Adjuvant chemotherapy for gastric cancer with S-1, an oral fluoropyrimidine

Feasibility and accuracy of second-look laparoscopy after gastrectomy for gastric cancer

BACKGROUND

A better method for detecting early peritoneal progression is needed. This study evaluated the feasibility and accuracy of second-look laparoscopy for patients with gastric cancer treated using systemic chemotherapy after gastrectomy.

METHODS

Second-look laparoscopy was conducted for patients who had no clinical evidence of distant metastases but had peritoneal metastases or positive peritoneal cytology results without visible metastatic disease at initial surgery, patients who underwent systemic chemotherapy over a 6-month period after surgery, and patients who had no clinical evidence of disease based on imaging study after completion of primary chemotherapy.

RESULTS

Between November 2004 and April 2008, 21 patients underwent second-look laparoscopy. At the initial surgery, 13 of these patients underwent total gastrectomy and 8 patients underwent distal gastrectomy. One or two sheets of adhesion barrier were received by 18 patients. The median interval between initial surgery and second-look laparoscopy was 9.8 months (range, 6.6-17.5 months). All second-look procedures were completed laparoscopically, and no patients required conversion to laparotomy. None of the 21 patients experienced postlaparoscopy complications. Whereas 12 patients showed no pathologic evidence of disease, 9 patients showed disease at second-look laparoscopy. There was a significant difference in median survival between the groups with negative and positive results (p = 0.017). The median survival for the negative group has not been determined. All the patients in the positive group received further chemotherapy while showing a good performance status (PS). Six patients were PS 0, and 3 patients were PS 1. The median survival time for this group was 10.1 months.

CONCLUSIONS

Second-look laparoscopy was a safe and promising approach to reassessment of peritoneal disease for patients with gastric cancer. The incidence of complications was low, particularly in this group of patients, all of whom had undergone prior gastrectomy.

Prognostic significance of peritoneal washing cytology in patients with potentially resectable gastric cancer

BACKGROUND/AIMS

The prognostic value of cytological examination of intraoperative washings in potentially resectable gastric cancer is controversial.

METHODOLOGY

Between February 1993 and August 2001, clinicopathological features and surgical outcome of 26 consecutive patients with gastric cancer with positive cytological findings of peritoneal washings without peritoneal dissemination were retrospectively analyzed.

RESULTS

The overall 1, 2, 3-year survival rates for 26 patients were 69%, 35%, and 0%, respectively. The median survival was 17.5 months. The median survival of patients with curative resection (n=16) and non-curative resection (n=10) was 19 months and 12.5 months, respectively. There was no significant difference in survival between curative resection and non-curative resection (p=0.10). Recurrent disease frequently occurred as peritoneal dissemination (69%). No patient survived for more than 34 months.

CONCLUSIONS

Aggressive surgical resections do not provide any survival benefit for gastric cancer with positive cytological findings of peritoneal washings even in the absence of peritoneal dissemination.

Meta-analysis of adjuvant chemotherapy after radical surgery for advanced gastric cancer

BACKGROUND

There is no consensus of opinion about postoperative adjuvant chemotherapy after radical surgery for advanced gastric cancer. This is a meta-analysis of the published results of relevant randomized clinical trials (RCTs).

METHODS

Electronic databases from January 1998 to December 2007 were searched and 12 RCTs were selected. These included a total of 3809 patients. The hazard ratio (HR) for overall survival was calculated.

RESULTS

The pooled HR for overall survival was 0.78 (95 per cent confidence interval 0.71 to 0.85) in favour of chemotherapy. Subgroup analysis showed that the advantage of chemotherapy was not influenced by depth of tumour infiltration, status of lymph node metastasis, type of lymphadenectomy, geographical distribution of patients or route of drug administration.

CONCLUSIONS

Postoperative chemotherapy can improve overall survival after radical surgery for gastric cancer; there is no standardized chemotherapy regimen. Japanese-style D2 radical surgery plus oral 5-fluorouracil appears an effective treatment at present.

