Has the accuracy of preoperative diagnosis improved in cases of early-stage gastric cancer?

Quality of life comparison between esophagogastrostomy and double tract reconstruction for proximal gastrectomy assessed by Postgastrectomy Syndrome Assessment Scale ( PGSAS )‐45

Aim

The current study compared the postoperative quality of life (QOL) between the esophagogastrostomy method (PGEG) and double tract method (PGDT) after proximal gastrectomy using the Postgastretomy Syndrome Assessment Scale (PGSAS)-45.

Methods

Among the 2364 patients who received the PGSAS-45 questionnaire, 300 PGEG and 172 PGDT cases responded. The main outcomes measures (MOMs) consisted of seven subscales (SS) covering symptoms, meals (amount and quality), ability to work, dissatisfaction with daily life, physical and mental component summary of the 8-Item Short Form Health Survey (SF-8), and change in body weight, and were compared between PGEG and PGDT.

Results

Overall, PGDT promoted significantly better constipation SS scores (p < 0.05), whereas PGEG tended to promote better body weight (BW) loss% (p < 0.10). A stratified analysis based on the remnant stomach size revealed that among those with a remnant stomach size of 1/2, PGDT had significantly better constipation and dumping SS scores (p < 0.05) and tended to have better working conditions (p < 0.10) compared to PGEG. Even among those with the remnant stomach size of 2/3, PGDT had significantly better diarrhea SS scores, lesser dissatisfaction with symptoms, and better dissatisfaction with daily life SS scores (p < 0.05) and tended to have better constipation SS scores and lesser dissatisfaction with work (p < 0.10) compared to PGEG.

Conclusions

After comparing the QOLs of PGEG and PGDT, the stratified analysis according to remnant stomach sizes of 1/2 and 2/3 revealed that PGDT was relatively superior to PGEG for several MOMs.

Superiority of [68Ga]Ga-FAPI-04/[18F]FAPI-42 PET/CT to [18F]FDG PET/CT in delineating the primary tumor and peritoneal metastasis in initial gastric cancer

OBJECTIVE

This study aimed to compare [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT with [¹⁸F]FDG PET/CT in the evaluation of initial gastric cancer.

METHODS

We retrospectively compared [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT with [¹⁸F]FDG PET/CT in patients with initial gastric cancer from September 2020 to March 2021. Lesion detectability and the uptake of lesions quantified by the maximum standardized uptake value (SUVmax) and target-to-background ratio (TBR) were compared between the two modalities using the Wilcoxon signed-rank test, Mann-Whitney U test, and McNemar's chi-square test.

RESULTS

A total of 61 patients (37 males, aged 23-81 years) were included, of which 22 underwent radical gastrectomy. For primary lesions, higher uptake of [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 was observed compared to [¹⁸F]FDG (median SUVmax, 14.60 vs 4.35, p < 0.001), resulting in higher positive detection using [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT than [¹⁸F]FDG PET/CT (95.1% vs 73.8%, p < 0.001), particularly for tumors with signet-ring cell carcinoma (SRCC) (96.4% vs 57.1%, p < 0.001). [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT detected more positive lymph nodes than [¹⁸F]FDG PET/CT (637 vs 407). However, both modalities underestimated N staging compared to pathological N staging. [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT showed a higher sensitivity (92.3% vs 53.8%, p = 0.002) and peritoneal cancer index score (18 vs 3, p < 0.001) in peritoneum metastasis and other suspect metastases compared to [¹⁸F]FDG PET/CT.

CONCLUSION

Our findings indicate that [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT outperformed [¹⁸F]FDG PET/CT in the evaluation of primary tumors with SRCC and peritoneum metastasis in initial gastric cancer. However, no clinically useful improvement was seen in N staging.

KEY POINTS

• The uptake of [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 in primary tumor and metastasis was intensely higher than that of [¹⁸F]FDG (p < 0.001) in 61 patients with initial gastric cancer. • [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT had a higher sensitivity detection in primary tumors (95.1% vs 73.8%, p < 0.001) and peritoneal metastases (92.3% vs 53.8%, p = 0.002) than [¹⁸F]FDG PET/CT. • [⁶⁸Ga]Ga-FAPI-04/[¹⁸F]FAPI-42 PET/CT depicted more positive lymph nodes than [¹⁸F]FDG PET/CT (637 vs 407); however, both underestimated N staging compared to pathological N staging.

