Adjuvant therapy for gastric carcinoma patients in the past 15 years

Adenoviral oncolytic suicide gene therapy for a peritoneal dissemination model of gastric cancer in mice

BACKGROUND

Peritoneal dissemination of gastric cancer is often refractory to systemic therapies. Although adenoviral gene therapy has been reported to be a potentially useful therapeutic modality, the adenovirus itself has a dose-limiting toxicity. A novel system was constructed using adenoviral oncolytic suicide gene therapy targeting carcinoembryonic antigen (CEA), and its therapeutic effect and the possibility to reduce the total viral dose while still preserving the antitumor effect were assessed.

METHODS

Three types of adenoviruses were prepared for this novel system: (A) Ad/CEA-Cre, (B) Ad/lox-CD::UPRT for a Cre/loxP system, and (C) Ad/CEA-E1 for conditionally replicating adenovirus. The antitumor effect of the oncolytic suicide gene therapy (A + B + C) was then evaluated in vitro. Mice bearing peritoneal dissemination of human gastric cancer were treated with either this system (A + B + C) or with a tenfold viral dose of suicide gene therapy (A + B). The adverse effects in terms of hepatotoxicity were then evaluated between the two groups.

RESULTS

The current system (A + B + C) demonstrated significantly better cytotoxic effect for CEA-producing cell lines than did suicide gene therapy (A + B) at the same viral dose in vitro. The effect of oncolytic suicide gene therapy was almost equal to that of the tenfold viral dose of suicide gene therapy in vivo. The hepatotoxicity of the two treated groups was also found to be equivalent.

CONCLUSION

It was possible to reduce the total adenoviral dose of oncolytic suicide gene therapy while still preserving the antitumor effect.

Gene therapy using ets-1 transcription factor decoy for peritoneal dissemination of gastric cancer

The ets-1 transcription factor plays an important role in cell proliferation, differentiation, apoptosis and tissue remodeling. Aberrant ets-1 expression correlates with aggressive tumor behavior and poorer prognosis in patients with various malignancies. This study evaluated the efficacy of double-stranded decoy oligonucleotides targeting ets-1-binding cis elements for the suppression of ets-1 in treatment of a peritoneal dissemination model of gastric cancer. In vitro, MTT assay was performed to evaluate the effect of the ets-1 decoy on cell growth. Electrophoretic mobility shift assay (EMSA) was performed to determine ets-1 activity. In vivo, the effect of the ets-1 decoy was investigated in the peritoneal dissemination nude mice model. Disseminated nodules were analyzed immunohistochemically. Ets-1 decoy, but not scrambled decoy, significantly inhibited cell growth in 2 gastric cancer cell lines, which showed overexpression of ets-1 protein by inhibiting the binding activity of ets-1. In the peritoneal dissemination model, the ets-1 decoy significantly suppressed the disseminated nodules, and tended to prolong the survival rate. PCNA index, microvessel density and VEGF expression were also reduced in peritoneal tumors treated with ets-1 decoy. Intraperitoneal injection of ets-1 decoy inhibited peritoneal dissemination of gastric cancer in a nude mice model. The results indicate that the decoy strategy for ets-1 offers a promising therapy for patients with incurable peritoneal dissemination of gastric cancer, most of which show overexpression of ets-1 protein.

The effectiveness of intravenous 5-fluorouracil-containing chemotherapy after curative resection for gastric carcinoma: A systematic review of published randomized controlled trials

