Preoperative staging of gastric cancer as precondition for multimodal treatment

Preoperative predicting score of lymph node metastasis for gastric cancer

The aim of our study was to develop a new score system that might predict the probability of lymph node of gastric carcinoma. We studied the clinicopathological variables of 932 patients with gastric carcinoma admitted to the Department of Surgical Oncology at the First Hospital of China Medical University. Logistic analysis was performed to identify predictors. The hazard risk (HR) of variables obtained from logistic regression was used to construct a simple scoring system determined by an aggregate of the points assigned for each selected variable. Receiver operator characteristic (ROC) curve was created to analyze the specificity. Lymph node metastases were found in 644 (69.1 %) of 932 patients. After multivariate logistic regression analysis, tumor size, depth of invasion, and macroscopic types (P < 0.001) were selected as viable predictors to establish the scoring system. ROC curves were plotted to verify the accuracy of predicting score and other variables for both Lymph node stage (N stage) prediction. It showed that the predicting score system had a better specificity and sensitivity (65.71 % and 83.54 %, respectively). The current study suggests that a preoperative prediction system to identify the risk of lymph node metastasis is feasible. This model may be useful in preoperative counseling about the cost and benefit of systemic lymph node dissection.

Type IV collagen levels are elevated in the serum of patients with peritoneal dissemination of gastric cancer

Type III procollagen (amino-terminal propeptide of procollagen type III) and type IV collagen are considered to be reliable serum markers for monitoring the progression of liver fibrosis. The peritoneal dissemination of gastric cancer is also characterised by abundant collagen deposition in the peritoneum. The present study was performed to investigate the potential of serum type III procollagen and IV collagen as biomarkers for peritoneal dissemination in gastric cancer. The study population consisted of 117 patients with gastric cancer: 32 patients had peritoneal dissemination which was pathologically diagnosed by laparotomy or laparoscopic examination, while 85 patients (45/40, early/advanced gastric cancer) had no peritoneal dissemination. We measured the serum levels of type III procollagen and type IV collagen in comparison to the commonly accepted tumor markers carcinoembryonic (CEA), carbohydrate antigen (CA)19-9 and CA125. The median type III procollagen levels showed no significant differences between the two groups, whereas the median type IV collagen levels were significantly (201 ng/ml) higher in patients with than in those without peritoneal dissemination (early/advanced gastric cancer, 124/136 ng/ml) (P<0.05). In receiver operating characteristic (ROC) curve analysis, type IV collagen had the largest area under the curve (0.83), followed by CA125 (0.72), CA19-9 (0.64), CEA (0.59) and type III procollagen (0.48). Type IV collagen was an independent marker (P<0.0001, odds ratio 15.7) for predicting peritoneal dissemination along with CA125 (P=0.0086, odds ratio 9.4) based on multivariate logistic regression. In conclusion, serum type IV collagen levels may be significant in the early detection and management of patients with peritoneal dissemination of gastric cancer.

Gastric Adenocarcinoma: Is Computed Tomography (CT) Useful in Preoperative Staging?

BACKGROUND AND PURPOSE

Although multiple studies testing the accuracy of CT in the preoperative staging of gastric adenocarcinoma have been carried out, their results are controversial. Whilst some authors claim that CT is an accurate method for preoperatively staging gastric cancer, others have advocated the contrary. Because of this discrepancy we have retrospectively reviewed preoperative CT findings compared with histopathological results in patients with gastric adenocarcinoma.

PATIENTS AND METHODS

Seventy-two patients diagnosed with gastric cancer who underwent potentially curative surgery and preoperative staging CT of quality were included in the study. The size, gastric wall thickening, presence of lymphadenopathy, adjacent organ invasion and location of the gastric mass was recorded. Early tumors (T1 and T2) and more advanced tumors (T3 and T4) were grouped together. CT staging was correlated with the final histopathological stage (TNM). The global results were expressed as sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV).

RESULTS

Seventy-two cases were included with fifty-five being male and a median age of 67 years (range 33-91). CT correctly identified the location of the tumor in 56 (53% antropyloric, 18% subcardial). Median time from CT scan to surgery was fourteen days (range 2-49). In T detection: T1/T2 and T3/T4 with sensitivity of 70% and 61%. Lymph node involvement: Sensitivity 49%. Overstaged in 47% Understaged in 75%. Specificity of 53%. Nine patients with colon-mesocolon (5 patients) and pancreas (4 patients) invasion. Sensitivity 44% and specificity 96%.

CONCLUSION

Spiral CT is not an accurate method in predicting preoperative stages in gastric cancer.