Preoperative prediction of the pathological stage of advanced gastric cancer by 18F-fluoro-2-deoxyglucose positron emission tomography

In recent years, the usefulness of neoadjuvant chemotherapy for resectable advanced gastric cancer, particularly stage III, has been reported. Preoperative staging is mainly determined by computed tomography (CT), and the usefulness of ¹⁸F-fluoro-2-deoxyglucose positron emission tomography/CT (FDG-PET/CT) for gastric cancer has been limited in usefulness. The study aimed to evaluate the usefulness of FDG-PET/CT in preoperative diagnosis of advanced gastric cancer. We retrospectively enrolled 113 patients with gastric cancer who underwent preoperative FDG-PET/CT. All patients underwent gastrectomy with lymph-node dissection. The maximum standardized uptake value (SUVmax) of the primary tumor (T-SUVmax) and lymph nodes (N-SUVmax) were measured for all patients. The cutoff values of T-SUVmax for pathological T3/4 from receiver operating characteristic analysis were 8.28 for differentiated and 4.32 for undifferentiated types. The T-SUVmax and N-SUVmax cutoff values for pathological lymph-node metastasis were 4.32 and 1.82, respectively. Multivariate analysis showed that T-SUVmax for differentiated types was a significant predictor of pathological T3/4, and N-SUVmax was a significant predictor of lymph-node metastasis. In conclusion, the SUVmax of FDG-PET/CT was a useful predictor of pathological T3/4 and lymph-node metastasis in gastric cancer. The diagnosis by preoperative FDG-PET/CT is promising to contribute a more accurate staging of gastric cancer than by CT scan alone.

Accuracy of 18F-FDG PET/CT and CECT for primary staging and diagnosis of recurrent gastric cancer: A meta-analysis

Contrast-enhanced computed tomography (CECT) is commonly used for staging and diagnosing recurrent gastric cancer. Recently, 18F-fluorodeoxyglucose positron emission tomography (18F-FDG PET)/CT gained popularity as a diagnostic tool owing to advantages including dual functional and anatomical imaging, which may facilitate early diagnosis. The diagnostic performance of 18F-FDG PET/CT and CECT has been assessed in several studies but with variable results. Therefore, the present meta-analysis aimed to evaluate the accuracy of 18F-FDG PET/CT and CECT for primary TNM staging and the diagnosis of recurrent gastric cancers. A systematic search of the PubMed Central, Medline, Scopus, Cochrane and Embase databases from inception until January 2020 was performed. The Quality Assessment of Diagnostic Accuracy Study-2 tool was used to determine the quality of the selected studies. Pooled estimates of sensitivity and specificity were calculated. A total of 58 studies comprising 9,997 patients were included. Most studies had a low risk of bias. The sensitivity and specificity for nodal staging of gastric cancer were 49% (95% CI, 37-61%) and 92% (95% CI, 86-96%) for 18F-FDG PET/CT, respectively, and 67% (95% CI, 57-76%) and 86% (95% CI, 81-89%) for CECT, respectively. For metastasis staging, the sensitivity and specificity were 56% (95% CI, 40-71%) and 97% (95% CI, 87-99%) for 18F-FDG PET/CT, respectively, and 59% (95% CI, 41-75%) and 96% (95% CI, 83-99%) for CECT, respectively. For diagnosing cancer recurrence, the pooled sensitivity and specificity were 81% (95% CI, 72-88%) and 83% (95% CI, 74-89%) for 18F-FDG PET/CT, respectively, and 59% (95% CI, 41-75%) and 96% (95% CI, 83-99%) for CECT, respectively. Both 18F-FDG PET/CT and CECT were deemed highly useful for diagnosing recurrent gastric cancer due to their high sensitivities and specificities. However, these techniques cannot be used to exclude or confirm the presence of lymph node metastases or recurrent gastric cancer tumors, but can be used for the confirmation of distal metastasis.

Risk factors analysis and stratification for microscopically positive resection margin in gastric cancer patients

Background

Cancer cells are often found postoperatively at surgical resection margins (RM) in patients with gastric cancer because of submucosal infiltration or hesitation to secure adequate RM. This study was designed to evaluate risk factors for microscopic positive RM and to clarify which patients should undergo intraoperative frozen section diagnosis (IFSD).

Methods

Patients who underwent R0/1 gastrectomy for gastric adenocarcinoma between 2000 and 2018 in a single cancer center in Japan were studied. We divided the patients into a positive RM group and negative RM group according to the results of definitive histopathological examinations. We performed multivariate analysis to analyze risk factors for positive RM by and used the identified risk factors to risk stratify the patients.

Results

A total of 2757 patients were studied, including 49 (1.8%) in the positive RM group. The risk factors significantly associated with positive RM were remnant gastric cancer (odds ratio [OR] 4.7), esophageal invasion (OR 6.3), tumor size ≥80 mm (OR 3.9), and a histopathological diagnosis of undifferentiated type (OR 3.6), macroscopic type 4 (OR 3.7), or pT4 disease (OR 4.6). On risk stratification analysis, the incidence of positive RM was 0.1% without any risk factors, increasing to 0.4% with one risk factor, 3.1% with two risk factors, 5.3% with three risk factors, 21.3% with four risk factors, and 85.7% with five risk factors.

Conclusions

The risk of macroscopically positive RM increased in patients who have risk factors. IFSD should be performed in patients who have four or more risk factors.

