Unrecognizable intramucosal spread of diffuse-type mucosal gastric carcinomas of less than 20 mm in size

Endoscopic Features of Undifferentiated-Type Early Gastric Cancer in Patients with Helicobacter pylori-Uninfected or -Eradicated Stomachs: A Comprehensive Review

Since the indications for endoscopic submucosal dissection have been expanded to include undifferentiated-type early gastric cancers, improvements in preoperative diagnostic ability have been an area of research. There are also concerns about the impact on the diagnosis of Helicobacter pylori infection. Based on our previous studies, in undifferentiated-type early gastric cancers, magnifying endoscopy with narrow-band imaging is useful for delineating the demarcation regardless of the tumor size. Additionally, inflammatory cell infiltration appears to be a cause of misdiagnosis, suggesting that the resolution of inflammation could contribute to the accurate diagnosis of demarcations. As such, the accuracy of demarcation in eradicated and uninfected cases is higher than that in non-eradicated cases. The common features of the endoscopic findings were discoloration under white-light imaging and a predominance of sites in the lower and middle regions. The uninfected group was characterized by smaller tumor size, flat type, more extended intervening parts in magnifying endoscopy with narrow-band imaging, and pure signet ring cell carcinoma. In contrast, the eradication and non-eradication groups were characterized by larger tumor size, depressed type, and wavy microvessels in magnifying endoscopy with narrow-band imaging. In this comprehensive review, as described above, we discuss the diagnosis of demarcation of undifferentiated-type early gastric cancers, undifferentiated-type early gastric cancers that developed following H. pylori eradication, and H. pylori-uninfected undifferentiated-type early gastric cancers, with a focus on studies with self-examination and endoscopic findings and describe the future direction.

Risk of lymph node metastasis and feasibility of endoscopic submucosal dissection in undifferentiated-type early gastric cancer

BACKGROUND

Whether endoscopic submucosal dissection (ESD) applies to undifferentiated-type early gastric cancer (UEGC) remains controversial. We aimed to analyze the risk factors for lymph node metastasis (LNM) in UEGC and evaluate the feasibility of ESD.

METHODS

This study included 346 patients with UEGC who underwent curative gastrectomy between January 2014 and December 2021. Univariate and multivariate analyses of the correlation between clinicopathological features and LNM were conducted, and the risk factors for exceeding the expanded ESD indications were evaluated.

RESULTS

The overall LNM rate in UEGC was 19.94%. Among the preoperatively assessable factors, submucosal invasion (odds ratio [OR] = 4.77, 95% confidence interval [CI]: 2.14-10.66) and > 2 cm(OR = 2.49, 95% CI: 1.20-5.15) were independent risk factors for LNM, while postoperative independent risk factors were > 2 cm (OR = 3.35, 95% CI: 1.02-5.40) and lymphovascular invasion(OR = 13.21, 95% CI: 5.18-33.70). Patients who met the expanded indications had a low LNM risk (4.1%). Additionally, tumors located in the cardia (P = 0.03), non-elevated type (P < 0.01) were independent risk factors for exceeding the expanded indications in UEGC.

CONCLUSIONS

ESD may be applicable for UEGC meeting the expanded indications, and preoperative evaluation should be cautious when the lesion is non-elevated type or located in the cardia.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (12/05/2022 ChiCTR2200059841 ).

Endoscopic submucosal dissection versus surgery for patients with undifferentiated early gastric cancer

BACKGROUND AND AIMS

endoscopic submucosal dissection (ESD) is the standard treatment for differentiated early gastric cancer (EGC). However, its expanded indication for undifferentiated EGC is controversial. In this study, the efficacy and safety of ESD versus surgery in patients with undifferentiated EGC were compared.

METHODS

four databases were searched until February 24, 2022, for studies assessing patients with undifferentiated EGC that met an expanded indication for endoscopic resection and who were treated with ESD or surgery. Primary outcomes were all-cause mortality and any recurrence. Secondary outcomes were complete histological resection, local recurrence, metachronous recurrence, synchronous recurrence, distant metastasis, overall complication, and bleeding. All meta-analyses were performed using a random-effects models. Unadjusted (risk ratio [RR]) and adjusted (aRR and hazard ratio [aHR]) estimates with 95 % confidence interval (CI) were calculated.

RESULTS

seven cohort studies were included (n = 2637). The use of ESD was significantly associated with higher all-cause mortality compared to surgery (RR, 2.17; 95 % CI, 1.24-3.81); adjusted all-cause mortality effects were not significant (aRR, 2.28; 95 % CI, 0.95-5.47 and aHR, 1.97; 95 % CI, 0.85-4.53). ESD was associated with a higher risk of any recurrence using unadjusted (RR, 5.24; 95 % CI, 1.49-18.46) and adjusted (aRR, 7.89; 95 % CI, 1.52-40.95 and aHR, 3.73; 95 % CI, 1.17-11.90) estimates. The risk of local recurrence, synchronous recurrence and bleeding were significantly higher for ESD versus surgery. No significant differences were found for other secondary outcomes.