The prognostic impact of isolated tumor cells in lymph nodes of T2N0 gastric cancer: comparison of American and Japanese gastric cancer patients

BACKGROUND

The clinical significance of immunohistochemically detected isolated tumor cells (ITC) in lymph nodes of gastric cancer patients is controversial. This study examined the prognostic impact of ITC on patients with early-stage gastric cancer in two large volume centers in the United States and Japan.

METHODS

Fifty-seven patients with T2N0M0 gastric carcinoma who underwent gastric resection between January 1987 and January 1997 at Memorial Sloan-Kettering Cancer Center (MSKCC) in New York and 107 patients resected at National Cancer Center Hospital (NCCH) in Tokyo between January 1984 and December 1990 were studied. The sections were newly prepared from each lymph node for immunohistochemical staining for cytokeratin. Lymph nodes and original specimens from MSKCC were examined by pathologists in NCCH. The prognostic significance of the presence of ITC in lymph nodes was investigated in patients of both institutions.

RESULTS

ITC were identified in 30 of 57 patients (52.6%) at MSKCC and in 38 of 107 patients (35.5%) at NCCH. In both institutions, there was no significant difference in the prognosis of the studied patients with or without ITC (P= .22, .86 respectively).

CONCLUSIONS

The presence of ITC detected by immunohistochemistry in the regional lymph nodes did not affect the prognosis of American and Japanese patients with T2N0M0 gastric carcinoma who underwent gastrectomy with D2 lymph node dissection.

Comparison of alternate-day versus consecutive-day treatment with S-1: assessment of tumor growth inhibition and toxicity reduction in gastric cancer cell lines in vitro and in vivo

BACKGROUND

The toxic effects of S-1 can lead to discontinuation of treatment. Strategies for reducing toxicity without compromising therapeutic effectiveness are required.

METHODS

We used the human gastric cancer cell lines MKN28 and MKN45 to examine such strategies in vitro. The cell lines were treated with three different regimens, given on alternate days (alternate-day) or on consecutive days (consecutive-day). On consecutive days, treatment A provided the same total dose as the alternate-day treatment, and treatment B was given for the same number of days as the alternate-day treatment. A fourth group served as control. In vitro, the relative inhibition (RI) of tumor growth by 5-fluorouracil was calculated using the 2-(2-methyl-4-nitrophenyl)-3-(4-nitrophyl)-5-2, 4-disulfophenyl)-2H-tetrazolium (WST-8) method. We also carried out an in vivo experiment in which tumor-bearing nude mice (BALBc/nu-nu) were used to examine the antitumor activity of S-1. Leukocyte counts and gastrointestinal mucosal injury were compared in mice that received alternate-day and consecutive-day treatments.

RESULTS

In vitro, for MKN28, the RI was 22.9% for alternate-day, 34.1% for consecutive-day A, and 37.7% for consecutive-day B treatments. For MKN45, the RI was 51.1% for alternate-day, 52.2% for consecutive-day A, and 50.5% for consecutive-day B treatments. In vivo, for MKN28, the treated groups showed higher inhibition than the control, and inhibition of tumor growth was higher with alternate-day than with consecutive-day treatment. The RI was significantly higher with alternate-day (49.3%) than with consecutive-day treatment (16.2%; P < 0.05). For MKN45, the RI was greater than 50% in both treated groups. With consecutive-day treatment, 5 of the 14 mice used died during treatment. Leukocyte counts were lower in the mice with consecutive-day than with alternate-day treatment, or control. Atrophic changes and inflammatory cell infiltration of the small intestinal mucosa were severe after consecutive-day, but minimal after alternate-day treatment.

CONCLUSION

Experimentally, alternate-day treatment with S-1 is equivalent to consecutive-day treatment in terms of RI of tumor growth, with lower toxicity.

