Use of Positron Emission Tomography in Surgery Follow-Up of Esophageal Cancer

Introduction  Although the prognosis of patients with esophageal cancer has been improved by extended dissection, the incidence of recurrence still remains high. In esophageal cancer, positron emission tomography (PET) using ¹⁸F-fluorodeoxyglucose (FDG) already demonstrated to be useful for initial staging and monitoring response to therapy. This prospective study compared the ability of FDG-PET and conventional imaging to detect early recurrence of esophageal cancer after initial surgery in asymptomatic patients. Materials and Methods  Between October 2003 and September 2006, 41 patients with esophageal cancer were included in a prospective study after initial radical esophagectomy. FDG-PET, thoracoabdominal computed tomography (CT), abdominal ultrasonography, and endoscopy were performed every 6 months after initial treatment. Results and Discussion  Twenty-three patients had recurrent disease (56%), mostly within the first 6 months after surgery (70%). Despite two false-positive scans due to postoperative changes, FDG-PET was more accurate than CT (91% vs. 81%, p = 0.02) for the detection of recurrence with a sensitivity of 100% (vs. 65%), a specificity of 85% (vs. 91%), and a negative predictive value of 100% on a patient-by-patient-based analysis. For the detection of locoregional recurrence, FDG-PET was more accurate than CT (96.2% vs. 88.9%). FDG-PET was also more accurate than CT for the detection of distant metastases (92.5% vs. 84.9%), especially when involving either bones (100%) or liver (98.1%). A lower sensitivity of FDG-PET (57%) for the early detection of small lung metastases did not affect patient management (accuracy = 92.5%). Conclusion  FDG-PET appears to be very useful for the systematic follow-up of asymptomatic patients after esophagectomy with an initial scan performed 6 months after surgery. Presented at the Forty-sixth Annual Meeting of The European Society of Nuclear Medicine, Athens, Greece, September 30–October 4, 2006 (oral presentation).     

Prevalence and topography of intestinal metaplasia in columnar lined esophagus

OBJECTIVES: Barrett's mucosa is considered as a mosaic of three epithelial types but little is known about the topography of intestinal metaplasia in columnar lined esophagus. The aims of the study were to determine the prevalence of intestinal metaplasia within long and short segments of columnar lined esophagus and to analyze the distribution of the intestinal metaplasia within long segments of Barrett's esophagus. PATIENTS AND METHODS: The study was performed on the initial endoscopy carried out among 112 patients enrolled in an endoscopic surveillance program. Seventy-two patients with columnar mucosa extending more than 3 cm into the esophagus (group I) and 40 patients with a short segment of columnar mucosa (group II) had multiple biopsies according to a standardized protocol. 1163 biopsies were analyzed on the whole: 949 biopsies in group I and 214 biopsies in group II. RESULTS: Intestinal metaplasia was identified among 650 (68.5%) and 50 (23.4%) biopsies in groups I and II respectively (P<10-7). The proportion of biopsies with foci of intestinal metaplasia increased significantly with the length of the columnar mucosa. The diagnosis of Barrett's esophagus was confirmed in 100% of the patients in group I and in 45% of the patients in group II. In long segments of Barrett's esophagus, intestinal metaplasia was more frequently observed in the 2 upper thirds of the columnar mucosa that in the lower third (P<10-7). Detailed mapping of the distribution of epithelial types within the columnar lined esophagus identified three patterns of distribution of intestinal metaplasia within long segments of Barrett's esophagus: unifocal, multifocal and diffuse, in 5%, 56% and 39% of the patients respectively. Dysplasia was present in 15% of patients with long segments of Barrett's esophagus and 11% of patients with short segments (NS). CONCLUSION: The distribution of intestinal metaplasia within columnar lined esophagus is heterogeneous and three distinct patterns can be identified: unifocal, multifocal and diffuse. Considering the risk of sampling error, the current recommendations concerning the biopsy protocols are mandatory until the validation of new techniques such as chromoendoscopy or magnifying endoscopy.     