CONCLUSIONS

although ESD is associated with a higher risk of any recurrence, adjusted all-cause mortality is similar during follow-up. Overall complications were similar between ESD and surgery.

Prevalence of Regional Lymph Node Metastasis of Mucosal Gastric Signet Ring Cell Carcinoma: Analysis of the Collaborative Stage Data Survey of the Korean Central Cancer Registry

INTRODUCTION

Patients with very early-stage gastric signet ring cell carcinoma (SRC) are eligible for minimally invasive treatment, like endoscopic submucosal dissection. However, population-based data on regional lymph node metastasis (LNM) and distant metastasis of gastric SRC are lacking. This study aimed to identify the prevalence of LNM and distant metastasis in mucosal cancer (T1a) of gastric SRC.

METHODS

The Collaborative Stage Data Survey was performed by the Korean Center of Cancer Registry between 2010 and 2015 to establish collaborative stage data of the stomach, colon, rectum, rectosigmoid junction, and breast. From the survey data, information on patients with gastric SRC was extracted for analysis. Variables including age, sex, diagnosis date, primary site, tumor size, histology, American Joint Committee on Cancer staging system scores, and Surveillance, Epidemiology, and End Results summary stage were analyzed.

RESULTS

A total of 1,335 (65.7%) patients had mucosal gastric SRC, and 1,189 (89.1%) patients had surgery and 134 (10%) had endoscopic treatment. Of them, 1,283 (96.1%) patients did not have regional LNM, and 52 (3.9%) patients had regional LNM and 6 (0.4%) had distant metastasis. The hazard ratios of LNM and distant metastasis were 14.98 (95% CI: 4.18-53.2) and 10.09 (95% CI: 2.30-44.17).

CONCLUSIONS

Reginal LNM and distant metastasis occur very less in mucosal gastric SRC, but they are associated with an increased risk of cancer-related death. Even in early stage, surgery should be considered as a standard treatment of mucosal gastric SRC.

Efficacy and Feasibility of Magnifying Blue Laser Imaging without Biopsy Confirmation for the Diagnosis of the Demarcation of Gastric Tumors: A Randomized Controlled Study

BACKGROUND

Accurate diagnosis of the demarcation line (DL) of gastric tumors is essential for curative complete resection by endoscopic submucosal dissection (ESD). It is controversial to perform only magnifying endoscopy for diagnosing the DL of gastric tumors prior to ESD. This study aimed to evaluate the diagnostic accuracy for the DL of gastric adenomas and well-differentiated adenocarcinomas using only magnifying blue laser imaging (M-BLI) compared with that using both M-BLI and biopsy confirmation.

METHODS

In this prospective, single-center study, 96 well-differentiated adenocarcinomas and 32 gastric adenomas were enrolled between July 2015 and December 2016. A total of 122 lesions with a clear DL on M-BLI were randomly allocated to undergo M-BLI only (the M-BLI group) or M-BLI with biopsy confirmation (the M-BLI-BC group), performed as biopsies in 4 directions from noncancerous tissues ≈ 5 mm outside the lesion before ESD. The primary end point was to clarify the noninferiority of M-BLI without biopsy confirmation compared with that with biopsy confirmation, in terms of the diagnostic accuracy and complete resection.

RESULTS

There were no significant differences in sex, median age, color, circumference, macroscopic type, biopsy-based diagnosis, and Helicobacter pylori infection between the 2 groups. The diagnostic accuracy for the DL was 100 and 95.0% and the complete resection was 100 and 100% in the M-BLI and M-BLI-BC groups, respectively.

CONCLUSION

The diagnostic ability of M-BLI is excellent in diagnosing the demarcation of gastric adenoma and well-differentiated adenocarcinoma. Biopsy confirmation is not needed for these lesions with a clear DL by M-BLI.

Accuracy of endoscopic size measurements of early gastric signet ring cell carcinoma

BACKGROUND AND AIMS

Indications for endoscopic submucosal dissection (ESD) of early gastric cancer (EGC) are expanding, but signet ring cell carcinoma (SRC) is still unclear because of its unclear boundaries. The purpose of this study was to compare pathologic size and endoscopic size in SRC-type EGC and to find risk factors associated with tumor size underestimation.

METHODS

Medical records of 137 patients diagnosed with SRC-type EGC between January 2009 and December 2016 at our tertiary hospital were reviewed. According to pathologic and endoscopic tumor sizes, they were classified into correct estimation, underestimation, and overestimation groups, and risk factors related to underestimation were analyzed.

RESULTS

Among 137 patients with SRC-type EGC, 77 patients (56.2%) had undergone correct estimation, 43 patients (31.4%) had undergone underestimation, and 17 patients (12.4%) had undergone overestimation. Mean pathologic size (SD) was 20.1 (13.8) mm and mean endoscopic size (SD) was 17.9 (10.1) mm, the correlation coefficients were 0.919 (p < 0.001) , and there was no significant difference between the two groups. Multivariate analysis showed that tumor size more than 20 mm (OR 3.419; 95% CI 1.271-9.194; p = 0.015) and atrophy (OR 6.011; 95% CI 2.311-15.633; p = 0.001) were risk factors for tumor size underestimation.

