Evidence-based opioid prescribing guidelines after lung resection: a prospective, multicenter analysis.

Background: Opioid prescribing guidelines have significantly decreased overprescribing and post-discharge use after cardiac surgery; however, limited recommendations exist for general thoracic surgery patients, a similarly high-risk population. We examined opioid prescribing and patient-reported use to develop evidence-based, opioid prescribing guidelines after lung cancer resection. Methods: This prospective, statewide, quality improvement study was conducted between January 2020 to March 2021 and included patients undergoing surgical resection of a primary lung cancer across 11 institutions. Patient-reported outcomes at 1-month follow-up were linked with clinical data and Society of Thoracic Surgery (STS) database records to characterize prescribing patterns and post-discharge use. The primary outcome was quantity of opioid used after discharge; secondary outcomes included quantity of opioid prescribed at discharge and patient-reported pain scores. Opioid quantities are reported in number of 5-mg oxycodone tablets (mean ± standard deviation). Results: Of the 602 patients identified, 429 met inclusion criteria. Questionnaire response rate was 65.0%. At discharge, 83.4% of patients were provided a prescription for opioids of mean size 20.5±13.1 pills, while patients reported using 8.2±13.0 pills after discharge (P<0.001), including 43.7% who used none. Those not taking opioids on the calendar day prior to discharge (32.4%) used fewer pills (4.4±8.1 vs. 11.7±14.9, P<0.001). Refill rate was 21.5% for patients provided a prescription at discharge, while 12.5% of patients not prescribed opioids at discharge required a new prescription before follow-up. Pain scores were 2.4±2.5 for incision site and 3.0±2.8 for overall pain (scale 0-10). Conclusions: Patient-reported post-discharge opioid use, surgical approach, and in-hospital opioid use before discharge should be used to inform prescribing recommendations after lung resection.

The Role of Lung Cancer Surgical Technique on Lymph Node Sampling and Pathologic Nodal Upstaging.

BACKGROUND: The role of operative approach in surgical lymphadenectomies and pathologic nodal upstaging for lung cancer remains unclear. METHODS: This study retrospectively reviewed patients who underwent lobectomy for non-small cell lung cancer from January 2015 to December 2020 at 16 centers within a statewide quality improvement collaborative in Michigan. Patients were stratified by operative approach, and our primary end points were number of LN recovered, number of LN stations sampled, and rates of nodal upstaging with nodal upstaging defined as a higher final pathologic nodal stage compared with preoperative clinical nodal staging. RESULTS: A total of 3036 patients were included: 608 (20.0%) with open lobectomies, 1362 (41.3%) with video-assisted thoracoscopic surgery (VATS), and 1233 (37.4%) with robot-assisted thoracoscopic surgery (RATS) lobectomies. Using multivariable logistic regression, study investigators found that VATS was associated with lower rates of nodal upstaging (odds ratio [OR], 0.71; 95% CI, 0.54-0.94; P = .015) and harvesting ≥10 LNs (OR, 0.40; 95% CI, 0.31-0.50; P < .001) as compared with open surgery, whereas no significant difference was found between RATS and open techniques. Compared with open surgery, VATS had lower rates of sampling at ≥5 nodal stations (OR, 0.66; 95% CI, 0.53-0.84; P = .001), whereas RATS rates were higher (OR, 2.38; 95% CI, 1.85-3.06; P < .001). CONCLUSIONS: VATS lobectomies were associated with lower rates of harvesting ≥10 LNs, sampling ≥5 LN stations, and pathologic nodal upstaging compared with open and RATS lobectomies. Compared with open procedures, RATS lobectomies were associated with higher rates of sampling ≥5 LN stations, but there was no significant difference between open and RATS approaches in rates of nodal upstaging or harvesting ≥10 LNs.

Adequate lung cancer surgery lymphadenectomy within a statewide quality collaborative: Quality improvement in action.

