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Dive into the research topics where Michael Machuzak is active.

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Featured researches published by Michael Machuzak.


Clinical Cancer Research | 2007

A Phase I Clinical Trial of Single-Dose Intrapleural IFN-β Gene Transfer for Malignant Pleural Mesothelioma and Metastatic Pleural Effusions: High Rate of Antitumor Immune Responses

Daniel H. Sterman; Adri Recio; Richard G. Carroll; Colin T. Gillespie; Andrew R. Haas; Anil Vachani; Veena Kapoor; Jing Sun; Richard L. Hodinka; Jennifer L. Brown; Michael J. Corbley; Michael Parr; Mitchell Ho; Ira Pastan; Michael Machuzak; William Benedict; Xin Qiao Zhang; Elaina M. Lord; Leslie A. Litzky; Daniel F. Heitjan; Carl H. June; Larry R. Kaiser; Robert H. Vonderheide; Steven M. Albelda

Purpose: This phase 1 dose escalation study evaluated the safety and feasibility of single-dose intrapleural IFN-β gene transfer using an adenoviral vector (Ad.IFN-β) in patients with malignant pleural mesothelioma (MPM) and metastatic pleural effusions (MPE). Experimental Design: Ad.IFN-β was administered through an indwelling pleural catheter in doses ranging from 9 × 1011 to 3 × 1012 viral particles (vp) in two cohorts of patients with MPM (7 patients) and MPE (3 patients). Subjects were evaluated for (a) toxicity, (b) gene transfer, (c) humoral, cellular, and cytokine-mediated immune responses, and (d) tumor responses via 18-fluorodeoxyglucose-positron emission tomography scans and chest computed tomography scans. Results: Intrapleural Ad.IFN-β was generally well tolerated with transient lymphopenia as the most common side effect. The maximally tolerated dose achieved was 9 × 1011 vp secondary to idiosyncratic dose-limiting toxicities (hypoxia and liver function abnormalities) in two patients treated at 3 × 1012 vp. The presence of the vector did not elicit a marked cellular infiltrate in the pleural space. Intrapleural levels of cytokines were highly variable at baseline and after response to gene transfer. Gene transfer was documented in 7 of the 10 patients by demonstration of IFN-β message or protein. Antitumor immune responses were elicited in 7 of the 10 patients and included the detection of cytotoxic T cells (1 patient), activation of circulating natural killer cells (2 patients), and humoral responses to known (Simian virus 40 large T antigen and mesothelin) and unknown tumor antigens (7 patients). Four of 10 patients showed meaningful clinical responses defined as disease stability and/or regression on 18-fluorodeoxyglucose-positron emission tomography and computed tomography scans at day 60 after vector infusion. Conclusions: Intrapleural instillation of Ad.IFN-β is a potentially useful approach for the generation of antitumor immune responses in MPM and MPE patients and should be investigated further for overall clinical efficacy.


Journal of Thoracic Oncology | 2009

A Comparison of Two Stereotactic Body Radiation Fractionation Schedules for Medically Inoperable Stage I Non-small Cell Lung Cancer: The Cleveland Clinic Experience

K.L. Stephans; T. Djemil; C.A. Reddy; S Gajdos; Matthew Kolar; David P. Mason; Sudish C. Murthy; Thomas W. Rice; Peter J. Mazzone; Michael Machuzak; Tarek Mekhail; Gregory M.M. Videtic

Purpose: To assess the impact of fractionation upon tumor control and toxicity in medically inoperable early stage lung cancer patients treated with stereotactic body radiotherapy. Methods: We reviewed 94 consecutive stereotactic body radiotherapy treatments (86 patients) with medically inoperable stage I non-small cell lung cancer receiving either 50 Gy in five fractions (n = 56) or 60 Gy in three fractions (n = 38) from October 2003 to August 2007. Institutional practice was 10 Gy × 5 before March 1, 2006, when it changed to 20 Gy × 3 to conform to Radiation Therapy Oncology Group 0236 unless otherwise dictated clinically. Results: Median age was 73 years and median Karnofsky performance status 80. A total of 69 lesions were T1, 24 were T2 lung cancer. Median follow-up was 15.3 months. For the 50- and 60-Gy cohorts at 1 year, local control was 97.3% versus 100%, nodal failure 7.3% versus 3.4%, distant metastasis rate 21.8% versus 29.5%, and overall survival 83.1% versus 76.9% (p = 0.68, 0.54, 0.56, and 0.54, respectively). There was no difference in overall survival for patients with histologic (n = 61) compared with radiographic (n = 33) diagnosis. There was no impact of fractionation in the subset of T2 tumors. We observed two cases (2.2%) of clinical grade 2 pneumonitis. Mild late chest wall toxicity (grade 1 or 2) was seen in nine patients (10%) at a median of 8.4 months after treatment and was more common in the 60-Gy group (7 of 38 [18%] versus 2 of 56 [4%], p = 0.028). Conclusions: Local control, overall survival, nodal failure, and distant failure were not affected by fractionation. Chest wall toxicity was more common with 60-Gy group.


