Evaluation of minimally invasive surgical staging for esophageal cancer

Minimally invasive staging of esophageal cancer

Esophageal cancer is one of the most common malignancies in the world today and the sixth-leading cause of cancer-related mortality. Accurate preoperative staging of esophageal cancer is imperative to the selection of appropriate treatments. Patients with esophageal carcinomas typically undergo a multimodality staging process including noninvasive imaging techniques, such as computed tomography (CT) and positron emission tomography (PET), as well as endoscopic ultrasound (EUS), which is slightly more invasive. Minimally invasive surgical staging, with laparoscopy, occasionally in combination with video-assisted thoracoscopy, is used in the staging process at select institutions and has been shown to be more accurate than noninvasive staging modalities. Two major advantages of minimally invasive surgical staging over conventional techniques are the improved assessment of locoregional disease and enhanced identification of distant metastases. These advantages decrease the likelihood that the patient will undergo a nontherapeutic laparotomy. Currently, no clear consensus exists regarding which patients with esophageal cancer would benefit most from the addition of minimally invasive surgical staging. We have, however, found that minimally invasive surgical staging with laparoscopy is particularly valuable in detection of occult distant metastases. In this article, we summarize the staging modalities for esophageal cancer including minimally invasive surgical staging.

Vascular conditioning of the stomach before esophageal reconstruction by gastric interposition

Gastric interposition with intrathoracic or cervical esophagogastrostomy is currently the preferred operation for reconstruction after esophagectomy. Anastomotic leaks however result from poor vascular supply to the proximal stomach. They are responsible for significant morbidity and mortality. 'Ischemic conditioning' of the interposed stomach has been proposed as a technique where the 'delay phenomenon' aims at improving the microcirculation of the gastric conduit and preventing anastomotic leakage. Experimental observations and clinical studies have been conducted to document the immediate effects and results of this approach. The aim of this work is to review the principles, pathophysiology, experimental, and clinical evidence related to vascular conditioning of the stomach prior to esophagectomy with gastric interposition and esophagogastric anastomosis. MEDLINE and PubMed were searched to identify articles related to vascular conditioning of the stomach. Cross references were added and reviewed to complete the reference list. The anatomic basis of ischemic conditioning, the prevalence of ischemic events on the gastric conduit, the methodology to assess the microcirculation before and after gastric devascularization, animal experiments, and clinical studies reported on this approach were reviewed. Ten experimental works, eleven clinical observations, four reviews, and two editorial commentaries addressing ischemic conditioning of the stomach were identified and reviewed. Experimental observations document improved microcirculation to the proximal stomach following partial gastric devascularization. Clinical reports show the feasibility and relative safety of gastric ischemic conditioning. Preliminary observations suggest potential improvements to the gastric microcirculation resulting from gastric ischemic conditioning. This approach may help prevent complications at the esophagogastric anastomosis. The actual level of evidence however cannot promote its use outside of clinical research protocols.

Staging Accuracy of Endoscopic Ultrasound Based on Pathologic Analysis after Minimally Invasive Esophagectomy

Endoscopic ultrasonography (EUS) is a common staging modality used in patients with esophageal cancer. The objective of this analysis was to evaluate the accuracy and sensitivity of EUS in determining the depth of penetration (T stage) and nodal status (N stage) in patients with esophageal cancer who underwent minimally invasive esophagectomy (MIE). A retrospective analysis of all patients at a university hospital who underwent preoperative EUS followed by MIE for cancer was performed. We compared the results of preoperative EUS to final pathologic analyses of the esophageal specimen, examining the accuracy of EUS staging. Ninety-five patients with esophageal cancer who underwent MIE had preoperative EUS. Twenty-four of the 95 patients were excluded for lack of a repeat EUS after neoadjuvant therapy before resection. Hence, 71 patients were evaluated for the accuracy of EUS staging. The accuracy of EUS for TO disease was 80 per cent; T1 disease was 75 per cent; T2 disease was 39 per cent; and T3 disease was 88 per cent. The overall EUS accuracy for T stage was 72 per cent with overstaging occurring mostly for pathologic T1 tumors in 18 per cent and understaging occurring mostly for pathologic T3 tumors in 11 per cent. The sensitivity and specificity for detection of nodal involvement were 79 per cent and 74 per cent, respectively. However the accuracy for T and N staging by EUS after neoadjuvant therapy decreased to 63 per cent and 38 per cent, respectively. Endoscopic ultrasound in the absence of neoadjuvant therapy is a relatively accurate and sensitive modality for determining the depth of tumor penetration and the presence of nodal disease in patients with esophageal carcinoma. The accuracy for T and N staging is less reliable after neoadjuvant therapy.