This is a review of randomized controlled trials of intravenous 5-flurorouracil (5-FU)-containing chemotherapy after curative resection versus surgery alone in patients with gastric carcinoma to determine the impact on survival rate, safety and economics. Data sources were the Cochrane Library (2006, Issue 2), Pub-Medline and Chinese Biomedical Database. We included 22 randomized controlled trials comparing 4501 patients. Intravenous 5-FU-containing chemotherapy after curative resection had a slightly significant improvement in 3-, 5- and 7-year overall survival rate (OR 1.49, 1.41 and 1.32). No benefit of postoperative disease-free survival rate was induced by 5-FU-containing chemotherapy. Sensitivity analysis was restricted to trials with the highest methodological quality, and the result was similar when the studies with Jadad score less than 3' were excluded. Subgroup analyses found borderline improved overall survival rate in both Western and Eastern countries but the statistical significance was stronger in the Eastern subset. The combinations of 5-FU plus mitomycin C, 5-FU plus cytosine arabinoside and 5-FU plus adriamycin or epidoxorubicin induced potentially more improvement of 3- and 5-year overall survival rates. Severe toxicities were reported in 1629 patients from 15 included trials, and hematological and gastrointestinal toxicities were the most remarkable side effects, around 5%-15% respectively. The chemotherapy-related overall mortality was 1.1%. No trials mentioned cost-effectiveness analysis. Although the results provide some evidence of a beneficial effect of adjuvant chemotherapy with 5-FU-containing regimens, they are inconclusive due to the limitations of methodological quality of including randomized controlled trials. Large scale randomized controlled trials with a positive result are still mandatory before postoperative chemotherapy are recommended.

Adjuvant treatment of high-risk, radically resected gastric cancer patients with 5-fluorouracil, leucovorin, cisplatin, and epidoxorubicin in a randomized controlled trial

BACKGROUND

Promising findings obtained using a weekly regimen of 5-fluorouracil (5-FU), epidoxorubicin, leucovorin (LV), and cisplatin (PELFw) to treat locally advanced and metastatic gastric cancer prompted the Italian Group for the Study of Digestive Tract Cancer (GISCAD) to investigate the efficacy of this regimen as adjuvant treatment for high-risk radically resected gastric cancer patients.

METHODS

From January 1998 to January 2003, 400 gastric cancer patients at high risk for recurrence including patients with serosal invasion (stage pT3 N0) and/or lymph node metastasis (stage pT2 or pT3 N1, N2, or N3), were enrolled in a trial of adjuvant chemotherapies; 201 patients were randomly assigned to receive the PELFw regimen, consisting of eight weekly administrations of cisplatin (40 mg/m2), LV (250 mg/m2), epidoxorubicin (35 mg/m2), 5-FU (500 mg/m2), and glutathione (1.5 g/m2) with the support of filgrastim, and 196 patients were assigned to a regimen consisting of six monthly administrations of a 5-day course of 5-FU (375 mg/m2 daily) and LV (20 mg/m2 daily, 5-FU/LV). Disease-free and overall survival were estimated and compared between arms using hazard ratios (HRs) and Kaplan-Meier estimates. All statistical tests were two-sided.

RESULTS

The 5-year survival rates were 52% in the PELFw arm and 50% in the 5-FU/LV arm. Compared with the 5-FU/LV regimen, the PELFw regimen did not reduce the risk of death (HR = 0.95, 95% confidence interval [CI] = 0.70 to 1.29) or relapse (HR = 0.98, 95% CI = 0.75 to 1.29). Less than 10% of patients in either arm experienced a grade 3 or 4 toxic episode. Neutropenia (occurring more often in the PELFw arm) and diarrhea and mucositis (more prevalent in the 5-FU/LV arm) were the most common serious side effects. Nevertheless, only 19 patients (9.4%) completed the treatment in the PELFw arm and 85 (43%) patients completed the treatment in the 5-FU/LV arm.

CONCLUSIONS

Our study found no benefit from an intensive weekly chemotherapy in gastric cancer. The extent of toxicity experienced by the patients in the adjuvant setting suggests that, in gastric cancer, chemotherapy may be more safely administered preoperatively.

