A review of adjuvant therapy for resected primary gastric cancer with an update on Taegu's phase III trial with intraperitoneal chemotherapy

Recent Advances in Intra-peritoneal Chemotherapy for Gastric Cancer

Peritoneal metastasis (PM) frequently occurs in patients with gastric cancer (GC) and confers a dismal prognosis despite advances in systemic chemotherapy. While systemic chemotherapy has poor peritoneal penetration, intraperitoneal (IP) chemotherapy remains sequestered, resulting in high peritoneal drug concentrations with less systemic side-effects. The first application of IP treatment was hyperthermic intraperitoneal chemotherapy (HIPEC) with cytoreductive surgery (CRS) for gastric cancer peritoneal metastasis (GCPM); but was associated with an increased morbidity and mortality rate without significantly improving overall survival (OS). While CRS confers limited benefit, the potential role of prophylactic HIPEC and laparoscopic neoadjuvant HIPEC are currently being evaluated. Combination systemic and IP chemotherapy (SIPC) gained popularity in the 1990s, since it provided the benefits of IP treatment while reducing surgical morbidity, demonstrating promising early results in multiple Phase II trials. Unfortunately, these findings were not confirmed in the recent PHOENIX-GC randomized controlled trial; therefore, the appropriate treatment for GCPM remains controversial. Small observational studies from Japan and Singapore have reported successful downstaging of PM in GC patients receiving SIPC who subsequently underwent conversion gastrectomy with a median OS of 21.6–34.6 months. Recently, the most significant development in IP-directed therapy is pressurized IP aerosol chemotherapy (PIPAC). Given that aerosol chemotherapy achieves a wider distribution and deeper penetration, the outcomes of multiple ongoing trials assessing its efficacy are eagerly awaited. Indeed, IP-directed therapy has evolved rapidly in the last 3 decades, with an encouraging trend toward improved outcomes in GCPM, and may offer some hope for an otherwise fatal disease.

Evolution of management in peritoneal surface malignancies

Management of peritoneal surface malignancies has gradually evolved by the introduction of cytoreductive surgery in combination with intraperitoneal chemotherapy applications. Recently, peritoneal metastases of intraabdominal solid organ tumors and primary peritoneal malignancies such as peritoneal mesothelioma are being treated with this new approach. Selection criteria are important to reduce morbidity and mortality rates of patients who will experience minimal or no benefit from these combined treatment modalities. Management of peritoneal surface malignancies with this current trend is presented in this review.

Current status of management of malignant disease: current management of gastric cancer

Despite a continually decreasing incidence trend, gastric cancer remains a high-risk malignancy. Symptoms are often unspecific, and upper gastrointestinal endoscopy is the key modality for diagnosing early and intermediate-stage disease. Surgeons play a critical role in guiding and managing multiple aspects of gastric cancer diagnosis and care. Potentially curable gastric adenocarcinoma has to be free of distant metastasis and should be staged through endoscopic ultrasound and computed tomography. Early (T1N0) gastric cancer can be considered for endosopic mucosal resection or submucosal dissection. All other M0 stage groups should be evaluated for preoperative chemotherapy or chemoradiation followed by resection through a multidisciplinary approach. Laparoscopic staging, complete (R0) resection, and extended lymphadenectomy (D2 dissection) are critical operative components that optimize curability during gastrectomy. The morbidity potential after gastrectomy remains high; splenectomy and distal pancreatectomy should be avoided if possible to minimize postoperative complications. Laparoscopic gastric cancer resections are increasingly pursued and have not shown disadvantages to open gastrectomy as long as oncologic principles are followed. For the palliation of specific symptoms in patients with incurable gastric cancer, operative interventions should be applied selectively if less invasive modalities are insufficient and only if a meaningful benefit can be expected from a resection or bypass procedure. Prophylactic total gastrectomy should be considered for individuals at risk for hereditary diffuse-type gastric cancer through germline E-cadherin gene mutations. Surgeons engaging in gastric cancer care are expected to provide specialty expertise in order to plan and deliver appropriate care, minimize postoperative morbidity, and optimize resulting survival.

