Emmanuele Abate

A New Technique for Measurement of Pharyngeal pH: Normal Values and Discriminating pH Threshold

IntroductionIdentifying gastroesophageal reflux disease as the cause of respiratory and laryngeal complaints is difficult and depends largely on the measurements of increased acid exposure in the upper esophagus or ideally the pharynx. The current method of measuring pharyngeal pH environment is inaccurate and problematic due to artifacts. A newly designed pharyngeal pH probe to avoid these artifacts has been introduced. The aim of this study was to use this probe to measure the pharyngeal pH environment in normal subjects and establish pH thresholds to identify abnormality.MethodsAsymptomatic volunteers were studied to define the normal pharyngeal pH environment. All subjects underwent esophagram, esophageal manometry, upper and lower esophageal pH monitoring with a dual-channel pH catheter and pharyngeal pH monitoring with the new probe. Analyses were performed at 0.5 pH intervals between pH 4 and 6.5 to identify the best discriminating pH threshold and calculate a composite pH score to identify an abnormal pH environment.ResultsThe study population consisted of 55 normal subjects. The pattern of pharyngeal pH environment was significantly different in the upright and supine periods and required different thresholds. The calculated discriminatory pH threshold was 5.5 for upright and 5.0 for supine periods. The 95th percentile values for the composite score were 9.4 for upright and 6.8 for supine.ConclusionA new pharyngeal pH probe which detects aerosolized and liquid acid overcomes the artifacts that occur in measuring pharyngeal pH with existing catheters. Discriminating pH thresholds were selected and normal values defined to identify patients with an abnormal pharyngeal pH environment.

Recurrence after Esophagectomy for Adenocarcinoma: Defining Optimal Follow-Up Intervals and Testing

BACKGROUND To determine the optimal follow-up strategy after esophagectomy for adenocarcinoma of the esophagus or gastroesophageal junction by evaluating the timing of recurrence and the method that first detected the recurrence. STUDY DESIGN Between 1991 and 2007, 590 patients had an esophagectomy for adenocarcinoma. Recurrence occurred in 233 (40%) and, of those, 174 had complete follow-up at our center with a protocol that consisted of an office visit with CT scans and laboratory studies every 3 months for 3 years, every 6 months for 2 years, and then annually. A subset of patients had PET annually. RESULTS Recurrence in the 174 patients with complete follow-up was systemic in 104 (60%), locoregional/nodal in 51 (30%), and both in 19 (10%). Recurrence was first suspected by symptoms and/or physical examination in 29 patients (17%), by CT scan in 105 (60%), PET in 32 (18%), and by elevated CEA in 8 (5%). Recurrence was detected at a median of 11 months (range 3 to 72 months) and occurred later after esophagectomy alone compared with patients who received neoadjuvant therapy (12 versus 8 months; p = 0.01), but the pattern of recurrence was similar. More than 90% of recurrences were detected within 2 years after neoadjuvant therapy, compared with 3 years after esophagectomy alone. Median survival after recurrence was 7 months and was significantly longer in patients treated for the recurrence (9 versus 3 months; p = 0.001). CONCLUSIONS Frequent early follow-up is appropriate after esophagectomy for adenocarcinoma because >90% of recurrences will occur by 3 years after esophagectomy alone and by 2 years following neoadjuvant therapy. Beyond these time periods, 2% to 3% of recurrences were detected each year, suggesting that annual follow-up is adequate. Survival after recurrence was improved with therapy, confirming the use of careful follow-up in these patients.

Clinical characteristics, biologic behavior, and survival after esophagectomy are similar for adenocarcinoma of the gastroesophageal junction and the distal esophagus

OBJECTIVE The Siewert classification system differentiates between adenocarcinoma of the gastroesophageal junction and that of the distal esophagus. The purpose of this study was to evaluate whether there were differences in the location and prevalence of lymph node metastases, type of recurrence, and survival with these tumors that warrant distinguishing between them in clinical practice. METHODS Records of all patients who underwent resection for adenocarcinoma of the distal esophagus or gastroesophageal junction from 1987 to 2007 were retrospectively reviewed. Based on the endoscopic location of the epicenter of the tumor in relation to the gastroesophageal junction, tumors were categorized in 301 patients as being of the distal esophagus and in 208 as being of the gastroesophageal junction. RESULTS There were no significant differences in age, sex, or body mass index between patients with adenocarcinoma of the distal esophagus or gastroesophageal junction. Patients with adenocarcinoma of the distal esophagus were more likely to have reflux symptoms (75% vs 53%, P < .0001) and peritumoral intestinal metaplasia (73% vs 51%, P < .0001) and be in a surveillance program (54% vs 9%, P = .0005) compared with patients with adenocarcinoma of the gastroesophageal junction. However, the prevalence and location of nodal metastases was similar, and in node-positive patients mediastinal node involvement was present in more than 40% of the patients in each group (distal esophageal adenocarcinoma, 47%; gastroesophageal junction adenocarcinoma, 41%). Survival was similar (5 years: distal esophageal adenocarcinoma, 45%; gastroesophageal junction adenocarcinoma, 38%; P = .14), as was the prevalence and type of recurrence. CONCLUSION The prevalence and distribution of lymph node metastases in patients with adenocarcinoma of the distal esophagus and gastroesophageal junction were similar, and after esophagectomy, there was no difference in overall survival or recurrence. Efforts to differentiate between these tumors are unnecessary, and both are effectively treated with esophagectomy.

