Pre-operative TN staging of gastric cancer using a 15 MHz ultrasound miniprobe

Diagnostic accuracy of endoscopic ultrasonography (EUS) for the preoperative locoregional staging of primary gastric cancer

BACKGROUND

Endoscopic ultrasound (EUS) is proposed as an accurate diagnostic device for the locoregional staging of gastric cancer, which is crucial to developing a correct therapeutic strategy and ultimately to providing patients with the best chance of cure. However, despite a number of studies addressing this issue, there is no consensus on the role of EUS in routine clinical practice.

OBJECTIVES

To provide both a comprehensive overview and a quantitative analysis of the published data regarding the ability of EUS to preoperatively define the locoregional disease spread (i.e., primary tumor depth (T-stage) and regional lymph node status (N-stage)) in people with primary gastric carcinoma.

SEARCH METHODS

We performed a systematic search to identify articles that examined the diagnostic accuracy of EUS (the index test) in the evaluation of primary gastric cancer depth of invasion (T-stage, according to the AJCC/UICC TNM staging system categories T1, T2, T3 and T4) and regional lymph node status (N-stage, disease-free (N0) versus metastatic (N+)) using histopathology as the reference standard. To this end, we searched the following databases: the Cochrane Library (the Cochrane Central Register of Controlled Trials (CENTRAL)), MEDLINE, EMBASE, NIHR Prospero Register, MEDION, Aggressive Research Intelligence Facility (ARIF), ClinicalTrials.gov, Current Controlled Trials MetaRegister, and World Health Organization International Clinical Trials Registry Platform (WHO ICTRP), from 1988 to January 2015.

SELECTION CRITERIA

We included studies that met the following main inclusion criteria: 1) a minimum sample size of 10 patients with histologically-proven primary carcinoma of the stomach (target condition); 2) comparison of EUS (index test) with pathology evaluation (reference standard) in terms of primary tumor (T-stage) and regional lymph nodes (N-stage). We excluded reports with possible overlap with the selected studies.

DATA COLLECTION AND ANALYSIS

For each study, two review authors extracted a standard set of data, using a dedicated data extraction form. We assessed data quality using a standard procedure according to the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) criteria. We performed diagnostic accuracy meta-analysis using the hierarchical bivariate method.

MAIN RESULTS

We identified 66 articles (published between 1988 and 2012) that were eligible according to the inclusion criteria. We collected the data on 7747 patients with gastric cancer who were staged with EUS. Overall the quality of the included studies was good: in particular, only five studies presented a high risk of index test interpretation bias and two studies presented a high risk of selection bias.For primary tumor (T) stage, results were stratified according to the depth of invasion of the gastric wall. The meta-analysis of 50 studies (n = 4397) showed that the summary sensitivity and specificity of EUS in discriminating T1 to T2 (superficial) versus T3 to T4 (advanced) gastric carcinomas were 0.86 (95% confidence interval (CI) 0.81 to 0.90) and 0.90 (95% CI 0.87 to 0.93) respectively. For the diagnostic capacity of EUS to distinguish T1 (early gastric cancer, EGC) versus T2 (muscle-infiltrating) tumors, the meta-analysis of 46 studies (n = 2742) showed that the summary sensitivity and specificity were 0.85 (95% CI 0.78 to 0.91) and 0.90 (95% CI 0.85 to 0.93) respectively. When we addressed the capacity of EUS to distinguish between T1a (mucosal) versus T1b (submucosal) cancers the meta-analysis of 20 studies (n = 3321) showed that the summary sensitivity and specificity were 0.87 (95% CI 0.81 to 0.92) and 0.75 (95% CI 0.62 to 0.84) respectively. Finally, for the metastatic involvement of lymph nodes (N-stage), the meta-analysis of 44 studies (n = 3573) showed that the summary sensitivity and specificity were 0.83 (95% CI 0.79 to 0.87) and 0.67 (95% CI 0.61 to 0.72), respectively.Overall, as demonstrated also by the Bayesian nomograms, which enable readers to calculate post-test probabilities for any target condition prevalence, the EUS accuracy can be considered clinically useful to guide physicians in the locoregional staging of people with gastric cancer. However, it should be noted that between-study heterogeneity was not negligible: unfortunately, we could not identify any consistent source of the observed heterogeneity. Therefore, all accuracy measures reported in the present work and summarizing the available evidence should be interpreted cautiously. Moreover, we must emphasize that the analysis of positive and negative likelihood values revealed that EUS diagnostic performance cannot be considered optimal either for disease confirmation or for exclusion, especially for the ability of EUS to distinguish T1a (mucosal) versus T1b (submucosal) cancers and positive versus negative lymph node status.

