Intensive follow-up may be necessary for endoscopically resected esophageal squamous cell carcinoma invading the muscularis mucosae, at least during the first year

We read with interest the article “Clinical outcome after endoscopic mucosal resection for esophageal squamous cell carcinoma invading the muscularis mucosae - a multicenter retrospective cohort study” by Katada et al. [1]. Endoscopic treatment for large esophageal squamous cell carcinoma has been actively performed especially in Japan after the introduction of the endoscopic submucosal dissection (ESD) technique [2]. Among these lesions, those that invade the muscularis mucosa (m3 lesions) are also included to some extent. Katada et al. report that the incidence of lymph node metastasis after endoscopic mucosal resection (EMR) for m3 lesions was only 1.9 % in their retrospective multicenter study. Although the targets of ESD may be slightly different from those of EMR, the extremely low rate and the fact that patients with m3 lesions who did not receive additional treatment did not develop lymph node metastasis encourage us to perform ESD for m3 lesions. Furthermore, according to a report from the 46th Congress of the Japanese Research Society for Esophageal Cancer and Chromoendoscopy, the incidence of lymph node metastasis becomes 4.3 % in low-risk lesions, including those that are less than 50 mm in size, are without vessel permeation, and are not poorly differentiated squamous cell carcinoma, in comparison with a 9.3 % overall incidence of lymph node metastasis in m3 lesions [3]. However, recently, we had experience of a case of an m3 lesion 2.2 cm in size, without vessel permeation, which developed metastases in the abdominal lymph nodes and the liver at 9 months after ESD ([Fig. 1]). The patient had a recurrent carcinoma at the inoperable stage and chemotherapy was the only choice of treatment. Katada et al. state that two patients developed lymph node metastasis at 21 and 48 months after EMR, and that repeated follow-up examinations by means of iodine chromoendoscopy and CT at least every 6 months after EMR may work appropriately, but, in view of our case, we recommend CT with abdominal ultrasonography at least every 3 months during the 1st year after ESD for follow-up of m3 lesions - although there is no answer as to whether this intensive follow-up can rescue a rare case of metastatic disease. In addition, the decision of whether to follow or to give additional treatment should be carefully taken with the consenting patient fully informed about the possibility of inoperable recurrence.

Fig. 1 Esophageal squamous cell carcinoma invading the muscularis mucosa, which recurs as metastases in the abdominal lymph node and the liver. a Endoscopic view reveals a slightly depressed lesion with a hardness that suggests invasive carcinoma. b The m3 lesion is resected with a large specimen, 9.3 × 6.5 cm in size, which contains surrounding intraepithelial high-grade neoplasias. c Histopathology reveals an m3 lesion 2.2 cm in size, without vessel permeation, which compresses the muscularis mucosa deeply with the expanding tumor growth. d CT showing metastases in the abdominal lymph nodes taken at 9 months after endoscopic submucosal dissection.

Competing interests: None

References

• 1 Katada C, Muto M, Momma K. et al . Clinical outcome after endoscopic mucosal resection for esophageal squamous cell carcinoma invading the muscularis mucosae - a multicenter retrospective cohort study.  Endoscopy. 2007;  39 779-783
• 2 Fujishiro M, Yahagi N, Kakushima N. et al . Endoscopic submucosal dissection of esophageal squamous cell neoplasms.  Clin Gastroenterol Hepatol. 2006;  4 688-694
• 3 Oyama T, Miyata Y, Shimatani S. et al . Lymph nodal metastasis of m3, sm1 esophageal cancer [in Japanese with English abstract].  I To Cho. 2002;  37 71-74