Laparoscopic Gastric Ischemic Conditioning Prior to Esophagogastrectomy: Technique and Review

Esophagectomy can be associated with significant peri-operative morbidity such as leaks and strictures. Gastric ischemia as a result of gastric devascularization is one of the several contributing factors that may play a role in development of these complications. In an attempt to improve gastric tissue perfusion, a technique of gastric ischemic conditioning was proposed. For patients with esophageal cancer and at the time of laparoscopic staging, partial gastric devascularization is achieved by division of the left gastric vessels. Esophagectomy is subsequently performed several days after the gastric ischemic conditioning procedure. Our experience showed that preoperative ligation of left gastric vessels prior to esophagogastrectomy is technically feasible and safe and may decrease ischemic complications such as leaks and strictures.

Preoperative laparoscopic ligation of the left gastric vessels in preparation for esophagectomy

Anastomotic leak is a major cause for morbidity after esophagectomy. The cause is believed to be ischemia of the gastric conduit. Preoperative embolization of the left gastric vessels in preparation for esophagectomy has been shown to improve collateral blood flow of the gastric conduit and may reduce the frequency of anastomotic dehiscence after esophagectomy. This report describes the technique of laparoscopic division of the left gastric vessels in 9 patients who underwent pre-esophagectomy staging laparoscopy. Our initial experience demonstrates that laparoscopic ligation of the left gastric artery is a safe alternative to embolization and can be performed in conjunction with staging laparoscopy for patients with esophageal cancer.

Staginglaparoskopie in der Onkologie

The availability of more treatment options for gastrointestinal cancer requires precise and reliable pretherapeutic staging. Despite impressive technical progress in modern imaging procedures, this high level of staging quality is not yet warranted in all instances. Visual exploration of the abdominal cavity in extended diagnostic laparoscopy (EDL), including surgical dissection of areas which are primarily inaccessible, biopsy retrieval, and laparoscopic ultrasound, is superior in the diagnostic workup of early peritoneal carcinomatosis and (small) liver metastases. It is helpful to evaluate lymph node infliction and local resectability. In esophageal carcinoma, pretherapeutic EDL is valuable in case of advanced adenocarcinoma of the distal esophagus (AEG I according to Siewert), whereas the incidence of abdominal tumor manifestations in squamous cell carcinoma is too low to perform staging laparoscopy. In advanced gastric cancer, EDL yields relevant additional information in up to 20% of cases. If a multimodal therapeutic strategy is considered, EDL should be obligatory at least in prospective therapeutic studies. In carcinoma of the pancreas, EDL is in general not recommended by the majority of centers. Selective use (in particular in advanced cancer with a high probability of local irresectability) is gaining importance. In hepatobiliary malignancy including colorectal metastases, the high yield of additional information by EDL was confirmed in recent studies.

Immediate preoperative laparoscopic staging for squamous cell carcinoma of the esophagus

BACKGROUND

Conventional preoperative staging for esophageal carcinoma could be inaccurate. Laparoscopy has been applied for the staging of various upper gastrointestinal malignancies. It can identify peritoneal and liver deposits not shown by imaging, and could reduce the number of nontherapeutic laparotomies. This study aimed to evaluate the efficacy of laparoscopic staging for the management of squamous cell carcinoma involving the mid and distal esophagus.

METHODS

A retrospective review was performed for all patients with esophageal cancer evaluated for surgical resection from January 1998 to January 2004. Laparoscopy was performed for all the patients with mid and distal esophageal cancer immediately before open gastric mobilization. The efficacy of laparoscopy for the management of squamous cell carcinoma of the esophagus was evaluated.

RESULTS

Among the 63 patients with potentially resectable disease shown on conventional imaging, 54 (84%) underwent esophagectomy with curative intent after laparoscopic staging. Seven patients (11%) underwent laparoscopy alone because of abdominal metastases (n = 5) or other medical conditions (n = 2) that precluded esophagectomy. Two patients (3%) had exploratory right thoracotomy without esophagectomy despite normal laparoscopic findings. The sensitivity and specificity of laparoscopic staging were 100% in this series of patients (100% sensitivity and specificity means no false-positives or -negatives).

CONCLUSION

Laparoscopic staging is valuable for the management of patients with mid and distal squamous cell carcinoma of the esophagus. Patients with metastatic disease and those with prohibitive surgical risk can thus avoid unnecessary laparotomy and be offered other treatment methods.