CONCLUSION

There was no significant difference in pathologic and endoscopic size in SRC-type EGC. Therefore, ESD may be considered as a therapeutic option if the size of the tumor is less than 20 mm and atrophy is not present in the surrounding mucosa.

Undifferentiated-type predominant mixed-type early gastric cancer is a significant risk factor for requiring additional surgeries after endoscopic submucosal dissection

We aimed to clarify the differences in therapeutic outcomes of patients with pure undifferentiated-type and mixed undifferentiated-type cancers who underwent endoscopic submucosal dissection (ESD), and whether pre-treatment diagnosis of mixed undifferentiated-type cancer is associated with requiring additional surgery after ESD. Patients subjected to ESD as initial treatment between May 2005 and March 2017 were enrolled. There were 277 undifferentiated-type cancers (265 patients). Histologically, 258 lesions were pure-type and 19 were mixed-type. We compared therapeutic outcomes and pre-treatment factors (tumour diameter, tumour depth, ulcerative findings, tumour location, and the macroscopic, and histological type of the biopsy specimen) between pure-type and mixed-type lesions, and between cases not requiring additional surgeries and cases requiring additional surgeries. Tumour diameter >20 mm, submucosal invasion, and the presence of ulcerative findings made pre-treatment diagnosis more difficult for mixed-type than for pure-type lesions. In cases requiring additional surgery, pre-treatment diagnosis of mixed-type lesions was significantly more likely than pre-treatment diagnosis of pure-type lesions. For mixed-type lesions, pre-treatment histological diagnosis and careful consideration are necessary to determine indications for ESD to avoid additional surgery after ESD.

Effect of histologic differences between biopsy and final resection on treatment outcomes in early gastric cancer

BACKGROUND AND STUDY AIMS

Biopsy-based histologic diagnosis is important in determining the treatment strategy for early gastric cancer (EGC). However, there are few studies on how histologic discrepancy may affect patients' treatment outcomes. We aimed to investigate the impact of histopathologic differences between biopsy and final specimens from endoscopic resection (ER) or gastrectomy on treatment outcomes in patients with EGC. We also examined the predictive factors of histologic discrepancy.

PATIENTS AND METHODS

We analyzed the data of 1851 patients with EGC treated with ER or gastrectomy. We compared the histology between biopsies and final resected specimens from ER or gastrectomy. We also examined changes in treatment outcomes according to histologic differences.

RESULTS

Histologic discrepancy was observed in 11.9% of patients in the ER group and 10.7% of those in the gastrectomy group. In patients treated with ER who showed histologic discrepancy, 80.9% showed differentiated-type EGC (D-EGC) on biopsy but undifferentiated-type-EGC (UD-EGC) after ER, of which 78.9% were non-curative resection. In patients treated with gastrectomy who showed histologic discrepancy, 39% showed UD-EGC on biopsy but showed D-EGC after gastrectomy. A total of these patients had absolute and expanded indications for ER. Moderately differentiated and poorly differentiated adenocarcinoma on biopsy were predictive factors of histologic discrepancy in UD-EGC and D-EGC on final resection, respectively.

CONCLUSIONS

About 10% of patients showed histologic discrepancy between biopsy and final resection with ER or gastrectomy. Histologic discrepancy can affect treatment outcomes, such as non-curative resection in ER or missing the opportunity for ER in gastrectomy.

Possible indication of endoscopic resection in undifferentiated early gastric cancer

Endoscopic resection for early gastric cancer (EGC) without lymph node metastasis may be a valuable treatment option. To date, endoscopic resection for undifferentiated EGC is being investigated. We evaluated the risk of lymph node metastasis in undifferentiated EGC by examining the preoperative endoscopic findings and operated pathologic specimen. The medical records of patients who underwent surgical resection because of undifferentiated EGC between November 2008 and December 2015 were reviewed retrospectively. The risk factors associated with lymph node metastasis and the lymph node metastasis rate in the expanded indication of undifferentiated EGC were evaluated. A total of 376 patients with undifferentiated EGC (233 signet ring cell type and 143 poorly differentiated type) were analyzed. Lymph node metastasis was found in 9.8% of the patients. Among the patients who met the expanded criteria (59 patients), only one patient had lymph node metastasis (signet ring cell type without ulceration and 15 mm in size). The risk factors associated with lymph node metastasis were lesion size >20 mm (OR 3.013), scar deformity (OR 2.248), surface depression (OR 2.360), submucosal invasion (OR 3.427), and lymphovascular invasion (OR 6.296). Before endoscopic resection of undifferentiated EGC, careful selection of patients should be considered. The undifferentiated EGC with size ≥15 mm, scar deformity, surface depression, submucosal invasion, and lymphovascular invasion should be considered surgical resection instead of endoscopic resection.

