Risk factors of lymph node metastasis in T1 esophageal squamous cell carcinoma

Background and Aim: To perform endoscopic mucosal resection (EMR) for T1 esophageal cancer, it is essential to estimate the lymph node status exactly. In order to evaluate the feasibility of EMR for esophageal cancers, we evaluated the clinicopathological features of T1 esophageal squamous carcinomas with an emphasis on the risk factors and distribution patterns of lymph node metastasis. Methods: From 1994 to 2006, a total of 200 patients with T1 esophageal carcinoma were treated surgically in our institution. Among them, clinicopathological features were evaluated for 197 consecutive patients with T1 squamous cell carcinoma. Results: The frequency of lymph node involvement was 6.25% (4/64) in mucosal cancers and 29.3% (39/133) in submucosal cancers (P < 0.001). In patients with M1 (n = 32) and M2 (n = 14) cancers, no lymph node metastasis was found. In multivariate analysis, size larger than 20 mm, endoscopically non‐flat type, and endo‐lymphatic invasion were significant independent risk factors for lymph node metastasis. The differentiation of tumor cell was not a risk factor for lymph node metastasis. Conclusions: We suggest that EMR may be attempted for flat superficial squamous esophageal cancers smaller than 20 mm. After EMR, careful histological examination is mandatory.     

The use of minimally invasive surgery for lymph node recurrence after endoscopic mucosal resection of superficial esophageal cancer

A 73-year-old man was diagnosed with superficial esophageal cancer, and endoscopic mucosal resection was performed. Histologically, the lesion was found to be a squamous cell carcinoma invading the muscularis mucosae without vascular invasion. The patient was followed without being given adjuvant therapy, and lymph node recurrence along the lesser curvature of the stomach was found after 2.5 years. He underwent laparoscopic removal of the metastatic lymph node and cholecystectomy for cholecystolithiasis. He had two courses of adjuvant chemotherapy and showed no recurrence during 3 years of observation. Although the effectiveness of surgical resection for nodal recurrence of esophageal cancer remains controversial, this case highlights the possibility of salvage resection using minimally invasive surgery.     

Effectiveness of endoscopic mucosal resection with submucosal saline injection technique for superficial squamous carcinomas of the esophagus

BACKGROUND: Intraepithelial cancers (m1 cancer) and cancers that penetrate the basement membrane but do not approach the muscularis mucosae (m2 cancer) do not have lymph node metastasis and thus can be removed completely with mucosal resection. Therefore, in this study, the effectiveness of endoscopic mucosal resection with submucosal saline injection for removal of superficial esophageal cancers was investigated prospectively. METHODS: Twenty-five superficial esophageal cancers in 21 patients were removed with submucosal saline injection. When it was thought that a tumor had not been completely resected en bloc, it was removed completely in piecemeal fashion. Endoscopy was repeated 1, 3, 6, 12 months or more after endoscopic resection. RESULTS: All superficial esophageal cancers were completely removed: 18 (72%) en bloc and 7 (28%) by piecemeal resection. No recurrence was found during a mean observation period of 2.0 years (range 0.8 to 3.6) after resection. Bleeding occurred in 5 cases (24%) during or after resection but was successfully treated with the endoscopic alginate or thrombin spray technique. There was no perforation. CONCLUSION: Endoscopic mucosal resection with submucosal saline injection is effective for removal of superficial cancers of the esophagus.     

Endoscopic mucosal resection for early adenocarcinoma arising in Barrett's esophagus

A 58‐year‐old man was diagnosed to have an esophageal adenocarcinoma arising in Barrett's esophagus by screening examination at the previous hospital. Endoscopically, a slightly reddish elevated lesion with a central depressed component was detected in the Barrett's epithelium. Endoscopic ultrasonography showed the thickness of the second layer of the esophagus and no enlarged lymph node. Histological examination of a biopsy specimen revealed well or moderately differentiated adenocarcinoma. From these findings, the lesion was diagnosed as a mucosal esophageal cancer, type IIa + IIc, arising in Barrett's esophagus. As he refused operation, the lesion was resected endoscopically with his informed consent. Histologically, the resected specimens showed moderately differentiated adenocarcinoma arising in Barrett's esophagus. The adenocarcinoma had invaded the superficial muscularis mucosa, but was limited to the deep one with no vessel invasion. Barrett's esophagus often has a double muscularis mucosa. Connective tissues containing vascular and lymphatic vessels exist between them. However, one consideration is whether the existence of vessels between the double muscularis mucosa and the presence of vessel invasion are risk factors for metastasis. In order for a definitive indication for endoscopic mucosal resection, the frequency of lymph node and distant metastasis in cases of early Barrett's cancer needs to be investigated.     

