Stereotactic radiosurgery for lung cancer

Lung cancer is the most common cause of cancer death in both men and women in the United States. Anatomic lobectomy is the standard treatment and offers the best results for curative treatment of early stage non-small cell lung cancer (NSCLC). With an aging population, a significant proportion of patients are not surgical candidates at the time of diagnosis. In medically inoperable patients, standard external beam radiation has been offered as treatment, with suboptimal results. Stereotactic radiosurgery (SRS), a term coined by Leksell describes an approach using multiple convergent beams, precise localization with a stereotactic coordinate system, and rigid immobilization. It provides precise delivery of beams from multiple collimated paths which maximizes radiation delivery to the tumor, and minimizes the exposure of normal tissue. Early results with SRS are very encouraging, and prospective trials are underway in our institution and others to evaluate its role in early stage NSCLC. In article we review the role of stereotactic radiosurgery for the treatment of lung cancer.

Results of a phase II multicenter study of minimally invasive esophagectomy (Eastern Cooperative Oncology Group Study E2202)

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Background: The incidence of esophagogastric adenocarcinoma (EAC) is increasing at an alarming rate in the United States. Definitive treatment may require a combination of surgery (esophagectomy), chemotherapy and radiation. Operative mortality rates after esophagectomy have been reported as high as 8–23% (NEJM 2003). Minimally invasive esophagectomy (MIE) may decrease morbidity and mortality. Previous single institution studies have demonstrated successful outcomes with MIE. The primary aim of this cooperative group protocol ECOG 2202 was to assess the feasibility of MIE in a multi-institutional setting. Methods: We conducted a prospective phase II trial with a two-stage design. Thirty-five patients entered the first stage, followed by an interim analysis. Next, the study continued to the second stage and full accrual. The primary endpoint was 30-day mortality. Secondary endpoints included complications, duration of intensive care unit (ICU) stay, lymph node (LN) count and clinical outcomes at 3 years. Results: We entered 106 patients (men 84%; women 22%; median age 64, range 36–83) into the study from 16 institutions in the United States (ECOG, CALGB, ACOSOG). Neoadjuvant chemotherapy was administered in 35 (33%) and radiation in 26 (25%). MIE was performed in 99 patients. Final pathology included high-grade dysplasia (n=11), and EAC (n=88). Complications included an overall 30-day mortality rate of 2% (2/106),. Other major complications included pneumonia (4.9%) and anastomotic leak (7.8%). Median ICU stay was 2 days; median LN count was 20. At a mean follow-up of 19 months, the estimated 3-year overall survival for the entire cohort was 50% (95% Confidence interval 35–65%). Stage specific survival was similar to open series. Conclusions: This phase II study demonstrates that MIE is safe and feasible in a multi-center trial, with low perioperative mortality rate and morbidity. Oncologic outcomes are similar to open esophagectomy. This is the first report of a multicenter trial of minimally invasive esophagectomy.

No significant financial relationships to disclose.

Clinical impact of age on outcomes following anatomic lung resection for stage I non-small cell lung cancer

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Background: There is an increasing body of evidence that anatomic segmentectomy may represent an equivalent approach compared to lobectomy in the management of stage I NSCLC. Comorbidities associated with age may result in improved survival with sublobar resection for stage I cancer in the elderly. We report our single institution experience with segmentectomy vs. lobectomy for stage I non-small cell lung cancer stratified by age. Methods: A total of 232 consecutive anatomic segmentectomies were performed for stage IA (n=137) or IB (n=95) NSCLC from 2002–2007. Lobectomy was performed in 594 patients for stage IA (n=297) and IB (n=295) during the same period. Results of segmental resection were compared with lobectomy, stratified by the following age groups: <60, 60–69, 70–79 and = 80. Primary outcome variables included complications, mortality, recurrence patterns, and survival. Statistical analysis included t-test and Fisher's exact test. Results: Mean age (69.9 vs. 68.2), gender distribution and tumor histology were similar between the segmentectomy and lobectomy groups. There was no significant difference in complications, mortality, recurrence, and overall survival in the younger age groups (Table). Segmentectomy was associated with reduced mortality (7.8% vs. 2.8%) and improved overall 3-year survival (p=0.02) in patients >80 years old. Conclusions: Anatomic segmentectomy can be performed with similar morbidity, mortality, recurrence, and survival compared to lobectomy in stage I lung cancer. This approach may be particularly advantageous in the elderly age group, achieving comparable oncologic outcomes with less mortality and improved overall survival.