A suitable marking method to achieve lateral margin negative in endoscopic submucosal dissection for undifferentiated-type early gastric cancer

Background and study aims  Delineating undifferentiated-type early gastric cancer (UD-type EGC) from noncancerous areas is difficult. Therefore, the lateral margin negative (LM-) resection rate of endoscopic submucosal dissection (ESD) is lower for UD-type EGC than for differentiated-type EGC. This study aimed to retrospectively evaluate the effectiveness of the marking methods with circumferential biopsies in ESD for UD-type EGC. Patients and methods  We analyzed the clinical outcomes of ESD in 127 patients with UD-type EGC between April 2013 and 2017. We performed diagnostic delineation of cancerous areas using magnifying endoscopy with narrow-band imaging, and four or more circumferential biopsies approximately 5 mm apart from the estimated lesion border were obtained to confirm noncancerous areas. The markings were placed on the circumferential biopsy scars, and a mucosal incision line was made outside the markings. Results  Median size of the tumors and ESD specimens was 12 and 35 mm, respectively. En-bloc resection rate was 100 % (127/127), and LM- and curative resection rates were 97.6 % (124/127) and 80.3 % (102/127), respectively. Circumferential biopsy in preoperative esophagogastroduodenoscopy has successfully identified the misdiagnosis of cancerous areas of four patients (3.2 %), with three (2.4%) achieving LM- resection. LM + resection was pathologically identified in three patients (2.4 %), with all undergoing non-curative resection due to > 20-mm tumor. The proportion of patients with the shortest distance ≥ 5 mm from the lesion edge to the specimen edge was 88.2 % (112/127). Conclusion  Our marking methods with circumferential biopsies may reduce LM + resections in ESD for UD-type EGC.

Diagnostic accuracy of demarcation using magnifying endoscopy with narrow-band imaging for Helicobacter pylori-uninfected undifferentiated-type early gastric cancer

BACKGROUND

It is unknown how the accuracy rate of diagnostic demarcation of undifferentiated-type early gastric cancers (UD-type EGCs) differs between patients uninfected with Helicobacter pylori (H. pylori) and patients with and without H. pylori eradication. This study assessed and compared the diagnostic accuracy rate in the H. pylori-uninfected group and the non-H. pylori eradication and H. pylori eradication groups.

METHODS

Subjects were 81 patients with 81 lesions who underwent endoscopic submucosal dissection between January 2010 and January 2015. There were 21 lesions in the H. pylori-uninfected group, 27 in the H. pylori eradication group, and 33 in the non-H. pylori eradication group. The rate in the H. pylori-uninfected group was separately compared with the rates in the non-H. pylori eradication and H. pylori eradication groups, as was inflammatory cell infiltration.

RESULTS

The diagnostic accuracy rates were 60.6% in the non-H. pylori eradication group, 92.2% in the H. pylori eradication group, and 100% in the H. pylori-uninfected group; the rate was significantly higher in the H. pylori-uninfected group than in the non-H. pylori eradication group, but no significant difference was observed between the H. pylori-uninfected group and the H. pylori eradication group. In addition, the H. pylori-uninfected and H. pylori eradication groups showed no significant differences in neutrophil infiltration and intestinal metaplasia, whereas the state in the H. pylori-uninfected group was significantly milder.

CONCLUSIONS

Because neutrophil infiltration was classified as mild or none, the accuracy of diagnostic demarcation was high in the H. pylori-uninfected and H. pylori eradication groups.

Quality in upper gastrointestinal endoscopic submucosal dissection

Progress in the endoscopy technology field led to an increase in the diagnosis of early gastrointestinal (GI) superficial lesions and to an improvement of their treatment. Endoscopic submucosal dissection (ESD) has been developed in Japan with the aim of removing such lesions in one piece, in order to obtain a curative resection and to minimize the risk of local recurrence, and to preserve the native organ. ESD is widely used in Asia for the treatment of early upper and lower GI lesions and is currently gaining attention in Western countries too. However, ESD can be safely performed only by expert endoscopists and in specific clinical settings. Therefore, prior to decide whether ESD is feasible or not, the target lesion must be carefully assessed, in order to understand whether or not it is eligible for submucosal dissection. The aim of this paper is to review indications, limitations and technical aspects of upper GI ESD.

The Characteristics and Prognosis of Diffuse-Type Early Gastric Cancer Diagnosed during Health Check-Ups

Background/Aims

Because of the poor prognosis of diffuse-type gastric cancer, early detection is important. We investigated the clinical characteristics and prognosis of diffuse-type early gastric cancer (EGC) diagnosed in subjects during health check-ups.

Methods

Among 121,111 subjects who underwent gastroscopy during a routine health check-up, we identified 282 patients with 286 EGC lesions and reviewed their clinical and tumor-specific parameters.

Results

Patients with diffuse-type EGC were younger, and 48.1% of them were female. Serum anti-Helicobacter pylori IgG (Hp-IgG) was positive in 90.7% of diffuse-type EGC patients (vs 75.9% of intestinal-type EGC, p=0.002), and the proportion of diffuse-type EGC cases increased significantly with increasing Hp-IgG serum titers (p<0.001). Diffuse-type EGC had pale discolorations on the tumor surface (26.4% vs 4.0% in intestinal-type EGC, p<0.001) and were often located in the middle third of the stomach. Submucosal invasion or regional nodal metastasis was observed more commonly in patients with diffuse-type EGC. However, during the median follow-up period of 50 months, 5-year disease-free survival rates did not differ between the groups.