Long-term outcome after endoscopic mucosal resection in patients with esophageal squamous cell carcinoma invading the muscularis mucosae or deeper

BACKGROUND: Endoscopic mucosal resection is recommended for squamous cell carcinoma of the esophagus confined to the lamina propria. However, endoscopic mucosal resection is often performed in patients with tumors that invade the muscularis mucosa or upper submucosa to minimize surgical invasiveness, despite the increased risk of lymph node metastasis. This study prospectively evaluated long-term outcome in such patients. METHODS: Twenty-six consecutive patients with squamous cell esophageal carcinoma invading the muscularis mucosa or submucosa who underwent endoscopic mucosal resection from June 1992 through March 2000 (extended endoscopic mucosal resection group) were studied. As control group, 44 consecutive patients with esophageal carcinoma invading the muscularis mucosae or upper third of the submucosa and no preoperative evidence of lymph node metastasis who underwent esophagectomy during the same period (surgical resection group) were studied. RESULTS: Overall survival rates at 5 years in the extended endoscopic mucosal resection group and surgical resection group were, respectively, 77.4% and 84.5%. There was no significant difference between survival distributions. Cause-specific survival rates at 5 years in extended endoscopic mucosal resection and surgical resection groups were, respectively, 95.0% and 93.5%. Survival curves for the groups were similar. CONCLUSION: Although patients were not randomized to extended endoscopic mucosal resection or surgical resection in this study, the results suggest that endoscopic mucosal resection may be safe and effective for management of squamous cell esophageal carcinoma invading the muscularis mucosae or upper submucosa.     

Individualization of lymphadenectomy in superficial esophageal squamous cell cancer

Background As the result of the development of imaging means, the incidence of discovery of superficial esophageal squamous cell cancer (ESCC) has recently increased. Various treatment methods such as endoscopic mucosal resection and reduction of lymphadenectomy have been performed to preserve the quality of life. Because lymph node metastasis occurs even in the early stage of esophageal cancer, we should carefully select the treatment method, including lymphadenectomy. Methods We analyzed the distribution of solitary lymph metastasis of 27 superficial esophageal cancers. To analyze the distribution of micrometastasis, a total of 1542 lymph nodes obtained from 46 patients with pN0 submucosal cancer were immunohistochemically examined by cytokeratin antibody. Sentinel node mapping was performed in 23 patients with clinical T1 tumors. Results The location of lymph node metastasis in the 22 patients with solitary lymph metastasis in superficial cancer was limited to recurrent nerve nodes in the upper thoracic esophagus, recurrent nerve nodes, paraesophageal nodes, or perigastric nodes in the middle or lower thoracic esophagus. For eight patients with lymph node micrometastasis in pN0 patients with superficial esophageal cancer, the locations of micrometastasis were similar to those of solitary metastasis. In sentinel node mapping, all nodal metastasis was included in sentinel nodes with a single exception. Conclusions Individual lymphadenectomy in superficial ESCC will be established using methods such as analysis of past data, clinical diagnosis of lymph node metastasis by imaging, and sentinel node navigation surgery, including the diagnosis of micrometastasis.     

