked immunosorbent assay [ELISA]) and anti-HLA antibodies (Luminex, Luminex Corp, Austin, TX). Human airway epithelial cells (AEC) were treated with anti-HLA antibodies, HNP-1/2, or both, and the levels of β-defensin were measured by ELISA. Using a mouse model of obliterative airway disease induced by anti-major histocompatibility (MHC) class-I antibodies, we quantitatively and qualitatively determined neutrophil infiltration by myeloperoxidase (MPO) staining and activity by MPO assay, and defensin levels in the BAL. RESULTS In human LTx patients, higher defensin levels correlated with presence of circulating anti-HLA antibodies (p < 0.05). AEC treated with anti-HLA antibodies or HNP-1/2, produced β-defensin with synergistic effects in combination (612 ± 06 vs 520 ± 23 pg/ml anti-HLA antibody, or 590 ± 10 pg/ml for HNP treatment; p < 0.05). Neutrophil numbers (6-fold) and activity (5.5-fold) were higher in the lungs of mice treated with anti-MHC antibodies vs control. A 2-fold increase in α-defensin and β-defensin levels was also present in BAL on Day 5 after anti-MHC administrations. CONCLUSIONS Anti-HLA antibodies developed during the post-transplant period and α-defensins stimulated β-defensin production by epithelial cells, leading to increased cellular infiltration and inflammation. Chronic stimulation of epithelium by antibodies to MHC and resulting increased levels of defensins induce growth factor production and epithelial proliferation contributing to the development of chronic rejection after LTx.


American Journal of Clinical Oncology | 2008

A Clinical Model to Estimate Recurrence Risk in Resected Stage I Non-Small Cell Lung Cancer

Boone Goodgame; Avinash Viswanathan; C. Ryan Miller; Feng Gao; Bryan F. Meyers; Richard J. Battafarano; Alexander Patterson; Joel D. Cooper; Tracey J. Guthrie; Jeffrey D. Bradley; Giancarlo Pillot; Ramaswamy Govindan

Objective:There are no reliable markers to predict recurrence in resected Stage I non-small cell lung cancer (NSCLC). A validated clinical model to estimate the risk of recurrence would help select patients for adjuvant therapy. Methods:We reviewed the medical records of 715 patients who had a potentially curative resection for Stage I NSCLC at our institution from 1990 to 2000. Recurrence rates were estimated by the Kaplan-Meier method. A model to estimate risk of recurrence was developed by combining independent risk factors. Results:With a median follow-up of 4.7 years, the 5-year survival rates for Stages IA and IB were 66% and 55% respectively, and 5-year recurrence rates were 19% and 30%, respectively. Four factors were independently associated with tumor recurrence: tumor size >3 cm (hazard ratio [HR] = 2.4), surgery other than lobectomy (HR = 2.0), nonsquamous histology (HR = 1.4), and high-grade cellular differentiation (HR = 1.4). A scoring system for recurrence was developed by assigning 2 points for each major risk factor (tumor size and surgery) and 1 point for each minor risk factor (histologic subtype and cellular grade). Scores were grouped as low (0–1), intermediate (2–3), and high (>3), yielding 5-year estimates of risk of recurrence of 14%, 27%, and 43%, respectively. Conclusion:This model, based upon readily available clinicopathologic characteristics, can estimate the risk of recurrence in Stage I NSCLC, independent of T classification. This model could be used to select patients for adjuvant therapy if validated in independent data sets.


The Journal of Thoracic and Cardiovascular Surgery | 2013

Attaining proficiency with endobronchial ultrasound-guided transbronchial needle aspiration.