Conclusions

Diffuse-type EGC shows different clinical and endoscopic characteristics. Diffuse-type EGC is more closely associated with Hp-IgG seropositivity and a higher serum titer. Early detection results in excellent prognosis.

Diagnostic accuracy of demarcation of undifferentiated-type early gastric cancer after Helicobacter pylori eradication

BACKGROUND

It is unknown whether Helicobacter pylori (H. pylori) eradication is beneficial when demarcating undifferentiated-type early gastric cancers (UD-type EGCs). This study aimed to determine whether H. pylori eradication is beneficial, and also when benefits become detectable.

METHODS

Sixty lesions that were detected as a ≤20-mm lesion without metastasis or ulceration on routine examination, diagnosed as UD-type EGC on biopsy, and treated with endoscopic submucosal dissection between January 2010 and January 2015 were studied. Magnifying endoscopy with narrow-band imaging (ME-NBI) was performed to demarcate the lesions. The most oral and most anal sites were marked. After endoscopic therapy, the markings were compared with the pathological examination results to calculate accurate diagnosis rates, which were compared between 27 patients with H. pylori eradication and 33 patients without. Mean intercrypt distance ratio and inflammatory cell infiltration were also compared, as were seven patients who underwent the procedure 1 month after H. pylori eradication and 20 patients who underwent the procedure more than 1 month after H. pylori eradication.

RESULTS

Accurate diagnosis rates were 92.2% with eradication and 60.6% without. Mean intercrypt distance ratios were 1.95 and 1.59, respectively. Neutrophil infiltration was mild in the eradication group. Significant differences were observed in each parameter (p < 0.05). No significant difference was observed between the 1-month eradication and >1-month eradication subgroups in terms of accurate diagnosis rate, mean intercrypt distance ratio, or histological grade of any item.

CONCLUSIONS

This study suggests that H. pylori eradication therapy aids the accurate delineation of UD-type EGC in ME-NBI.

Accuracy of diagnostic demarcation of undifferentiated-type early gastric cancer for magnifying endoscopy with narrow-band imaging: surgical cases

BACKGROUND AND AIM

The usefulness of magnifying endoscopy with narrow-band imaging (ME-NBI) in undifferentiated-type early gastric cancers (UD-type EGCs) is unclear. This study investigated the accuracy of ME-NBI in the diagnostic demarcation.

METHODS

Among UD-type EGCs that were initially surgically resected between June 2011 and August 2014 in this hospital, 74 lesions were studied that were preoperatively diagnosed with white-light imaging (WLI) or endoscopic ultrasonography as lesions for which endoscopic treatment was not indicated and found to be early gastric cancers by postoperative pathology. The demarcation line was marked on the most oral and anal sides with argon plasma coagulation using WLI and ME-NBI, and the diagnostic demarcation of cancer was defined as correct, if consistent with the results of postoperative pathology. The length of extension into the proliferative zone, distance between crypts and inflammatory cell infiltration (updated Sydney classification: USC) were compared between the correctly diagnosed and the misdiagnosed cases.

RESULTS

The diagnosis was correct in 62 cases (83.8 %). The average distance between crypts in correctly diagnosed and misdiagnosed cases was approximately 1.9 and 1.3 times, respectively, that in normal mucosa (p < 0.0001). The accuracy of diagnosis was higher when atrophy and neutrophil and monocyte infiltration were mild according to the USC (p < 0.05). The additional use of ME-NBI improved the accuracy of diagnosis by 36.5 % compared with the use of WLI alone.

CONCLUSION

The use of ME-NBI in the preoperative diagnosis of the demarcation of cancer is useful to prevent postoperative positive surgical margins.

Accuracy of diagnostic demarcation of undifferentiated-type early gastric cancers for magnifying endoscopy with narrow-band imaging: endoscopic submucosal dissection cases

BACKGROUND

The usefulness of magnifying endoscopy with narrow-band imaging (ME-NBI) for undifferentiated-type early gastric cancers (UD-type EGCs) is unclear. The present study examined the accuracy of the diagnostic demarcation of lesions using ME-NBI.

METHODS

The study population consisted of 76 patients with UD-type EGC lesions measuring ≤20 mm in diameter using white-light imaging (WLI) and endoscopic ultrasonography and diagnosed as intramucosa and UL(-); all the lesions were confirmed as early gastric cancer based on postoperative pathological examination. All the patients had undergone an initial endoscopic submucosal dissection (ESD) at this hospital between January 2010 and January 2014. After marking with demarcation lines at the utmost oral and anal sites of the lesion using argon plasma coagulation under ME-NBI for intervention, the cases with demarcations that were consistent with the postoperative pathological findings were defined as having been accurately diagnosed. The inflammatory cell infiltration (Updated Sydney System, USS) were also assessed.

RESULTS

The diagnostic demarcations of the lesion were consistent in 62 cases (81.6 %). The accurate diagnosis rate was higher for the USS cases with mild neutrophil and monocyte infiltration (P < 0.05). The addition of ME-NBI to WLI improved the accurate diagnosis rate by 27.6 %.