Tumor cell dissociation score highly correlates with lymph node metastasis in superficial esophageal carcinoma

BACKGROUND: It is still not clear which parameters are important for predicting the metastatic potential of superficial esophageal squamous cell carcinoma (SESCC). The purpose of the present paper was thus to investigate tumor cell dissociation (TCD) in SESCC as a predictive factor of lymph node metastasis. METHODS: Thirty-three SESCC were classified into four groups based on the depth of tumor invasion. Carcinomas not invading as far as the muscularis mucosa were classified as group A; carcinomas invading to the muscularis mucosa or less than one-third of the upper submucosa were classified as group B; those invading to the middle layer of the submucosa were classified as group C; and those invading one-third of the lower submucosa were classified as group D. The TCD score was calculated by dividing the length of the TCD region by the maximal longitudinal length of the area of invasion into or beyond the lamina propria, and multiplying by 100. E-cadherin expression of the carcinomas was investigated in the TCD area and the successive area of mucosal invasive carcinoma (SAM). RESULTS: The incidence of lymph node metastasis was 0% in group A, 10% in group B, 36.4% in group C and 57.1% in group D. The mean TCD scores (+/-SEM) of SESCC with lymph node metastasis were higher than that without (85.3 +/- 5.7, 16.3 +/- 3.9, respectively; P < 0.001). In group C, the TCD score of cases with lymph node metastases was higher than in those without lymph node metastasis (P < 0.001). E-cadherin expression was significantly reduced in the area of TCD compared with the SAM located over the TCD area (P < 0.001). CONCLUSIONS: The TCD score is an important predictive marker for lymph node metastasis in SESCC. Clinical evaluation of TCD scores in endoscopic mucosal resection (EMR) specimens would enable accurate prediction of lymph node metastasis and extend the indication of EMR treatment for SESCC.     

Primary minute invasive de novo colonic adenocarcinoma appearing as submucosal tumor

A 4 mm white-yellow submucosal tumor-like lesion was detected in the sigmoid colon of an asymptomatic 52-yr-old Japanese man. Because the lesion was unexpectedly suspicious for adenocarcinoma by pathological examination of the biopsy specimen, it was treated by endoscopic mucosal resection. The specimen obtained demonstrated well-differentiated adenocarcinoma without any adenomatous element, and was located principally in the submucosal layer with a maximum depth of 1600 mum from the muscularis mucosae. The cancer exposed to the luminal surface was pathologically concluded to be diminutive. Intriguingly, aggregation of lymphocytes was found beneath the mucosal layer, which might have compromised the integrity of the muscularis mucosae. Because of deep submucosal infiltration and the latent aggressive nature of de novo cancer, the patient underwent an additional partial sigmoidcolectomy, which demonstrated no residual cancer and no regional lymph node metastasis. The lesion in this patient exhibited a previously undescribed appearance of de novo colon cancer as submucosal tumor in an early phase of growth.     

Can common hepatic artery lymph node dissection be safely omitted in surgery for clinical T1N0 thoracic esophageal squamous cell carcinoma?

Common hepatic artery lymph node dissection is regarded as a standard procedure in esophageal cancer surgery because of aggressive lymphatic dissemination of esophageal cancer. However, lymph node dissection can prolong operation time and may be associated with complications such as chylous ascites. Here, we aimed to evaluate the effectiveness of common hepatic artery lymph node dissection in clinical T1N0 thoracic esophageal squamous cell carcinoma. Between 1996 and 2009, 1390 patients underwent surgery for esophageal cancer in our institution, and 209 were found to have clinical T1N0 disease. Exclusion criteria were nonsquamous carcinoma, double primary cancer, definite distant metastasis, administration of neoadjuvant treatment, and incomplete abdominal lymph node dissection. We retrospectively analyzed medical records, operative and pathologic data, and follow‐up information. Forty‐two patients were excluded from the study. Among the 167 enrolled patients, preoperative endoscopic ultrasound evaluation was performed in 160 patients. Fifty‐two patients had distal esophageal or esophagogastric junction tumor. Surgery included 2 cases of tri‐incisional esophagectomy, 17 cases of transhiatal esophagectomy, and 148 cases of two‐field esophagectomy (Ivor Lewis operation). Common hepatic artery lymph node dissection was performed in all cases, and none of the patients had metastasis. Mean follow‐up period was 35.4 ± 28.7 months. In‐hospital mortality was one, and 5‐year survival rate was 80.6%. Among the 15 patients with recurrence, there were two distant metastases and five distant and local recurrences but no intra‐abdominal recurrence with common hepatic artery lymph node. Common hepatic artery lymph node dissection may be safely omitted in surgery for clinical T1N0 esophageal squamous cell carcinoma when preoperative evaluations including chest computed tomography, positron emission tomography and computed tomography, and esophagogastroduodenoscopy or endoscopic ultrasound are performed.     