[Table: see text]

No significant financial relationships to disclose.

An increased proportion of inflammatory cells express tumor necrosis factor alpha in idiopathic achalasia of the esophagus

Achalasia is a motility disorder characterized by the absence of coordinated peristalsis and incomplete relaxation of the lower esophageal sphincter. The etiology remains unclear although dense inflammatory infiltrates within the myenteric plexus have been described. The nature of these infiltrating cells is unknown. The aim of this study was to evaluate the expression of proinflammatory cytokines - namely, tumor necrosis factor alpha and interleukin-2 - in the distal esophageal muscle in patients with achalasia. Lower esophageal sphincter muscle from eight patients undergoing myotomy or esophagectomy for achalasia of the esophagus were obtained at the time of surgery. Control specimens consisted of similar muscle taken from eight patients undergoing operation for cancer or Barrett's esophagus. The expression of tumor necrosis factor alpha and interleukin-2 were assessed by immunohistochemistry. The total number of inflammatory cells within the myenteric plexus were counted in five high power fields. The percentage of infiltrating cells expressing tumor necrosis factor alpha or interleukin-2 was calculated. Clinical data including demographics, preoperative lower esophageal sphincter pressure, duration of symptoms, and dysphagia score (1 = no dysphagia to 5 = dysphagia to saliva) were obtained through electronic medical records. Statistical comparisons between the groups were made using the unpaired t-test, Fisher's exact test, or Mann-Whitney U test, with a two-tailed P-value less than 0.05 being considered significant. The total number of inflammatory cells was found to be similar between the groups. A significantly higher proportion of inflammatory cells expressed tumor necrosis factor alpha in achalasia as compared with controls (22 vs. 11%; P= 0.02). A similar percentage of infiltrating cells expressed interleukin-2 (40 vs. 41%; P= 0.87). Age, gender, preoperative lower esophageal sphincter pressure, or dysphagia score were not correlated to expression of these cytokines. There was, however, a significant inverse correlation between duration of symptoms and the proportion of inflammatory cells expressing tumor necrosis factor alpha in achalasia (P= 0.007). In conclusion, a higher proportion of infiltrating inflammatory cells expressed tumor necrosis factor alpha in achalasia. Furthermore, this proportion appears to be highest early in the disease process. Further studies are required to more clearly delineate the role of tumor necrosis factor alpha in the pathogenesis of this idiopathic disease.

Molecular detection of occult nodal metastases in esophageal adenocarcinoma

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Introduction: Esophageal adenocarcinoma (EAC) is an aggressive malignancy whose incidence is on the rise. Approximately 40% of patients with N0 disease will recur after theoretically curative surgery, suggesting that in early stage disease, metastatic spread is often undetected by routine pathology. Molecular techniques may more accurately detect micrometastatic spread of EAC, but the correlation between molecular analysis of nodes and prognosis is unknown. Our lab has previously identified and validated 4 markers whose gene expression levels are able to distinguish benign nodes from nodes with metastatic EAC: CK19, CK20, CEA and TACSTD1. We used quantitative real-time RT-PCR to evaluate the expression of these 4 markers in lymph nodes from 68 N0 and 62 N1 EAC patients to see if molecular staging is predictive of a worse clinical outcome. Methods: RNA was isolated from 1456 lymph nodes obtained from 130 patients who underwent resection of EAC. QRT-PCR was used to analyze gene expression for each of the 4 markers. Relative expression of each marker was compared with expression in 53 benign esophageal lymph nodes previously analyzed. Results: Analysis of 778 lymph nodes from 68 pN0 patients identified 71 nodes (9%) from 30 patients (44%) which showed positive expression of at least one marker, indicating occult metastases (and molecular upstaging). Analysis of 678 lymph nodes from 62 pN1 patients revealed 141 nodes (21%) from 40 patients (65%) which had positive expression of at least one marker in nodes that were pathologically negative. In the pathologically positive nodes from N1 patients, there was an encouraging 88% concordance between pathological and molecular analysis. After a median follow-up of 2 years, 13 N0 patients had recurrence of their cancer. Gene expression levels of 3 of the 4 markers (CK20, CEA and TACSTD1) correlated with significantly worse disease-free and overall survival among these N0 patients, with p values <0.05. Conclusion: We have shown that QRT-PCR of 3 independent genetic markers is predictive of significantly worse disease-free and overall survival among node-negative EAC patients by identifying lymph nodes with occult metastatic disease. Further analysis will reveal if the N1 patients with molecularly positive lymph nodes had significantly worse outcomes as well.