CONCLUSION

The use of ME-NBI in diagnostic demarcation of UD-type EGCs is recommended.

Endoscopic Resection for Undifferentiated-Type Early Gastric Cancer: Immediate Endoscopic Outcomes and Long-Term Survivals

BACKGROUND

Endoscopic resection (ER) is considered carefully as a curative treatment option for selected cases of undifferentiated-type early gastric cancer (UEGC). This study investigated immediate endoscopic and long-term survival outcomes of patients with UEGC treated with ER.

METHODS

A review of a database of 2483 EGC consecutively enrolled patients who underwent ER between January 2004 and December 2010 identified 101 patients with UEGC who met the expanded indications. Outcomes were investigated in these patients.

RESULTS

The rates of R0 en bloc and curative resection were 86 and 70 %, respectively. Of 30 tumors non-curatively resected, 17 were larger than 20 mm in diameter, 12 had positive resection margins, and 13 had submucosal or lymphovascular invasion on resection pathology. ER-related complications occurred in 12 patients (12 %), with all complications treated endoscopically without surgery. The median ER procedure time was 26 min [interquartile range (IQR) 20-39 min]. Only tumor location in the lower part of the stomach was significantly associated with curative ER (P = 0.038). Tumor recurrence was observed in seven patients at a median 17 months (IQR 12-47 months) after ER. During a median follow-up of 60 months (IQR 48-80 months), the 5-year overall mortality rates were 5 % in the curative and 4 % in the non-curative resection groups (P = 0.927). There were no gastric cancer-related deaths.

CONCLUSIONS

ER shows acceptable immediate endoscopic and long-term survival outcomes in selected patients with UEGC.

Endoscopic resection for undifferentiated early gastric cancer: focusing on histologic discrepancies between forceps biopsy-based and endoscopic resection specimen-based diagnosis

BACKGROUND

Before endoscopic resection (ER), a considerable number of undifferentiated early gastric cancer (UD-EGC) cases were initially diagnosed as atypical glands, dysplasia, or differentiated EGC (D-EGC) based on forceps biopsy specimens. As UD-EGC carries a high risk of resection margin involvement, identifying the predictive factors for UD-EGC cases with histologic discrepancy (HD) is of clinical importance.

AIMS

To investigate the outcomes of ER for UD-EGC and to identify the predictive factors for UD-EGC with HD.

METHODS

Among 2,194 EGC lesions treated by ER, 59 lesions were finally diagnosed as UD-EGC and 50 UD-EGC cases showed HD. The demographic and endoscopic characteristics were compared between D-EGC and UD-EGC with HD, and the predictive factors for the latter were investigated among cases of forceps biopsy-based diagnosis of atypical glands, dysplasia, or D-EGC.

RESULTS

UD-EGC showed significantly higher rate of lateral margin involvement compared to D-EGC (18.6 vs. 3.4%). Among the UD-EGC cases meeting the expanded criteria and not involving additional surgery, no local or extragastric tumor recurrence was observed during the median follow-up of 27.5 months. Multivariate analysis demonstrated that age (≤60 years), female gender, gastric body, flat or depressed type, and tumor size (>2 cm) were independent predictive factors for UD-EGC with HD among cases of forceps biopsy-based diagnosis of atypical glands, dysplasia, or D-EGC.

CONCLUSIONS

For lesions with predictive factors for UD-EGC with HD, a circumferential mapping biopsy before ER or wide marking during ER could be considered to avoid the potential risk of incomplete resection.

"Crawling-type" adenocarcinoma of the stomach: a distinct entity preceding poorly differentiated adenocarcinoma

BACKGROUND

Gastric "crawling-type" adenocarcinoma (CTAC) is a neoplasm histologically comprising irregularly fused glands with low-grade cellular atypia that tends to spread laterally in the mucosa. It is necessary to elucidate the clinicopathological characteristics of CTAC.

METHODS

We evaluated 25 CTACs-16 intramucosal (M-) and 9 submucosal invasive (SM-) cancers-clinicopathologically and immunohistochemically.

RESULTS

CTAC was most frequently located in the lesser curvature of the middle-third of the stomach. Macroscopically, 21 lesions were superficial-depressed and 4 were superficial-flat type. Histologically, all CTACs had cystic dilated glands and 16 lesions had focal signet-ring cells. All invasive areas of the SM-CTACs were occupied by poorly differentiated adenocarcinoma with an infiltrative growth pattern and abundant stroma. Fifteen CTACs were surrounded by mucosa with partial or no intestinal metaplasia. In the intramucosal area, 24 lesions were mixed phenotype with mucin and brush border immunoexpression. SM-CTAC was frequent in lesions with an intramucosal poorly differentiated component (PDC) greater than 10 mm in size (P = 0.041), and lymph node metastasis (LNM) was frequent in lesions with a PDC greater than 20 mm (P = 0.039). The frequency of an expanded pattern (Ki-67-positive cells occupying > 50 % of the mucosa) was higher in SM-CTAC than in M-CTAC (P = 0.027). p53 overexpression was not detected in the intramucosal areas of any of the lesions.

