A Submucosal Tumor-Like Recurrence of Early Esophageal Cancer after Endoscopic Submucosal Dissection
A 68-year-old man presented with dysphagia of 1-month duration. Three years previously, he had been diagnosed with EEC of the lower esophagus judged to be T1aN0M0 (stage I) and had undergone ESD (). Upon pathological examination, a 1.4×1.1 cm well-to-moderately differentiated squamous cell carcinoma (SCC) was found to have invaded the muscularis mucosa (MM) without penetration (). The vertical resection margin was negative for carcinoma, but the distal resection margin was positive for SCC and this ESD was regarded as an incomplete resection. However, on follow-up endoscopy (at 4th day after ESD), the endoscopic findings suggesting remnant cancer was not seen and argon plasma coagulation (APC) was performed for the distal margin. Thereafter, we checked the existence of residual carcinoma by serial follow-up studies, including chest computed tomography (CT) scans and endoscopy with biopsy over the course of 18 months (). We identified no recurrence on the esophagus. The patient was then lost to follow-up.\nOn the current visit, the patient reported that he was a current smoker with a 20 pack-year smoking history. Laboratory findings were unremarkable. On the endoscopic images, the post-ESD scar was observed at the lower esophagus, but it looked like an SMT (). At its center, a tiny nodular change was seen, and this was unstained by lugol chromoendoscopy (). On magnified endoscopy with narrow band imaging, an irregular microvascular pattern was observed in the nodular area (). Endoscopic biopsy revealed recurrent SCC. On endoscopic ultrasonography (EUS), the cancer was found to have invaded the muscularis propria, but there was no LN enlargement (). Chest CT scans showed a 1.5 cm low density mass at the lower esophagus, and positron emission tomography showed increased 18fluoro-2-deoxyglucose uptake in the same area. Ivor-Lewis esophagectomy with 2-field LN dissection was performed. On gross examination, the esophagus was found to have a relatively ill-defined white solid mass, 1.5×1.5 cm in size, located mainly on the submucosa and muscularis propria in cross section (). On pathological examination, the SCC was found to have invaded the adventitia with a mixed infiltrative and expanding growth pattern (). There was no evidence of LN metastasis. The patient subsequently underwent six cycles of adjuvant chemotherapy (5-fluorouracil plus cisplatin). He is currently alive, and there has been no recurrence throughout the 17-month follow-up period.