AUTHORS' CONCLUSIONS

By analyzing the data from the largest series ever considered, we found that the diagnostic accuracy of EUS might be considered clinically useful to guide physicians in the locoregional staging of people with gastric carcinoma. However, the heterogeneity of the results warrants special caution, as well as further investigation for the identification of factors influencing the outcome of this diagnostic tool. Moreover, physicians should be warned that EUS performance is lower in diagnosing superficial tumors (T1a versus T1b) and lymph node status (positive versus negative). Overall, we observed large heterogeneity and its source needs to be understood before any definitive conclusion can be drawn about the use of EUS can be proposed in routine clinical settings.

Low accuracy of endoscopic ultrasonography for detailed T staging in gastric cancer

Background

The accuracy of endoscopic ultrasonography (EUS) for preoperative staging of gastric cancer varies. The aim of this study was to investigate the accuracy of EUS tumor (T) and node (N) staging, and to identify the histopathological factors influencing accuracy based on the detailed tumor depth of gastric cancer.

Methods

In total, 309 patients with gastric cancer with confirmed pathological staging underwent EUS examination for preoperative staging at Seoul St. Mary’s Hospital, Korea, between January and December 2009. The T and N staging of EUS and the pathologic report were compared.

Results

The overall accuracies of EUS for T stage and the detailed T stages were 70.2% and 43.0%, respectively. In detailed stage, tumors greater than 50 mm in diameter were significantly associated with T overstaging (odds ratio (OR) = 2.094). The overall accuracy of EUS for N staging was 71.2%. Tumor size (20 mm ≤ size < 50 mm, OR = 4.389; and 50 mm ≤ size, OR = 8.170), cross-sectional tumor location (circumferential, OR = 4.381) and tumor depth (submucosa, OR = 3.324; muscular propria, OR = 6.923; sub-serosa, OR = 4.517; and serosa-exposed, OR = 6.495) were significant factors affecting incorrect nodal detection.

Conclusions

Careful attention is required during EUS examination of large-sized gastric cancers to increase accuracy, especially for T staging.

Diagnostic accuracy of T and N stages with endoscopy, stomach protocol CT, and endoscopic ultrasonography in early gastric cancer

BACKGROUND

Preoperative accurate diagnosis of the T and N stages in early gastric cancer (EGC) is important in determining the application of various limited treatments. The aim of this study is to analyze the accuracy of T and N staging of EGC with esophagogastroduodenoscopy (EGD), Stomach protocol CT (S-CT), and endoscopic ultrasonography (EUS), and the factors influencing the accuracy.

METHODS

Four hundred and thirty-four patients preoperatively diagnosed as EGC using EGD or S-CT and undergoing curative gastrectomy at Seoul National University Hospital in 2005 were included. The T and N stage reviewed by experienced personnel were compared with the surgical pathology.

RESULTS

The predictive values for EGC of EGD, S-CT, and EUS were 87.4%, 92.2%, and 94.1%, respectively. The predictive values for node negativity of S-CT, and EUS were 90.1% and 92.6%, respectively. The factors leading to underestimation of T stage with EGD were the upper third location, the size greater than 2 cm, and diffuse type of tumor. Those with S-CT were female sex, the upper third location and lesion size greater than 2 cm.

CONCLUSIONS

Before applying limited treatment for EGC, a surgeon should consider the risk factors of underestimation of T stage with EGD or S-CT.

