Where has the tumor gone? The characteristics of cases of negative pathologic diagnosis after endoscopic mucosal resection

Predictive Model of Nonneoplastic Pathology after Endoscopic Resection of Gastric Epithelial Neoplasia

Background/Aims

The rate of nonneoplastic pathology (NNP) after endoscopic resection (ER) of gastric epithelial neoplasia (GEN) has been reported to be 3%–7%. However, to date, the associations of pretreatment characteristics with NNP have not been identified. The aim of this study was to develop a predictive model for NNP after ER.

Methods

Among 817 patients who underwent ER for GEN, factors associated with NNP were identified by univariate and multivariate analyses. Weighted points considering the β coefficient were allocated to each variable that was significant in the multivariate analysis. The predictive score was calculated by the total points. The area under the receiver operating characteristic curve (AUROC) was calculated for the predictive score.

Results

The rate of NNP was 8.8%. After multivariate analysis, poor demarcation from the background, no ulceration, a flat appearance, and low-grade dysplasia were significant factors predictive of NNP. One point each was allocated for no ulcer, flat appearance, and low-grade dysplasia. Two points were allocated for poor demarcation from the background. The predictive score ranged from 0 to 5 points. Patients were categorized as being at low risk (0, 1, or 2 points) or high risk (3, 4, or 5 points) for NNP. The AUROC was 0.82 (95% confidence interval, 0.77 to 0.88; p<0.01). With a cutoff value of 2.5, the sensitivity and specificity of the score for predicting NNP were 0.72 and 0.84, respectively.

Conclusions

We developed a model to predict NNP after ER. Endoscopic re-biopsy or re-evaluation by pathologists is strongly recommended for the high-risk group.

Negative pathology after endoscopic resection of gastric epithelial neoplasms: importance of pit dysplasia

BACKGROUND/AIMS

Endoscopic resection (ER) is a well-established treatment modality for gastric epithelial neoplasm. However, there is a discrepancy between forceps biopsy and ER specimen pathology, including a negative pathologic diagnosis (NPD) after ER. It has been suggested that pit dysplasia (PD) is a subtype of gastric dysplasia, and the aim of this study was to assess the significance of PD in cases with NPD after ER for early gastric neoplasms.

METHODS

After ER, 29 NPD lesions that had an associated pretreatment forceps biopsy specimen, were correctly targeted during ER, and had no cautery artifact on the resected specimen were included in this study.

RESULTS

Sixteen lesions showed PD and 13 had no neoplastic pathology. The initial pretreatment forceps biopsy diagnoses of 29 NPD lesions were low-grade dysplasia (LGD) in 17 lesions, high-grade dysplasia (HGD) in seven lesions, and adenocarcinoma in five lesions, which after review were revised to PD in 19 lesions, LGD in four lesions, adenocarcinoma in two lesions, and no neoplastic pathology in four lesions. Overall, nine lesions (31%) were small enough to be removed by forceps biopsy, four NPD lesions (14%) were initially misinterpreted as neoplastic lesions, and 16 PD lesions (55%) were misinterpreted as NPD lesions on ER slides.

CONCLUSIONS

Approximately half of the lesions initially diagnosed as LGD or HGD were subsequently classified as PD. Therefore, including PD as a subtype of gastric dysplasia could reduce the diagnostic discrepancy between initial forceps biopsy and ER specimens.

Long-Term Outcome After Endoscopic Submucosal Dissection for Early Gastric Cancer in Non-neoplastic Pathology Results

BACKGROUND

After endoscopic submucosal dissection (ESD) for early gastric cancer (EGC), negative pathological findings cause concern about the adequacy of the procedure and local recurrence after ESD.

AIM

To investigate the incidence of local recurrence in cases with negative pathological findings after ESD for EGC and pathologically complete resection (CR) during long-term follow-up.

METHODS

We reviewed 453 patients who underwent ESD for ECG from January 2007 to December 2010, respectively. Of these patients, in 17 cases the pathology results confirmed no residual tumor (NRT), and in 421 cases they showed CR in the ESD specimen. Finally, 17 NRT and 358 CR cases were followed up during surveillance. Patient characteristics, endoscopic and pathological data were analyzed for risk factors of local recurrence. We also re-evaluated the pathology of the NRT group to identify hidden malignant cells in the previous ESD specimens.

RESULTS

There was no difference between the two groups in terms of recurrence during follow-up surveillance (median 55.7 months). Late local recurrence of EGC was found in two cases (11.8%) in the NRT group, and three early local recurrences (5.6%) were found in the CR group. A review of the pathology in the NRT group revealed hidden malignant cells in five patients (29.4%).