Ecoendoscopia na avaliação pré-operatória do estádio em doentes com câncer gástrico: correlação com os achados cirúrgicos e/ou histopatológicos

RACIONAL: O câncer gástrico é a maior causa de morte por câncer no Brasil. Na avaliação do prognóstico e no planejamento da terapêutica, é importante determinar o estádio e classificá-lo em TNM. OBJETIVO: Estudar os resultados da ecoendoscopia na determinação pré-operatória das categorias T e N. MÉTODOS: Foram examinados prospectivamente e de forma consecutiva 30 pacientes com adenocarcinoma gástrico no período de 1 ano. Utilizou-se o aparelho Olympus GIF-UM-20. Após seu posicionamento na terceira porção duodenal, estudaram-se as estações linfonodais 16, 13, 12, 6, 5, 4, 3, 8, 7, 9, 10, 11, 1 e 2, usando a freqüência de 7,5 MHz. Os resultados T e N foram comparados com os achados cirúrgicos e/ou histopatológicos. Nos casos irressecáveis, a correlação foi feita com os achados macroscópicos. Para a análise estatística utilizou-se o teste de correlação coeficiente kappa. RESULTADOS: Foram realizadas 16 gastrectomias totais, 7 subtotais, 5 laparotomias exploradoras e 2 videolaparoscopias. Para a categoria T a ecoendoscopia acertou em 25/30 casos (83,3%). Todos os restantes 16,7% foram superestimados. A precisão variou de 90% a 96,7%, de acordo com as subdivisões T1 a T4. Para a categoria N, a ecoendoscopia foi correta em 23/30 casos (76,7%), sendo 16,6% subestimados e 6,7% superestimados. A precisão variou de 76,7% a 90%, de acordo com as subdivisões N0 a N2. CONCLUSÃO: Houve nítida correlação entre a ecoendoscopia pré-operatória e os achados cirúrgicos e/ou histopatológicos em pacientes com adenocarcinoma gástrico.

Comparison of CT and 18F-FDG pet for detecting peritoneal metastasis on the preoperative evaluation for gastric carcinoma

OBJECTIVE

The aim of our study was to compare the accuracy of CT and (18)FFDG PET for detecting peritoneal metastasis in patients with gastric carcinoma.

MATERIALS AND METHODS

One-hundred-twelve patients who underwent a histologic confirmative exam or treatment (laparotomy, n = 107; diagnostic laparoscopy, n = 4; peritoneal washing cytology, n = 1) were retrospectively enrolled. All the patients underwent CT and (18)F-FDG PET scanning for their preoperative evaluation. The sensitivities, specificities and accuracies of CT and (18)FFDG PET imaging for the detection of peritoneal metastasis were calculated and then compared using Fisher's exact probability test (p < 0.05), on the basis of the original preoperative reports. In addition, two board-certified radiologists and two board-certified nuclear medicine physicians independently reviewed the CT and PET scans, respectively. A receiver-operating characteristic curve analysis was performed to compare the diagnostic performance of CT and (18)F-FDG PET imaging for detecting peritoneal metastasis.

RESULTS

Based on the original preoperative reports, CT and (18)F-FDG PET showed sensitivities of 76.5% and 35.3% (p = 0.037), specificities of 91.6% and 98.9% (p = 0.035), respectively, and equal accuracies of 89.3% (p = 1.0). The receptor operating characteristics curve analysis showed a significantly higher diagnostic performance for CT (Az = 0.878) than for PET (Az = 0.686) (p = 0.004). The interobserver agreement for detecting peritoneal metastasis was good (kappa value = 0.684) for CT and moderate (kappa value = 0.460) for PET.

CONCLUSION

For the detection of peritoneal metastasis, CT was more sensitive and showed a higher diagnostic performance than PET, although CT had a relatively lower specificity than did PET.

Artificial neural network for prediction of lymph node metastases in gastric cancer: a phase II diagnostic study

BACKGROUND

Extension of lymphadenectomy in gastric cancer is controversial, and preoperative diagnosis of lymph node metastases (LNM) is difficult. Therefore, knowledge-based systems such as the Maruyama computer program (MCP) are being developed. MCP shows good prognostic value for the compartments; however, for different lymph node groups (LNG) there are a large number of false positives. The aim of this study was to evaluate artificial neural networks (ANN) for predicting LNM in patients with gastric cancer and to compare the predictive power with that of MCP.

METHODS

A total of 135 consecutive patients who underwent D2 gastrectomy were included. We applied a single-layer perceptron to the data of 4302 patients from the National Cancer Center, Tokyo, and compared the results with those from the MCP.