Prognostic significance of systemic inflammatory markers in esophageal cancer: Systematic review and meta-analysis

AIM

Impact of several immune-inflammatory markers on long-term outcome has been reported in various malignancies. The aim of the present study was to evaluate through a meta-analysis the oncological outcome of immune-inflammatory markers, such as neutrophil to lymphocyte ratio (NLR), platelet to lymphocyte ratio (PLR), and C-reactive protein to albumin ratio (CAR) in esophageal cancer.

METHODS

A systematic electronic search for relevant studies was carried out in PubMed, Cochrane library, Embase, and Google scholar. Meta-analysis was done using hazard ratio (HR) and 95% confidence interval (CI) as effect measures. A systematic review and meta-analysis were undertaken according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. P-values <.01 were considered statistically significant.

RESULTS

A total of 10 retrospective articles (n = 4551) were included in this study. Synthesized results showed that higher NLR and CAR were significantly associated with poor overall survival (HR 1.47, 95% CI = 1.32-1.63, P < .00001) and HR 1.88, 95% CI = 1.28-2.77, P < .001, respectively). On the contrary, PLR was not a prognostic factor in our analysis (HR 1.25, 95% CI = 1.01-1.54, P < .01). Elevated NLR, PLR, and CAR were strongly associated with a higher T stage (HR 2.28, 95% CI = 1.67-3.11; HR 1.57, 95% CI = 1.29-1.90; HR 1.76, 95% CI = 1.16-2.67, respectively). Begg's funnel plots identified significant publication bias in NLR, but not in PLR and CAR.

CONCLUSION

NLR and CAR represent useful guides for the management of esophageal cancer, although publication bias should be considered. Further prospective studies are needed to confirm the results of the present study.

Long-term outcome following sentinel node navigation surgery for cT1 gastric cancer

Sentinel node navigation surgery (SNNS) has become a standard procedure for early-stage melanoma and breast cancer. However, very few studies have evaluated the long-term clinical outcomes following SNNS for gastric cancer. The present study analyzed 51 patients with cT1 gastric cancer who underwent SNNS at our hospital. Sentinel nodes (SNs) were identified using the dual tracer method. Patients underwent limited gastrectomy with SN station dissection when the SNs were reported as pathologically negative during surgery. When SNs were pathologically positive, standard gastrectomy with D2 lymphadenectomy was performed. Out of the 51 cases, 42 cases (82%) were pathologically diagnosed as SN-negative using a frozen section. The surgical procedures included segmental gastrectomy (n=33) and local resection (n=9). A total of 9 patients (18%) had lymph node metastasis in SNs. The mean observation period was 3,125±167 days, and the 5-year overall survival rate was 98%. There was no recurrence, and body weight loss was minimal following the SNNS. Remnant gastric cancer developed in 4 (8%) of the 50 patients except total gastrectomy. Thus, SNNS was a useful procedure for cT1 gastric cancer from the long-term clinical outcomes, though metachronous gastric cancer should paid further attention to.

Diagnostic accuracy of T stage of gastric cancer from the view point of application of laparoscopic proximal gastrectomy

The preoperative diagnosis of T stage is important in selecting limited treatments, such as laparoscopic proximal gastrectomy (LPG), which lacks the ability to palpate the tumor. Therefore, the present study examined the accuracy of preoperative diagnosis of the depth of tumor invasion in early gastric cancer from the view point of the indication for LPG. A total of 193 patients with cT1 gastric cancer underwent LPG with gastrointestinal endoscopic examinations and a series of upper gastrointestinal radiographs. The patients with pT1 were classified into the correctly diagnosed group (163 patients, 84.5%), and those with pT2 or deeper were classified into the underestimated group (30 patients, 15.5%). Factors that were associated with underestimation of tumor depth were analyzed. Tumor size in the underestimated group was significantly larger; the lesions were more frequently located in the upper third of the stomach and were more histologically diffuse, scirrhous, with infiltrative growth, and more frequent lymphatic and venous invasion. For upper third lesions, in univariate analysis, histology (diffuse type) was associated with underestimation of tumor depth. Multivariate analysis found that tumor size (≥20 mm) and histology (diffuse type) were independently associated with underestimation of tumor depth. gastric cancer in the upper third of the stomach with diffuse type histology and >20 mm needs particular attention when considering the application of LPG.

Usefulness of esophagogastroduodenoscopy and 18F-fluorodeoxyglucose positron-emission tomography in detecting synchronous multiple primary cancers with oral cancer

PURPOSE

The purpose of this study is to compare the value of screening for synchronous multiple primary cancers in other organs by esophagogastroduodenoscopy (EGD) or ¹⁸F-fluorodeoxyglucose positron-emission tomography (PET-CT) in patients newly diagnosed with oral cancer.

METHODS

We retrospectively examined consecutive Japanese patients who were diagnosed with oral squamous cell carcinoma (OSCC) and were screened for synchronous multiple primary cancers in other organs by EGD and/or PET-CT between January 2010 and December 2015 at our institution. The study included 190 patients (106 males and 84 females) from 36 to 93 years of age (median age 68.8 years). The patients were screened by EGD, PET-CT, or both before beginning treatment for OSCC.