Early postoperative intraperitoneal chemotherapy for macroscopically serosa-invading gastric cancer patients

PURPOSE

Peritoneal recurrence is one of the most common patterns of recurrence after gastric cancer surgery and it has a poor prognosis despite all efforts. The aim of this study is to evaluate the prognostic impact of early postoperative intraperitoneal chemotherapy (EPIC) after surgery with curative intent for macroscopically serosa-invading gastric cancer patients.

MATERIALS AND METHODS

The records of 245 patients under the age of 70 were reviewed. These patients were suffering from macroscopically seroa-invading gastric cancer and they underwent curative surgery from 1995 to 2004 at the Kyungpook National University Hospital, Daegu, Korea. The overall survival, gastric cancer-specific survival, complications, and patterns of recurrence were compared between the patients who were treated with EPIC and those who were not.

RESULTS

EPIC was administered to 65 patients, and the remaining 180 patients did not receive this treatment. The 5-year overall and gastric cancer-specific survival rates for the EPIC group were 47.4% and 53.1%, respectively, and those for the non-EPIC group were 26.7% and 29.7%, respectively (p=0.012 for overall survival and p=0.011 for gastric cancer-specific survival). The rates of peritoneal recurrence for the EPIC group and the non-EPIC group were 18.5% and 32.2%, respectively (p=0.038). There were no significant differences in the morbidity or mortality between the two groups. Based on a multivariate analysis of the factors with prognostic significance in univariate analyses, EPIC, pathological lymph node metastasis, differentiation, and the extent of gastric resection were independent prognostic factors.

CONCLUSION

The use of EPIC to treat gastric cancer patients with macroscopic serosal invasions resulted in better survival rate by reducing the risk of peritoneal recurrence.

Cyto-reductive Surgery combined with Hyperthermic Intra-peritoneal Chemotherapy for Peritoneal Surface Malignancies: current treatment and results

Cyto-reductive Surgery (CS) combined with Hyperthermic Intra-peritoneal Chemotherapy (HIPEC) as loco-regional treatment of Peritoneal Surface Malignancies (PSM) has increasingly gained acceptance in clinical practice. This review summarizes the more relevant studies on this topic. Indications, pre-operative work-up, technical aspects, outcome and future directions of this combined approach in the treatment of Peritoneal Surface Malignancies are discussed here and proposed in an informative and didactic manner.

Retrospective analysis of adjuvant intraperitoneal chemotherapy effect prognosis of resectable gastric cancer

OBJECTIVE

This study evaluated the efficacy and safety of adjuvant intraperitoneal perfusion chemotherapy (IPC) in resectable gastric cancer through retrospective analysis.

METHODS

Three hundred and sixty T2-4bN0-3M0 resectable gastric cancer patients were included in this study. One hundred and eighty-four patients used systemic chemotherapy combined with IPC (IP+ group) and 176 systemic chemotherapy only (IP- group).

RESULTS

With a median of 49.9 months of follow-up, the 5-year overall survival in IP+ patients was significantly better than in IP- patients (60.4 vs. 42.9%; p = 0.001), and the average progression-free survival in IP+ patients was significantly longer than in IP- patients (60.5 vs. 46.2 months; p = 0.001). Relapse rates of peritoneal carcinomatosis, celiac lymph node and hepatic metastasis in the IP+ patients were significantly lower than in the IP- patients. Patients with curative resection, a histological type other than mucinous adenocarcinoma and signet ring cell carcinoma, low and undifferentiated tumor grade, lymph node metastasis, and T3 and T4a benefited from adjuvant IPC. The toxicities were the same except for more patients with leukopenia in the IP+ group (p = 0.001). The number of cycles of IPC and the time of IPC start after surgery had an impact on overall and disease-free survival.

CONCLUSION

Adjuvant IPC for resectable gastric cancer gave encouraging results and large multicenter prospective randomized controlled studies are warranted.