RESULTS

Prediction of N(+) or N0 with ANN-1 (Borrmann classification, T category, and tumor size and location) had an accuracy of 79%. The predictive value for LNM in each of the LNG varied: ANN-1, 64% to 86%; MCP, 42% to 70%. We constructed another ANN by using the additional parameter of metastases in LNG 3 as an example of sentinel node. The accuracy of this ANN was 93%.

CONCLUSIONS

Using an ANN, LNM in each LNG can be accurately predicted. Additional knowledge about one lymph node improves the results.

Individualizing therapy in gastric cancer

Although its incidence in developed countries has declined, gastric cancer remains one of the most common human malignancies. In western countries a shift from distal to proximal tumors has been noted during the past 15 years. Today, surgery is no longer the only treatment modality of gastric cancer, with the help of modern and sophisticated staging procedures it becomes increasingly possible to individually tailor therapy. Operative morbidity and mortality has markedly decreased. The importance of surgical expertise for short- as well as long-term outcome is emphasized. The knowledge of adequate surgery together with the use of combined modalities opens the door to the amelioration of the still dismal prognosis for patients with gastric cancer. This paper reviews the modern approach to gastric cancer using an individualized treatment concept.

Impact of perioperative intraperitoneal chemotherapy on the treatment of primary gastric cancer

Perioperative intraperitoneal chemotherapy provides effective prevention of peritoneal recurrence after resection in advanced gastric cancer, especially in gastric cancer with serosal invasion. With improved local-regional control, improved survival rate for advanced gastric cancer is achieved. This type of regional chemotherapy is an independent treatment-related prognostic factor for advanced gastric cancer. There are several methods of perioperative intraperitoneal chemotherapy. Among them, early postoperative intraperitoneal chemotherapy is simple and easy to perform.

The role of pretherapeutic laparoscopy in the selection of treatment for patients with gastric carcinoma: a proposal for a laparoscopic staging system

BACKGROUND

A pretherapeutic staging system to design nonoperative or neoadjuvant treatments in gastric cancer is required. In this study, a simple staging system based on laparoscopic findings to define a treatment algorithm was developed.

METHODS

A retrospective cohort study was conducted of 151 patients allocated into four stages based on laparoscopic findings. The depth of tumor invasion and the presence of metastasis based on laparoscopic findings were used to construct these stages. Laparoscopic findings were compared with histopathology.

RESULTS

An excellent agreement of the laparoscopy-defined depth of invasion and the surgical pathology standard was found (weighted kappa 0.85). The likelihood ratios for a positive and negative laparoscopic diagnosis of metastasis were 40.4 and 0.015, respectively (98.5% sensitivity, 97.6% specificity). Those for positive and negative diagnosis of resectability were 2.6 and 0.03, respectively (98.4% sensitivity, 62% specificity). The laparoscopic stages presented significant prognostic value. Two-year survival was 93%, 69%, 60%, and 17%, respectively. Surgical resection was possible in 100%, 100%, 49%, and 12%, respectively.

CONCLUSIONS

The proposed laparoscopic staging system is a simple and reproducibLe way for selection of a suitable therapy. It allows for adequate stratification of the main risk factors in the setting of clinical trials evaluating preoperative treatments.

Neoadjuvant chemotherapy, radical resection with intraoperative radiation therapy (IORT): improved treatment for gastric adenocarcinoma

BACKGROUND

Adenocarcinoma of the stomach and gastroesophageal junction results in substantial morbidity, locoregional recurrence, and death. Surgical procedures, even with adjuvant therapy, have not significantly improved survival. This study evaluated the toxicity, response rate, locoregional control, and survival of patients with locally advanced gastric cancer that was treated with neoadjuvant multimodality therapy.

METHODS

Patients with stage IIIA or early stage IV gastric adenocarcinoma received neoadjuvant 5-fluorouracil, Leucovorin, Adriamycin, and Cisplatin and underwent gastrectomy or esophagogastrectomy with intraoperative radiotherapy (IORT; 1000 cGY) to the gastric bed and postoperative radiation therapy.

RESULTS

Nine of 15 patients (60%) with transmural extension and/or nodal metastases received IORT. There were 2 pathologically complete responses at the primary site. Eleven of 15 patients (73%) had tumor in perigastric lymph nodes; however, 9 of 15 patients (60%) had mucin-filled nodes without tumor cells. Neoadjuvant treatment did not increase operative morbidity rates. Ten of 15 patients (67%) remain free of disease (median, 27 months; range, 6-60 months). Five patients died 13 to 41 months (median, 17 months) after diagnosis.