RESULTS

Of 190 Japanese patients with OSCC, 15 had multiple primary cancers: 13 patients had double cancer and two had triple cancers. The sites of the 17 multiple primary cancers were gastric (6), esophageal (4), and lung (3), and ovarian, colon, liver, and thyroid (1 each). All of the gastric and esophageal cancers were found by EGD and were not detected by PET-CT. For three patients, the detection of multiple cancers affected the treatment modality or order of treatment selected for the OSCC. In two cases, the oral cancer and multiple primary cancer(s) in another organ were resected simultaneously by joint surgical teams.

CONCLUSIONS

PET-CT for oral cancer patients is an effective supporting diagnostic tool. However, the ability of PET-CT has some limitations. Especially for early detection of the upper gastrointestinal cancers, it is necessary to be supplemented by EGD.

Clinical significance of circulating tumor cells in blood from patients with gastric cancer

Circulating tumor cells (CTC) have been focused on as a target for detecting occult tumors, predicting therapeutic responses and prognoses, and monitoring postoperative recurrence in the clinical management of patients with various malignancies, including gastric cancer. Recent advances in molecular diagnostic tools have contributed to high sensitivity and specificity for the detection of CTC. A conspicuous disparity exists in the incidence of CTC among studies. However, a close relationship has been reported between positivity for CTC and well‐known prognostic clinicopathological factors including depth of tumor invasion, lymph node metastasis, stage, and lymphatic and venous invasion in patients with gastric cancer. According to most studies published on the clinical impact of CTC, the presence of CTC negatively affects the prognosis of patients with gastric cancer. Moreover, the study of CTC based on a meta‐analysis demonstrated their importance as a poor prognostic indicator. In clinical management, pre‐ and post‐therapeutic monitoring of CTC using liquid biopsy may be useful for early detection of subclinical patients or disease recurrence, prediction of tumor progression, and administrative control of adjuvant chemotherapy. Although their functional properties remain unclear, molecular profiling of CTC may contribute to the development of personalized treatment that effectively inhibits tumor progression in patients with advanced gastric cancer. We herein review the clinical significance of CTC as a promising blood marker and therapeutic target in patients with gastric cancer.

Is It Reasonable to Treat Early Gastric Cancer with Mucosal Infiltration and Well Differentiation by Endoscopic Submucosal Resection?

BACKGROUND

While limited endoscopic submucosal dissection (ESD) is increasingly applied in the treatment of early gastric cancer, preoperative prediction of lymph node metastasis is very critical for determining treatment strategies preoperatively. Thus, the aim of this study was to accurately assess the prevalence and pattern of lymph node metastasis in early gastric cancer patients and to identify the best candidates for ESD.

METHODS

From September 2008 to December 2013, a total of 539 patients with early gastric cancer were retrospectively analyzed in the present study. Of them, 503 patients underwent radical gastrectomy and 36 patients underwent ESD. The clinicopathological features were collected and correlations with lymph node metastasis were analyzed. The survival rates of patients were also analyzed.

RESULTS

Lymph node metastasis was observed in 80 of 503 patients (15.9 %). Among these, the rate for mucosal cancer was 8.3 %, and 20.1 % for submucosal cancer. By univariate analysis, risk factors for lymph node metastasis were growth pattern, tumor size, pathological type, depth of invasion, lymphatic-vascular invasion, and neural invasion. By multivariate analysis, risk factors for lymph node metastasis were tumor size, pathological type, depth of invasion, and lymphatic-vascular invasion. The incidence of lymph node metastasis was 0 % in the well-differentiated mucosal cancers, irrespective of tumor size. For the well-differentiated mucosal cancers, the overall survival rates were comparable between patients underwent gastrectomy with lymph node dissection and patients underwent ESD (100 vs 100 %).

CONCLUSIONS

The most important factors for predicting lymph node metastasis in early gastric cancer are tumor size, pathological type, depth of invasion, and lymphatic-vascular invasion. Well-differentiated mucosal gastric cancers could be candidates for ESD.

The Role of 18F-FDG PET/CT in the Primary Staging of Gastric Cancer

Objective: The aim of this study is to explore the role of 18F-FDG PET/CT in the primary staging of gastric cancer in the comparison of ceCT as routine staging method and evaluate influencing parameters of 18F-FDG uptake.

Methods: Thirty-one patients (mean age: 58.9±12.6) who underwent 18F-FDG PET/CT for primary staging of gastric cancer between June 2011 and June 2012 were included to the study. 18F-FDG PET/CT findings were compared with pathological reports in patients who underwent surgery following PET/CT. 18F-FDG PET/CT findings of primary lesions, lymph nodes and adjacent organs were compared with ceCT findings and pathological reports. Since 6 patients were accepted as inoperable according to 18F-FDG PET/CT and/or ceCT and/or laparotomy and/or laparoscopy findings, pathological confirmation could not be possible.