OBJECTIVES: In January 2016, our statewide quality improvement collaborative focused on 3 metrics of adequate lymph node harvest during lung cancer surgery: (1) rates of pathologic examination of 10 lymph nodes or more; (2) sampling 5 or more lymph node stations or more within the hilum or mediastinum; and (3) pathologic nodal upstaging (pathologic nodal stage higher than clinical nodal stage). Unblinded, hospital-level outcomes were presented at biannual meetings, and opportunities for education or improvement were discussed. We set out to describe this quality improvement initiative and the subsequent impact on surgical lymphadenectomies statewide. METHODS: We retrospectively reviewed patients undergoing lobectomy for stage IA to IIIA non-small-cell lung cancer from July 2015 to December 2020 at the 16 participating centers. RESULTS: The study cohort included 3753 patients. The rates of examining 10 lymph nodes or more statewide increased from 215 lobectomies (44.0%) in 2015 to 522 lobectomies (78.9%) in 2020 (P < .001). Similar trends were noted statewide for 5 lymph node stations or more, which increased from 193 lobectomies (39.6%) to 531 lobectomies (80.3%) in 2020 (P < .001). The overall rate of nodal upstaging was more variable year to year and generally declined over time (P = .004). CONCLUSIONS: Our statewide quality improvement initiative improved rates of appropriate lymph node staging for surgically treated non-small cell lung cancer compared with national rates. This work demonstrates the power that a "community of practice" philosophy can have on surgical treatment of lung cancer. Quality improvement interventions including transparent data-driven discussions and collaboration can help guide future quality improvement initiatives and should be readily transferrable to other clinical domains.

Predictors of mortality in nonagenarians undergoing abdominal aortic aneurysm repair: Analysis of the National Surgical Quality Improvement Program dataset.

BACKGROUND: The present study used the American College of Surgeons National Surgical Quality Improvement Program dataset to identify the predictors of 30-day mortality for nonagenarians undergoing endovascular aortic aneurysm repair (EVAR) or open surgical repair (OSR). METHODS: Patients aged >90 years who had undergone abdominal aortic aneurysm repair from 2005 to 2017 were identified using procedure codes. Those with operative times <15 minutes were excluded. The demographics, preoperative comorbidities, and postoperative complications of those who had died by 30 days were compared with those of the patients alive at 30 days. RESULTS: A total of 1356 nonagenarians met the criteria: 1229 (90.6%) had undergone EVAR and 127 (9.4%) had undergone OSR. The overall 30-day mortality was 10.4%. The patients who had died within 30 days were significantly more likely to have undergone OSR than EVAR (40.9% vs 7.2%; P < .001). They also had a greater incidence of dependent functional status (22.0% for those who had died vs 8.1% for those alive at 30 days; P < .001), American Society of Anesthesiology (ASA) classification of ≥4 (81.2% vs 18.8%; P < .001), perioperative blood transfusion (59.6% vs 20.3%; P < .001), postoperative pneumonia (12.1% vs 2.9%; P = .001), mechanical ventilation >48 hours (22.7% vs 2.6%; P < .001), and acute renal failure (12.1% vs 0.5%; P < .001). The EVAR group had a 30-day mortality rate of 2.6% in 1008 elective cases and 28.6% in 221 emergent cases. The OSR group had a 30-day mortality rate of 19.1% in 47 elective cases and 53.7% in 80 emergent cases. In the EVAR cohort, the 30-day mortality group had had a significantly greater incidence of dependent functional status (17% for those who had died vs 8% for those alive at 30 days; P = .004), ASA classification of ≥4 (76.4% vs 40.3%; P < .001), perioperative blood transfusion (57% vs 19%; P < .001), emergency surgery (71% vs 14%; P < .001), and longer operative times (150 vs 128 minutes; P = .001). CONCLUSIONS: Nonagenarians had an incrementally increased, but acceptable, risk of 30-day mortality with EVAR in elective and emergent cases compared with that reported for octogenarians and cohorts of patients not selected for age. We found greater mortality for patients with dependent status, a higher ASA classification, emergent repair, and OSR. These preoperative risk factors could help identify the best surgical candidates. Given these results, consideration for EVAR or OSR might be reasonable for highly selected patients, especially for elective patients with a larger abdominal aortic aneurysm diameter for whom the risk of rupture is higher.

Can the American College of Surgeons National Surgical Quality Improvement Program Risk Calculator Predict Outcomes for Urgent Colectomies?