Imaging in local staging of gastric cancer: a systematic review

PURPOSE

Endoscopic ultrasound (EUS) has been established as the diagnostic modality of choice in local (T) staging of gastric cancer. Multidetector row computed tomography (MDCT) and magnetic resonance imaging (MRI) are promising alternatives. The aim of this study was to systematically review the literature regarding the performance of each of these imaging modalities.

METHODS

A systematic search for relevant studies was performed in the PubMed/MEDLINE and EMBASE databases. Two reviewers independently assessed the methodological quality of each study. Local staging performance of included studies was calculated.

RESULTS

Twenty-two EUS studies, five MDCT studies, one combined EUS and MDCT study, and three MRI studies met the inclusion criteria. The studies were of moderate methodological quality. Diagnostic accuracy of overall T staging for EUS, MDCT, and MRI varied between 65% to 92.1%, 77.1% to 88.9%, and 71.4% to 82.6%, respectively. Sensitivity for assessing serosal involvement for EUS, MDCT, and MRI varied between 77.8% to 100%, 82.8% to 100%, and 89.5% to 93.1%, respectively. Specificity for assessing serosal involvement for EUS, MDCT, and MRI varied between 67.9% to 100%, 80% to 96.8%, and 91.4% to 100%, respectively.

CONCLUSION

EUS, MDCT, and MRI achieve similar results in terms of diagnostic accuracy in T staging and in assessing serosal involvement. Most experience has been gained with EUS. Few MDCT studies and even fewer MRI studies are available. Thus, EUS remains the first-choice imaging modality in preoperative T staging of gastric cancer.

Number of lymph node metastases and its prognostic significance in early gastric cancer: a multicenter Italian study

BACKGROUND AND OBJECTIVES

This study was aimed at evaluating the prognostic significance of the number of metastatic nodes in early gastric cancer (EGC).

METHODS

In this multicenter retrospective study 652 cases of resected EGC were analyzed. We searched for lymph node metastases-associated risk factors and to identify subsets of patients with different prognosis according to the number of involved nodes.

RESULTS

Nodal involvement was observed in 14.1%. A significant correlation was found between the presence of node metastases and tumor size (RR 1.34, P = 0.001), submucosal invasion (RR: 3.14, P = 0.007), Lauren diffuse/mixed type (RR: 4.88, P < 0.001) and Kodama Pen A type (RR: 4.59, P < 0.001). The 10-year survival rate was 92% for N0 cases, 82% and 73% for tumors with one to three and four to six positive nodes while it dropped to 27% with more than six metastatic nodes. Interestingly enough, the 10-year risk of recurrence diminished with the increasing number of retrieved nodes (>15) even in N0 patients.

CONCLUSIONS

Nodal involvement confirmed to be a significant prognostic factor. In view of the trend to a lower risk of recurrence when more than 15 nodes were retrieved and the better staging achieved we consider D2 lymphadenectomy the treatment of choice.

Laparoscopy-assisted distal gastrectomy for early gastric cancer: is it beneficial for patients of heavier weight?

OBJECTIVE

In this retrospective review, we evaluated the advantages and disadvantages of LADG for patients of heavier weight with early gastric cancer.

SUMMARY BACKGROUND DATA

LADG has been used to treat early gastric cancer. We and others have reported less operative blood loss, less pain, early recovery of bowel activity, early restart of oral intake, and a shorter hospital stay with LADG compared with a conventional open method. There is, however, little information on the advantages of LADG for obese patients with early gastric cancer.

METHODS

Between January 1996 and March 2002, 76 patients with preoperatively diagnosed early gastric carcinoma underwent LADG in our department. We classified these patients into 2 groups on the basis of body mass index (BMI). Nineteen patients had a high-BMI (>/= 24.2 kg/m2), and 57 patients had a normal-BMI (<24.2 kg/m2). We collected data by retrospectively reviewing the medical charts.