Results: In the postoperative TNM staging of patients, while 1 (4%), 1 (4%), 4 (16%), 2 (8%), 12 (48%) and 5 (20%) patients were staged as T0, Tis, T1, T2, T3 and T4, respectively, 8 (32%), 6 (24%), 6 (24%) and 5 (20%) patients were N0, N1, N2 and N3 respectively. 18F-FDG PET/CT was totally normal in 2 patients. While primary tumors were FDG avid in 27 patients, in 17 and 6 patients FDG uptake was observed in perigastric lymph nodes and distant organs, respectively. Mean SUVmax of FDG avid tumors was calculated as 13.49±9.29 (3.00-44.60). However, SUVmax of lymph nodes was computed as 9.28±6.92 (2.80-29.10). According to sub-analysis of histopathological subtypes of primary tumors, SUVmax of adenocarsinomas was calculated as 15.16 (3.00-44.60), of signet ring cells as 9.90 (5.50-17.70), of adenocarcinomas with signet ring cell component as 11.27 (6.20-13.90) (p=0.721). In the comparison with histopathological examination while ceCT was TP, TN, FN in 23, 1 and 1 patients, 18F-FDG PET/CT was TP, FP, FN in 20, 1 and 4 patients, respectively. Sensitivity, specificity, accuracy, PPD and NPV of ceCT in the detection of lymph node metastasis was calculated as 83.3%, 75%, 80%, 87.5% and 66.6%, respectively. These parameters for 18F-FDG PET/CT were 64.7%, 100%, 76%, 100% and 57.1%.

Conclusion: Despite lower sensitivity than ceCT, diagnostic power of 18F-FDG PET/CT in the preoperative staging of gastric cancer is acceptable. Because of its high PPV, it might be beneficial in the evaluation of patients with suspected lymph nodes. The role of 18F-FDG PET/CT seems to be limited in the early stage and signet ring cell carcinomas due to lower 18F-FDG uptake.

Long-term quality-of-life comparison of total gastrectomy and proximal gastrectomy by postgastrectomy syndrome assessment scale (PGSAS-45): a nationwide multi-institutional study

BACKGROUND

Although proximal gastrectomy (PG) is widely accepted as a function-preserving operation for early upper-third gastric cancer, postoperative disorders, such as reflux or gastric stasis, have often been pointed out. From the perspective of postoperative disorder, the choice of total gastrectomy (TG) or PG for such cancers is still controversial. By using the newly developed Postgastrectomy Syndrome Assessment Scale (PGSAS)-45, the quality of life after TG and PG was compared.

METHODS

The PGSAS-45 consists of 45 items composed of the SF-8 and GSRS scales and 22 new items. The main outcomes are measured by seven subscales (SS) covering symptoms, physical and mental component summary (SF-8), meals (amount and quality), ability to work, dissatisfaction for daily life, and change in body weight. A total of 2,368 eligible questionnaires were acquired from 52 institutions. From these, 393 patients with TG and 193 patients with PG were selected and compared.

RESULTS

The PG was better than TG in terms of body weight loss (TG 13.8% vs. PG 10.9%; p = 0.003), necessity for additional meals (2.4 vs. 2.0; p < 0.001), diarrhea SS (2.3 vs. 2.0; p = 0.048), and dumping SS (2.3 vs. 2.0; p = 0.043). There were no differences in the other main outcome measures.

CONCLUSIONS

Proximal gastrectomy appears to be valuable as a function-preserving procedure for early upper-third gastric cancer.

Photodynamic therapy using nanoparticle loaded with indocyanine green for experimental peritoneal dissemination of gastric cancer

Although there have been multiple advances in the development of novel anticancer agents and operative procedures, prognosis of patients with advanced gastric cancer remains poor, especially in patients with peritoneal metastasis. In this study, we established nanoparticles loaded with indocyanine green (ICG) derivatives: ICG loaded lactosomes (ICGm) and investigated the diagnostic and therapeutic value of photodynamic therapy (PDT) using ICGm for experimental peritoneal dissemination of gastric cancer. Experimental peritoneal disseminated xenografts of human gastric cancer were established in nude mice. Three weeks after intraperitoneal injection of the cancer cells, either ICGm (ICGm-treated mice) or ICG solution (ICG-treated mice) was injected through the tail vein. Forty-eight hours after injection of the photosensitizer, in vivo and ex vivo imaging was carried out. For PDT, 48 h after injection of the photosensitizer, other mice were irradiated through the abdominal wall, and the body weight and survival rate were monitored. In vivo imaging revealed that peritoneal tumors were visualized through the abdominal wall in ICGm-treated mice, whereas only non-specific fluorescence was observed in ICG-treated mice. The PDT reduced the total weight of the disseminated nodules and significantly improved weight loss and survival rate in ICGm-treated mice. In conclusion, ICGm can be used as a novel diagnostic and therapeutic nanodevice in peritoneal dissemination of gastric cancer.