BACKGROUND: The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) Risk Calculator (RC) predicts postoperative outcomes using 19 risk factors, including operative acuity. Acuity is defined by the calculator as emergent or elective only. The objective of this study is to evaluate the RC's accuracy in urgent (nonelective/nonemergent) cases. METHODS: This is a retrospective review of the NSQIP data for patients who underwent urgent colectomies at a single tertiary care center over a 4-year period. Each urgent case was entered into the RC as both elective and emergent, and predicted outcomes were compared to actual postoperative outcomes. Receiver operating characteristic (ROC) curves were used when sufficient statistical power was present and the area under the curve (AUC) was calculated. RESULTS: A total of 301 urgent colectomy patients were evaluated, representing 19% of all colectomies performed at our institution during the study period. Of the 15 possible postoperative outcomes, the RC showed high predictive value only for mortality (AUC elective .8467; emergent .8451) and discharge to a nursing/rehabilitation facility (AUC elective .8089; emergent .8105). The RC showed no predictive value for 6 outcomes and the remainder lacked statistical power to draw conclusions. DISCUSSION: While the calculator predicted mortality and discharge to a nursing/rehabilitation facility, it did not accurately predict complications for urgent colectomies. Future versions of the calculator should focus on improving the predictive value by including urgent cases as a separate category.

The Society of Thoracic Surgeons General Thoracic Surgery Database 2019 Update on Outcomes and Quality.

The Society of Thoracic Surgeons General Thoracic Surgery Database (STS GTSD) remains the most robust thoracic surgical database in the world, providing participating institutions semiannual risk-adjusted performance reports and facilitating multiple quality improvement initiatives each year. In 2018, the STS GTSD Data Collection Form was substantially revised to acquire the most important variables with the least data manager burden. In addition, a composite quality measure for all pulmonary resections for cancer was developed, and the impact that minimally invasive approaches have on the model was assessed. The 2018 database audit found that the accuracy of the database remains high, ranging from 92.5% to 98.4%. In 2019, the STS GTSD Task Force plans to focus on increasing generalizability of the database, initiating esophagectomy outcome public reporting, and creating customizable real-time dashboards. This review summarizes all national aggregate outcome, quality measurement, and improvement initiatives from the STS GTSD over the past 12 months.

Defining Proficiency for The Society of Thoracic Surgeons Participants Performing Thoracoscopic Lobectomy.

BACKGROUND: Parameters defining attainment and maintenance of proficiency in thoracoscopic video-assisted thoracic surgery (VATS) lobectomy remain unknown. To address this knowledge gap, this study investigated the institutional performance curve for VATS lobectomy by using risk-adjusted cumulative sum (Cusum) analysis. METHODS: Using The Society of Thoracic Surgeons General Thoracic Surgery Database, the study investigators identified centers that had performed a total of 30 or more VATS lobectomies. Major morbidity, mortality, and blood transfusion were deemed primary outcomes, with expected incidence derived from risk-adjusted regression models. Acceptable and unacceptable failure rates for outcomes were set a priori according to clinical relevance and informed by regression model output. RESULTS: Between 2001 and 2016, 24,196 patients underwent VATS lobectomy at 159 centers with a median volume of 103 (range, 30 to 760). Overall rates of operative mortality, major morbidity, and transfusion were 1% (244 of 24,189), 17.1% (4,145 of 24,196), and 4% (975 of 24,196), respectively. Of the highest-volume centers (≥100 cases), 84% (65 of 77) and 82 % (63 of 77) (p = 0.48) were proficient by major morbidity standards by their 50th and 100th cases, respectively. Similarly, 92% (71 of 77) and 90% (69 of 77) (p = 0.41) of centers showed proficiency by transfusion standards by their 50th and 100th cases, respectively. Three performance patterns were observed: (1) initial and sustained proficiency, (2) crossing unacceptability thresholds with subsequent improved performance; and (3) crossing unacceptability thresholds without subsequent improved performance. CONCLUSIONS: VATS lobectomy outcomes have improved with lower mortality and transfusion rates. The majority of high-volume centers demonstrated proficiency after 50 cases; however, maintenance of proficiency is not ensured. Cusum provides a simple yet powerful tool that can trigger internal audits and performance improvement initiatives.

Predictors of readmission in nonagenarians: analysis of the American College of Surgeons National Surgical Quality Improvement Project dataset.