CONCLUSION

CTAC is a distinct subgroup of gastric adenocarcinoma in the early phase. A larger PDC and a Ki-67 expanded pattern were predictive of submucosal invasion or LNM.

Depressed type of intramucosal differentiated-type gastric cancer has high cell proliferation and reduced apoptosis compared with the elevated type

BACKGROUND

The depressed type of early gastric cancer, in comparison to the elevated type, tends to invade the submucosal layer and metastasize to the lymph nodes. This study compared the differences in tumor cell proliferation and apoptosis between the elevated and depressed types of intramucosal differentiated gastric cancer.

METHODS

A total of 57 intramucosal differentiated gastric cancers were studied. Twenty samples were the elevated type and 37 were the depressed type. The tumor cells were analyzed by immunohistochemistry for Ki-67, Bcl-2, and Bax, and terminal deoxynucleotidyl transferase 2´-deoxyuridine, 5´-triphosphate (dUTP)-biotin nick end labeling was carried out to detect apoptotic cells.

RESULTS

(1) The Ki-67 labeling index (KI) was higher in the depressed type (median: 38.6) than in the elevated type (median: 21.2). (2) Immunopositivity for Bax and the apoptosis index (AI) were lower in the depressed type (median AI: 0.20) than the elevated type (median AI: 1.05). (3) The AI/KI was lower in the depressed type (median: 0.17) than in the elevated type (median: 5.57). (4) The AI in the tumors with a Bcl-2-negative and Bax-positive pattern (median: 2.0) was higher than that in the tumors with a Bcl-2-positive and Bax-negative pattern (median: 0.2).

CONCLUSION

These results show that, regarding cell proliferation and apoptosis, the depressed type of intramucosal differentiated-type gastric cancer has high malignant potential in comparison to the elevated type.

Diagnosis of undifferentiated type early gastric cancers by magnification endoscopy with narrow-band imaging

BACKGROUND AND AIMS

  The diagnostic use of magnification endoscopy with narrow-band imaging (ME-NBI) to assess histopathologically undifferentiated-type early gastric cancers (UD-type EGCs) is not well elucidated. The purpose of this study was to examine the comparative relationship between ME-NBI images and histopathological findings in UD-type EGCs.

METHODS

  We analyzed 78 consecutive cases of UD-type EGCs ≤ 20 mm in diameter that underwent ME-NBI ≤ 2 weeks prior to resection. The ME-NBI images were compared with histopathological findings following either endoscopic submucosal dissection (ESD) or surgery. Applying the comparative results, we prospectively evaluated the success of identifying the lateral extent of UD-type EGCs resected by ESD in additional consecutive cases.

RESULTS

  Lesions with preserved but irregular surface microstructures (S-type based on ME-NBI) showed mucosal atrophy and corresponded histologically to the non-whole-layer type of intramucosal cancer (24/24, 100%). Lesions with an irregular microvasculature type (V-type, for example, corkscrew pattern) or mixed type upon ME-NBI corresponded histopathologically to the non-whole-layer type of intramucosal cancer (15/54, 27.8%), the whole-layer type of intramucosal cancer (27/54, 50.0%) or submucosal (sm) invasion cancer (12/54, 22.2%). Applying these comparative results, we used ME-NBI to successfully predict the lateral extent of cancer, which corresponded to the histopathological lateral extent in all 18 additional consecutive UD-type EGCs resected by ESD.

CONCLUSIONS

  ME-NBI images of UD-type EGCs were very closely related to the histopathological findings. Thus, ME-NBI can be useful in the pretreatment assessment of the histopathological patterns of cancer development and the lateral extent of such lesions.

Expansion of indications for endoscopic treatment of undifferentiated mucosal gastric cancer: analysis of intramucosal spread in resected specimens

PURPOSE

The aim of this study was to pathologically investigate the developmental pattern of undifferentiated mucosal gastric cancer and to determine safe surgical margins for curative resection by endoscopic resection.

RESULTS

Intramucosal cancer spread, or the width of the proliferative zone, was pathologically investigated in 47 cases of undifferentiated mucosal gastric cancer of size 20 mm or smaller without ulceration (scars). The 47 cases comprised 40 IIc and 7 IIb cases. The IIc cases consisted of 5 (12.5%) of intermediate-layer type (cancer localized at the intermediate layer of the mucosa), 31 (77.5%) of superficial type, and 4 of whole-layer type (10%). The IIb cases consisted of six of intermediate-layer type (85.7%) and one of superficial type (14.3%). The width of the proliferative zone in the 40 IIc cases ranged from 0 to 2,390 microm (average 605.5 microm). There was no significant correlation between width of proliferative zone and background mucosa. With regard to lesion size, average width was 243.6 microm in cases with longest diameter <or=5 mm, while it was significantly larger (617.1 microm) in cases with diameter >5 mm.

CONCLUSIONS

In endoscopic treatment of undifferentiated mucosal gastric cancer of size 20 mm or smaller without ulceration (scars), the lateral safety margin should be 3 mm or more.