RESULTS

Extension of the minilaparotomic incision or conversion to laparotomy was needed in 6 (32%) of the 19 patients in the high-BMI group, whereas only 3 (5%) of 57 patients in the normal-BMI group required either. In the high-BMI group, Roux-en-Y anastomosis rather than Billroth I anastomosis was adopted more often than in the normal-BMI group, due to the difficulty of the reconstruction (58% versus 4%, P = 0.001). Significantly longer operative time (370 +/- 61 minutes versus 317 +/- 58 minutes, P = 0.015) and prolonged recovery of bowel activity (3.5 +/- 1.0 days versus 2.6 +/- 1.0 days, P = 0.007) were observed in the patients in the high-BMI group.

CONCLUSIONS

In the current study, LADG in patients of heavier weight was accompanied by more technical difficulties, and the disadvantages of longer operative time and delayed recovery of bowel activity was observed in patients of heavier weight. Heavier weight appears to be an ominous factor in the successful completion of LADG and should be considered in the decision to use LADG. There are still benefits of a decreased incidence of serious wound and hernia complications in successful cases.

Curative treatment of gastric cancer: towards a multidisciplinary approach?

Despite marked decreases in incidence over the last century, particularly in developed countries, gastric cancer is still the second-most common tumor worldwide. Surgery remains the gold standard for the cure of locoregional disease. However, in most countries, the diagnosis is made at an advanced stage, and the 5-year survival for surgically resectable disease stays far below 50%. The efficacy of chemotherapy and/or radiation therapy in addition to surgery has been actively studied over the last 30 years. Unfortunately, with few exceptions, most studies of adjuvant therapy in gastric cancer have given deceiving results. The purpose of this review is to address the reasons for our failure to objectivate an improvement in the cure of gastric cancer with adjuvant treatment in most trials, and to consider potential solutions. The low efficacy of chemotherapy regimens available up to now may have hampered our progress. In addition, many previous studies suffered limitations of design or methodology (e.g. low accrual, inadequate disease stage selection, inadequate surgical treatment) that may have obscured a treatment effect. Furthermore, the reduced treatment tolerance of post-gastrectomy patients, perhaps due to their poor nutritional status, results in decreased or delayed adjuvant systemic therapy, with potential adverse consequences in its efficacy. Among potential solutions, the arrival of new drugs, taxanes and topoisomerase I inhibitors in particular, which have shown encouraging results in metastatic disease, may increase the impact of chemotherapy in a multidisciplinary treatment approach. Pre-treatment with chemotherapy and/or radiation therapy prior to surgery may also be advantageous, averting the problems associated with post-surgical treatment. Such an approach has been shown to be feasible in phase II studies, and is relatively well tolerated by patients. Several carefully designed randomized phase III trials are underway to answer this question.

Preoperative TN staging of esophageal cancer: Comparison of miniprobe ultrasonography, spiral CT and MRI

AIM: To evaluate the value of miniprobe sonography (MPS), spiral CT and MR imaging (MRI) in the tumor and regional lymph node staging of esophageal cancer.

METHODS: Eight-six patients (56 men and 30 women; age range of 39-73 years, mean 62 years) with esophageal carcinoma were staged preoperatively with imaging modalities. Of them, 81 (94%) had squamous cell carcinoma, 4 (5%) adenocarcinoma, and 1 (1%) adenoacanthoma. Eleven patients (12%) had malignancy of the upper one third, 41 (48%) of the mid-esophagus and 34 (40%) of the distal one third. Forty-one were examined by spiral CT in whom 13 were co-examined by MPS, and forty-five by MRI in whom 18 were also co-examined by MPS. These imaging results were compared with the findings of the histopathologic examination for resected specimens.

RESULTS: In staging the depth of tumor growth, MPS was significantly more accurate (84%) than spiral CT and MRI (68% and 60%, respectively, P < 0.05). The specificity and sensitivity were 82% and 85% for MPS; 60% and 69% for spiral CT; and 40% and 63% for MRI, respectively. In staging regional lymph nodes, spiral CT was more accurate (78%) than MPS and MRI (71% and 64%, respectively), but the difference was not statistically significant. The specificity and sensitivity were 79% and 77% for spiral CT; 75% and 68% for MPS; and 68% and 62% for MRI, respectively.