Development history and concept of an oral anticancer agent S-1 (TS-1): its clinical usefulness and future vistas

Dushinsky et al. left a great gift to human beings with the discovery of 5-fluorouracil (5-FU). Approximately 50 years have elapsed from that discovery to the development of S-1 (TS-1^®). The concept of developing an anticancer agent that simultaneously possesses both efficacy-enhancing and adverse reaction-reducing effects could be achieved only with a three-component combination drug. S-1 is an oral anticancer agent containing two biochemical modulators for 5-FU and tegafur (FT), a metabolically activated prodrug of 5-FU. The first modulator, 5-chloro-2,4-dihydroxypyridine (CDHP), enhances the pharmacological actions of 5-FU by potently inhibiting its degradation. The second modulator, potassium oxonate (Oxo), localizing in mucosal cells of the gastrointestinal (GI) tract after oral administration, reduces the incidence of GI toxicities by suppressing the activation of 5-FU in the GI tract. Thus, S-1 combines FT, CDHP and Oxo at a molar ratio of 1:0.4:1. In 1999–2007, S-1 was approved for the treatment of the following seven cancers: gastric, head and neck, colorectal, non-small cell lung, breast, pancreatic and biliary tract cancers. ‘S-1 and low-dose cisplatin therapy’ without provoking Grade 3 non-hematologic toxicities was proposed to enhance its clinical usefulness. Furthermore, ‘alternate-day S-1 regimen’ may improve the dosing schedule for 5-FU by utilizing its strongly time-dependent mode of action; the former is characterized by the low incidences of myelotoxicity and non-hematologic toxicities (e.g. ≤Grade 1 anorexia, fatigue, stomatitis, nausea, vomiting and taste alteration). These two approaches are considered to allow long-lasting therapy with S-1.

A randomized phase II trial of adjuvant chemotherapy with uracil/tegafur and gemcitabine versus gemcitabine alone in patients with resected pancreatic cancer

BACKGROUND

There have been few randomized studies of adjuvant chemotherapy using gemcitabine (GEM) in patients with resected pancreatic cancer.

METHODS

Patients with invasive ductal pancreatic cancer who underwent radical surgery were enrolled and assigned to receive uracil/tegafur (UFT) and GEM together (GU) or GEM alone (G). GEM was administrated at a dosage of 1 g/m(2) intravenously weekly 3 of 4 weeks and UFT at a dosage of 200 mg/day orally continuously. Eligibility included resection status 0 or 1, and no previous chemo- or/and radiation therapy. The primary endpoint was disease-free survival (DFS), and secondary endpoints included overall survival (OS) and toxicity.

RESULTS

Between 2002 and 2005, 100 patients were randomized into the 2 arms of the trial (50 patients to GU and 50 to G). One patient in the G group was found to be ineligible. Baseline characteristics were well balanced between the 2 groups. With a median observation period of 21 months, the 1- and 3-year DFS rates were 50.0% and 17.7% in the GU group and 49.0% and 21.6% in the G group, respectively. The median OS was 21.2 months in the GU group and 29.8 months in the G group. Toxicity was minor and acceptable, less than grade 4 in both groups.

CONCLUSIONS

Postoperative GEM-based adjuvant chemotherapy was safe and well tolerated. However, addition of UFT with GEM did not improve DFS as compared with GEM alone. Further clinical trial resources for adjuvant chemotherapy should address other combinations and novel agents.

Adjuvant treatments for resectable hepatocellular carcinoma

Hepatocellular carcinoma often recurs even after curative resection. Although some encouraging data showing improvements in recurrence-free times have been reported with the use of intraarterial 131I-lipiodol infusion, retinoids, interferon, or immunotherapy after hepatectomy, there is no consensus regarding standard adjuvant therapy for resectable hepatocellular carcinoma. A novel target agent, sorafenib, which has recently become a standard of care for advanced disease, may also be promising in an adjuvant setting to prevent early recurrence after curative surgery. In future trials, it will be important to identify appropriate target populations for each type of adjuvant approach; that is, an agent with definitive antitumor activity for high-risk patients, and one that shows chemoprevention for low-risk patients.