Recurrence after endoscopic mucosal resection of esophageal squamous cell carcinoma invading the muscularis mucosae or upper submucosa

Background: Endoscopic mucosal resection (EMR) is recommended for cases of squamous cell carcinoma of the esophagus in which the tumor is confined to the lamina propria mucosa. However, EMR is often performed in patients whose tumors invade the muscularis mucosae (m3) or upper submucosa (sm1) to minimize surgical invasion, despite the increased risk of lymph node metastasis. We evaluated patients who were found to have distant or lymph node metastasis after EMR for such lesions. Methods: Thirty‐four consecutive patients with esophageal carcinoma invading m3 or sm1 who underwent EMR during the period from June 1992 through March 2001 (extended EMR group) were studied. Results: Five of these patients were found to have distant or lymph node metastasis on follow up. Patient 1 died of lung metastasis 34 months after EMR. Patient 2 underwent chemotherapy because of an abnormally high value of squamous cell carcinoma (SCC) antigen. Patient 3 died of upper mediastinal lymph node metastasis 62 months after EMR. Patient 4 underwent total gastrectomy because of gastric wall metastasis 41 months after EMR and underwent chemoradiotherapy because of upper mediastinal lymph node metastasis 87 months after EMR. Patient 5 was found to have cardiac lymph node metastasis by follow‐up endoscopic ultrasonography examination 42 months after EMR and underwent curative lymph node dissection. Conclusion: It is unlikely that patient 1 and patient 2, both with probable distant metastasis, received inadequate treatment. Surgery with lymph node dissection usually cannot prevent distant metastasis. The patients with lymph node recurrence (patient 3 and patient 4) should have been followed up more carefully. We believe that patients with early lymph node metastasis, such as patient 5 in this study, should undergo curative surgical resection. Patients undergoing extended EMR should be carefully followed up for a long period to enable early detection and treatment of lymph node metastasis.     

Value of subcarinal lymph node dissection in esophageal cancer surgery: A case-control study

We investigated the value of subcarinal lymph node dissection in esophageal cancer surgery. Altogether, 240 patients with esophageal cancer admitted to our department between June 2012 and January 2016 were prospectively assigned to an experimental group (subcarinal lymph node dissection group, n = 120 cases) and a control group (uncleaned group, n = 120 cases). The number of subcarinal lymph nodes and the rate of subcarinal lymph node metastasis were determined, and the factors influencing subcarinal lymph node metastasis were analyzed using logistic regression in the experimental group. The operation time, postoperative complications, intraoperative blood loss, postoperative hospital stay, total postoperative hospital cost, and 5-year survival rate were compared between the 2 groups. In the experimental group, an average of 6.03 subcarinal lymph nodes were dissected, and the lymph node metastasis rate was 18.33%. The subcarinal lymph node metastasis rate in the experimental group was related to the size of the subcarinal lymph nodes, depth of tumor invasion, and tumor location. The 5-year survival rate was higher in the experimental group than in the control group (44.2% vs 30.0%, χ² = 6.407, P = .04). The subcarinal lymph node metastasis rate in patients with esophageal cancer is high. Patients with mid-thoracic esophageal cancers that infiltrate beyond the esophageal muscle layer with subcarinal lymph node size > 1.0 cm should undergo lymph node resection, despite increased operation time, incidence of postoperative pulmonary infection, hospitalization time, and total postoperative cost; lymph node resection may improve the 5-year survival rate.     

Lymph node dissection with cervical approach as a salvage surgery for locoregional failure after definitive chemoradiotherapy in a patient with recurrent esophageal carcinoma: report of a case