Yinin Hu; Varun Puri; Traves D. Crabtree; Daniel Kreisel; Alexander S. Krupnick; Alexander Patterson; Bryan F. Meyers

OBJECTIVES Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is becoming the preferred method of mediastinal staging for lung cancer. We investigated the learning curve for EBUS-TBNA using risk-adjusted cumulative sum (Cusum). METHODS A retrospective study of EBUS-TBNA was performed at a single academic institution for patients with mediastinal or hilar lymphadenopathy in the setting of proven or suspected lung cancer. A sampling pass was defined as a full retraction and repositioning of the aspiration needle. Rapid on-site evaluation was not available. To track proficiency, risk-adjusted Cusum analysis was performed using acceptable and unacceptable failure rates of 10% and 20%, respectively. Failure was defined as false negative or nondiagnostic results. RESULTS During the study period, 231 patients underwent EBUS-TBNA. Prevalence of mediastinal or hilar malignancy was 66.7% (154 out of 231). Sensitivity was 92.2% (142 out of 154), and negative predictive value was 87.9% (58 out of 66). Node size was identified as a significant predictor of EBUS-TBNA success by multiple regression. Risk-adjusted Cusum analysis demonstrated that the first and only unacceptable decision interval was crossed at 22 cases. Individual practitioner learning curves were highly variable, and the operator with the highest volume was the most consistently proficient. CONCLUSIONS In our experience, attainment of an acceptable failure rate for EBUS-TBNA required 22 cases. Node size is a predictor of EBUS-TBNA success. Risk-adjusted Cusum proved a powerful evaluative tool to monitor the training process of this new procedure.


Journal of Thoracic Oncology | 2008

Esophageal carcinoma with celiac nodal metastases; Curative or palliative?

Marco Trovo; Jeffrey D. Bradley; Issam El Naqa; Ethan Foster; Bryan F. Meyers; Ramaswamy Govindan; Alexander Patterson

Introduction: To determine the prognostic value of celiac lymphadenopathy for patients with esophageal or gastroesophageal junction carcinomas treated with neoadjuvant or definitive chemoradiotherapy. Methods: The records of patients undergoing chemoradiation therapy for esophageal cancer, who received a dose of at least 45 Gy, were retrospectively reviewed. Results: One hundred forty-four patients were eligible for this retrospective analysis; 99 had M0 and 45 M1a disease. The median radiation dose was 50.4 Gy for patients receiving both neoadjuvant and definitive chemoradiotherapy. After a median follow-up of 15 months, the 2-year overall survival for the entire cohort was 45% and 20% in M0 and M1a groups, respectively (p < 0.001). On multivariate analysis, the most significant factors for overall survival were performance status (p < 0.001) and M1a status (p < 0.001). The patients who underwent definitive concomitant chemoradiation had a 2-year overall survival of 36% and 15% in M0 and M1a, respectively (p = 0.03). For patients who underwent neoadjuvant chemoradiation followed by surgery, the 2-year overall survival was 63% and 37% in M0 and M1a, respectively (p = 0.07). Conclusions: M1a status is a strong predictor of poor outcome for patients with cancers of the esophagus or gastroesophageal junction. For patients receiving concurrent chemotherapy and radiation therapy for M1a esophageal cancer, treatment is largely palliative.


Journal of Heart and Lung Transplantation | 2015

The impact of pre-transplant allosensitization on outcomes after lung transplantation

James P. Bosanquet; Chad A. Witt; Bradford Bemiss; Derek E. Byers; Roger D. Yusen; Alexander Patterson; Daniel Kreisel; Thalachallour Mohanakumar; Elbert P. Trulock; Ramsey Hachem

BACKGROUND Allosensitization can be a significant barrier to transplantation for some patients, and previous studies suggested that pre-transplant allosensitization was associated with worse outcomes after lung transplantation. However, human leukocyte antigen (HLA) antibody testing has evolved significantly over the past 10 years, and current assays are highly sensitive and specific. METHODS We examined the impact of pre-transplant allosensitization on post-transplant outcomes in the era of solid-phase multiplex HLA antibody detection assays in this retrospective, single-center study of 304 adult transplant recipients between January 1, 2006, and December 31, 2012. We accepted donor organs for allosensitized patients if a virtual crossmatch was compatible with all previously identified antibodies. RESULTS In univariate and multivariate Cox proportional hazards models, pre-transplant allosensitization, the calculated panel reactive antibody, and the number of pre-transplant HLA antibodies were not associated with the development of acute cellular rejection, lymphocytic bronchiolitis, donor-specific HLA antibodies, chronic lung allograft dysfunction, or graft failure. CONCLUSIONS Pre-transplant allosensitization does not adversely affect outcomes after lung transplantation when the potentially reactive HLAs are avoided in the donor by a virtual crossmatch with the recipient.


