Is there a place for endoscopic mucosectomy in early cancers of the cardia or esophagogastric junction?
T. Kawano, M. Endo (Tokyo)
Recently, the number of early cancers detected in the esophagogastric junction (EGJ) has been increasing with advances in endoscopic examination. Endoscopic mucosectomy (EM) for lesions in the EGJ is relatively difficult because the EGJ is a physiologically constrictive region. We have devised new techniques for mucosectomy with negative pressure (suction) called np-EEM (endoscopic esophageal mucosectomy with negative pressure using a transparent overtube) and EMRC (endoscopic mucosal resection using a cap-fitted panendoscope) for early esophageal cancers [1, 2]. With these techniques, it is not difficult to perform EM in the EGJ and cervical esophagus as well. In this paper, we describe the np-EEM technique and its usefulness for the evaluation of early cancers located at the EGJ and near EGJ.
Endoscopic mucosectomy by the np-EEM method
Instruments and technique
The np-EEM method requires a specially designed overtube called a multi-purpose tube (MP tube, MDU type) (Figure 1). The MP tube is made entirely of almost transparent silicone, 60 cm (type A) or 55 cm (type B) in length, 15.5/12.0 mm in outer/inner diameter, with a proximal balloon for controlling the intraluminal negative pressure, a distal outer balloon for compression, a working channel, and a side hole for some management procedures. At first the MP tube was made manually by us, but it is now commercially available (Create Medic, Tokyo, Japan). Preparation is the same as for usual endoscopy, and an MP tube overlaid on the panendoscope can be inserted after endoscopic observation with little discomfort to the patient because the outer diameter is 15.5 mm and the tube is soft (Figure 2).
Figure 1. MP tube.
Figure 2. The techniques of endoscopic esophageal mucosectomy. From  with permission.
Is there a place for endoscopic mucosectomy in early cancers of the cardia or EGJ ?
Based on our experience with 97 patients with esophageal diseases receiving endoscopic mucosectomy, the method is safe and easy for lesions that are elevated after submucosal saline injection (negative non-lifting sign) and offers detailed histopatholocial findings, i.e. depth of tumor invasion, lymphatic and vessel involvement, and safety margin of resection . We believe that endoscopic mucosectomy has an important diagnostic place in patients with superficial esophageal cancer suspected of being mucosal or superficial submucosal for selecting the most appropriate therapeutic modality. In np-EEM, the MP tube allows reliable, wide (3 x 2 cm in average) mucosectomy at any place in the esophagus. Moreover, repetitive mucosectomy is also easy. Although we have only 6 cases of EM in or near the EGJ (Figures 3 and 4), we believe the application of np-EEM for diseases in the EGJ offers many advantages to patients with small early cancers.
Figure 3. A case of mucosectomy by np-EEM. a, b, c. Endoscopic view of a so-called inflammatory polyp associated with reflux esophagitis on the EGJ (c: through a side hole of the MP tube). d. Artificial ulcer on the EGJ after mucosectomy. e. Macroscopic view of the mucosectomized specimen. SCJ: squamo-columnar junction.
Figure 4. A case of mucosectomy by np-EEM. a, b. Resected specimen of a squamous cell carcinoma located on near EGJ. SCJ: squamo-columnar junction. c. Endoscopic view of the EGJ 3 days after mucosectomy.