BACKGROUND: Increased longevity has led to more nonagenarians undergoing elective surgery. Development of predictive models for hospital readmission may identify patients who benefit from preoperative optimization and postoperative transition of care intervention. Our goal was to identify significant predictors of 30-d readmission in nonagenarians undergoing elective surgery. METHODS: Nonagenarians undergoing elective surgery from January 2011 to December 2012 were identified using the American College of Surgeons National Surgical Quality Improvement Project participant use data files. This population was randomly divided into a 70% derivation cohort for model development and 30% validation cohort. Using multivariate step-down regression, predictive models were developed for 30-d readmission. RESULTS: Of 7092 nonagenarians undergoing elective surgery, 798 (11.3%) were readmitted within 30 d. Factors significant in univariate analysis were used to develop predictive models for 30-d readmissions. Diabetes (odds ratio [OR]: 1.51, 95% confidence interval [CI]: 1.24-1.84), dialysis dependence (OR: 2.97, CI: 1.77-4.99), functional status (OR: 1.52, CI: 1.29-1.79), American Society of Anesthesiologists class II or higher (American Society of Anesthesiologist physical status classification system; OR: 1.80, CI: 1.42-2.28), operative time (OR: 1.05, CI: 1.02-1.08), myocardial infarction (OR: 5.17, CI: 3.38-7.90), organ space surgical site infection (OR: 8.63, CI: 4.04-18.4), wound disruption (OR: 14.3, CI: 4.80-42.9), pneumonia (OR: 8.59, CI: 6.17-12.0), urinary tract infection (OR: 3.88, CI: 3.02-4.99), stroke (OR: 6.37, CI: 3.47-11.7), deep venous thrombosis (OR: 5.96, CI: 3.70-9.60), pulmonary embolism (OR: 20.3, CI: 9.7-42.5), and sepsis (OR: 13.1, CI: 8.57-20.1), septic shock (OR: 43.8, CI: 18.2-105.0), were included in the final model. This model had a c-statistic of 0.73, indicating a fair association of predicted probabilities with observed outcomes. However, when applied to the validation cohort, the c-statistic dropped to 0.69, and six variables lost significance. CONCLUSIONS: A reliable predictive model for readmission in nonagenarians undergoing elective surgery remains elusive. Investigation into other determinants of surgical outcomes, including social factors and access to skilled home care, might improve model predictability, identify areas for intervention to prevent readmission, and improve quality of care.

Use of the da Vinci minimally invasive robotic system for resection of a complicated paraspinal schwannoma with thoracic extension: case report.

BACKGROUND AND IMPORTANCE: Applications of robotics to minimally invasive spine surgery have produced several benefits while sparing patients the morbidity of traditional open surgery. Minimally invasive spine surgery offers the advantages of less pain and less blood loss, along with quicker recovery and shorter hospital stays. The da Vinci robotic surgical system has recently been adapted to neurosurgical applications. This article details a posterior approach using a tubular retraction system in conjunction with an anterior approach using the da Vinci robot to completely remove large spinal schwannomas with intrathoracic extension. This technique is an example of a novel application of existing technology initially developed for other applications. CLINICAL PRESENTATION: Two patients with large thoracic schwannomas extending into the chest cavity are reviewed. We present images and video of the combined minimally invasive approach used to completely remove the lesions without complications. CONCLUSION: This report describes a novel neurosurgical application of an existing minimally invasive robotic surgical system.

Surfacing safety hazards using standardized operating room briefings and debriefings at a large regional medical center.

BACKGROUND: Briefings and debriefings, previously shown to be a practical and feasible strategy to improve interdisciplinary communication and teamwork in the operating room (OR), was then assessed as a strategy to prospectively surface clinical and operational defects in surgical care--and thereby prevent patient harm. METHODS: A one-page, double-sided briefing and debriefing tool was used by surgical teams during cases at the William Beaumont Hospital Royal Oak (Royal Oak, Michigan) campus to surface clinical and operational defects during the study period (October 2006-May 2010). Defects were coded into six categories (with each category stratified by briefing or debriefing period) during the first six months, and refinement of coding resulted in expansion to 16 defect categories and no further stratification. A provider survey was used in January 2008 to interview a sample of 40 caregivers regarding the perceived effectiveness of the tool in surfacing defects. FINDINGS: The teams identified a total of 6,202 defects--an average of 141 defects per month--during the entire study period. Of 2,760 defects identified during the six-defect coding period, 1,265 (46%) surfaced during briefings, and the remaining 1,495 (54%) during debriefings. Equipment (48%) and communication (31%) issues were most prominent. Of 3,442 defects identified during the 16-defect coding period, the most common were Central Processing Department (CPD) instrumentation (22%) and Communication/Safety (15%). Overall, 70 (87%) of the 80 responses were in agreement that briefings were effective for surfacing defects, as were 59 (76%) of the 78 responses for debriefings. CONCLUSIONS: Briefings and debriefings were a practical and effective strategy to surface potential surgical defects in the operating rooms of a large medical center.