Updating controversies on the multidisciplinary management of gastric cancer

The rates of relapse and death remain high in gastric cancer patients, especially in advanced stages. Local relapses in the tumour bed and regional lymph nodes, peritoneal spread as abdominal carcinomatosis, and distant metastasis are common mechanisms of failure after a R0 resection. To overcome this, a multidisciplinary approach has been prompted. In recent years, multidisciplinary treatment has been strengthened by some randomised controlled trials and it is now considered the standard by most groups, although the improvement in long-term survival rates achieved is still limited. This new therapeutic approach in gastric cancer is rapidly evolving and has led to a series of controversies on the best strategy to follow. Some of these controversies are discussed in this paper.

Locoregional treatment of peritoneal carcinomatosis from gastric cancer

The authors reviewed the natural history and the main features of the peritoneal carcinomatosis from gastric cancer briefly and analyzed the pertinent literature concerning the locoregional modalities for prevention and for treatment. Results of the web based voting by experts were also summarized. As regards the peritoneal perfusion with cytotoxic drugs with or without hyperthermia for preventing peritoneal carcinomatosis in high risk patients, there are some randomized clinical trials and one meta-analysis supporting a benefit of the procedure. However, disparity in methodology (drugs, dosage, duration of the treatment, addition of hyperthermia, etc.) precludes the adoption of a shared protocol to be used in the clinical practice in high risk patients. Once the peritoneal carcinomatosis is established, the approach reported in literature is the peritonectomy associated with hyperthermic perfusion. However, data supporting benefits are scanty, and limited to few centers with a specific experience in this field. With regard to the main questions addressed to the experts' panel and concerning the indications for treatment and methodology, there was a general consistency among the experts and agreement with the findings of the literature. The need for a large multicenter trial to confirm the benefit and risk of intraperitoneal chemotherapy was recognized by both the experts and the authors.

Management of gastric adenocarcinoma

Gastric adenocarcinoma is the second most common cause of cancer death worldwide. The prognosis for patients with gastric adenocarcinoma depends on the stage of the disease at the time of diagnosis and treatment. Early gastric cancer, limited to the mucosa and submucosa, is best treated surgically and has a five-year survival rate of 70-95%. Surgical resection remains the primary curative treatment for localised disease. Despite this, the overall survival remains poor. The management of localised gastric adenocarcinoma is complex, and at present there is proven benefit of both preoperative chemotherapy and postoperative chemoradiotherapy. There is no standard regimen of chemotherapy for metastatic disease, although the regimen of ECF (epirubicin, cisplatin and fluorouracil) is the most used regimen, with a median survival of 7-9 months. With new regimens of chemotherapy, such as DCF (docetaxel, cisplatin and fluorouracil) or the combination of irinotecan, cisplatin and bevacizumab, the median survival has increased. Other new agents are under investigation.

Palliative management of gastric cancer

Advanced gastric cancer and its palliative treatment have a long and interesting history. Today, gastric adenocarcinoma is the second leading cause of cancer death worldwide. Unfortunately, many cases are not diagnosed until late stages of disease, which underscores the importance of the palliative treatment of gastric cancer. Palliative care is best defined as the active total care of patients whose disease is not responsive to curative treatment. Although endoscopy is the most useful method for securing the diagnosis of gastric adenocarcinoma, computed tomography may be useful to assess local and distant disease. The main indication for the institution of palliative care is the presence of advanced gastric cancer for which curative treatment is deemed inappropriate. The primary goal of palliative therapy of gastric cancer patients is to improve quality, not necessarily length, of life. Four main modalities of palliative therapy for advanced gastric cancer are discussed: resection, bypass, stenting, and chemotherapy. The choice of modality depends on a variety of factors, including individual patient prognosis and goals, and should be made on case-by-case basis. Future directions include the discovery and development of serum or stool tumor markers aimed at prevention, improving prognostication and stratification, and increasing awareness and education.