CONCLUSIONS

Even when the pathological report indicates NRT after ESD, it might be necessary to re-evaluate ESD specimens with a width <2 mm, and long-term endoscopic surveillance should be routinely used for detecting local EGC recurrence after ESD.

Retrospective study: The diagnostic accuracy of conventional forceps biopsy of gastric epithelial compared to endoscopic submucosal dissection (STROBE compliant)

Conventional forceps biopsy (CFB) is the most popular way to screen for gastric epithelial neoplasia (GEN) and adenocarcinoma of gastric epithelium. The aim of this study was to compare the diagnostic accuracy between conventional forceps biopsy and endoscopic submucosal dissection (ESD).Four hundred forty-four patients who finally undertook ESD in our hospital were enrolled from Jan 1, 2009 to Sep 1, 2015. We retrospectively assessed the characteristics of pathological results of CFB and ESD.The concordance rate between CFB and ESD specimens was 68.92% (306/444). Men showed a lower concordance rate (63.61% vs 79.33%; P = 0.001) and concordance patients were younger (P = 0.048). In multivariate analysis, men significantly had a lower concordance rate (coefficient -0.730, P = 0.002) and a higher rate of pathological upgrade (coefficient -0.648, P = 0.015). Locations of CFB did not influence the concordance rate statistically.The concordance rate was relatively high in our hospital. According to our analysis, old men plus gastric fundus or antrum of CFB were strongly suggested to perform ESD if precancerous lesions were found. And young women with low-grade intraepithelial neoplasia could select regular follow-up.

Diagnostic group classifications of gastric neoplasms by endoscopic resection criteria before and after treatment: real-world experience

BACKGROUND AND STUDY AIMS

There are often discrepancies between the pretreatment evaluation of gastric neoplasms by endoscopy with biopsy and the final diagnosis of resected specimen in terms of pathology and depth of invasion. We evaluated the spectrum of discrepancies between pretreatment and posttreatment diagnosis which may deliver significant differences on clinical practice.

PATIENTS AND METHODS

A total of 2041 patients with gastric dysplasia or cancer who underwent curative endoscopic resections or surgeries in 2012 were enrolled. Patients were classified into five different diagnostic groups: low-grade dysplasia (LGD), high-grade dysplasia (HGD), absolute indication early gastric cancer (AI-EGC), beyond absolute indication early gastric cancer (BAI-EGC), and advanced gastric cancer (AGC). The choice of initial treatment and final pathologic diagnosis was analyzed.

RESULTS

The study patients belonged to the following pretreatment diagnostic groups: LGDs in 162, HGDs in 164, AI-EGCs in 396, BAI-EGCs in 824, and AGCs in 495 cases. Posttreatment diagnostic groups were LGDs in 140, HGDs in 121, AI-EGCs in 322, BAI-EGCs in 947, AGCs in 505, and no residual tumor in 6 cases. In general, 6.9 % (141/2041) of cases were downgraded and 15.9 % (324/2041) were upgraded. Thirty-four percent of pretreatment HGDs (56/164) were changed to cancers after endoscopic resection. Thirty-three percent of pretreatment AI-EGCs (131/396) were regrouped as posttreatment BAI-EGCs. The additional surgery rate in each pretreatment group was 0.6 % in LGD, 4.3 % in HGD, 15.7 % in AI-EGC, 23.6 % in BAI-EGC among the patients with initial endoscopic resection (p < 0.01).

CONCLUSIONS

Twenty-three percent of gastric neoplasms changed in their final diagnostic group after endoscopic resection or surgery. This discrepancy should be considered when the initial treatment strategy is being selected.

Clinical outcomes of no residual disease in the specimen after endoscopic resection for gastric neoplasms

BACKGROUND

No residual disease (NRD) can be found in the specimen after endoscopic resection (ER) of biopsy-proven gastric neoplasm. This study aimed to evaluate the endoscopic and pathologic characteristics of patients with NRD and identify the cause and long-term prognosis.

METHODS

Medical records of patients who underwent ER for biopsy-proven gastric neoplasms at a single tertiary hospital between January 2005 and November 2014 were retrospectively reviewed. Patients whose post-ER histology was revealed as NRD were included. Overall incidence, clinicopathologic characteristics, cause, and long-term prognosis were analyzed.

RESULTS

NRD was detected in 143 (3.2%) of 4401 cases of gastric neoplasms treated with ER. Mean endoscopic size of the initial lesion was 8.15 ± 6.64 mm; in 93 cases (65.0%), the lesion was located in the lower third of the stomach. Initial pathologic diagnosis was as follows: adenoma (n = 110), carcinoma (n = 29), and atypical gland (n = 4). The causes of NRD were minute lesions removed by biopsy in 140 patients, pathologic misdiagnoses in two, and localization error in one. Local recurrence was detected in five patients (3.6%) with minute lesions during follow-up and treated with argon plasma coagulation (n = 4) or re-ER (n = 1). Synchronous (n = 5, 3.6%) and metachronous gastric lesions (n = 6, 4.3%) were also detected during follow-up.