CONCLUSIONS

Neoadjuvant multimodality therapy with neoadjuvant 5-fluorouracil, Leucovorin, Adriamycin, and Cisplatin, radical resection with IORT, and postoperative radiation therapy is safe, can downstage tumors, provides improved locoregional control, and appears to cause significant tumor regression that may result in long-term survival or cure.

Role of laparoscopy in the staging of malignant disease

Although diagnostic laparoscopy has been used by surgeons and gastroenterologists since the early 1900s, today's surgical oncologists have been relatively slow to embrace this technology. Together with the fervor and benefits afforded by laparoscopic therapeutic interventions in the management of patients with benign disease and the diagnostic usefulness in blunt trauma and abdominal pain, awareness has been rekindled regarding the advantages of laparoscopy for the staging of abdominal malignancy. As surgeons begin to realize that extirpative procedures are doomed to failure in curing patients with diffuse abdominal metastases disclosed on laparoscopic assessment, palliative measures, such as stent placement, ablative procedures, balloon dilatation, intraluminal high-dose radiation, and laser techniques will be used commonly by surgical endoscopists and gastroenterologists. Similarly, it is hoped that the use of systemic chemotherapy will achieve better specificity in cell destruction in patients identified laparoscopically to have uncontained disease in the abdominal cavity. The sensitivity of sonography combined with laparoscopy has been shown to approach that of celiotomy in the evaluation of solid organs, thereby avoiding unnecessary laparotomy and its associated morbidities. Using sonography as a complement to laparoscopy will extend the usefulness of both techniques. The application of laparoscopy and the advent of miniaturized laparoscopic instrumentation (Fig. 7), both diagnostic and therapeutic, in the management of patients with abdominal malignancy will be limited only by the creativity and expertise of physicians and instrument makers.

Multidisciplinary approach to esophageal and gastric cancer

Despite marked advances in surgical therapy for patients with esophageal, esophagogastric, and gastric cancers, the overall prognosis of these patients has not markedly improved during the past decades. Multidisciplinary approaches using adjuvant postoperative and neoadjuvant preoperative therapeutic principles have received increasing attention with regard to the management of these patients. A series of randomized, prospective trials has demonstrated that adjuvant postoperative radiation or chemotherapy does not result in a convincing survival advantage after complete tumor resection in esophageal, esophagogastric junction, or gastric cancer. The available data on the role of neoadjuvant preoperative therapy are not yet conclusive. Although neoadjuvant therapy may reduce the tumor mass in many patients, several randomized, controlled trials have shown that, compared with primary resection, a multimodal approach does not result in a survival benefit in patients with locoregional, that is, potentially resectable, tumors. In contrast, in patients with locally advanced tumors, that is, patients in whom complete tumor removal with primary surgery seems unlikely, neoadjuvant therapy increases the likelihood of complete tumor resection on subsequent surgery, but only patients with objective histopathologic response to preoperative therapy seem to benefit from this approach. Consequently, in the future, improvements in the overall survival of patients with esophageal, esophagogastric junction, or gastric cancer most likely will be achieved only by tailored therapeutic strategies that are based on the individual tumor location, tumor stage, and consideration of established prognostic factors. A clear classification of the underlying tumor entity, a profound knowledge of the prognostic factors applicable, a thorough preoperative staging, and identification of parameters that allow for the prediction of response to preoperative therapy will become essential for the selection of the optimal therapeutic modality for individual patients.

Imaging diagnosis for staging of gastric cancer

A more differentiated therapy regimen concept for gastric cancer requires more precise pre-operative diagnostic imaging. There are several methods for pre-operative locoregional tumor staging in gastric cancer: percutaneous abdominal ultrasound with hydrotechnique (HUS), endoluminal ultrasound in the stomach (EUS), computed tomography (CT), and magnetic resonance imaging (MRI). The advantages and indications for each method are described and an overview of the medical literature is given. The results in the literature are compared to our own findings, which were obtained in prospective studies comparing the four different imaging methods. On the basis of our experience and the literature, we conclude that the indication for the different diagnostic imaging methods primarily depends on the type of therapy concept followed in the respective surgical department. Endoscopy with biopsy remains the primary diagnostic procedure. Endosonography (EUS) is another diagnostic procedure, which can be performed simultaneously with endoscopy. Only special questions or reasons warrant the use of other imaging methods.

Cytology of peritoneal lavage performed during staging laparoscopy for gastrointestinal malignancies: is it useful?