In vitro study of propamidine isethionate: value in the follow-up of Acanthamoeba amebic keratitis

Propamidine isethionate eye drops is one of the treatments which are used against amebic keratitis with Acanthamoeba. Several strains of Acanthamoeba, having been tested with this drug during several weeks, did show off a resistance. The authors come to the conclusion that in vitro sensitivity must be examined and therapy must be perfect since the beginning.     

Polypoid pseudosarcomatous carcinoma of the esophagus. Report of two cases with favorable outcome after medical treatment]

The authors report two cases of esophageal polypoid pseudosarcoma with favorable outcome after endoscopic and medical treatment. Neither of the two patients could undergo general anesthesia. Endoscopic resection or monopolar electrocoagulation of the tumor was associated with chemotherapy and radiation therapy. A complete response of the tumor was observed in both cases. The two patients were alive and well with no evidence of recurrence or metastasis 3 and 5 years after diagnosis. Immunohistochemical study of those two tumors with monoclonal antibodies to intermediate filaments (keratin and vimentin) suggests duality in the spindle cell component. It may explain the biological behaviour of these particular cancers that have a better prognosis than other types of squamous cell carcinomas of the esophagus.     

Flow-cytometric DNA content analysis of esophageal squamous cell carcinomas

To better understand the mechanisms of esophageal carcinogenesis, abnormalities in DNA content of esophageal squamous cell carcinomas were studied. Cellular DNA content was determined by flow cytometric study of 70 endoscopic biopsy specimens obtained from 26 patients with esophageal squamous carcinoma. High-quality histograms were obtained for 23 patients. Twenty-one patients had at least one aneuploid population in their tumor. In 7 patients, multiple aneuploid peaks were detected. Specimens from 2 patients were diploid. The interpretation of the DNA histograms was difficult in 3 patients; an aneuploid population of cells was probable in 2 of them. A statistically significant relationship was found between the degree of differentiation and DNA content abnormalities in the regions of the tumors that could be evaluated by endoscopic biopsies: well-differentiated carcinomas had diploid or small aneuploid populations containing less than 15% of the cells, whereas DNA histograms of moderately or poorly differentiated carcinomas were characterized by large aneuploid peaks representing 25%-90% of the cells and a higher proliferative fraction. No relationship was found between the size or the stage of the tumor and the DNA content detected in endoscopic biopsy samples. The frequency and the multiplicity of abnormal clones in esophageal squamous carcinomas indicates that this cancer, like esophageal adenocarcinoma, develops an association with an acquired genomic instability that produces abnormal clones of cells, according to the multistep model of neoplastic progression.     

Diffuse EGFR staining is associated with reduced overall survival in locally advanced oesophageal squamous cell cancer

Squamous cell carcinoma of the oesophagus (SCCO) is still a pathology of bad prognosis. Specific therapies are now developed against epidermal growth factor receptor (EGFR), human epidermal growth factor receptor 2, c-kit receptor (CD117), vascular endothelial growth factor (VEGF) and p53 protein. This study was aimed at assessing their expression in a large series of SCCO, as well as their potential therapeutic interest in this pathology. Immunohistochemical expression of these factors was assessed retrospectively in 107 cases of SCCO with primary surgery, as well as their relationships to recurrence, metastasis and overall survival on a long-term follow-up. Human epidermal growth factor receptor 2 and CD117 were expressed in less than 3% of the cases. Epidermal growth factor receptor and p53 were overexpressed in 68.2 and 66.4% of the cases, and VEGF in 38.3%. Epidermal growth factor receptor overexpression was significantly related to vascular invasion (P=0.023). Its diffuse positivity was significantly related in multivariate analysis to higher local recurrence (P=0.006) and lower overall survival (P=0.003), in a subgroup of patients of poor outcome who had received postoperative adjuvant treatment. These results highlight the great potential prognostic and therapeutic interest of evaluating EGFR diffuse positivity in locally advanced SCCO.     

Chronic segmental pancreatitis and the annular pancreas: apropos of a case

In a young patient, stenosis due to annular pancreas was revealed by an attack of pancreatitis. The patient already had segmental chronic pancreatitis. Etiological considerations are proposed, based on an embryological approach with special attention to duct anomalies.