Salvage surgery is one important therapeutic option after locoregional failure of definitive chemoradiotherapy (dCRT) in patients with advanced or recurrent esophageal carcinoma. We have performed cervical lymph node dissection as a salvage surgery after chemoradiotherapy in a patient with recurrent esophageal carcinoma. A 54-year-old Japanese man was admitted to our hospital because of multiple lymph node metastases after endoscopic submucosal dissection (ESD) for early-stage esophageal carcinoma. The patient underwent a circumferential ESD of early-stage esophageal carcinoma in another hospital. The esophageal carcinoma, measuring 75 × 60 mm in size, was a superficial spreading type located in the middle portion of the thoracic esophagus. Histology of the resected specimen revealed a moderately to poorly differentiated squamous cell carcinoma, and the depth of invasion was limited within the mucosal layer associated with a small area being attached to the muscularis mucosae. Five months after ESD, lymph node metastases in the regions of right recurrent nerve and the left tracheobronchus were found, for which dCRT was performed. These metastatic lymph nodes disappeared in the chest CT scan images. Lymph node metastasis in the region of the right recurrent nerve then reappeared 8 months after the completion of CRT. Considering the solitary lymph node metastasis and surgical invasiveness, lymph node dissection using a cervical approach was selected as a salvage surgery. Cervical approach for the lymph node dissection in the region of right recurrent nerve may be one feasible option as a minimally invasive salvage surgery for patients with recurrent esophageal carcinoma after dCRT.     

Location of Early Colorectal Cancers at Fold-Top May Reduce the Risk of Lymph Node Metastasis

Purpose This study was designed to look for significant correlations between location of early colorectal cancer, distance from muscularis mucosae to muscularis propria, and the frequency of lymph node metastasis. Methods A total of 166 early colorectal cancers, including 67 surgically resected lesions, were evaluated. The cancers were divided into two groups: metastatic and nonmetastatic. Cancer lesions were further subtyped at the fold-top or fold-bottom. Macroscopic classifications and histology were performed. Absolute invasive depth and distance from muscularis mucosae to muscularis propria was measured. Multivariate analysis was used to assess relationships among the variables. Results The percentage of polypoid cancer lesions at fold-bottom was higher than at fold-top (74.5 vs. 51.8 percent), whereas flat-type cancer lesions at fold-bottom occurred less often than at fold-top (8.2 vs. 30.4 percent). Logistic regression showed that deep absolute invasive depth, lymphatic and vessel invasion, and cancer location (at fold-bottom) were the significant risk factors for early colorectal cancers leading to lymph-node metastasis. The distance from muscularis mucosae to muscularis propria with lymph-node metastasis (1,396.7 ± 728.4 μm) was shorter than without lymph-node metastasis (3,533.9 ± 2,507.8 μm; P < 0.01). Multivariate analysis showed that distance from muscularis mucosae to muscularis propria was a statistically significant factor for early colorectal cancers leading to lymph node metastasis (P = 0.0054). Conclusions We conclude that early colorectal cancers at the fold-top or with a long distance from muscularis mucosae to muscularis propria have less tendency to metastasize to lymph nodes. Clinically, these results provide evidence of a new indicator of endoscopic mucosal resection for early colorectal cancers at the fold-top.     

Diagnostic accuracy of tumor staging and treatment outcomes in patients with superficial esophageal cancer

Background We examined the current status and diagnostic accuracy of currently available techniques for tumor staging and assessed treatment outcomes in patients with superficial esophageal cancer who received esophaguspreserving therapy, such as endoscopic mucosal resection (EMR) alone or combined with chemoradiotherapy (CRT). Methods In 274 patients with superficial esophageal cancer, we examined the depth of tumor invasion and the degree of lymph node metastasis by means of endoscopy, magnifying endoscopy, endoscopic ultrasonography (EUS), computed tomography (CT), and cervical and abdominal ultrasonography (US). We compared treatment outcomes among treatment groups according to the depth of tumor invasion. Results The rates of correctly diagnosing the depth of tumor invasion were 89.6% on conventional endoscopy, 90.1% on magnifying endoscopy, and 85% on scanning with a high-frequency miniature ultrasonic probe (miniature US probe). Diagnostic accuracy for the m3 or sm1 cancers was poor. Magnifying endoscopy allowed invasion to be more precisely estimated, thereby improving diagnostic accuracy. However, lesions that maintained their surface structure despite deep invasion were misdiagnosed on magnifying endoscopy. A miniature US probe was useful for the assessment of such lesions. The diagnostic accuracy of EUS for lymph node metastasis was 83%, with a sensitivity of 76%. The sensitivity of CT was 29%, and that of cervical and abdominal US was 17%. Patients with m1 or m2 cancer had good outcomes after esophagus-preserving therapy. Although there were no significant differences in survival rates, many patients with sm2 or sm3 cancer who received CRT died of their disease. Nodal recurrence was diagnosed by EUS. In patients who received CRT, the time to the detection of recurrence was slightly prolonged. Conclusions Long-term follow-up at regular intervals is essential in patients with m3 or sm esophageal cancers who receive esophagus-preserving treatment. At present, EUS is the most reliable technique for the diagnosis of lymph node metastasis and is therefore essential for pretreatment evaluation as well as for follow-up. Earlier detection of recurrence at a level that would potentially salvage treatment remains a topic for future research. Review articles on this topic also appeared in the previous issue (Volume 4 Number 3). An editorial related to this article is available at .     