Benign post-esophagectomy gastrocardiac fistula.

The development of a gastrocardiac fistula is a rare complication following retrosternal gastric conduit creation. We report a case of a 64-year-old male who presented three years after esophagectomy with massive hematemesis. A fistulous connection between his gastric conduit and right ventricle was identified and successfully treated. Although the patient had an atypical presentation and lacked most of the commonly cited risk factors, the combination of peptic ulcer disease and Candida overgrowth resulted in the formation of a gastrocardiac fistula. Adherence to treatment principles including prompt surgical intervention, adequate coverage of the repair, and antimicrobial therapy against Candida species provides the highest likelihood of success in addressing this potentially lethal disease process.

Feeding jejunostomy tubes placed during esophagectomy: are they necessary?

BACKGROUND: Jejunostomy tubes (JT) are routinely placed at the time of esophagectomy and can be associated with low--but not insignificant--morbidity. Increased emphasis on evidence-based medicine prompted this critical review of JT use during esophagectomy and factors that predict the absolute need for JT. METHODS: All esophagectomies performed at one tertiary care institution from 1995 through 2009 were retrospectively reviewed. Statistical analyses were performed to determine preoperative variables that would assist in selecting patients who should receive a JT. RESULTS: A total of 143 JTs were placed in 151 patients undergoing esophagectomy for carcinoma (83.4%), high-grade dysplasia (13.2%), and perforation (2.6%). Of these, 110 patients (76.9%) had returned to oral intake before discharge (median, 7 days), whereas 33 patients (23.1%) still required tube feedings. Of 8 patients who did not undergo intraoperative JT placement, 6 had resumed oral intake at discharge. Two patients were discharged on total parenteral nutrition. Logistic regression analysis of preoperative variables showed a body mass index of less than 18.5 kg/m2 conferred a likelihood of requiring a JT at discharge (odds ratio, 7.56; p<0.05). Age, sex, albumin level, type of esophagectomy, histology, stage, preoperative neoadjuvant therapy, and type of cancer were not significant predictors of JT need at discharge. CONCLUSIONS: The only absolute indication for JT placement after esophagectomy was a body mass index of less than 18.5 kg/m2. Other patients may have selective JT placement based on the surgeon's judgment.

Nonoperative management of postintubation tracheal injuries.

Tracheobronchial rupture is a rare but potentially lethal complication. We present 2 patients with postintubation tracheobronchial rupture who were successfully treated nonoperatively. Goals when treating such patients should include early recognition, appropriate antibiotic coverage, careful selection of operative candidates, and proper endotracheal tube and ventilator management. When treated properly, patients with tracheobronchial rupture can make a full recovery without the need for surgical intervention.

Age, tumor size, type of surgery, and gender predict survival in early stage (stage I and II) non-small cell lung cancer after surgical resection.

BACKGROUND: Even after presumably curative resection the 5-year survival rates are only 60-80% in stage I and 40-50% in stage II NSCLC. Purpose of the present study was the identification of independent clinico-pathological predictors of their survival. METHODS: A retrospective review of 519 consecutive subjects who had undergone attempted curative resection for stage I or II NSCLC was performed. Patients who had received any adjuvant or neo-adjuvant chemo- or radiation therapy were excluded. Primary outcome measure was the duration of overall survival. RESULTS: Median survival was 7.25 years for stage IA, 5.71 years for stage IB and 3.85 years for stage IIB. In univariate analysis, six variables were significantly associated (p-value<0.05) with poorer survival: older age, larger size of the tumor, male gender, surgery other than lobectomy, squamous histology and later stages (stage IB and IIB). In multivariate analysis, age (Hazard ratio=1.06 per year increase in age; p<0.0001), larger tumor size (Hazard ratio=1.54 per doubling of tumor size; p<0.0001), type of surgery (Hazard ratio=1.50 for surgery other than lobectomy; p=0.036), and gender (Hazard ratio=1.45 for male gender; p=0.039) were the predictors of overall survival. CONCLUSIONS: In surgically treated early stage (I and II) NSCLC patients, age, tumor size, type of surgery, and gender are the important predictors of survival.