Bevacizumab reduces the growth rate constants of renal carcinomas: a novel algorithm suggests early discontinuation of bevacizumab resulted in a lack of survival advantage

BACKGROUND

To hasten cancer drug development, new paradigms are needed to assess therapeutic efficacy. In a randomized phase II study in patients with renal cell carcinoma, 10 microg/kg bevacizumab (Avastin; Genentech, Inc., South San Francisco, CA) administered every 2 weeks resulted in a longer time to progression but a statistically significant difference in overall survival could not be demonstrated.

METHODS

We developed a novel two-phase equation to estimate concomitant rates of tumor regression (regression rate constant) and tumor growth (growth rate constant). This method allows us to assess therapeutic efficacy using tumor measurements gathered while a patient receives therapy in a clinical trial.

RESULTS

The growth rate constants of renal cell carcinomas were significantly lower during therapy with 10 microg/kg bevacizumab than those of tumors in patients receiving placebo. In all cohorts the tumor growth rate constants were correlated with survival. That a survival advantage was not demonstrated with bevacizumab appears to have been a result of early discontinuation of bevacizumab.

CONCLUSIONS

Single-agent bevacizumab significantly affects the growth rate constants of renal cell carcinoma. Extrapolating from the growth rate constants, we conclude that the failure to demonstrate a survival advantage in the original study was a result of premature discontinuation of bevacizumab. The mathematical model described herein has applications to many tumor types and should aid in evaluating the relative efficacies of different therapies. Quantitating tumor growth rate constants using data gathered while patients are enrolled in a clinical trial, as in the present study, may streamline and assist in drug development.

Chemotherapy for gastric cancer that recurs after adjuvant chemotherapy with S-1

We retrospectively analyzed the efficacy of chemotherapy in patients whose gastric cancer recurred after adjuvant chemotherapy with S-1. A total of 51 patients were evaluated. Twenty-one patients received S-1-containing chemotherapy as first-line treatment after recurrence [cohort A: S-1 plus cisplatin (n = 10), S-1 monotherapy (n = 7), S-1 plus irinotecan (n = 3) and S-1 plus docetaxel (n = 1)]. The other 30 patients received a non-S-1-containing regimen [cohort B: paclitaxel or docetaxel (n = 22), irinotecan plus cisplatin (n = 6) and other drugs (n = 2)]. No objective responses occurred in cohort A, while five patients achieved a partial response in cohort B (response rate, 0 versus 16%; P = 0.04). Median progression-free survival was significantly longer in cohort B than in cohort A (4.3 versus 2.3 months, P = 0.02). S-1-containing chemotherapy does not appear to be effective in patients whose gastric cancer recurs after adjuvant S-1 chemotherapy. Other chemotherapeutic agents should be evaluated in this setting.

Improved local control by surgery and paclitaxel-based chemoradiation for esophageal squamous cell carcinoma: results of a retrospective non-randomized study

BACKGROUND AND OBJECTIVES

To investigate the impact of using paclitaxel in chemoradiation on locally advanced esophageal squamous cell carcinoma (SCC) treated with or without surgery.

METHODS

Of 127 patients with AJCC stages II-III esophageal SCC undergoing definitive chemoradiation (DefCRT, n = 44) or neoadjuvant chemoradiation plus surgery (NeoCRT + S, n = 83), 57 received chemotherapy with paclitaxel and cisplatin (TP), and 70 received 5-fluorouracil and cisplatin (PF). Three-year local progression-free survival (LPFS), distant metastasis-free survival, overall survival, and prognostic factors were retrospectively analyzed.

RESULTS

The median survival was 30 months. Pathological complete response rate was 41% and 27% with TP and PF, respectively (P = 0.19). NeoCRT + S achieved significantly higher LPFS than DefCRT (71% vs. 39%, P < 0.001). Patients receiving TP had significantly higher LPFS than PF (74% vs. 48%, P = 0.04). Local control was similar between DefCRT with TP and NeoCRT + S. Distant metastasis-free survival and overall survival were not different between treatment modalities or chemotherapy regimens. In multivariate analysis, surgery (HR 0.30, P < 0.001), TP regimen (HR 0.38, P = 0.007), and mediastinal lymphadenopathy (HR 2.37, P = 0.008) were independent factors for LPFS.