食管早期癌和癌前病变超声内镜诊断及内镜下食管黏膜切除术的临床研究

目的探讨食管早期癌和癌前病变超声内镜诊断价值及内镜下食管黏膜切除术的临床治疗价值。方法 61例食管早期癌和癌前病变行超声内镜检查探测病变浸润深度,位于黏膜层及黏膜肌层的食管早期癌和癌前病变行内镜下食管黏膜切除术（EMR）,位于黏膜下层的食管早期癌行外科手术治疗。EMR术28例,外科手术33例。比较超声内镜和术后病理判断病变浸润深度。结果超声内镜判断食管黏膜内癌的特异性和敏感性为94.1%（48/51）、98.0%（48/49）;黏膜下癌的特异性和敏感性为80.0%（8/10）、72.7%（8/11）;鉴别黏膜内癌及黏膜下癌浸润深度准确率为91.8%（56/61）。28例EMR术后病理：14例食管早期癌和12例食管黏膜中重度异型增生完全切除,完全切除成功率为92.9%（26/28）,观察3～45个月无复发。结论超声内镜能较准确鉴别食管早期癌和癌前病变浸润深度,黏膜切除术治疗食管早期癌和癌前病变是安全有效的内镜治疗方法。     

Magnifying endoscopic observation of superficial esophageal carcinoma

The depth of tumor invasion of esophageal cancers is one of the most important indicators for predicting lymph node metastasis, so much effort has been directed toward improving the diagnosis of tumor invasion, especially in cases of super?cial esophageal cancer. Ultra‐high magnifying endoscopic observation for esophageal cancer was performed using an Olympus Q240Z, which has a 100 × magnifying capacity. We succeeded in observing looped capillary vessels inside the papillae (intrapapillary capillary loop: IPCL). The IPCL inside an m1 cancer showed abnormal changes such as ‘dilation, weaving, changes in caliber, variety of shapes’. Furthermore, we found that super?cial esophageal cancers show characteristic changes according to the depth of invasion. In our investigation, the rate of accurate diagnosis using magnifying endoscopy for super?cial esophageal cancers was 83.1% in cases for which ?ne pictures were obtained. Observations of the microvascular architecture of super?cial esophageal carcinoma using magnifying endoscopy are useful for diagnosing the depth of tumor invasion, especially for super?cial cancers with invasion reaching to the muscularis mucosae (m3) and slightly into the submucosa (sm1) esophageal cancer.     

INDICATIONS FOR ENDOSCOPIC MUCOSAL RESECTION FOR EARLY COLORECTAL CANCER: SHOULD THEY BE STRICT OR SHOULD THEY BE EXPANDED?

Endoscopic technologies have been developed greatly. As for early gastric cancer, the indications for endoscopic mucosal resection for early colorectal cancer have been widened recently. Technological advances can support wider and deeper resections using endoscopy but the remaining problem for the endoscopic management of cancer is lymph node metastasis. I discuss here the indication for endoscopic mucosal resection for early colorectal cancer to bring into focus the risk factors for metastasis to lymph nodes.     