CONCLUSION: MPS is superior to spiral CT or MRI for T staging, especially in early esophageal cancer. However, the three modalities have the similar accuracy in N staging. Spiral CT or MRI is helpful for the detection of far-distance metastasis in esophageal cancer.

Analysis of early (pT1) gastric cancer with submucosal invasion: surgical management and possibility to schedule less invasive surgery

BACKGROUND

Early gastric cancer (EGC) is one of the popular targets of less invasive surgery. The aim of the present study is to clarify the possibility of scheduling a less invasive surgery for EGC cases with submucosal (SM) invasion.

METHODS

Eighty cases of EGC with SM invasion were analyzed clinicopathologically and immunohistochemically. Correlations between factors that reflect cancer progression and data from endoscopic examination were investigated.

RESULTS

Thirteen cases (16.3%) showed lymph node metastasis and the numbers of metastasis-positive lymph nodes ranged from 1 to 18. Two cases showed lymph node metastasis not only in the perigastric area, but also along the left gastric artery and the common hepatic artery. Only the tumor size showed a significant correlation with lymph node metastasis (P = .014) using the data from preoperative endoscopic examination. With respect to p53 overexpression, there was no significant correlation with pathologic factors in EGC with SM invasion. The simple protuberance types that were <2 cm in diameter had no lymph node metastasis.

CONCLUSIONS

It seems difficult to predict the progression of EGC with SM invasion from the data currently obtained by preoperative endoscopic examination. It was suggested that less invasive surgery could be scheduled only for simple protuberance type cases that were <2 cm in diameter. Radical gastrectomy and D2 lymph node dissection is required, in open surgery or laparoscopic surgery, for any other type of EGC with SM invasion.

Role of endoscopy in staging colorectal cancer

The treatment of colorectal cancer depends in large measure on the depth of tumor invasion and the extent of lymph node involvement. Endoscopic ultrasonography (EUS) has added a new dimension to the evaluation of tumor invasion and lymph node involvement in gastrointestinal cancer. The overall EUS accuracy for colorectal cancer T-staging is 78%, specificity is 73%, and sensitivity is 94%. In determining the nodal involvement by tumor, EUS has an accuracy of 75%, specificity of 73%, and sensitivity of 74%. Comparison with computerized tomography (CT), magnetic resonance imaging (MRI), and MRI with endorectal coil (MRIEC) shows that EUS is an effective single modality for assessing tumor penetration of the rectal wall. It does not, however, allow the assessment of distant metastatic disease. For assessing lymph node involvement, MRIEC offers the most comprehensive information.

Preoperative staging of rectal cancer using a 7.5 MHz front-loading US probe

BACKGROUND

Conventional echoendoscopes have disadvantages when used for staging colorectal cancer including the inability to pass the instrument through tight stenosis and limited maneuverability. This study evaluated the preoperative use of a newly developed 7.5 MHz front-loading ultrasound probe (FLUP) for local staging of rectal cancer.

METHODS

A 7.5 MHz FLUP, diameter 7.3 mm, was used in this study. The mechanical shaft portion of the probe can be passed in retrograde fashion through the accessory channel of a standard colonoscope. Thirty-nine patients with rectal cancer underwent ultrasonography with this probe. The tumors were staged using the TNM system, and the results were compared with the histologic findings of the resected specimens.

RESULTS

The FLUP proved to be satisfactory, with respect to maneuverability, for traversing stenosis and accurate recognition of small tumors under direct endoscopic control. The accuracy of the FLUP for T staging was 82% (32 of 39) for all tumors, 90% in pT1, and 79% in pT2 to pT4 tumors. The accuracy of the FLUP for N staging was 72% (23 of 32) overall. The sensitivity was 83%, the specificity was 65%, the positive predictive value was 59%, and the negative predictive value was 87%.