CONCLUSIONS

Both surgery and the use of paclitaxel-based chemoradiation may improve local disease control. Future randomized trials should integrate paclitaxel into definitive chemoradiation.

D2 lymphadenectomy alone or with para-aortic nodal dissection for gastric cancer

BACKGROUND

Gastrectomy with D2 lymphadenectomy is the standard treatment for curable gastric cancer in eastern Asia. Whether the addition of para-aortic nodal dissection (PAND) to D2 lymphadenectomy for stage T2, T3, or T4 tumors improves survival is controversial. We conducted a randomized, controlled trial at 24 hospitals in Japan to compare D2 lymphadenectomy alone with D2 lymphadenectomy plus PAND in patients undergoing gastrectomy for curable gastric cancer.

METHODS

Between July 1995 and April 2001, 523 patients with curable stage T2b, T3, or T4 gastric cancer were randomly assigned during surgery to D2 lymphadenectomy alone (263 patients) or to D2 lymphadenectomy plus PAND (260 patients). We did not permit any adjuvant therapy before the recurrence of cancer. The primary end point was overall survival.

RESULTS

The rates of surgery-related complications among patients assigned to D2 lymphadenectomy alone and those assigned to D2 lymphadenectomy plus PAND were 20.9% and 28.1%, respectively (P=0.07). There were no significant differences between the two groups in the frequencies of anastomotic leakage, pancreatic fistula, abdominal abscess, pneumonia, or death from any cause within 30 days after surgery (the rate of death was 0.8% in each group). The median operation time was 63 minutes longer and the median blood loss was 230 ml greater in the group assigned to D2 lymphadenectomy plus PAND. The 5-year overall survival rate was 69.2% for the group assigned to D2 lymphadenectomy alone and 70.3% for the group assigned to D2 lymphadenectomy plus PAND; the hazard ratio for death was 1.03 (95% confidence interval [CI], 0.77 to 1.37; P=0.85). There were no significant differences in recurrence-free survival between the two groups; the hazard ratio for recurrence was 1.08 (95% CI, 0.83 to 1.42; P=0.56).

CONCLUSIONS

As compared with D2 lymphadenectomy alone, treatment with D2 lymphadenectomy plus PAND does not improve the survival rate in curable gastric cancer. (ClinicalTrials.gov number, NCT00149279.)

Is the addition of cisplatin to S-1 better than S-1 alone for patients with advanced gastroesophageal cancer?

The investigators of the recent phase III SPIRITS trial found that the addition of cisplatin to S-1 (a fourth generation oral fluoropyrimidine) provided a significant overall survival advantage (P = 0.04) over treatment with S-1 alone among previously untreated patients with advanced gastric cancer. In addition, the combination had an acceptable safety profile. This trial establishes a new first-line standard treatment for patients with advanced gastric cancer in Japan. Level 1 evidence for prolonged survival of patients with advanced gastroesophageal cancer has been established for docetaxel (V-325 trial) and cisplatin (SPIRITS trial) but not for S-1. Fluoropyrimidines (S-1 included) have been considered part of standard front-line therapy without the establishment of level 1 evidence for prolonging survival. The future lies in the rapid incorporation of biologic agents in combination with cytotoxics, with a continued focus on safety and convenience, and efforts to individualize therapy for each patient. Individualized therapy may be defined as the selection of optimum treatment for a specific patient on the basis of knowledge of the cancer's genetic and epigenetic alterations and the patient's genotype.

Upper gastrointestinal tumors: current status and future perspectives

Recent therapeutic developments that have provided new promising and successful approaches to the treatment of solid tumors are in large part due to the increasing understanding of their molecular biology. Despite this progress, these new therapies have provided minimal benefit in the treatment of upper gastrointestinal (GI) malignancies. Hence, the overall survival of patients with upper GI tumors remains dismal. These disappointing results are largely due to the lack of early detection strategies, inadequate medical treatments and the poor understanding of upper GI tumor biology. Clinically, the treatment paradigm has been evolving for these malignancies. Esophageal cancer is now commonly treated with preoperative chemoradiation in the USA, in both academic and community cancer centers, due to its theoretical advantages. Adjuvant chemotherapy and chemoradiation are also frequently used in patients with pancreatic cancer. Exciting prospects remain in the medical and surgical treatment of these malignancies with the inclusion of biologic agents in many protocols, newer chemotherapeutic agents (such as S-1 in the treatment of gastric cancer), and the use of minimally invasive procedures for the treatment of premalignant and, possibly, early malignant lesions of the esophagus and stomach. This review focuses on the current practice in the management of upper GI tumors and summarizes the recent advances in the field.