Journal of Thoracic Oncology | 2009

Comprehensive Analysis of Pulmonary Function Test (PFT) Changes After Stereotactic Body Radiotherapy (SBRT) for Stage I Lung Cancer in Medically Inoperable Patients

K.L. Stephans; T. Djemil; C.A. Reddy; S Gajdos; Mathew Kolar; Michael Machuzak; Peter J. Mazzone; Gregory M.M. Videtic

Background: To assess for variables predicting pulmonary function test (PFT) changes after stereotactic body radiotherapy (SBRT) for medically inoperable stage I lung cancer. Methods: We reviewed 92 consecutive patients undergoing SBRT for stage I lung cancer between February 2004 and August 2007. A total of 102 lesions were treated using prescriptions of 20 Gy × 3 (n = 40), 10 Gy × 5 (n = 56), and 5 Gy × 10 (n = 6). Institutional practice was 10 Gy × 5 before March 1, 2006 before changing to 20 Gy × 3 to conform to RTOG 0236 unless otherwise dictated clinically. Results: Median pretreatment forced expiratory volume at 1 second (FEV1) was 1.21 liter (50% of predicted) and median diffusion capacity to carbon monoxide (DLCO) was 56.5. There was no significant overall change in PFTs after SBRT. Individual patients experienced both substantial improvements and declines (10% declined at least 14% predicted FEV1% and 19% predicted DLCO). The mean change in FEV1 was −0.05 liter (range, −0.98 to +1.29 liter; p = 0.22) representing −1.88% predicted baseline FEV1 (range, −33 to + 43%; p = 0.62). DLCO declined 2.59% of predicted (range, −37 to +33%; p = 0.27). Conformality index, V5 and V10 were associated with individual patient changes in FEV1% (p = 0.033, p = 0.0036, p = 0.025, respectively), however, correlations were small and overall treatment dose did not predict for changes (p = 0.95). There was no significant difference in FEV1 (p = 0.55) or FEV1% (p = 0.37) changes for central versus peripheral locations. No factors predicted for individual changes in DLCO. Patients with FEV1% below the median of the study population had significantly longer overall survival (p = 0.0065). Although patients dying of cardiac disease died earlier than those dying of other causes, FEV1% below median was not associated with a lower risk of dying of cardiac disease or with lower Charlson comorbidity index. Conclusions: (1) SBRT was well tolerated and PFT changes were minimal. (2) Central lesions were safely treated with 50 Gy.


Respiration | 2010

A Multicenter Pilot Study of a Bronchial Valve for the Treatment of Severe Emphysema

Daniel H. Sterman; Atul C. Mehta; Douglas E. Wood; P. N. Mathur; Robert J. McKenna; D. E. Ost; J. D. Truwit; Philip T. Diaz; Momen M. Wahidi; Robert J. Cerfolio; Roger A. Maxfield; Ali I. Musani; Thomas R. Gildea; F. Sheski; Michael Machuzak; Andrew R. Haas; H. X. Gonzalez; Steven C. Springmeyer

Background: Chronic obstructive pulmonary disease (COPD) affects millions of people and has limited treatment options. Surgical treatments for severe COPD with emphysema are effective for highly selected patients. A minimally invasive method for treating emphysema could decrease morbidity and increase acceptance by patients. Objective: To study the safety and effectiveness of the IBV® Valve for the treatment of severe emphysema. Methods: A multicenter study treated 91 patients with severe obstruction, hyperinflation and upper lobe (UL)-predominant emphysema with 609 bronchial valves placed bilaterally into ULs. Results: Valves were placed in desired airways with 99.7% technical success and no migration or erosion. There were no procedure-related deaths and 30-day morbidity and mortality were 5.5 and 1.1%, respectively. Pneumothorax was the most frequent serious device-related complication and primarily occurred when all segments of a lobe, especially the left UL, were occluded. Highly significant health-related quality of life (HRQL) improvement (–8.2 ± 16.2, mean ± SD change at 6 months) was observed. HRQL improvement was associated with a decreased volume (mean –294 ± 427 ml, p = 0.007) in the treated lobes without visible atelectasis. FEV1, exercise tests, and total lung volume were not changed but there was a proportional shift, a redirection of inspired volume to the untreated lobes. Combined with perfusion scan changes, this suggests that there is improved ventilation and perfusion matching in non-UL lung parenchyma. Conclusion: Bronchial valve treatment of emphysema has multiple mechanisms of action and acceptable safety, and significantly improves quality of life for the majority of patients.