Feasibility of sentinel node navigation surgery after noncurative endoscopic resection for early gastric cancer

BACKGROUND AND AIM

Recently, the use of additional surgery after noncurative endoscopic resection has gradually increased due to the rapid spread of endoscopic treatments in selected patients with early gastric cancer. Sentinel node navigation surgery (SNNS) has also been recognized as a minimally invasive surgery with personalized lymphadenectomy in early gastric cancer. Here, we assessed the feasibility of SNNS after noncurative endoscopic resection for early gastric cancer.

METHODS

Sixteen patients with early gastric cancer, in whom additional surgery had been indicated due to noncurative endoscopic resection, were enrolled. They underwent a gastrectomy with standard lymphadenectomy. One day before surgery, (99m) technetium-tin colloid was endoscopically injected into the submucosa around the tumor. After surgery, the uptake of radioisotope in dissected lymph nodes was measured using Navigator GPS. Then, all dissected lymph nodes were investigated by hematoxylin-eosin staining and immunohistochemistry using an antihuman cytokeratin monoclonal antibody.

RESULTS

Hematoxylin-eosin staining demonstrated lymph node metastasis in two (12.5%) of 16 patients and in three (0.8%) of 382 nodes. However, immunohistochemistry showed that none of the patients had lymph node micrometastasis. Sentinel nodes (SNs) were identified in all patients. The mean number of SNs was 3.1 (range, 1-6). Among two patients with lymph node metastasis, the SNs, at least, contained positive nodes. Accordingly, the false-negative and accuracy rates were 0% and 100%, respectively.

CONCLUSION

Our results indicate that SNNS may have potential as a further minimally invasive surgery in early gastric cancer patients after noncurative endoscopic resection.

Risk of limited lymph node dissection in patients with clinically early gastric cancer: indications of extended lymph node dissection for early gastric cancer

BACKGROUND

Laparoscopic gastrectomy is usually indicated in T1 N0-1 early gastric cancer (EGC). Limited lymph node dissection, such as D1+, is applied in these cases. However, preoperative staging is not always correct, and the risk of undertreatment thus exists.

METHODS

Patients with clinically early gastric cancer (cEGC) who underwent gastrectomy with lymph node dissection of D2 and over were selected from 4,021 patients with gastric cancer. The station numbers of all metastatic lymph nodes (MLNs) were identified, and MLNs were classified into groups 1 and 2 (including lymph nodes of second tier and over) on the basis of the system of the Japanese Gastric Cancer Association, irrespective of the number of MLNs. Clinicopathological data were compared according to the existence of lymph node metastasis and the classification of MLNs.

RESULTS

Of 1,308 patients with cEGC who fulfilled the inclusion criteria, 1,184 (90.5 %) were diagnosed pathologically with EGC. Among 126 patients with cEGC who were diagnosed with lymph node metastasis, 93 patients had only group 1 MLNs and 33 patients had group 2 MLNs. Tumor location in the proximal third of the stomach (odds ratio 5.450) and ulceration (odds ratio 11.928) were significant factors for group 2 metastasis.

CONCLUSIONS

Extended lymph node dissection is recommended in cEGC with ulceration or disease located in the proximal third of the stomach.

FDG PET/CT diagnosis of clinically occult gastric cancer

AIM: To investigate the use of fluorodeoxyglucose (FDG) positron emission tomography ( PET)/CT imaging in diagnosis of clinically occult gastric cancer.

METHODS: The imaging data for 26 patients with clinically occult gastric cancer who underwent FDG PET/CT imaging were reviewed retrospectively. They were hospitalized for metastatic tumors and therefore underwent FDG PET/CT for detecting carcinoma of unknown primary origin. They were finally diagnosed with gastric cancer by endoscopy (n = 24) or laparoscopy (n = 2). Based on imaging manifestations, the patients were divided into three groups: easily diagnosed, suspected, and hardly diagnosed.

RESULTS: PET imaging showed 57.7% (15/26) of intensively positive cases, 23.1% (6/26) of positive cases, and 19.2% (5/26) of negative cases. CT imaging showed 76.9% (20/26) of intensively positive cases, 11.5% (3/26) of positive cases, and 11.5% (3/26) of negative cases. The percentages of easily diagnosed, suspected, and hardly diagnosed patients were 53.8% (14/26), 34.6% (9/26) and 11.5% (3/26), respectively.

CONCLUSION: FDG PET/CT imaging can help diagnose clinically occult gastric cancer in about 88.4% of patients.

Minor gastric resections with modified lymphadenectomy in early gastric cancer with negative sentinel node

OBJECTIVE

To study the sentinel lymph node in early gastric cancer as a diagnostic method of unsuspected lymph node metastasis, which may allow the performance, in those with negative lymph nodes, of smaller gastric resections with limited lymphadenectomy.