Therapeutic outcomes of endoscopic submucosal dissection of undifferentiated-type intramucosal gastric cancer without ulceration and preoperatively diagnosed as 20 millimetres or less in diameter

AIM

The aim of the present study was to examine therapeutic outcomes of endoscopic submucosal dissection (ESD) of undifferentiated-type intramucosal gastric cancer and the problems of diagnosis.

METHODS

We reviewed 58 patients with preoperatively diagnosed undifferentiated-type intramucosal early gastric cancer (EGC) without ulceration with a diameter of 20 mm or smaller (expanded-indication lesion) who underwent ESD at the Cancer Institute Hospital between September 2003 and August 2008.

RESULTS

The overall rates of one-piece resection and complete resection were 98% and 90% respectively, and the median operation time was 70 min. Bleeding was seen in 8.6% and perforation in 3.4%. The curative resection rate was low at 79%. Factors responsible for non-curative resection were most commonly submucosal invasions. If limited to pathologically diagnosed expanded-indication lesions, the curative resection rate was 98%. The difference in tumor size between a macroscopic diameter and a histological diameter was within +/-5 mm in 96% of expanded-indication lesions, with none of these cases having a histological diameter that exceeded the macroscopic diameter by more than 5 mm.

CONCLUSION

ESD was technically feasible for expanded-indication lesions of undifferentiated-type EGC. We achieved a high rate of curative resection by the markings at sites 5 mm beyond the preoperatively determined lesion area. Factors responsible for non-curative resection were most commonly submucosal invasions. We should diagnose the depth of such lesions more carefully.

Endoscopic mucosal resection

Endoscopic mucosal resection (EMR) is a promising therapeutic option for removal of superficial carcinomas or premalignant lesions throughout the gastrointestinal tract. This review discusses indications and the several techniques of EMR in early tumors of esophagus, stomach, duodenum, and colon. EMR is not yet widely utilized in the West. However, great benefits may be obtained from this non-invasive technique after an accurate evaluation of patients and a careful staging of lesions that may assess the depth of infiltration and exclude the presence of lymph node metastases. EMR permits a complete removal of the lesion with histologic assessment of the entire specimen and the change in the pathologic stage in a significant number of patients. To minimize the risk of serious complications (mostly bleeding and perforation), only experienced endoscopists should undertake EMR in an appropriate environment. Data from literature are encouraging on the use of EMR, but a long-term follow-up of a large number of patients is necessary to confirm the effectiveness of this therapy.

E-cadherin expression as predictive marker of proximal resection line involvement for advanced carcinoma of the gastric cardia

AIMS

Total gastrectomy for gastric cardia tumours harbours a high risk of proximal resection line (PRL) involvement. The adhesion markers CD44v6 and E-cadherin were evaluated as predictive factors for PRL involvement independent of tumour stage.

METHODS

Forty-nine gastrectomy specimens for gastric cardia carcinoma (type II) were evaluated for stage, resection margins, and CD44v6 and E-cadherin immunohistochemistry.

RESULTS

PRL involvement was microscopically recognized in 49% of specimens. CD44v6 expression was found in 84% of intestinal tumours, and in 56% of diffuse/mixed tumours (p=0.045). In the group of resections performed with curative intent, the proximal extension of the resection (margin) was significantly shorter in E-cadherin negative tumours than in E-cadherin positive tumours (p=0.029). Histological type and stage of the tumour, lymph node metastases, and absence of E-cadherin expression, but not the presence of CD44v6 correlated with PRL involvement. Only the absence of E-cadherin expression appeared to be a significant predictor of PRL involvement, independent of tumour stage. Survival for patients with PRL involvement was shorter than that for patients after R0 resection (p=0.07). Stage was the only independent prognostic factor emerging from multivariate survival analysis (p=0.002).

CONCLUSIONS

When curative resection is intended in type II cardiac cancer patients, an oesophageal resection and gastric tube reconstruction should be considered, especially for a tumour without E-cadherin expression.

Difference of tumor size between endoscopic estimation and postoperative pathological measurement in early gastric carcinoma

AIM: To study the difference of tumor size between endoscopic estimation and postoperative patholoigical measurement in early stage of gastric carcinoma.

METHODS: The size of lesion was estimated by biopsy forceps at endoscopy and by postoperative pathological measurement in 118 patients with early gastric cancer. The correlation between clinicopathological features and measuring errors were analyzed.

RESULTS: Through two different ways of measurement, there was coincidence in 26 of 118 cases (22.0%), and unconformity in 92 of 118 cases (77.9%). The size estimated by biopsy forceps at endoscopy was smaller than by postoperative pathological measurement. In histological study, the measuring error rate was higher in the lowly-differentiated type than that in the highly-differentiated type.

CONCLUSION: There were significant measuring errors in tumor size between endoscopic estimation and pathological measurement in depressed and lowly-differentiated type. The tumor size was smaller in endoscopic estimation than that in the postoperative pathological measurement. This measuring error may be associated with the biological feature of gastric cancer, except the experiences of endoscopists.