European Organisation of Research and Treatment of Cancer (EORTC) Gastrointestinal Group: Workshop on the role of metabolic imaging in the neoadjuvant treatment of gastrointestinal cancer

Metabolic imaging and early response assessment by positron emission tomography (PET) are gaining importance in guiding treatment of localised and metastatic gastrointestinal tumours. During a workshop organised by the European Organisation of Research and Treatment of Cancer (EORTC) Gastrointestinal Tract Cancer Group the most relevant research questions, methodological aspects and unmet clinical needs in this disease were discussed. Potential future trials were drafted. This paper reviews the lectures and discussions held during this workshop and summarises the action points for the further investigation of metabolic imaging to guide treatment in gastrointestinal tumours.

Interleukin-2 potentiation of cetuximab antitumor activity for epidermal growth factor receptor-overexpressing gastric cancer xenografts through antibody-dependent cellular cytotoxicity

Cetuximab, a chimeric monoclonal antibody to epidermal growth factor receptor (EGFR), has been proved to have clinically significant antitumor activity against advanced colorectal cancers, but its therapeutic activity for gastric cancers remains unclear. In the present study, we investigated the antitumor effect and action mechanism of cetuximab using EGFR high-expressing (MKN-28) and EGFR low-expressing (GLM-1) gastric cancer cell lines without gene amplification. Cetuximab showed neither significant growth inhibition nor induction of apoptosis in either cell line in vitro, and only slightly inhibited ligand-induced phosphorylation of protein kinase B and extracellular signal-regulated kinase in MKN-28 cells. In contrast, cetuximab significantly inhibited subcutaneous and intraperitoneal tumor growth of MKN-28 cells, but not GLM-1 cells, in nude mice. This antitumor activity was significantly enhanced and diminished in nude mice by treatment with interleukin-2 (IL-2) and antiasialo GM1 antibody, which can expand and deplete natural killer (NK) cells, respectively. Antibody-dependent cellular cytotoxicity (ADCC) of cetuximab, as measured by (51)Cr release assay, was significantly higher in MKN-28 than in GLM-1 cells. This ADCC activity was enhanced by IL-2 and reduced by heat-aggregate of human immunoglobulin G, an inhibitor for FcR-III of NK cells. These results suggest that cetuximab in combination with IL-2 shows significant antitumor activity against EGFR high-expressing gastric cancer mainly through NK cell-mediated ADCC. Combination therapy with cetuximab and IL-2 would thus offer a new potential therapeutic approach for a subset of EGFR-overexpressing gastric cancers.

Multidisciplinary management of gastric and gastroesophageal cancers

Carcinomas of the stomach and gastroesophageal junction are among the five top leading cancer types worldwide. In spite of radical surgical R0 resections being the basis of cure of gastric cancer, surgery alone provides long-term survival in only 30% of patients with advanced International Union Against Cancer (UICC) stages in Western countries because of the high risk of recurrence and metachronous metastases. However, recent large phase-III studies improved the diagnostic and therapeutic options in gastric cancers, indicating a more multidisciplinary management of the disease. Multimodal strategies combining different neoadjuvant and/or adjuvant protocols have clearly improved the gastric cancer prognosis when combined with surgery with curative intention. In particular, the perioperative (neoadjuvant, adjuvant) chemotherapy is now a well-established new standard of care for advanced tumors. Adjuvant therapy alone should be carefully discussed after surgical resection, mainly in individual patients with large lymph node positive tumors when neoadjuvant therapy could not be done. The palliative treatment options have also been remarkably improved with new chemotherapeutic agents and will further be enhanced with targeted therapies such as different monoclonal antibodies. This article reviews the most relevant literature on the multidisciplinary management of gastric and gastroesophageal cancer, and discusses future strategies to improve locoregional failures.