METHODS

We studied seven patients with early gastric cancer treated at the Hospital Universitário Clementino Fraga Filho, Federal University of Rio de Janeiro, from September 2008 to May 2011, who underwent sentinel lymph node exams, performed by intraoperative peritumoral endoscopic injection of patent blue dye.

RESULTS

We found an average of three sentinel nodes per patient. The frozen biopsy of lymph nodes was negative for metastases, which allowed the realization of atypical gastric resection in three cases and antrectomy with BI reconstruction in four. The performed lymphadenectomy was modified D1. There was no operative mortality. The duration of postoperative follow-up ranged from five to 37 months, without evidence of recurrence. One patient developed a second early tumor 13 months after the initial surgery and underwent total gastrectomy.

CONCLUSION

The sentinel lymph node in early gastric cancer proved to be an effective method for the evaluation of nodal metastases in seven patients and allowed for smaller gastric resections and limited lymphadenectomies. These minor procedures reduce the risk of postoperative complications, maintaining, on the other hand, the oncological radicality that is required in the treatment of gastric cancer.

Laparoscopic gastrectomy after incomplete endoscopic resection for early gastric cancer

Endoscopic submucosal dissection (ESD) utilizes electrical coagulation, which can cause burns, fibrosis and adhesion of the stomach and surrounding tissue; these complications might increase the surgical difficulties for subsequent laparoscopy-assisted gastrectomy (LAG) and the risk of complications. However, scarce data are available on the influence of previous ESD on LAG. The purpose of this study was to evaluate the feasibility and safety of LAG following incomplete ESD in patients with early gastric cancer. Ninety-seven patients who underwent LAG were analyzed retrospectively; 17 patients had undergone ESD previously and the remaining 80 patients had no history of ESD. Clinicopathological data and surgical outcomes were compared between the two groups. No differences were observed in surgical outcomes of LAG after ESD in terms of operation time, intraoperative blood loss, total number of harvested lymph nodes, time until start of flatus, and postoperative hospital stay. These results were not influenced by tumor location and operative procedures. In conclusion, in terms of surgical outcomes, LAG is a safe and feasible procedure for the treatment of early gastric cancer regardless of previous endoscopic treatment. LAG may be the first-choice radical treatment after incomplete ESD for early gastric cancer.

The role of CT and staging laparoscopy in the staging of gastric cancer

AIM

To assess the relative roles of computed tomography (CT) and diagnostic laparoscopy in the staging process of patients with potentially curable gastric cancer.

MATERIALS AND METHODS

Fifty-two patients underwent laparoscopy and CT as part of staging; 36 patients underwent surgery without laparoscopy. Pathological findings at laparoscopy or surgery were compared with initial CT reports, and analysis of the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) was performed.

RESULTS

Of the patients who underwent laparoscopy and CT, six were staged as positive for peritoneal disease (PD), of which five (83%) were positive for PD at laparoscopy. Forty-six patients were reported at CT as negative for PD, of which 40 (87%) were negative at laparoscopy. Of 36 patients with no advanced disease at CT, who had surgery without diagnostic laparoscopy, nine (25%) were positive at surgery for PD. The overall sensitivity of CT for PD was therefore 25%, the specificity was 99%, the PPV was 86%, and the NPV was 83%.

CONCLUSION

CT is not sufficiently sensitive to detect or exclude PD in patients with gastric cancer, although is highly specific. Staging laparoscopy is an essential adjunct to imaging in all patients being considered for curative surgery for gastric cancer.

Predictive value of the pathological extent of tumor invasion in endoscopic resection margins positive for residual tumor cells in surgically resected specimens of early gastric cancer

Although endoscopic resection (ER) is considered to be the optimal treatment for early gastric cancer, indications for radical gastrectomy in patients undergoing incomplete ER for early gastric cancer remain unclear. We evaluated the pathological extent of tumor invasion in the ER margins positive for residual tumor cells in the surgically resected specimens. We measured the vertical and/or horizontal length of the exposed tumor in the ER specimens of 23 patients with margins positive for tumor cells. We compared the clinicopathological data to distinguish between the presence and absence of residual tumor cells in the surgically resected specimens. Of 17 lesions with exposed tumor cells in the vertical margins of the ER specimens, only 3 (17.6%) had residual tumor cells in the corresponding site of the surgically resected specimens. By contrast, of 10 lesions with exposed tumor cells in the horizontal margins of the ER specimens, 8 (80.0%) had residual tumor cells in the corresponding site of the surgically resected specimens. The length of the exposed tumor in the vertical margins of the ER specimens was significantly associated with the incidence of residual tumor cells in the vertical margins of the surgically resected specimens. When the cut-off value for the length of the exposed tumor in the vertical ER margins was set to >3 mm, the sensitivity and specificity were 0.67 and 0.95, respectively. In conclusion, measurement of the length of the exposed tumor in the ER margins for early gastric cancer is a simple procedure that is able to determine whether additional surgical intervention is necessary.