The Annals of Thoracic Surgery | 2001

Efficient naked plasmid cotransfection of lung grafts by extended lung/plasmid exposure time

Franco D’Ovidio; Niccolò Daddi; Takashi Suda; Kathleen Grapperhaus; Alexander Patterson

BACKGROUND Multiple gene cotransfection may be an effective strategy to modulate concurrent pathologic events after lung transplantation. We investigated in vivo naked plasmid lung cotransfection during cold preservation and the role of lung parenchyma/naked plasmid exposure time. METHODS F344 rats underwent left main bronchus instillation of pCF1-CAT (chloramphenicol acetyl transferase) (130 microg) +/- pCF1-beta-Gal (beta-galactosidase) (130 microg) in saline. Part Ia: 4 degrees C preservation versus cotransfection. Lung isografts (4 groups, n = 8) were stored after transfection for 1 (2 groups: one received only pCF1-CAT), 6, and 18 hours. Recipient sacrifice was after 48 hours. Part Ib: 4 degrees C preservation versus transgene expression. Rats were sacrificed 48 hours after transfection in a nontransplant setting (2 groups, n = 8; one received only pCF1-CAT). In a third group (n = 8) lungs were harvested 24 hours after transfection, stored for 18 hours, and recipients were sacrificed after 24 hours. The CAT and beta-Gal enzymatic-linked immunosorbent assays were performed. Part II: Lung/plasmid exposure time. In three groups (n = 6) after pCF1-CAT transfection the left main bronchus was not clamped, clamped for 10 minutes, or clamped for 1 hour. Sacrifice was after 48 hours. RESULTS Part Ia: Lung CAT protein was (in picograms per 100 microg of total protein): median, 42 (range, 25 to 95) after 1 hour (only CAT); 67 (19 to 296) after 1 hour, 32 (6 to 157) after 6 hours; and 9 (5 to 243) after 18 hours. Lung beta-Gal protein was (in picograms per 100 microg of total protein): median, 20 (range, 5 to 353) after 1 hour; 17 (6 to 157) after 6 hours; 4 (1 to 74) after 18 hours (1 hour versus 18 hours, p = 0.04 for both proteins). CAT and beta-Gal production were significantly correlated (p = 0.0001, r = 0.924). Part Ib: Lung CAT protein was (in picograms per 100 microg of total protein): median, 2 (range, 0.6 to 10) no transplant, only CAT; 7 (0.3 to 13) no transplant; 3 (0.9 to 14) transplant. Part II: Left lung CAT protein was (in picograms per 100 microg of total protein): median, 31 (range, 6 to 83) no clamp; 74 (25 to 430) 10 minutes of clamp; 111 (30 to 263) 1 hour of clamp. Right lung CAT protein was (in picograms per 100 microg of total protein): median, 0.06 (range, 0 to 0.9) no clamp; 1 (0 to 6) 10 minutes of clamp; 1 (0 to 18) 1 hour of clamp. CONCLUSIONS Efficient lung isograft endobronchial cotransfection results from using naked plasmid. Cold preservation affects transfection efficiency but not transgene expression. Lung parenchyma/naked plasmid exposure time determines transfection efficiency.

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Bryan F. Meyers

Washington University in St. Louis

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Elbert P. Trulock

Washington University in St. Louis

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Thalachallour Mohanakumar

Washington University in St. Louis

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Ramaswamy Govindan

Washington University in St. Louis

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Boone Goodgame

Washington University in St. Louis

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Joel D. Cooper

University of Pennsylvania

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Feng Gao

Washington University in St. Louis

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Ramsey Hachem

Washington University in St. Louis

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T. Mohanakumar

Washington University in St. Louis

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