Proximal esophageal pH monitoring: improved definition of normal values and determination of a composite pH score.

BACKGROUND Patients with respiratory and laryngeal symptoms are commonly referred for evaluation of reflux disease as a potential cause. Dual-probe pH monitoring is often performed, although data on normal acid exposure in the proximal esophagus are limited because of the small number of normal subjects and inconsistent placement of the proximal pH sensor in relation to the upper esophageal sphincter. We measured proximal esophageal acid exposure using dual-probe pH and calculated a composite pH score in a large number of asymptomatic volunteers to better define normal values. STUDY DESIGN Eighty-one normal subjects free of reflux, laryngeal, or respiratory symptoms were recruited. All had video esophagraphy to exclude hiatal hernia. Esophageal pH monitoring was performed using 1 of 3 different dual-probe catheters with sensors spaced 10, 15, or 18 cm apart. The standard components of esophageal acid exposure were measured, excluding meal periods. A composite pH score for the proximal esophagus was calculated using these components. RESULTS The final study population consisted of 59 (49% male) subjects, with a median age of 27 years. All had normal distal esophageal acid exposure and no hiatal hernia. The 95(th) percentile values for the percent time the pH was < 4 for the total, upright, and supine periods were 0.9%, 1.2%, and 0.4%, respectively. The 95(th) percentile for the number of reflux episodes was 24 and for the calculated proximal esophageal composite pH score was 16.4. CONCLUSIONS In a large population of normal subjects, we have defined the normal values and calculated a composite pH score for proximal esophageal acid exposure. The total percent time pH < 4 was similar to previously published normal values, but the number of reflux episodes was greater.

Delayed Esophagogastrostomy: A Safe Strategy for Management of Patients with Ischemic Gastric Conduit at Time of Esophagectomy

BACKGROUND Ischemia of the gastric conduit remains an important complication of esophagectomy and is associated with an increased risk of anastomotic leak and sepsis. We report a group of patients with multiple comorbid conditions and an ischemic gastric conduit that was successfully managed by a delayed esophagogastrostomy. STUDY DESIGN Between 2000 and 2007, esophagectomy with gastric pullup was performed in 554 patients. In 37 patients (7%), the combination of an ischemic graft and substantial comorbid conditions prompted delayed reconstruction to avoid an immediate esophagogastrostomy. In these patients, the gastric conduit was brought up and secured in the neck, and a cervical esophagostomy was constructed. Subsequently, a delayed esophagogastrostomy was performed through neck incision. Outcomes were analyzed at a median of 22 months (interquartile range [IQR], 13 to 30 months). RESULTS There were 29 male and 8 female patients, with a median age of 65 years (IQR, 58 to 75 years). Thirty-one patients had malignant disease; 12 received neoadjuvant therapy. All 37 patients recovered from their esophagectomy without evidence of ischemic necrosis or fistula from their gastric conduit. In 35 patients, a delayed esophagogastrostomy was performed at a median of 98 days (IQR, 89 to 110 days). At the time of reconstruction, all had well-perfused gastric conduits, and the anastomoses healed without leak, wound infection, or sepsis. A stricture developed in three patients and was treated with dilation. Delayed esophagogastrostomy was never performed in two patients because of development of recurrent malignant disease. CONCLUSIONS Delayed esophagogastrostomy is a safe strategy for management of patients with comorbidities and an ischemic gastric conduit at the time of esophagectomy.

Survival in Lymph Node Negative Adenocarcinoma of the Esophagus after R0 Resection With and Without Neoadjuvant Therapy: Evidence for Downstaging of N Status

BACKGROUND After esophagectomy, many patients who received neoadjuvant therapy have no evidence of lymph node involvement (N0 disease). Whether lymph nodes were initially involved and eradicated by the neoadjuvant therapy (down-staged) or if the nodes were never involved is a subject of debate. To address this issue, we compared clinical outcomes in N0 patients treated with neoadjuvant therapy with outcomes in patients treated with surgery alone. STUDY DESIGN We reviewed records of 100 consecutive patients who underwent R0 esophagectomy for adenocarcinoma with pathologic N0 status. Seventy-five patients were treated by operation alone and 25 received neoadjuvant therapy. Tumor characteristics including length, depth, lymphovascular invasion, and degree of differentiation were compared and longterm survival was assessed by Kaplan-Meier analysis at a median of 46 months (interquartile range 26 to 77 months). RESULTS Tumor characteristics were similar between groups. Recurrence was more common in patients who received neoadjuvant therapy compared with those treated with surgery alone (10 of 25 versus 10 of 75, p=0.0063). Patients with N0 disease after neoadjuvant therapy had a significantly worse survival than patients treated by surgery alone (49% versus 85%, p=0.005). CONCLUSIONS Although neoadjuvant therapy may eradicate lymph node metastases, it does not result in the same outcomes as those achieved in patients with N0 disease treated with surgery alone. The poor clinical outcomes observed in N0 patients after neoadjuvant therapy suggest that they initially had node involvement and were downstaged by eradication of lymph node disease.