No significant financial relationships to disclose.

A pilot study of botulinum toxin injection for the treatment of delayed gastric emptying following esophagectomy

OBJECTIVE

Esophagectomy may lead to impairment in gastric emptying, unless a pyloroplasty or pyloromyotomy is performed. These procedures may be technically challenging during minimally invasive esophagectomy, and they are associated with a small but definable morbidity, such as leakage and dumping syndrome. We sought to determine the results of our early experience with injecting the pylorus with botulinum toxin instead of conventional pyloric drainage.

METHODS

Fifteen patients who had undergone esophagectomy and injection of the pylorus with botulinum toxin were identified. Twelve patients had undergone botulinum toxin injection at the time of minimally invasive esophagectomy, and the remaining three had been treated endoscopically after surgery. The latter three patients had undergone esophagectomy with either no pyloric drainage (n = 2) or an inadequate pyloromyotomy (n = 1), and they presented in the postoperative period with delayed gastric emptying. The adequacy of emptying after injection was assessed by the patients' ability to tolerate a regular diet, a barium swallow, and a nuclear gastric emptying study.

RESULTS

No patient injected with botulinum toxin during esophagectomy developed delayed gastric emptying or aspiration pneumonia in the perioperative period. Eight of these patients underwent a nuclear emptying scan at a median of 4.2 months after surgery, which showed a mean emptying half-life of 100 min. With a median follow-up of 5.3 months, one patient (8%) required reintervention for symptoms of gastric stasis, presumably after the effect of the toxin subsided. All three patients injected postoperatively demonstrated an improvement in symptoms of gastric outlet obstruction and were able to resume a regular diet.

CONCLUSIONS

Injection of the pylorus with botulinum toxin can be performed safely in patients undergoing esophagectomy. Longer-term studies are needed to clarify the efficacy and durability of this technique compared to the accepted procedures of pyloromyotomy or pyloroplasty.

Performance reduction in finger amputees when reaching and operating common control devices: a pilot experimental investigation using a simulated finger disability

This paper reports results of an experimental laboratory investigation to determine if finger amputations (most pervasive upper extremity injury in the United States) result in significant work performance deterioration in tasks requiring operation of common control devices found in industrial settings. Ten male student volunteers from the University of Cincinnati participated in this study. The finger disability simulated was of an extreme nature, and was defined as the loss of four fingers in the preferred hand and the thumb in the nonpreferred hand. While being seated, participants activated 5 types of industrial control devices (a rotary dial, a push button, a toggle switch, a castor wheel, and a rocker switch). The controls were assembled on a device attached to a cylindrical pole, such that the control assembly could move up and down the cylindrical pole. The vertical height of control location (15, 20, and 30 in. from the seat reference point) and angle of control location in vertical plane (0 degree, 45 degrees, 90 degrees, and 135 degrees) were varied in the experiment. Participants also had their torso restrained or unrestrained while reaching and activating controls, in addition to the presence or absence of the simulated disability in each participant. Functional reaches and arm reaches from the wall were measured for participants in the sample to determine the distances at which to place the control pole assembly. If a participant was able to reach the control, the time taken to activate and operate the control was recorded. Overall results indicate that participants took significantly longer (p < 0.05) to activate controls in the presence of the simulated disability. Physical restraint did not significantly alter performance provided the participant was able to reach the control. The type of control and the height of location of the control also significantly affected work performance.