OBJECTIVE

To evaluate the potential benefit of cytology of the peritoneal lavage obtained during diagnostic laparoscopy for staging gastrointestinal (GI) malignancies.

SUMMARY BACKGROUND DATA

Peritoneal lavage is a simple procedure that can be performed during laparotomy for GI tumors. Tumor cells in the lavage fluid are thought to indicate intraperitoneal tumor seeding and to have a negative effect on survival. For this reason, peritoneal lavage is frequently added to diagnostic laparoscopy for staging GI malignancies.

METHODS

Patients who underwent peritoneal lavage during laparoscopic staging for GI malignancies between June 1992 and September 1997 were included. Lavage fluids were stained using Giemsa and Papanicolaou methods. Cytology results were correlated with the presence of metastases and tumor ingrowth found during laparoscopy and with survival.

RESULTS

Cytology of peritoneal lavage was performed in 449 patients. Tumor cells were found in 28 patients (6%): 8/87 with an esophageal tumor, 2/32 with liver metastases, 11/72 with a proximal bile duct tumor, 7/236 with a periampullary tumor, and none in 7 and 15 patients with a primary liver tumor or pancreatic body or tail tumor, respectively. In 19 of the 28 patients (68%) in whom tumor cells were found, metastatic disease was detected during laparoscopy, and 3 of the 28 patients had a false-positive (n = 1) or a misleading positive (n = 2) lavage result. Therefore, lavage was beneficial in only 6/449 patients (1.3%); in these patients, the lavage result changed the assessment of tumor stage and adequately predicted irresectable disease. Univariate analysis showed a significant survival difference between patients in whom lavage detected tumor cells and those in whom it did not, but multivariate analysis revealed that these survival differences were caused by metastatic or ingrowing disease.

CONCLUSION

Cytology of peritoneal lavage with conventional staining should no longer be performed during laparoscopic staging of GI malignancies because it provides an additional benefit in only 1.3% of patients and has limited prognostic value for survival in this group of patients.

Adenocarcinoma of the gastro-esophageal junction: CT for monitoring during neoadjuvant chemotherapy

OBJECTIVE

A clinical study was performed to assess the diagnostic value of spiral CT for evaluation of response during neoadjuvant chemotherapy (CTx) in patients with adenocarcinoma of the gastro-esophageal-junction (GEJ). Results were compared to those of endoscopy.

METHODS AND MATERIAL

Twenty-five patients with histologically proven adenocarcinoma of the GEJ scheduled to undergo neoadjuvant CTx were studied. Before CT examination, 1200 ml of a vanilla flavoured paraffin emulsion were applied orally to the fasting patients and 40 mg BuscopanR or 2 mg glucagon were injected i.v. for hypotonia. Iodine (100 ml) was injected automatically (3 ml/s) and the CT scan was started 10 s after complete administration of CM. For response evaluation to CTx, four standardized parameters were measured by two experienced, blinded radiologists. The results were categorized according to the WHO classification of 1981 and compared to those of endoscopy.

RESULTS

In 24 of 25 patients endoscopic and computed tomographic response evaluation showed a close correlation (r = 0.96).

CONCLUSION

Spiral CT with negative oral contrast agent is a suitable technique for monitoring of GEJ masses. In combination with standardized metric parameters it offers a quantitative response evaluation in patients with GEJ masses during neoadjuvant CTx.

Neoadjuvant chemotherapy for gastric cancer: update

Neoadjuvant chemotherapy has recently received increasing attention in an attempt to increase the rate of complete tumor resections, combat systemic metastases, and prolong survival in patients with gastric cancer. The available data indicate that neoadjuvant chemotherapy is feasible and does not increase postoperative morbidity and mortality. Compared to the results that can today be obtained with primary resection and lymphadenectomy, however, preoperative chemotherapy has so far failed to show a clear increase in the rate of complete tumor removal in patients with resectable gastric cancer. In patients with locally advanced or unresectable gastric cancer, preoperative chemotherapy may cause substantial reduction in locoregional tumor mass and thus increase the resection rate. This finding appears to translate into a survival benefit for those who respond to chemotherapy and have subsequent complete tumor resection. Because of severe shortcomings in the study design of the published reports, definite conclusions cannot be drawn from the available studies. Randomized controlled prospective trials are therefore clearly warranted. Exact pretherapeutic tumor staging, standardized resection and lymphadenectomy techniques, diligent evaluation of the resected specimen, and close follow-up are essential when designing these trials to identify subgroups of patients who may benefit from neoadjuvant chemotherapy for gastric carcinoma.