Multiple management modalities in esophageal cancer: epidemiology, presentation and progression, work-up, and surgical approaches

Annually, approximately 13,200 people in the U.S. are diagnosed with esophageal cancer and 12,500 die of this malignancy. Of new cases, 9,900 occur in men and 3,300 occur in women. In part I of this two-part series, we explore the epidemiology, presentation and progression, work-up, and surgical approaches for esophageal cancer. In the 1960s, squamous cell cancers made up greater than 90% of all esophageal tumors. The incidence of esophageal adenocarcinomas has risen considerably over the past two decades, such that they are now more prevalent than squamous cell cancer in the western hemisphere. Despite advances in therapeutic modalities for this disease, half the patients are incurable at presentation, and overall survival after diagnosis is grim. Evolving knowledge regarding the etiology of esophageal carcinoma may lead to better preventive methods and treatment options for early stage superficial cancers of the esophagus. The use of endoscopic ultrasound and the developing role of positron emission tomography have led to better diagnostic accuracy in this disease. For years, the standard of care for esophageal cancer has been surgery; there are several variants of the surgical approach. We will discuss combined modality approaches in part II of this series.

The replication-competent oncolytic herpes simplex mutant virus NV1066 is effective in the treatment of esophageal cancer

BACKGROUND

The oncolytic herpes simplex-1 virus, NV1066, is a replication-competent virus that has been engineered to infect and lyse tumor cells selectively and to carry a transgene for enhanced green fluorescent protein (EGFP). The purpose of this study was to determine viral cytotoxicity in an esophageal cancer cell line and to determine whether EGFP expression could be used as a marker of viral infection.

METHODS

BE3 esophageal adenocarcinoma cells were infected with NV1066 in vitro to determine cell kill and viral replication. EGFP expression was assessed by flow cytometry. The in vivo anti-tumor activity of NV1066 was tested in subcutaneous and intraperitoneal xenograft models. EGFP expression was localized in vivo by fluorescent microscopy and fluorescent laparoscopy.

RESULTS

NV1066 effectively replicated within and killed BE3 cells in vitro and in vivo. EGFP expression identified infected tumor cells. After NV1066 treatment in vivo, EGFP expression localized to the tumor. In an intraperitoneal tumor model, EGFP could be visualized endoscopically using a laparoscope with a fluorescent filter.

CONCLUSIONS

NV1066 has oncolytic activity against the BE3 cell line and may be a useful therapy against esophageal cancer. EGFP expression localizes the virus and may help to identify tumor deposits in vivo. Oncolytic activity with NV1066 against gastrointestinal cancers may potentially be tracked by endoscopy.

Preoperative TN staging of esophageal cancer: Comparison of miniprobe ultrasonography, spiral CT and MRI

AIM: To evaluate the value of miniprobe sonography (MPS), spiral CT and MR imaging (MRI) in the tumor and regional lymph node staging of esophageal cancer.

METHODS: Eight-six patients (56 men and 30 women; age range of 39-73 years, mean 62 years) with esophageal carcinoma were staged preoperatively with imaging modalities. Of them, 81 (94%) had squamous cell carcinoma, 4 (5%) adenocarcinoma, and 1 (1%) adenoacanthoma. Eleven patients (12%) had malignancy of the upper one third, 41 (48%) of the mid-esophagus and 34 (40%) of the distal one third. Forty-one were examined by spiral CT in whom 13 were co-examined by MPS, and forty-five by MRI in whom 18 were also co-examined by MPS. These imaging results were compared with the findings of the histopathologic examination for resected specimens.

RESULTS: In staging the depth of tumor growth, MPS was significantly more accurate (84%) than spiral CT and MRI (68% and 60%, respectively, P < 0.05). The specificity and sensitivity were 82% and 85% for MPS; 60% and 69% for spiral CT; and 40% and 63% for MRI, respectively. In staging regional lymph nodes, spiral CT was more accurate (78%) than MPS and MRI (71% and 64%, respectively), but the difference was not statistically significant. The specificity and sensitivity were 79% and 77% for spiral CT; 75% and 68% for MPS; and 68% and 62% for MRI, respectively.

CONCLUSION: MPS is superior to spiral CT or MRI for T staging, especially in early esophageal cancer. However, the three modalities have the similar accuracy in N staging. Spiral CT or MRI is helpful for the detection of far-distance metastasis in esophageal cancer.