CONCLUSIONS

The 7.5 MHz FLUP appears to be useful for preoperative local staging of rectal cancer. This system makes it technically easier to image small cancers as well as advanced rectal cancers.

Current status and future perspectives in gastric cancer management

Gastric cancer is still a major health problem and a leading cause of cancer mortality despite a worldwide decline in incidence. Environmental and Helicobacter pylori (Hp) acting early in life in a multistep and multifactorial process may cause intestinal type carcinomas, whereas genetic abnormalities are related more to the diffuse type of disease. Primarily due to early detection of the disease, the results of treatment for gastric cancer have improved in Japan, Korea and several specialized Western centres. Surgery offers excellent long-term survival results for early gastric cancer (EGC). Advances in diagnostic and treatment technology have contributed to a trend towards minimal invasive surgery such as endoscopic mucosal resection (EMR) and laparoscopic surgery for selected mucosal cancers. In the Western world, however, more than 80% of patients at diagnosis have an advanced gastric cancer with a poor prognosis. The aim of surgery is complete removal of the tumour (UICC R0-resection), which is known to be the only proven, effective treatment modality and the most important treatment-related prognostic factor. Gastrectomy with preservation of the spleen and pancreas in most cases is the standard procedure. However, at present there is no consensus about the optimal extent of lymph-node dissection. The hypothesis that extended (D2) lymph-node dissection leads to improved survival has not been confirmed in randomized trials. Results from specialized centres and ongoing multi-institutional randomized trials, however, indicate that D2 dissection, with preservation of the spleen and pancreas, can be performed with the same safety as a D1 dissection. Furthermore, in 50% of patients with node-positive disease, the extraperigastric N2 nodes are involved (N2 disease) and thus an R0-resection is achievable only by a D2 node dissection resulting in a 5-year survival of about 30% for such patients. However, even after a D2 node dissection with curative potential, disease recurs in two-thirds of patients with locally advanced gastric cancer (LAGC) and is rapidly fatal. The need for an adjuvant treatment is obvious, but at present there is no such treatment of proven effectiveness. Promising results with preoperative chemotherapy, which increases the R0-resection rate, and intra-or early postoperative intraperitoneal chemohyperthermia to prevent peritoneal dissemination have been reported. However, randomized trials are necessary before these combined treatments become widely accepted. Present data indicate that the treatment of gastric cancer has become more and more sophisticated with a tailored therapy for individual cases. Treatment includes a broad spectrum of therapeutic options from EMR for selected mucosal cancers to aggressive combined treatment for LAGC. Precise knowledge of patterns of recurrence and metastases, critical evaluation of clinicopathologic variables, integration of high technology into diagnosis to predict accurately pre-treatment staging, and the surgeon's ability to perform minimally invasive surgery and D2 node dissection technique are necessary for an appropriate treatment option. All these prerequisites are best ensured by management in experienced surgical oncology units.

Gastrointestinal miniprobe sonography: the current status

Endoscopic ultrasonography (EUS) represents a major advance in endoscopic imaging. The usefulness and effectiveness of EUS have been established during the past few years. However, endosonography using dedicated echoendoscopes (7.5/12 MHz) has some serious drawbacks, as follows: 1) Combining endoscopy and ultrasonography in one instrument increases the diameter of such echoendoscopes (12-13 mm); 2) Because of the large diameter, complete passage of severe strictures is often not possible and, for examination of the pancreatobiliary duct system, is not feasible at all; 3) Image quality and resolution for small lesions is not always satisfactory; and 4) Conventional endosonography requires a second examination separate from the previous routine endoscopy. Recently developed ultrasonographic miniprobes (diameters about 2 mm; frequencies 12-20 MHz) can be passed through the working channel of standard endoscopes to provide high frequency ultrasound images. These miniprobes might overcome some of the above-mentioned drawbacks and contribute to patients' security and convenience. Moreover, in various diseases of the GI tract and the pancreatobiliary duct system, diagnostic accuracy of miniprobe ultrasonography has been shown to be even superior to that of EUS. In summary, miniprobe ultrasonography seems to be a promising tool in the armamentarium of gastroenterological diagnostics.