Implementing standardized operating room briefings and debriefings at a large regional medical center.

BACKGROUND: Effective communication and teamwork are critical in many health care settings, particularly the operating room (OR). Several studies have implicated failures of communication and teamwork as the root cause in a high proportion of sentinel events in the OR. METHODS: In a prospective cohort study at a high-volume teaching, research, and tertiary care referral hospital, a standardized one-page briefing and debriefing tool was developed and implemented in October 2006 to improve interdisciplinary communication and teamwork in the OR. The briefing portion of the tool was completed by the surgical team after the patient's final positioning and before incision; the debriefing portion was initiated and completed by the circulating nurse after the first counts were conducted. Compliance was calculated as the number of cases where the briefing and debriefing tool was completed divided by the total number of eligible cases. Surveys (n=40) were conducted to elicit caregiver perceptions of interdisciplinary communication and teamwork in the OR and the burden and average time taken to complete the briefing and debriefing tool. RESULTS: Between October 2006 and March 2008, 37,133 briefings and debriefings were conducted. Average compliance varied over time since implementation, with overall compliance ranging from 76% to 95%. The majority of caregivers perceived that the briefing and debriefing tool improved interdisciplinary communication and teamwork. On average, it took 2.9 minutes (range, 1-5 minutes) to complete the briefing portion of the tool and 2.5 minutes (range, 1-5 minutes) to complete the debriefing portion. DISCUSSION: Implementation of a standardized briefing and debriefing tool in a large regional medical center was a, practical and feasible strategy to improve perceptions of interdisciplinary communication and teamwork in the OR.

The safe transition from open to thoracoscopic lobectomy: a 5-year experience.

BACKGROUND: We hypothesized that established thoracic surgeons without formal minimally invasive training can learn thoracoscopic lobectomy without compromising patient safety or outcome. METHODS: Data were retrospectively collected on patients who underwent pulmonary lobectomy at a single health system between August 1, 2003, and April 1, 2008. Age, sex, pulmonary function tests, preoperative and postoperative stages, pathologic diagnosis, anatomic resection, extent of lymph node sampling, surgical technique and duration, complications, blood loss, transfusion requirement, chest tube duration, length of hospital stay, 30-day readmission, and mortality rate were examined. The percentage of patients who underwent thoracoscopic lobectomy and their outcomes were then compared among three chronologic cohorts. RESULTS: Three hundred sixty-four patients underwent pulmonary lobectomy (239 open; 99 thoracoscopic; 26 thoracoscopic converted to open). Baseline characteristics, staging, pathologic diagnosis, and anatomic resections were similar in the early, middle, and late cohorts. The percentage of thoracoscopic lobectomies increased from 16% to 49%, whereas open lobectomy decreased from 81% to 42% (p < 0.0001). The complication rate remained constant with the exception of air leaks lasting more than 7 days (9% versus 10% versus 2%; p = 0.02). Hospital length of stay (6 versus 5 versus 4 days; p < 0.0001) and chest tube duration (4 versus 3 versus 3 days; p < 0.0001) decreased and operative duration increased as more thoracoscopic lobectomies were performed. Blood loss, transfusion requirement, 30-day readmission, and 1-year survival were not significantly different among chronologic cohorts. CONCLUSIONS: Established thoracic surgeons can safely incorporate thoracoscopic lobectomy with no increase in morbidity or mortality.

Clinicopathologic analysis of microscopic extension in lung adenocarcinoma: defining clinical target volume for radiotherapy.