Circular stapled pyloroplasty: a fast and effective technique for pyloric disruption during esophagectomy with gastric pull-up.

The necessity of pyloroplasty after esophagectomy and gastric pull-up is debated. Disadvantages of a standard pyloroplasty include the potential for leak, shortening of the length of the graft, and complexity when done during a minimally invasive procedure. The aim of this study is to report our experience with a novel internal pyloroplasty technique using a circular stapler (CS pyloroplasty), which is applicable for both laparoscopic and open esophagectomy. The records of all patients who underwent an esophagectomy with gastric pull-up and pyloroplasty between 2002 and 2007 were reviewed. The CS pyloroplasty was performed through a lesser curve gastrotomy with a 21-mm CS, while the standard pyloroplasty entailed a longitudinal full thickness incision through the pylorus with mucosal closure in the same direction and a Graham patch. A CS pyloroplasty was performed in 144 and a standard pyloroplasty in 133 patients. The median patient age was 66years, and the median follow-up was 17months, and was similar for both types of pyloroplasty. Routine postoperative videoesophagram was significantly more likely to show a delay in contrast transit through the pylorus after standard pyloroplasty (16% standard vs. 8% CS pyloroplasty, P= 0.03). Significantly more patients had postoperative endoscopy after standard pyloroplasty (40% standard vs. 24% CS pyloroplasty, P= 0.004), but the frequency of pyloric dilatation was similar. There were no leaks with either technique. A circular stapled pyloroplasty is as efficacious as a standard pyloroplasty after esophagectomy with gastric pull-up. Potential advantages include the ease and simplicity of the procedure along with virtually no risk of a leak and no graft shortening. The technique is amenable to both open and minimally invasive procedures.

Giant Cell Tumor of the Sternum

Primary giant cell tumors of the chest wall are extremely rare. To date, we believe that there have been no reported cases of sternal giant cell tumors in the thoracic literature. We report a case of an isolated giant cell tumor of the sternum in a 28-year-old man. The mass was resected and the sternum was reconstructed with methyl methacrylate prosthesis and bilateral pectoralis muscle advancement flaps. Excellent functional and aesthetic results were achieved.

Esophageal pH exposure and epithelial cell differentiation

It is proposed that epithelial changes induced by gastroesophageal reflux disease are related to the pH environment of the esophageal lumen. We hypothesized that the various types of esophageal epithelium are associated with specific pH environments that induce their formation. The aim of this study was to compare the luminal pH environment to the histology of the distal esophageal epithelium in patients with gastroesophageal reflux disease. A total of 197 symptomatic patients with increased esophageal acid exposure on 24-hour pH monitoring were grouped according to the histology based on biopsies from the distal esophagus: 17 with squamous epithelium, 126 with cardiac epithelium (CE), and 54 with Barretts epithelium (BE). All were free of Helicobacter pylori infection and monitored off acid suppression therapy. Acid exposure was expressed as the percent of time the luminal pH was at intervals of 0-1, 1-2, 2-3, 3-4, 4-5, 5-6, and 6-7 over a 24-hour period. Patients with BE spent significantly more time at pH intervals 2-3, 3-4, and 4-5 than those with CE. This pattern switched at pH interval 5-6, where patients with cardiac mucosa spent more time than those with BE. Patients with squamous and CE had similar pH exposure at all intervals. Patients with BE have significantly longer exposure time at the pH interval of 2 to 5 compared to those with cardiac and squamous epithelium. This suggests that the exposure of stem cells to a luminal pH between 2 and 5 may trigger the differentiation of CE into intestinalized CE.

T1646 Comparison of Ventilation and Cardiovascular Parameters Between Prone Thoracoscopic and Ivor-Lewis Esophagectomy

Thoracoscopic esophagectomy in the prone position is associated with better surgical ergonomics compared to the left lateral decubitus position due to the effects of gravity pooling blood outside the operative field and the reduced need for lung retraction. The aim of this study was to evaluate the physiological effects of prone thoracoscopic esophagectomy with single-lumen intubation on ventilation, respiratory gas exchange, and cardiovascular parameters. Thirty-two consecutive patients underwent esophagectomy either through a prone thoracoscopic approach or through a right thoracotomic approach. Samples of arterial and central venous blood, as well as ventilation and cardiovascular parameters were obtained at baseline, during induction of anesthesia, throughout the operation, and after extubation. Patients undergoing prone thoracoscopic esophagectomy showed higher oxygenation levels (p < 0.001), and a significantly lower mean pulmonary shunt fraction (p = 0.001). Perioperative hemodynamics remained stable throughout the surgical procedures. Thoracoscopic esophagectomy in the prone position with two-lung ventilation was associated with a significant improvement of global oxygen delivery and a significant reduction of the pulmonary shunt when compared to the Ivor Lewis operation.