Laparoscopically assisted distal gastrectomy for early gastric cancer: is it superior to open surgery?

BACKGROUND

The purpose of this study was to compare clinical outcomes between laparoscopically assisted and open distal gastrectomy for early gastric cancer.

METHODS

The records of 21 patients who underwent laparoscopically assisted distal gastrectomy (LG) for preoperative diagnosis of intramucosal gastric carcinoma between January 1996 and August 1998 were reviewed and compared with those of 31 open distal gastrectomy patients during the same period.

RESULTS

Age, gender, and size and histologic differentiation of the lesions were matched. Those located at the body of the stomach (p = 0.011) and those macroscopically depressed (p = 0.049) were subjected more frequently to open surgery. Laparoscopically assisted gastrectomy required significantly longer operative time (p < 0.001) with less extensive lymph node dissection (p < 0.001). However, time to start of walking (p = 0.032), time to flatus (p = 0.002), duration of postoperative fever (p = 0.027), and postoperative hospital stay (p = 0.001) were significantly shorter in the LG group, and this group had a lower white blood cell count on the first postoperative day (p = 0.010). Blood loss and time to oral intake were comparable between the groups. Complications included one conversion to open surgery, one leakage, and one stenosis in the LG group, and two leakages and an atelectasis in the OG group.

CONCLUSIONS

Although LG requires longer surgical time, this retrospective study suggests that it is superior to open surgery in terms of faster postoperative recoveries, shorter hospital stays, and cosmetic outcomes.

Laparoscopically assisted distal gastrectomy for early gastric cancer: is it superior to open surgery?

BACKGROUND

The purpose of this study was to compare clinical outcomes between laparoscopically assisted and open distal gastrectomy for early gastric cancer.

METHODS

The records of 21 patients who underwent laparoscopically assisted distal gastrectomy (LG) for preoperative diagnosis of intramucosal gastric carcinoma between January 1996 and August 1998 were reviewed and compared with those of 31 open distal gastrectomy patients during the same period.

RESULTS

Age, gender, and size and histologic differentiation of the lesions were matched. Those located at the body of the stomach (p = 0.011) and those macroscopically depressed (p = 0.049) were subjected more frequently to open surgery. Laparoscopically assisted gastrectomy required significantly longer operative time (p < 0.001) with less extensive lymph node dissection (p < 0.001). However, time to start of walking (p = 0.032), time to flatus (p = 0.002), duration of postoperative fever (p = 0.027), and postoperative hospital stay (p = 0.001) were significantly shorter in the LG group, and this group had a lower white blood cell count on the first postoperative day (p = 0.010). Blood loss and time to oral intake were comparable between the groups. Complications included one conversion to open surgery, one leakage, and one stenosis in the LG group, and two leakages and an atelectasis in the OG group.

CONCLUSIONS

Although LG requires longer surgical time, this retrospective study suggests that it is superior to open surgery in terms of faster postoperative recoveries, shorter hospital stays, and cosmetic outcomes.

Endoscopic ultrasonography in patients with gastro-esophageal cancer

For patients with gastro-esophageal cancer ultrasonography (EUS) is superior to any other imaging modality in the assessment of local tumor infiltration and local lymph nodes status. EUS is especially important in the preoperative staging of patients with esophageal cancer and patients with proximal gastric cancer. Here it allows for the identification of those patients with advanced disease who are unlikely to benefit from surgery and in whom a conservative palliative treatment is indicated. In advanced gastric cancer the clinical implications of EUS less clear. Still preoperative EUS is indicated in every patient with cancer of the proximal stomach to assess tumor infiltration in the esophagus. Relatively new is the use of EUS in staging early cancers in order to select patients for local endoscopic treatment. High-frequency miniprobes are the instruments of choice for imaging these lesions. Strict criteria should be applied in the selection of patients for local endoscopic treatment of early gastro-esophageal cancers. EUS guided fine needle aspiration (EUS-FNA) is currently only indicated in patients with esophageal cancer and suspicious celiac lymph nodes. It may become more important if new treatment protocols demand more objective and reliable assessment of lymph node status.