PURPOSE: To determine the gross tumor volume (GTV) to clinical target volume margin for non-small-cell lung cancer treatment planning. METHODS: A total of 35 patients with Stage T1N0 adenocarcinoma underwent wedge resection plus immediate lobectomy. The gross tumor size and microscopic extension distance beyond the gross tumor were measured. The nuclear grade and percentage of bronchoalveolar features were analyzed for association with microscopic extension. The gross tumor dimensions were measured on a computed tomography (CT) scan (lung and mediastinal windows) and compared with the pathologic dimensions. The potential coverage of microscopic extension for two different lung stereotactic radiotherapy regimens was evaluated. RESULTS: The mean microscopic extension distance beyond the gross tumor was 7.2 mm and varied according to grade (10.1, 7.0, and 3.5 mm for Grade 1 to 3, respectively, p < 0.01). The 90th percentile for microscopic extension was 12.0 mm (13.0, 9.7, and 4.4 mm for Grade 1 to 3, respectively). The CT lung windows correlated better with the pathologic size than did the mediastinal windows (gross pathologic size overestimated by a mean of 5.8 mm; composite size [gross plus microscopic extension] underestimated by a mean of 1.2 mm). For a GTV contoured on the CT lung windows, the margin required to cover microscopic extension for 90% of the cases would be 9 mm (9, 7, and 4 mm for Grade 1 to 3, respectively). The potential microscopic extension dosimetric coverage (55 Gy) varied substantially between the stereotactic radiotherapy schedules. CONCLUSION: For lung adenocarcinomas, the GTV should be contoured using CT lung windows. Although a GTV based on the CT lung windows would underestimate the gross tumor size plus microscopic extension by only 1.2 mm for the average case, the clinical target volume expansion required to cover the microscopic extension in 90% of cases could be as large as 9 mm, although considerably smaller for high-grade tumors. Fractionation significantly affects the dosimetric coverage of microscopic extension.

Lysyl oxidase expression in bronchogenic carcinoma.

BACKGROUND: Lysyl oxidase catalyzes a key step in the cross-linking of collagen and elastin in the extracellular matrix. Recent studies have documented differential lysyl oxidase expression in the stromal reaction to colon, breast, prostate, and lung cancer. The present study was undertaken to test the hypothesis that lysyl oxidase mRNA and protein expression decrease with advancing tumor stage in patients with bronchogenic carcinoma. METHODS: Tumor specimens were obtained from 17 patients undergoing resection for bronchogenic carcinoma. Real-time polymerase chain reaction was used to determine steady-state lysyl oxidase mRNA expression, and protein expression was qualitatively assessed by immunohistochemistry. RESULTS: Real-time polymerase chain reaction studies documented a 3.4-fold graded decrease in lysyl oxidase mRNA levels as tumors progressed from stage I to IV. Similar qualitative changes in lysyl oxidase protein expression were demonstrated by immunohistochemistry. CONCLUSIONS: These results support the hypothesis that variations in lysyl oxidase expression may correlate with the invasive and metastatic potential of bronchogenic carcinoma.

Wedge resection margin distances and residual adenocarcinoma in lobectomy specimens.

We studied 31 T1 N0 M0 peripheral adenocarcinomas diagnosed by wedge resection and treated by lobectomy. Factors recorded were pleural surface-based, gross cut-surface, and microscopic margin distances; morphologic features of the adenocarcinomas; microscopic extension distance of beyond gross perimeter of neoplasm; and presence of residual adenocarcinoma in the lobectomy specimen. All staple-line margins in the wedge and lobectomy specimens underwent complete histologic examination. The mean pleural surface-based, gross cut-surface, and microscopic margin distances in wedge resections were 13.1, 4.1, and 2.3 mm, respectively. The mean microscopic wedge resection margin distance was 11 mm smaller than the pleural surface-based measured margin. The mean microscopic lepidic growth beyond the gross perimeter of the neoplasm was 7.4 mm. Fourteen lobectomy specimens (45%) included adenocarcinoma. The mean microscopic wedge resection specimen margin distances in cases with and without residual adenocarcinoma in the lobectomy specimens were 0.7 and 2.4 mm, respectively (P < .001). Incomplete excision may contribute to higher locoregional recurrence rates following limited resection surgery. Two processes affected wedge resection margin distances: stapling-induced parenchymal stretching, resulting in overestimation of pleural surface-based distances, and microscopic extension of adenocarcinoma beyond the gross perimeter of the neoplasm.