Predictive factors for lymph node metastasis in esophageal squamous cell carcinomas contacting or penetrating the muscularis mucosae: the utility of droplet infiltration

Background Tissue features to predict the presence or absence of lymph node metastasis (pN) in cases of esophageal squamous cell carcinoma found to contact or penetrate the muscularis mucosae (m3) on endoscopic mucosal resection (EMR) have yet to be clarified in detail. This study was conducted to determine the utility of droplet infiltration (DI) as a candidate. Methods In 27 m3 esophageal squamous cell carcinoma cases who underwent esophagectomy, DI parameters (longitudinal diameter, DIs; number of constituent cells, DIn; distance from the primary focus, DId) for droplet infiltration were examined to allow comparison with vessel permeation (VP) as a predictive factor for lymph node metastasis. Results DIs ≤ 20 μm, DIn ≤ 4, and DId ≥ 200 μm all demonstrated relations with pN (P = 0.001, 0.006, and 0.03, respectively). As predictive factors for lymph node metastasis, DIs ≤ 20 μm and DIn ≤ 4 had sensitivity and likelihood ratios (LR) equal to or higher than VP. Conclusions Tissue features of DI (DIs ≤ 20 μm and DIn ≤ 4) can be applied as predictive factors for lymph node metastasis in m3 esophageal cancers after EMR. This is the English version of a research paper reported in Gastroenterol Endosc 2004;46:2086–94.     

Early esophageal cancer with epidermization diagnosed and treated with endoscopic resection

The patient was a 57-year-old man who had undergone endoscopic submucosal dissection for early esophageal cancer (distance from incisor tooth, 30 cm) when he was 50 years of age. Pathological findings showed squamous cell carcinoma invading the lamina muscularis mucosae and mild lymphatic invasion. Considering the possibility of lymph node metastasis and distant metastasis, we administered radiation chemotherapy (CDDP+ 5-FU, total radiation 41.4 Gy) in the same year. Two years later, follow-up endoscopy revealed a white, flat, elevated lesion in the thoracic esophagus (distance from incisor tooth, 36 cm) that was not stained by Lugol’s iodine. A biopsy of this lesion was performed. Although esophageal epidermization was seen, there were no findings suggestive of malignancy. The lesion grew slightly during four and a half years of follow-up after identification. We performed a repeat biopsy of the lesion, and the tissue was diagnosed as atypical epithelium, so we performed endoscopic mucosal resection for diagnostic and therapeutic purposes. The postoperative pathological diagnosis was squamous cell carcinoma of T1a-LPM with epidermization due to its histological features. To the best of our knowledge, this is the first report of esophageal cancer accompanied by epidermization.     

Clinicopathologic analysis of lymph node metastasis in surgically resected superficial cancer of the thoracic esophagus

We examined lymph node metastasis clinicopathologically in 236 cases of superficial cancer (T1, Tis) of the thoracic esophagus surgically resected at our department without adjuvant treatment. Mucosal cancer was observed in 112 cases (47%) and submucosal cancer in 124 cases (53%). Lymph node metastasis was present in 3% of mucosal cancer cases and 41% of submucosal cancer cases. By the recent pathologic subclassification of the extent of the cancerous invasion in superficial esophageal cancer, mucosal cancer and submucosal cancer were each divided into three subtypes according to the extent of invasion, i.e. m1, m2, m3, sm1, sm2 and sm3 cancers. There was no case of lymph node metastasis in m1 and m2 cases, but it was observed in 8% of m3 cases, in 11% of sm1 cases, in 30% of sm2 cases and in 61% of sm3 cases. The number of involved nodes was three or less in m3 and sm1 cases, however four or more involved nodes were observed in 14% of sm2 cases and in 24% of sm3 cases. Positive lymph nodes were found only in the mediastinum in m3 and sm1 cases. On the contrary, they were found extensively in the mediastinum, the abdomen and the neck and in two or more regions in 27% of sm2 cases and in 38% of sm3 cases. Considering the location of positive nodes, the recurrent nerve lymph nodes were most frequently involved, followed by the cardiac lymph nodes. A similar tendency was observed in cases with single node metastasis. The 5‐year survival rate of cases from m1 to sm1 was similar. That of sm3 cases was significantly worse than that of other groups. Based on the clinical results, the therapeutic guidelines for superficial cancer of the thoracic esophagus are considered to be as follows: (i) in m1 and m2 cancer, endoscopic mucosal resection is generally indicated in principle, although transhiatal esophagectomy may be indicated in some cases; (ii) in m3 and sm1 cancer, endoscopic mucosal resection is performed initially, then subsequent treatment is selected if necessary; (iii) in sm2 and sm3 cancer, conventional transthoracic esophagectomy with systematic lymph node dissection is indicated.