CONCLUSIONS

The main cause of NRD was minute lesions which might be completely removed by initial diagnostic biopsy. These cases showed a minimal rate of local recurrence and synchronous or metachronous gastric neoplasms. Careful follow-up is also mandatory for detection of residual disease.

A randomized trial to determine the diagnostic accuracy of conventional vs. jumbo forceps biopsy of gastric epithelial neoplasias before endoscopic submucosal dissection; open-label study

BACKGROUND AND AIMS

Larger biopsy specimens or increasing the number of biopsies may improve the diagnostic accuracy of gastric epithelial neoplasia (GEN). The aims of this study was to compare the diagnostic accuracies between conventional and jumbo forceps biopsy of GEN before endoscopic submucosal dissection (ESD) and to confirm that increasing the number of biopsies is useful for the diagnosis of GEN.

RESULTS

The concordance rate between EFB and ESD specimens was not significantly different between the two groups [83.1 % (54/65) in JG vs. 79.1 % (53/67) in CG]. On multivariate analyses, two or four EFBs significantly increased the cumulating concordance rate [coefficients; twice: 5.1 (P = 0.01), four times: 5.9 (P = 0.02)]. But, the concordance rate was decreased in high grade dysplasia (coefficient -40.32, P = 0.006).

PATIENTS AND METHODS

One hundred and sixty GENs from 148 patients were randomized into two groups and finally 67 GENs in 61 patients and 65 GENs in 63 patients were allocated to the conventional group (CG) or jumbo group (JG), respectively. Four endoscopic forceps biopsy (EFB) specimens were obtained from each lesion with conventional (6.8 mm) forceps or jumbo (8 mm) forceps. The histological concordance rate between 4 EFB specimens and ESD specimens was investigated in the two groups.

CONCLUSIONS

Before ESD, the diagnostic accuracy of GENs was significantly increased not by the use of jumbo forceps biopsy but by increasing the number of biopsies.

[Clinicopathologic features of cases with negative pathologic results after endoscopic submucosal dissection]

BACKGROUND/AIMS

Endoscopic submucosal dissection (ESD) is accepted as a standard treatment of early gastric cancer (EGC) and gastric adenoma. Occasionally, tumorous lesion is not found and pathologic discrepancies can occur after ESD. The aim of this study was to analyze the factors affecting the negative pathologic results after ESD.

METHODS

We retrospectively reviewed the data from all patients with gastric neoplasm (276 EGC and 516 gastric adenomas) who were treated with ESD during past 3 years and enrolled the patients who had negative pathologic results.

RESULTS

Out of 792 patients treated with ESD, 27 patients (3.4%) were eligible for inclusion. Among the 27 patients, factors affecting the negative pathologic results were, most commonly, the focal lesion (n=13, 48.2%) which was small enough to be removed completely during pre-ESD biopsy, followed by pathologic discrepancies (n=11, 40.7%) between pathologists and lastly the operator factor (n=3, 11.1%) dissecting incorrect lesions. Of the focal lesions, the initial pathologic diagnoses were adenocarcinoma in 11 cases (84.6%). In cases with pathologic discrepancies, all the pretreatment diagnoses were adenoma with low grade dysplasia. In cases caused by operator factors, intestinal metaplasia was accompanied by elevated adenoma in all cases.

CONCLUSIONS

To decrease negative pathologic results after ESD, an endoscopist should perform ESD after sufficient communication with pathologists, especially for adenoma with low grade dysplasia, and choose correct lesion, especially located at the antrum and associated with intestinal metaplasia. The possibility of total removal of small lesions even by forcep biopsy should be considered.

Rescue endoscopy to identify site of gastric dysplasia or carcinoma found at random biopsies

BACKGROUND

Incidental findings of high-grade dysplasia or gastric cancer at random biopsies with endoscopic diagnosis of chronic gastritis constitute a serious problem to clinical management of patients and sometimes requires blind gastrectomy.

AIM

To evaluate diagnostic value of second-look endoscopy, called "rescue endoscopy", in order to identify focal lesions containing neoplastic changes.

METHODS

Over a three-year period, 20 patients underwent rescue endoscopy using advanced endoscopy and mapping technique. All mucosal irregularities were identified and the locations of these areas were mapped onto a schematic diagram of gastric anatomy. Each area was biopsied and samples included in individually marked specimen containers, to evaluate the correlation between macroscopic and microscopic diagnosis.

