Principles of Surgical Radicality in the Treatment of Gastric Cancer

Down-regulated miRs specifically correlate with non-cardial gastric cancers and Lauren's classification system

BACKGROUND AND OBJECTIVES

Gastric cancers are usually characterized using Lauren's classification into intestinal and diffuse types. We previously documented the down-modulation of miR31, miR148a, miR204, and miR375 in gastric cancers. We aimed this manuscript to investigate these miRs with the end-points of diagnosis, Lauren's classification and prognosis.

METHODS

A total of 117 resected non-cardial adenocarcinomas were evaluated for miRs' expressions. The performance of miRs' expressions for cancer diagnosis was tested using ROC curves. Logistic regression was conducted with the end-point of Lauren's classification. Kaplan-Meier and Cox analyses were performed for OS, DFS, and DSS. miRs' targets were reviewed using PRISMA method and BCL-2 was further investigated in cell lines.

RESULTS

ROC curves documented that miRs' down-modulation was significant in differentiating cancer versus normal tissues. Diffuse type cancers were associated with female sex, young age, and miR375 higher expression. We confirmed BCL-2 as a miR204 target. However, survival analyses confirmed the pathologic criteria (advanced stages, LNR, and low LNH) as the significant variables correlated to worse prognosis.

CONCLUSIONS

The down-modulation of miR31, miR148a, miR204, and miR375 is significantly associated with non-cardial gastric cancers and miR375 is specifically linked to Lauren's classification. Nevertheless, standard pathological features display as the independent variables associated with worse prognosis.

Clinical Outcome of Positive Margin of Postgastrectomy with Adenocarcinoma of Stomach

<sec><title>Objectives</title> Many investigators have recommended adequate resection margin and lymphadenectomy for radical curative resection. The aim of this study is to evaluate clinical characteristics of positive resection margin (proximal or distal) of postgastrectomy in advanced gastric cancer. </sec><sec><title>Methods</title> We studied 17 patients with gastric cancer who were diagnosed positive resection margin by intraoperative frozen biopsy or permanent biopsy report from January 2005 to December 2007, retrospectively. Surgical margin monitored by endoscopy. </sec><sec><title>Results</title> Distal gastrectomy was performed in 13 patients and total gastrectomy in 4. Gastrectomy with combined resection including splenectomy was performed in 3, distal pancreatectomy in 2, transverse colon segmental resection in 1, and cholecystectomy in 2. Positive Proximal margin was found in 12, positive distal margin in 3, and both in 2. Palliative chemotherapy was performed in 8 patients. Postoperative follow up endoscopy was established in only 8 patients. Malignant results from endoscopic biopsy in gastroenteric or esophagoenteric anastomotic line were proven in 2 patients during follow up. 9 patients were not performed follow-up endoscopy. Among total 17 patients, 2 patients are alive. Fifteen patients died of aggravation of disease in 13 and postoperative complication in 2. </sec><sec><title>Conclusions</title> Although positive surgical margin in far advanced gastric cancer were found, it can consider that does not further resection to obtain microscopic clear anastomotic margin. </sec>

Treatment of resectable gastric cancer

Stomach cancer is one of the most common cancers worldwide, despite its declining overall incidence. Although there are differences in incidence, etiology and pathological factors, most studies do not separately analyze cardia and noncardia gastric cancer. Surgery is the only potentially curative treatment for advanced, resectable gastric cancer, but locoregional relapse rate is high with a consequently poor prognosis. To improve survival, several preoperative and postoperative treatment strategies have been investigated. Whereas perioperative chemotherapy and postoperative chemoradiation (CRT) are considered standard therapy in the Western world, in Asia postoperative monochemotherapy with S-1 is often used. Several other therapeutic options, although generally not accepted as standard treatment, are postoperative combination chemotherapy, hyperthermic intraperitoneal chemotherapy and preoperative radiotherapy and CRT. Postoperative combination chemotherapy does show a statistically significant but clinically equivocal survival advantage in several meta-analyses. Hyperthermic intraperitoneal chemotherapy is mainly performed in Asia and is associated with a higher postoperative complication rate. Based on the currently available data, the use of postoperative radiotherapy alone and the use of intraoperative radiotherapy should not be advised in the treatment of resectable gastric cancer. Western randomized trials on gastric cancer are often hampered by slow or incomplete accrual. Reduction of toxicity for preoperative and especially postoperative treatment is essential for the ongoing improvement of gastric cancer care.