Surgery and adjuvant chemotherapy

It was clearly demonstrated that good local control by either radiotherapy or D2 surgery is essential to cure gastric cancer. D2 surgery can be carried out safely with a large volume of patients and can provide better survival than limited surgery. More extended surgery than D2 cannot provide better survival and causes greater morbidity; therefore, it should not be carried out as prophylactic lymphadenectomy. The effect of adjuvant treatment depends on the type of surgery. Neoadjuvant plus post-operative triplet chemotherapy, postoperative adjuvant chemoradiotherapy, and postoperative S-1 monotherapy now are the standards of care in Europe, the United States, and Japan, respectively.

Current strategies in systemic treatment of gastric cancer and cancer of the gastroesophageal junction

Gastric cancer is a major health issue and a leading cause of death worldwide. The results of standard therapy remain unsatisfactory mainly because of diagnosis at the late stage of disease. Innovative strategies such as neoadjuvant chemotherapy in locally advanced cancer have improved the outcome even in operable cases. Whether an adjuvant radiochemotherapy is of benefit after curative resection including systematic lymphadenectomy remains yet unclear. Some progress has been made in the palliative setting by introducing new substances. This review examines recent advances in the systemic treatment of gastric and gastroesophageal junction cancer.

Cancer of the esophagus and stomach

Upper gastrointestinal tumors involving the esophagus and the stomach are a serious public health problem worldwide. The West has seen a dramatic increase in the incidence of gastroesophageal cancers in the past 2 decades. Although Barrett esophagus has been well characterized, the exact pathway to developing frank malignancy remains undefined. Current treatments for locoregional disease include surgery, chemotherapy, radiation therapy, or some combination thereof. Clinical trials are currently investigating biologic agents that target signaling pathways in carcinogenesis. Whether this research translates into an improved therapeutic index remains to be seen. This review provides a comprehensive update to physicians and residents who contribute to the care of these patients. Studies in the English language were identified searching PubMed (January 1, 1980, through February 29, 2008) using the terms esophagus, gastric, carcinoma, adenocarcinoma, squamous cell, radiation, chemotherapy, surgery, esophagectomy, and targeted therapy.

The role of UFT in advanced gastric cancer

BACKGROUND

Advanced gastric cancer has a poor prognosis, with a relative 5-year survival rate of 7%-27%. Chemotherapy, which improves overall survival (OS) and quality of life, is the main treatment option. Although numerous regimens have been investigated, there is no standard treatment. Combination chemotherapy, however, is associated with a significant survival benefit compared with monotherapy and i.v. 5-fluorouracil (5-FU) is one of the most widely used agents. UFT (tegafur-uracil) has similar efficacy to continuous infusion 5-FU with improved tolerability and is more convenient for patients.

DESIGN

The efficacy and safety of UFT in the treatment of advanced gastric cancer have been demonstrated in a number of phase II studies.

RESULTS

UFT with leucovorin (folinic acid) monotherapy shows overall response rates (ORRs) of 16%-29% and median OS of 5.8 months. Combination of UFT with cisplatin, etoposide, or paclitaxel shows ORRs of 35%-51% and median OS of 8.3-10.1 months. UFT-based three-drug combinations show ORRs of 41%-57% and median OS of 8.6-15 months. UFT-based combinations have a good tolerability profile, particularly a low incidence of myelosuppression, mucositis, and hand-foot syndrome.

CONCLUSION

UFT represents a logical replacement for 5-FU in chemotherapy regimens for the treatment of advanced gastric cancer.

Phase I dose escalation study of docetaxel with a fixed dose of S-1 in combination chemotherapy for advanced gastric cancer

BACKGROUND

The primary objectives of this study were to estimate the maximum-tolerated dose (MTD) of docetaxel in combination with a fixed dose of S-1 and to determine the recommended dose (RD).

