What should be the extent of esophageal and gastric resection?
M. Endo (Tokyo)
Cancers at the esophagogastric junction (EGJ) are classified into three types according to the general rules and guidelines widely used in Japan (Figure 1). The surgical problems are how to remove the tumors entirely and to what extent the lymph nodes should be dissected.
We examined 82 cases of adenocarcinoma at the EGJ. Left thoraco-abdomino-phrenotomy at 6th or 7th intercostal space was performed in about a half of these patients. The remaining half of the patients underwent laparotomy and phrenotomy. In the thoracotomy patients phrenotomy was done from the costal arch to the esophageal hiatus. Most adenocarcinomas at the EGJ were beyond the muscle layer. There was no T1 cancer. T2 cancer was found in 38%, T3 cancer in 49% and T4 cancer in 12% of cases.
With regard to the length of the surgical margin and the presence of cancer cells at the proximal edge on the resected specimen, no cancer cell was observed at the proximal edge in cases in which the surgical margin was more than 3 cm in length.
Lymph node metastases were found in 83% of patients. Their incidence in regional perigastric lymph nodes was most frequent, followed by lymph nodes along the left gastric artery (26%) and the splenic artery (18%). On the contrary, the rate of metastases in middle, lower thoracic paraesophageal lymph nodes and lower mediastinal lymph nodes was low (1-4%). Metastases of subcranial lymph nodes and upper mediastinal nodes could not be observed. Thus, lymph node dissection should be performed beneath the bifurcation.
The extent of esophageal invasion and metastatic rate were evaluated in 44 patients who underwent thoracotomy. Metastases in mediastinal lymph nodes were not found in cases with invasion less than 1 cm in length. Paraesophageal lymph nodes were involved in cases in which the esophageal lesion was more than 3 cm in size.
A clinicopathologic evaluation of 39 patients with squamous cell carcinoma at the EGJ was made. Lymph node metastases were observed in 72% of patients, mostly in the upper abdomen and in the whole mediastinum.
The five-year survival rate of adenocarcinoma at the EGJ was 21.8%. By contrast, that of squamous cell carcinoma at the EGJ was 48.8%.
Figure 1. Cancer of the esophagogastric junction. Tumor is located at the lower third of the esophagus and "C" area of the stomach.
1) 82 specimens of adenocarcinoma at the EGJ resected were examined in our department;
2) no cancer cells were observed at the proximal edge of the resected specimen in cases in which the surgical margin was more than 3 cm in length;
3) lymph node metastases were found in 83% of patients, most frequently in paragastric lymph nodes. Metastases were also found in mediastinal lymph nodes. Lymph node dissection should be performed distally from the bifurcation through the abdomen;
4) clinicopathologic comparison of 39 patients with squamous cell carcinoma at the EGJ revealed lymph node metastases in 72% of patients throughout the entire mediastinum.