Chest | 2015

Therapeutic Bronchoscopy for Malignant Central Airway Obstruction: Success Rates and Impact on Dyspnea and Quality of Life

David E. Ost; Armin Ernst; Horiana B. Grosu; Xiudong Lei; Javier Diaz-Mendoza; Mark Slade; Thomas R. Gildea; Michael Machuzak; Carlos A. Jimenez; Jennifer Toth; Kevin L. Kovitz; Cynthia Ray; Sara Greenhill; Roberto F. Casal; Francisco Almeida; Momen M. Wahidi; George A. Eapen; David Feller-Kopman; Rodolfo C. Morice; Sadia Benzaquen; Alain Tremblay; Michael Simoff

BACKGROUND There is significant variation between physicians in terms of how they perform therapeutic bronchoscopy, but there are few data on whether these differences impact effectiveness. METHODS This was a multicenter registry study of patients undergoing therapeutic bronchoscopy for malignant central airway obstruction. The primary outcome was technical success, defined as reopening the airway lumen to > 50% of normal. Secondary outcomes were dyspnea as measured by the Borg score and health-related quality of life (HRQOL) as measured by the SF-6D. RESULTS Fifteen centers performed 1,115 procedures on 947 patients. Technical success was achieved in 93% of procedures. Center success rates ranged from 90% to 98% (P = .02). Endobronchial obstruction and stent placement were associated with success, whereas American Society of Anesthesiology (ASA) score > 3, renal failure, primary lung cancer, left mainstem disease, and tracheoesophageal fistula were associated with failure. Clinically significant improvements in dyspnea occurred in 90 of 187 patients measured (48%). Greater baseline dyspnea was associated with greater improvements in dyspnea, whereas smoking, having multiple cancers, and lobar obstruction were associated with smaller improvements. Clinically significant improvements in HRQOL occurred in 76 of 183 patients measured (42%). Greater baseline dyspnea was associated with greater improvements in HRQOL, and lobar obstruction was associated with smaller improvements. CONCLUSIONS Technical success rates were high overall, with the highest success rates associated with stent placement and endobronchial obstruction. Therapeutic bronchoscopy should not be withheld from patients based solely on an assessment of risk, since patients with the most dyspnea and lowest functional status benefitted the most.


Chest | 2015

Complications following therapeutic bronchoscopy for malignant central airway obstruction: Results of the AQuIRE registry

David E. Ost; Armin Ernst; Horiana B. Grosu; Xiudong Lei; Javier Diaz-Mendoza; Mark Slade; Thomas R. Gildea; Michael Machuzak; Carlos A. Jimenez; Jennifer Toth; Kevin L. Kovitz; Cynthia Ray; Sara Greenhill; Roberto F. Casal; Francisco Almeida; Momen M. Wahidi; George A. Eapen; Lonny Yarmus; Rodolfo C. Morice; Sadia Benzaquen; Alain Tremblay; Michael Simoff

BACKGROUND There are significant variations in how therapeutic bronchoscopy for malignant airway obstruction is performed. Relatively few studies have compared how these approaches affect the incidence of complications. METHODS We used the American College of Chest Physicians (CHEST) Quality Improvement Registry, Evaluation, and Education (AQuIRE) program registry to conduct a multicenter study of patients undergoing therapeutic bronchoscopy for malignant central airway obstruction. The primary outcome was the incidence of complications. Secondary outcomes were incidence of bleeding, hypoxemia, respiratory failure, adverse events, escalation in level of care, and 30-day mortality. RESULTS Fifteen centers performed 1,115 procedures on 947 patients. There were significant differences among centers in the type of anesthesia (moderate vs deep or general anesthesia, P < .001), use of rigid bronchoscopy (P < .001), type of ventilation (jet vs volume cycled, P < .001), and frequency of stent use (P < .001). The overall complication rate was 3.9%, but significant variation was found among centers (range, 0.9%-11.7%; P = .002). Risk factors for complications were urgent and emergent procedures, American Society of Anesthesiologists (ASA) score > 3, redo therapeutic bronchoscopy, and moderate sedation. The 30-day mortality was 14.8%; mortality varied among centers (range, 7.7%-20.2%, P = .02). Risk factors for 30-day mortality included Zubrod score > 1, ASA score > 3, intrinsic or mixed obstruction, and stent placement. CONCLUSIONS Use of moderate sedation and stents varies significantly among centers. These factors are associated with increased complications and 30-day mortality, respectively.