PATIENTS AND METHODS

Patients with histologically proven gastric carcinoma with metastatic or locally advanced inoperable disease were eligible. Patients received intravenous docetaxel starting at 40 mg/m(2) (dose level 1), and stepwise dose increases to 50, 60, and 70 mg/m(2) were planned for successive patient cohorts (dose levels 2, 3, and 4, respectively) over 1 h on day 1 and oral S-1 administered at a fixed dose of 40 mg/m(2) twice daily on days 1-14, both drugs every 21 days.

RESULTS

A total of 13 patients were enrolled into this trial. All three patients at dose level 3 developed dose-limiting toxicities (DLT), and this level was declared to be the MTD. Hence, level 2 (docetaxel 50 mg/m(2)) was declared to be the RD for the next study. As 9 of the 13 enrolled patients responded to treatment, the overall objective response rate was 69.2% (95% CI, 44.1-94.3%). The median time to progression was 8.38 months (range 1.44-8.51) and the overall survival duration was 9.9 months (range 0.62-11.57). The most common grade 3/4 toxicity of docetaxel plus S-1 was neutropenia, which was tolerable and manageable.

CONCLUSION

This regimen showed encouraging activity and a manageable safety profile in advanced gastric carcinoma and could be used in further randomized studies.

Current status of chemoradiotherapy for gastric cancer in Japan

Chemoradiotherapy (CRT) is the latest modality to be explored as a treatment for gastric cancer. Advances have been made in the United States with CRT as preoperative or postoperative adjuvant treatment. The rationale for preoperative or postoperative adjuvant CRT is to increase the curability of surgery or to prevent local recurrence, because standard surgery (D0 or D1) is not sufficient to control local relapse and improve survival where disease has become advanced. D2 is standard in Japan and D2 gastrectomy plus postoperative adjuvant chemotherapy with S-1 is currently standard for stage II and III cancer. Predominant recurrence patterns associated with these advanced disease stages are peritoneal dissemination and hematogenous metastasis. Local relapse or regional nodal recurrence is infrequent. CRT has been provided at only a limited number of institutions in Japan. The response to and safety of CRT for gastric cancer, in combination with various chemotherapeutic agents, are currently being studied in patients with unresectable or recurrent disease. Considering the high response rate, CRT seems to be an attractive option. In the near future, an examination will be made to ascertain whether neoadjuvant CRT in combination with extensive surgery has survival benefits in the treatment of locally advanced disease. Prior to this, a phase I/II study should be conducted in patients with unresectable or recurrent disease.

Anti-angiogenic effect of 5-Fluorouracil-based drugs against human colon cancer xenografts

In addition to the direct cytotoxic effects of chemotherapy agents on tumor cells, the anti-angiogenic activities attained by these agents by targeting proliferating endothelial cells in tumor blood vessels has attracted much research interest. In this study, we examined the antitumor activity of 5-Fluorouracil (5-FU)-based drugs (S-1 [1M tegafur, 0.4M 5-chloro-2,4-dihydroxypyridine and 1M potassium oxonate] and capecitabine) on human colorectal cancer xenografts and evaluated their anti-angiogenic effects. Both drugs showed significant antitumor activities against COL-1 xenografts at a sub-maximum tolerated dose (sub-MTD), which was lower than the maximum tolerated dose (MTD). At the sub-MTD, a significant reduction in the microvessel number and the enhancement of tumor-associated microvessel endothelial cell apoptosis was seen in xenografts treated with S-1. In addition, we found that thrombospondin-1 (TSP-1) expression, known to be a mediator of the anti-angiogenic effects of metronomic chemotherapy, was significantly up-regulated in xenograft tumor tissues and plasma in animals treated with S-1 at a sub-MTD. Capecitabine also showed a trend toward the induction of TSP-1. These results suggest that 5-FU-based drugs inhibit tumor progression through different modes of action, including cytotoxic activity derived from 5-FU and the inhibition of angiogenesis through the induction of TSP-1.