Obesity correlates with gastroesophageal reflux

Thirty morbidly obese patients presenting for bariatric surgery were evaluated for symptomatic and objective evidence of gastroesophageal reflux. Sixteen patients had heartburn while 14 were asymptomatic. All underwent esophageal function testing; manometry was performed in all patients, pH monitoring in 28. Patients with esophageal pH < 4 for more than 5% of observed time weighed more than those with normal acid exposure, 165.2 vs 129.8 kg (P < 0.01), and had significantly higher body mass indices, 56.5 vs 48.3 kg/m2 (P < 0.05). Similarly, morbidly obese patients with abnormal reflux scores weighed significantly more and had greater body mass indices than patients with normal scores (P < 0.05). Lower esophageal sphincter pressure was higher in patients with normal esophageal acid exposure than in those with abnormal findings, 15.5 vs 12.5 mm Hg (P < 0.05). This study demonstrates a correlation between both weight and body mass index with gastroesophageal reflux.

Erythromycin strengthens the defective lower esophageal sphincter in patients with gastroesophageal reflux disease

Motilin induces phase III activity of the gastrointestinal tract. Erythromycin has a motilin-like effect on the stomach and significantly increases the lower esophageal sphincter (LES) pressure in normal volunteers. This investigation was performed to evaluate the effects of erythromycin on esophageal function in patients with gastroesophageal reflux disease (GERD). Esophageal manometry was performed in 10 GERD patients before and after intravenous infusion of 500 mg of erythromycin. Values are expressed as mean +/- SEM. LES pressure increased from 13.9 +/- 2.9 mm Hg at baseline to 28.9 +/- 3.6 mm Hg after infusion of erythromycin (p < 0.01). The duration of contractions in the proximal, middle, and distal esophagus was significantly prolonged from 3.5 +/- 0.4 seconds, 3.8 +/- 0.4 seconds, and 4.1 +/- 0.5 seconds to 4.2 +/- 0.2 seconds, 4.6 +/- 0.5 seconds, and 5.6 +/- 0.6 seconds, respectively, after infusion of erythromycin (p < 0.05 for each comparison). Erythromycin did not effect esophageal body contraction amplitude or velocity, or the upper esophageal sphincter. Serum motilin decreased slightly after the administration of erythromycin. We concluded the following: (1) Erythromycin profoundly stimulates the defective LES in patients with GERD. This appears to be a direct motilin agonist-like effect rather than being mediated by release of endogenous motilin. (2) Erythromycin has less effect on the esophageal body, although it does prolong the duration of esophageal contractions.

Erythromycin, motilin, and the esophagus

BACKGROUND

Motilin induces phase III activity of the gastroesophageal tract. Erythromycin has a motilin-like effect on the stomach, but possible esophageal effects have not been evaluated and are the focus of our investigation.

METHODS

Esophageal manometry was performed in 11 healthy volunteers before and after intravenous infusion of 500 mg erythromycin. Values are expressed as means +/- SEM.

RESULTS

Lower esophageal sphincter (LES) pressure increased from 21.1 +/- 2.6 mm Hg at baseline to 37.5 +/- 3.8 mm Hg after erythromycin infusion (p < 0.0001). Erythromycin did not affect LES length, esophageal body contraction amplitude, duration or velocity, or the upper esophageal sphincter. Serum motilin levels decreased from 96.4 +/- 10.9 pmol/L to 81.8 +/- 10.9 pmol/L (p < 0.01) after erythromycin administration.

CONCLUSIONS

Erythromycin profoundly stimulates the normal human LES. This is a direct motilin agonist-like effect and is not mediated by release of endogenous motilin. Erythromycin has no important effect on the esophageal body or the upper esophageal sphincter.