Routine modified D2 lymphadenectomy performance in pT1-T2N0 gastric cancer

AIM: To evaluate routine modified D2 lymphadenectomy in gastric cancer, based on immunohistochemically detected skip micrometastases in level II lymph nodes.

METHODS: Among 95 gastric cancer patients who were routinely submitted to curative modified D2 lymphadenectomy, from January 2004 to December 2008, 32 were classified as pN0. All level I lymph nodes of these 32 patients were submitted to immunohistochemistry for micrometastases detection. Patients in whom micrometastases were detected in the level I lymph node stations (n = 4) were excluded from further analysis. The level II lymph nodes of the remaining 28 patients were studied immunohistochemically for micrometastases detection and constitute the material of the present study.

RESULTS: Skip micrometastases in the level II lymph nodes were detected in 14% (4 out of 28) of the patients. The incidence was further increased to 17% (4 out of 24) in the subgroup of T1-2 gastric cancer patients. All micrometastases were detected in the No. 7 lymph node station. Thus, the disease was upstaged from stage IA to IB in one patient and from stage IB to II in three patients.

CONCLUSION: In gastric cancer, true R0 resection may not be achieved without modified D2 lymphadenectomy. Until D2+/D3 lymphadenectomy becomes standard, modified D2 lymphadenectomy should be performed routinely.

Intraoperative margin re-resection for colorectal liver metastases

OBJECTIVE

Evaluate recurrence and survival in patients who underwent intraoperative margin re-resection for colorectal cancer liver (CRC) metastases.

DESIGN

Retrospective analysis.

SETTING

University Hospital, Cincinnati, Ohio. Academic medical center.

PARTICIPANTS

Cohort of 118 patients who underwent resection of CRC liver metastases between 1992 and 2004. All patients were divided into 3 groups: resection margin (MOR) less than 1 cm (n = 64), MOR greater than 1 cm (n = 33), and re-resection margin (re-MOR) greater than 1 cm (n = 21).

RESULTS

Patients with a margin greater than 1 cm, when compared with re-MOR greater than 1 had decreased incidence of liver and distant recurrence (p < 0.05) as well as improved disease-free survival (39.2 vs 22.9 months, p = 0.023). Differences in overall survival (58.6 vs 44.2 months, p = 0.14) were not significant.

CONCLUSION

Intraoperative re-resection is associated with an increased risk of local and distant recurrence, which may be a reflection of both inadequate surgery and underlying tumor biology.

Management of gastroesophageal tumors

The incidence of adenocarcinomas of the gastroesophageal junction has increased in recent years. These tumors possess distinct pathophysiologic characteristics. Although the consensus is that an R0 resection (complete microscopic and macroscopic resection) is the goal when operating for curative intent, much controversy remains regarding other aspects of patient management. There is lack of consensus regarding the type of surgery to perform, the role and extent of lymphadenectomy, and the role of neoadjuvant therapy. Utilizing an evidence-based approach, this review article provides an overview of the management of gastroesophageal junction carcinomas with particular emphasis on current areas of controversy.

[Laparoscopic gastrectomy in the treatment of gastric cancer]

OBJECTIVE

To present our initial results in the laparoscopic treatment of gastric cancer.

MATERIAL AND METHOD

Between March 2002 and June 2005, 12 selected patients with resectable distal gastric cancer and oncological indication for radical treatment underwent laparoscopic gastrectomy.

RESULT

There were 9 men and 3 women. The mean age was 62.6 years (range: 45-78). Ten D2 subtotal gastrectomies, with B-II reconstruction in 7 and B-III reconstruction in the remaining 3, were performed. In 6 patients, reconstruction was performed entirely by laparoscopy, while in the remaining 4 patients extracorporeal reconstruction was performed. Two total gastrectomies were performed: one was performed entirely by laparoscopy while in the other, laparoscopic-assisted gastrectomy with extracorporeal esophagojejunal anastomosis was carried out. The mean operating time was 197.6 +/- 36.9 (130-260) minutes, although mean operating time was 142.5 minutes in the subgroup that underwent subtotal gastrectomy with extracorporeal anastomosis compared with 190.8 minutes when totally laparoscopic anastomosis was performed (p < 0.002). There were no intraoperative complications or conversions. Postoperative complications occurred in 3 patients: postoperative ileus for 7 days in 1 patient, intra-abdominal abscess requiring laparotomy in 1 patient and esophagojejunal anastomotic leak that resolved without reintervention in a third patient. Oral intake was reinitiated at 72 hours in 9 patients, while a further 2 required 5 days and the patient with postoperative ileus required 8 days. The mean length of postoperative stay was 10.7 +/- 7.3 (6-28) days. The mean number of resected nodes was 21.3 +/- 5 (16-31). There was 1 locoregional recurrence at 14 months in a patient with stage IIIB tumor after a mean follow-up of 25.8 months (4-73).

