Complete resection of the tumor and its entire lymphatic drainage is recommended for long term survival in patients with adenocarcinoma of the esophagogastric junction, provided the tumor can be removed completely. Multivariate analysis identified a complete microscopic and macroscopic tumor resection (R0 resection ) as the single most important prognostic factor.
The surgical strategy is based on topographic location and the preoperatively determined stage.
Among patients with AEG type 1, there is not a significant difference in long-term survival between transthoracic and radical transmediastinal esophagectomy.
Among patients with AEG type 2 tumors, esophagectomy offers no survival benefit over extended gastrectomy, provided a complete tumor resection can be achieved, but esophagectomy is associated with a significantly higher morbidity rate.
In most patients with AEG type 3 tumors, complete tumor removal could be achieved by total gastrectomy with transhiatal resection of the distal esophagus.
Among patients with high-grade dysplasia or early-stage esophagogastric junction tumors of the uT1N0 category on preoperative staging, limited resection of the esophagogastric junction with interposition of an isoperistaltic pedicled jejunal segment results in a complete tumor removal without recurrences on follow-up.
Based on uncontrolled trials, the extended lymphadenectomy in the lower posterior mediastinum and along the celiac axis and the superior border of the pancreas may improve the prognosis of the subgroup of patients who have a limited number of positive lymph nodes.
Lymph node metastases are virtually never present in patients with tumours limited to the mucosa (pT1) and are uncommon in patients with tumours limited to the submucosa (pT1b). This is confirmed when immunohistochemical techniques are used to search for micrometastases in the lymph nodes of such patients.
The decreasing order of lymph node metastases in patients with more advanced tumors is the paracardial region, the posterior lower mediastinum, the lesser and greater curvature side of the stomach, along the left gastric artery toward the celiac axis, at the superior border of the pancreas along the splenic artery toward the splenic hilum, and in the area of the left adrenal gland and the left renal vein.
Therefore an extended lymph node dissection in patients with AEG should include the removal of lymph nodes along the splenic artery, at the splenic hilus, and along the the left renal vein. The potential benefits of a more extensive lymph node dissection achieved with splenectomy may be nullified by the associated morbidity. Splenectomy is justified only for patients with frank lymph node metastases or infiltration of the splenic hilum.
In fact postoperative complications independently influence long term survival.
To conclude, it is recommended a tailored therapeutic treatment to AEG and extensive preoperative staging is a prerequisite for such a tailored strategy.
For patients with tumours staged as uT1 on preoperative endosonography and no evidence of lymph node metastases, a limited resection of the proximal stomach, cardia, and distal esophagus with interposition of a pedicled jejunal segment allows for complete tumor resection and adequate lymphadenectomy with excellent functional results particularly when the vagus nerve can be preserved during the resection( with regard to swallowing function and gastroesophageal reflux) .
An even more limited approach to early tumours of the esophagogastric junction is offered by endoscopic or transgastric mucosal resection, that are recommended in patients limited to the mucosa, because a lymphadenectomy is not possible. However the current preoperative staging modalities are inaccurate to differentiate mucosal from submucosal tumours.
For patients with more advanced but potentially resectable tumours, a complete removal of the primary tumour and its lymphatic drainage usually can be achieved by a radical transmediastinal esophagectomy for patients with AEG type 1 tumours or a total gastrectomy with transhiatal resection of the distal esophagus and en bloc removal of the lymphatic drainage in the lower posterior mediastinum, along the celiac axis and the superior border of the pancreas for patients with AEG type 2 or 3 tumours.
If the likelihood of complete tumor removal by primary tumor resection seems questionable on preoperative staging, these patients with locally advanced tumours are included in multimodal treatment trials with neoadjuvant polichemotherapy or combined radiochemotherapy.
In the staging work up it is essential to rule out peritoneal tumour spread and liver metastases with a diagnostic laparoscopy with laparoscopic sonography
( 1,
2,
3 ).
Fein et al agree that the new classification method for cancer of the cardia is applicable in clinical routine and facilitates the standardization of surgical treatment.
But further investigation is necessary to identify the pathogenesis and rational treatment of type II cancer. In fact there is no consensus on the extent of resection for type II cancer.
Most surgeons are in favour of distal esophageal resection and total gastrectomy.
Others routinely perform distal esophagectomy resection and proximal gastrectomy.
And others perform an esophagogastrectomy, the most radical approach with the highest mortality and morbidity, that in general does not improve survival.
Patients with early stages seem to benefit from total gastrectomy, whereas for the advanced stage prognosis is poor regardless of the extent of gastric resection. Esophagogastrectomy was only done when required by the tumor spread
( 4 ).
References
1) HJ Stein MD, A Sendler MD, U Fink MD and JR Siewert MD. Multidisciplinary approach to esophageal and gastric cancer. Surgical Clinics of North America. Volume 80, number 2, April 2000.
2) JR Siewert MD, HJ Stein MD, and U Fink MD. Surgical resection for cancer of the cardia. Seminars in Surgical Oncology 1999; 17: 125-131.
3) HJ Stein, M Feith, JR Siewert. Cancer of the esophagogastric
junction. Surgical Oncology 9 (2000) 35-41.
4) M Fein et al. Application of the new classification for cancer of the cardia. Surgery 1998; 124: 707-14.
5) J Stein MD, M Feith MD, J Mueller MD, M Werner MD and JR
Siewert. Limited resection for early adenocarcinoma in Barrett's
Esophagus. Annals of Surgery, 232, 6, 733-742, 2000.
6) Wayman et al. Transhiatal approach to total gastrectomy for adenocarcinoma of the gastric cardia. British Journal of Surgery 1999, 86,
536-540.
7) LE Harrison MD, MS Karpeh MD, and Murray F Brennan MD. Total gastrectomy is not necessary for proximal gastric cancer. Surgery 1998; 123: 127-30.