Current advances and changes in treatment strategy may improve survival and quality of life in patients with potentially curable gastric cancer

BACKGROUND

The treatment strategy for gastric cancer is determined by the stage of disease. Advances in diagnostic techniques such as endoscopic ultrasound (EUS) and in staging have increased the accuracy of pretreatment staging. Correct staging is a prerequisite for the optimal treatment of gastric cancer patients. Long-term expected survival and quality of life (QOL) are the major criteria determining the therapeutic strategy.

RESULTS

Surgical resection offers excellent survival rates for early gastric cancer (EGC) patients. D1 resection is sufficient for mucosal cancers (T1m) and for most submucosal cancers (Tlsm); however, for the rest (about 5%) of these patients with N2 disease a D2 resection is required for complete tumor resection (R0). Considering QOL, endoscopic mucosal resection (EMR) or laparoscopic wedge resection is the best front-line therapy for several mucosal cancers. Prediction and selection of node-negative patients with the help of certain macroscopic and histologic criteria can eliminate the possibility for residual disease in perigastric lymph nodes. However, long-term survival data are needed before these new techniques become more generally accepted. In contrast, an aggressive approach is necessary for the treatment of advanced gastric cancer. Total gastrectomy, with the exception of distal tumors that can be treated by subtotal gastrectomy, is the procedure of choice. Splenectomy is indicated for proximal advanced tumors. Distal pancreatectomy should be avoided, however, because its adverse effect has been documented in all randomized trials. Although the survival benefit of extended (D2) lymphadenectomy is unproven in randomized trials, D2 resection increases the R0 resection rate and may improve survival in some selected node-positive patients. D2 resection has little effect on preventing peritoneal tumor spread and liver metastasis, and the traditional late administration of chemotherapeutic drugs has been proven ineffective. Current data suggest a possible beneficial effect of combined treatment for patients with local advanced gastric cancer (LAGC). Ongoing phase-III randomized trials will prove whether patients with LAGC treated by neoadjuvant chemotherapy plus D2 resection versus surgery alone or surgery plus intraoperative intraperitoneal chemotherapy derive any benefit from these combined treatment modalities.

CONCLUSION

Evaluation of all information concerning tumor stage, location, histologic type, expected survival, and QOL after resection is of paramount importance for the surgeon planning the extent of surgery. The therapeutic approach should be stratified according to the stage of disease.

Transendoscopic ultrasound of esophageal and gastric cancer using miniaturized ultrasound catheter probes

BACKGROUND

The aim of this study was to investigate the value of miniaturized ultrasound catheter probes (miniprobes) for preoperative staging of esophageal and gastric cancer.

METHODS

Fifty-one patients with esophageal (n = 21) and gastric cancer (n = 30) underwent endoscopic ultrasound (EUS). All examinations were carried out using mechanical miniprobes (diameter 6F, 12.5 MHz) that were introduced through the instrument channel of the endoscope.

RESULTS

EUS with miniprobes was successfully performed in all patients, although stenotic tumors, which could not be traversed with the endoscope, were found in 6 of 21 patients (29%) with esophageal cancer. Miniprobe scanning provided high-resolution images of the gastrointestinal tract. The overall accuracy in the assessment of tumor infiltration depth for esophageal and gastric cancer was 90% and 82%, respectively. However, the value of miniprobe scanning in the assessment of advanced tumors was limited by the imaging depth of the probe (approximately 3 cm). Lymph node involvement was accurately diagnosed in 78% of the patients with esophageal cancer (sensitivity 75%, specificity 80%) and in 80% of the patients with gastric cancer (sensitivity 73%, specificity 89%).

CONCLUSIONS

EUS with miniprobes can be performed as single-step procedure during diagnostic endoscopy. The 12.5 MHz transducer provides high-resolution imaging and enables accurate staging of tumors with limited infiltration depth.