CONCLUSIONS

Laparoscopic gastrectomy in the treatment of gastric cancer is technically feasible and is an alternative to open surgery in terms of postoperative morbidity and mortality and oncological effectiveness when performed by teams with experience in laparoscopy and with appropriate patient selection.

The role of chemotherapy in patients with established gastric cancer

Chemotherapy significantly improves survival in comparison to best supportive care in patients with metastasised gastric cancer. In patients for whom a three-drug-combination is considered as the treatment of choice, ECF (epirubicin, cisplatin and 5-FU as a continuous infusion) should be regarded as standard of care. However, results for ECF have been challenged by the recently presented REAL-2-trial, which demonstrated a significant survival benefit for EOX (epirubicin, oxaliplatin, capecitabine) over ECF. Adjuvant 5-FU-based chemoradiation should be discussed in patients with inadequate lymphadenectomy, but is not internationally accepted as standard of care: whether patients with adequate lymhphadenectomy benefit from adjuvant chemoradiotherapy is currently unclear. According to the results of the UK MAGIC trial, perioperative treatment with ECF (3 cycles prior to and post surgery) results in a significantly reduced risk of death for patients with resectable gastric cancer as compared to surgery alone. Neo-adjuvant chemotherapy has the ability to downsize gastric tumours and appears to improve R0-resection rates, but its potential to improve overall survival is still unclear.

Adjuvant therapy in gastric cancer

Gastric cancer has a poor prognosis. The majority of patients will relapse after definitive surgery, and 5-year survival after surgery remains poor. The role of adjuvant therapy in gastric cancer has been controversial given the lack of significant survival benefit in many randomized studies so far. The results of a large North American study (Gastrointestinal Cancer Intergroup Trial INT 0116) reported that postoperative chemoradiotherapy conferred a survival advantage compared with surgery alone, which has led to the regimen being adopted as a new standard of care. However, controversies still remain regarding surgical technique, the place of more effective and less toxic chemotherapy regimens, and the use of more modern radiation planning techniques to improve treatment delivery and outcome in the adjuvant and neoadjuvant setting. This article reviews the current status of the adjuvant treatment for gastric cancer including discussion on the research directions aimed at optimizing treatment efficacy. Issues such as the identification of patients who are more likely to benefit from adjuvant therapy are also addressed. Further clinical trials are needed to move towards better consensus and standardization of care.

Gastric adenocarcinoma: review and considerations for future directions

OBJECTIVE

This update reviews the epidemiology and surgical management, and the controversies of gastric adenocarcinoma. We provide the relevance of outcome data to surgical decision-making and discuss the application of gene-expression analysis to clinical practice.

SUMMARY BACKGROUND DATA

Gastric cancer mortality rates have remained relatively unchanged over the past 30 years, and gastric cancer continues to be one of the leading causes of cancer-related death. Well-conducted studies have stimulated changes to surgical decision-making and technique. Microarray studies linked to predictive outcome models are poised to advance our understanding of the biologic behavior of gastric cancer and improve surgical management and outcome.

METHODS

We performed a review of the English gastric adenocarcinoma medical literature (1980-2003). This review included epidemiology, pathology and staging, surgical management, issues and controversies in management, prognostic variables, and the application of outcome models to gastric cancer. The results of DNA microarray analysis in various cancers and its predictive abilities in gastric cancer are considered.

RESULTS

Prognostic studies have provided valuable data to better the understanding of gastric cancer. These studies have contributed to improved surgical technique, more accurate pathologic characterization, and the identification of clinically useful prognostic markers. The application of microarray analysis linked to predictive models will provide a molecular understanding of the biology driving gastric cancer.

CONCLUSIONS

Predictive models generate important information allowing a logical evolution in the surgical and pathologic understanding and therapy for gastric cancer. However, a greater understanding of the molecular changes associated with gastric cancer is needed to guide surgical and medical therapy.