RESULTS

Rescue endoscopy identified a total of 68 focal lesions, 18 of which were focal areas of high-grade dysplasia (13 patients) or gastric cancer (5 patients). Two patients had no dysplastic change identified by our targeted biopsies. A second pathologist's opinion confirmed absence of dysplasia on random and targeted biopsies. All patients underwent a median follow-up of 15.2 months (2.6-43.5), and no residual or metachronous lesions were identified.

CONCLUSIONS

In our experience, rescue endoscopy is highly effective in localizing undetermined areas of high-grade dysplasia or carcinoma.

Upgrade of Lesions Initially Diagnosed as Low-Grade Gastric Dysplasia upon Forceps Biopsy Following Endoscopic Resection

Background/Aims

Gastric dysplasia is generally accepted to be the precursor lesion of gastric carcinoma. Approximately 25% to 35% of histological diagnoses based on endoscopic forcep biopsies for gastric dysplastic lesions change following endoscopic resection (ER). The aim of this study was to determine the predictive endoscopic features of high-grade gastric dysplasia (HGD) or early gastric cancer (EGC) following ER for lesions initially diagnosed as low-grade dysplasia (LGD) by a forceps biopsy.

Methods

To determine predictive variables for upgraded histology (LGD to HGD or EGC). The lesion size, gross endoscopic appearance, location, and surface nodularity or redness as well as the presence of a depressed portion, Helicobacter pylori infection, and intestinal metaplasia were retrospectively investigated.

Results

Among 251 LGDs diagnosed by an initial forceps biopsy, the diagnoses of 100 lesions (39.8%) changed following the ER; 56 of 251 LGDs (22.3%) were diagnosed as HGD, 39 (15.5%) as adenocarcinoma, and 5 (2.0%) as chronic gastritis. In a univariate analysis, large lesions (>15 mm), those with a depressed portion, and those with surface nodularity were significantly correlated with a upgraded histology classification following ER. In a multivariate analysis, a large size (>15 mm; odds ratio [OR], 2.8; 95% confidence interval [CI], 1.46 to 5.43) and a depressed portion in the lesion (OR, 2.7; 95% CI, 1.44 to 5.03) were predictive factors for upgraded histology following ER.

Conclusions

Our study shows that a substantial proportion of diagnoses of low-grade gastric dysplasias based on forceps biopsies were not representative of the entire lesion. We recommend ER for lesions with a depressed portion and for those larger than 15 mm.

Endoscopic management of gastric dysplasia: Cutting edge technology needs a new paradigm

There has been tremendous progress in endoscopic techniques for the management of premalignant or malignant gastric lesions. Gastric cancer remains the second most common cause of cancer related mortality worldwide. This means that there is a need for early detection and diagnosis of premalignant lesions or early cancer in clinical practice. Despite substantial development of endoscopic resection techniques, the management of gastric premalignant lesions is controversial because of the lack of consensus and accurate risk stratification. Future study of various aspects would clarify these issues but in the meantime we should reconsider the current algorithm approach for the management of gastric low grade dysplasia.

Is endoscopic forceps biopsy enough for a definitive diagnosis of gastric epithelial neoplasia?

BACKGROUND AND AIM

Endoscopic forceps biopsy (EFB) as the primary histological diagnosis of gastric epithelial neoplasia (GEN) is debated in the era of endoscopic resection (ER). Our aim was to investigate the diagnostic reliability of EFB in patients with GEN compared with ER specimens as the reference standard for the final diagnosis in a large consecutive series.

METHODS

This was a cross-sectional retrospective study at a tertiary-referral center. A total of 354 consecutive patients with 397 GENs underwent ER (endoscopic mucosal resection or endoscopic submucosal dissection). Discrepancy rates between the histological results from EFB and ER specimens were assessed. Discrepancies that could affect patient outcome or clinical care were considered major.

RESULTS

The overall histological discrepancy rate between EFB and ER specimens was 44.5% (95% confidence interval [CI], 39.7-49.5%) among the enrolled patients. The overall discrepancy rate was significantly higher in the intraepithelial neoplasia (IEN) group than in the carcinoma group (49.8% vs 25.6%, P < 0.001). The major discrepancy rate was also significantly higher in the IEN group than in the carcinoma group (36.6% vs 7.0%, P < 0.001). In subgroup analysis of the IEN group, a major histological discrepancy rate of 33.6% (70/208) for low-grade and 42.7% (44/103) for high-grade IEN was found, respectively.

CONCLUSIONS

Endoscopic forceps biopsy was insufficient for a definitive diagnosis and therapeutic planning in patients with GEN. ER should be considered as not only definitive treatment but also a procedure for a precise histological diagnosis for lesions initially assessed as GEN by forceps biopsy specimens.