Current Opinion in Organ Transplantation | 2010

Anastomotic airway complications after lung transplantation.

Sudish C. Murthy; Thomas R. Gildea; Michael Machuzak

Purpose of reviewAnastomotic airway complications continue to plague recovery after lung transplantation and serve as a major source of morbidity and mortality. Prevalence has surprisingly remained relatively constant over the last decade, despite improvement in overall transplant survival. Recent findingsAnastomotic airway complications occur in about one-fifth of patients following lung transplantation and are formidable and persistent problems. Technical issues associated with complications are difficult to define, but may include telescoping anastomoses and donor–recipient size mismatch. Endobronchial therapy of complications has reduced early mortality, but may not impact the late deleterious consequences of these complications. A therapeutic algorithm has been developed to assist clinicians. SummaryDespite increasing experience, anastomotic airway complications remain problematic. Continued investigation into this process appears warranted, given the impact and prevalence. Very few risk factors currently appear modifiable, however.


Thoracic Surgery Clinics | 2015

Airway complications after lung transplantation.

Michael Machuzak; Jose F. Santacruz; Thomas R. Gildea; Sudish C. Murthy

Airway complications after lung transplantation present a formidable challenge to the lung transplant team, ranging from mere unusual images to fatal events. The exact incidence of complications is wide-ranging depending on the type of event, and there is still evolution of a universal characterization of the airway findings. Management is also wide-ranging. Simple observation or simple balloon bronchoplasty is sufficient in many cases, but vigilance following more severe necrosis is required for late development of both anastomotic and nonanastomotic airway strictures. Furthermore, the impact of coexisting infection, rejection, and medical disease associated with high-level immunosuppression further complicates care.


Journal of bronchology & interventional pulmonology | 2013

Histologic and molecular characterization of lung cancer with tissue obtained by electromagnetic navigation bronchoscopy.

Duc Ha; Humberto Choi; Francisco Almeida; Andrea Arrossi; Jennifer Brainard; Joseph Cicenia; Carol Farver; Thomas R. Gildea; Michael Machuzak; Peter Mazzone

Background:Electromagnetic navigation bronchoscopy (ENB) is a catheter-based adjunct to standard bronchoscopic techniques for the sampling of lung lesions. We sought to evaluate the adequacy of ENB-obtained samples for histologic subtyping of lung cancer, epidermal growth factor receptor (EGFR) mutations, and echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) translocations. Methods:We retrospectively analyzed consecutive patients who underwent ENB for the diagnosis of lung lesions between 2008 and 2011. In those proven to be a primary lung cancer by ENB, tissue adequacy for histologic subtyping was recorded. Accuracy was determined by comparison with resected specimens when available. Tissue adequacy for EGFR mutation and/or EML4-ALK analyses was also reviewed. Results:Sixty-five ENB cases resulted in a diagnosis of lung cancer. Tissues obtained were adequate for histologic subtyping in all 65 cases. Forty-three (66.2%) were diagnosed with adenocarcinoma, 19 (29.2%) with squamous cell carcinoma, 3 (4.6%) with small cell carcinoma. In 51 cases (78.5%), subtyping was performed by morphology alone, whereas 11 (21.5%) required immunohistochemical staining. Sixteen of 65 tumors underwent surgical resection. Concordance of histologic subtyping between ENB and surgical specimens was 87.5% (14 tumors). ENB-obtained samples from 15 patients with adenocarcinoma were sent for EGFR mutation analysis, of which 14 (93.3%) were adequate. Samples from 2 patients were evaluated for EML4-ALK gene rearrangements, both of which were adequate for analysis. Conclusions:ENB is effective at obtaining tissue samples adequate for histologic subtyping, EGFR mutation, and EML4-ALK translocation analysis.


Journal of Bronchology | 2006

Topical Mitomycin C is an Effective, Adjunct Therapy for the Treatment of Severe, Recurrent Tracheal Stenosis in Adults

William Krimsky; Ubaid Ullah Sharief; Daniel H. Sterman; Michael Machuzak; Ali I. Musani

Mitomycin C is a potent fibroblast inhibitor that has been used with some success when applied topically to inhibit the vigorous granulation response noted after airway injury in animal models and pediatric patients. We describe, what we believe to be the first 2 cases of patients treated adjunctively with topical Mitomycin C for severe, recurrent tracheal stenosis as a consequence of prolonged intubation. Our objective was to confirm the results of these findings and to expand the potential indications of this therapy in adults.

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Jose F. Santacruz

Houston Methodist Hospital

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