Endoscopy and role of endoscopic resection in gastric cancer

Patient selection for endoscopic resection is based on meticulous endoscopic examination and histological assessment so as to avoid performing this procedure on patients with a high risk of lymph node involvement or metastatic disease. Currently, endoscopic mucosal resection (EMR) is used for tumors <2 cm, and endoscopic submucosal dissection (ESD) should be considered for tumors >2 cm. The advantage of ESD is that it achieves en-bloc resection of larger tumors, potentially reducing the risk of disease recurrence.

Quality of life after laparoscopy-assisted pylorus-preserving gastrectomy: an evaluation using a questionnaire mailed to the patients

PURPOSE

This study investigated the postoperative quality of life (QOL) after laparoscopy-assisted pylorus-preserving gastrectomy (LAPPG) in comparison to laparoscopy-assisted distal gastrectomy (LADG).

METHODS

Twenty-one patients with early-stage gastric cancer underwent minimally invasive LADG (n = 12) or LAPPG (n = 9). Demographic and cancer-related data were obtained retrospectively from medical records. QOL was assessed using a 13-item questionnaire and the Japanese edition of the Gastrointestinal Symptom Rating Scale, which were mailed to patients twice postoperatively. Body weight and hemoglobin levels were measured at the same time.

RESULTS

Early upper abdominal pain was rated as significantly worse with LAPPG than with LADG at the first checkup (1.4 vs. 1.0, P = 0.02) but not at the second checkup (1.3 vs. 1.0, P = 0.07). There was a trend toward less body weight loss in the LAPPG patients in comparison to the LADG patients. The serum hemoglobin levels of LAPPG patients at the second checkup showed significantly higher than LADG patients (13.3 vs. 11.6 g/dL, P < 0.05).

CONCLUSIONS

LAPPG and LADG produce similar QOL in patients. Trends toward less body weight loss and improved anemia in LAPPG patients may therefore become more pronounced in future studies that have adequate number of the patients and longer follow-up periods.

Outcome of overlap anastomosis using a linear stapler after laparoscopic total and proximal gastrectomy

BACKGROUND

Recently, novel intracorporeal esophagojejunostomy using a linear stapler after laparoscopic total gastrectomy (LTG) was reported and termed as the overlap method. In this study, we evaluated the feasibility and safety of the overlap method for esophagojejunostomy or esophagogastrostomy after LTG or laparoscopic proximal gastrectomy (LPG), respectively.

METHODS

Twenty-five patients underwent anastomosis using a linear stapler during esophagojejunostomy and esophagogastrostomy after LTG and LPG, respectively. Clinicopathological data and surgical outcomes were evaluated.

RESULTS

The average surgical duration for LTG was 236.8 min compared with 224.1 min for LPG. Postoperative complications were observed in four patients (16.0%); these included a wound infection, an intestinal obstruction, an afferent loop syndrome, and a reflux symptom. The average postoperative hospital stay of the patients was 12.5 days. There was no case of conversion to open surgery, anastomotic leakage or stenosis, or mortality.

CONCLUSIONS

The overlap method for esophagojejunostomy or esophagogastrostomy after LTG or LPG is safe and feasible and does not require an additional minilaparotomy, which may result in less pain and favorable cosmetic outcomes.

Japanese Gastric Cancer Association Task Force for Research Promotion: clinical utility of ¹⁸F-fluoro-2-deoxyglucose positron emission tomography in gastric cancer. A systematic review of the literature

Since April 2010, the Japanese Public Health Insurance System has covered the costs incurred for performing ¹⁸F-fluoro-2-deoxyglucose positron emission tomography (FDG-PET) imaging for patients with advanced gastric cancer. The aim of this review was to evaluate the clinical impact of PET for patients with gastric cancer. A systematic literature search was performed in PubMed/MEDLINE using the keywords "gastric cancer" and "PET" to search for relevant articles published from January 2000 to September 2010. The clinical impact of selected articles was assessed by the authors to evaluate the following: (a) tumor staging, (b) diagnosis for recurrent disease, (c) evaluation of treatment response, and (d) screening for gastric cancer. FDG uptake increases in papillary adenocarcinoma, tubular adenocarcinoma, and solid-type poorly differentiated adenocarcinoma. This uptake is also associated with glucose transporter 1 expression. The sensitivity and specificity of FDG-PET for metastatic lymph node detection were 21-40% and 89-100%, respectively. The sensitivity and specificity for distant metastasis detection were 35-74% and 74-99%, respectively. Treatment response can be detectable at an earlier stage by PET than by computed tomography (CT), because FDG uptake by cancer cells decreases according to the treatment response. In summary, although PET has limitations such as frequent false-negative cases in signet-ring cell carcinoma and non-solid type poorly differentiated carcinoma, it can contribute to the selection of a more appropriate treatment modality by detecting distant metastases and treatment response.