Molecular markers for gastric adenocarcinoma: an update

Gastric cancer is the second most common cancer worldwide. Treatment of localized gastric cancer relies primarily on surgical intervention, although growing evidence suggests that the addition of chemoradiation may improve disease-free intervals and overall survival. In this regard, the current high rates of recurrence and subsequent poor survival have prompted an ever-increasing use of multimodal strategies, even for early-stage disease. However, these therapies are often limited by debilitating toxicities and varying degrees of response efficacy. As a result, pharmacogenomics, the study of specific genetic and molecular signatures that may be predictive of treatment outcomes, has gained considerable interest. For example, studies have demonstrated that the expression of enzymes involved in the metabolism or conjugation of commonly used chemotherapy agents, such as fluoropyrimidines and cisplatin, can serve as surrogate markers predictive of chemotherapy response. Polymorphisms in the genes encoding these enzymes have also been identified and may further account for altered expression patterns, resulting in varied clinical responses. Future work is necessary to further refine the list of molecular genetic markers and to identify novel markers for prognostic and predictive purposes. Technologies such as microarray analysis may be useful in identifying new molecular genetic markers, and further work may determine whether these markers can be employed to help stratify patients into different multimodal treatment regimens.

In vitro and in vivo evidence of metallopanstimulin-1 in gastric cancer progression and tumorigenicity

PURPOSE

The metallopanstimulin-1 (MPS-1) gene is a growth factor-inducible gene, which is highly expressed in many human cancers and may be involved in the progression towards tumor malignancy. However, it is unclear whether MPS-1 plays any role in gastric cancer development or progression. Our studies were designed to clarify the MPS-1 expression pattern and to explore its potential role in gastric cancer.

EXPERIMENTAL DESIGN

The expression pattern of MPS-1 was determined in primary gastric cancer specimens and gastric cancer cell lines via immunohistochemistry and Western blotting. To investigate the functional significance of MPS-1 expression, three small interfering RNA (siRNA) expression plasmids were constructed and transfected into gastric cancer cell line SGC7901. The stable cell lines transfected with the siRNA targeting MPS-1 mRNA plasmids were selected and the biological features of these cells were examined.

RESULTS

MPS-1 was overexpressed in 86% of the gastric cancer tissues and all gastric cancer cells. In addition, MPS-1 expression was significantly increased and corresponded with the tumor-node-metastasis clinical stage, and was significantly higher in the late stage (P < 0.01). The MPS-1 expression level was significantly decreased in the transfected cells with MPS-1-specific siRNA expression plasmid pRNAT-133. Furthermore, the stable transfected cancer cells exhibited an increase in the incidence of spontaneous apoptosis and a decrease in growth ability and tumorigenicity in nude mice.

CONCLUSIONS

These results provide strong evidence that MPS-1 plays an important role in gastric cancer cell proliferation and development, and suggests that MPS-1 is a promising target for gastric cancer treatment.

Pilot study of postoperative adjuvant chemoradiation for advanced gastric cancer: Adjuvant 5-FU/cisplatin and chemoradiation with capecitabine

AIM: To evaluate the efficacy and toxicity of postoperative chemoradiation using FP chemotherapy and oral capecitabine during radiation for advanced gastric cancer following curative resection.

METHODS: Thirty-one patients who had underwent a potentially curative resection for Stage III and IV (M0) gastric cancer were enrolled. Therapy consists of one cycle of FP (continuous infusion of 5-FU 1000 mg/m² on d 1 to 5 and cisplatin 60 mg/m² on d 1) followed by 4500 cGy (180 cGy/d) with capecitabine (1650 mg/m² daily throughout radiotherapy). Four wk after completion of the radiotherapy, patients received three additional cycles of FP every three wk. The median follow-up duration was 22.2 mo.

RESULTS: The 3-year disease free and overall survival in this study were 82.7% and 83.4%, respectively. Four patients (12.9%) showed relapse during follow-up. Eight patients did not complete all planned adjuvant therapy. Grade 3/4 toxicities included neutropenia in 50.2%, anemia in 12.9%, thrombocytopenia in 3.2% and nausea/vomiting in 3.2%. Neither grade 3/4 hand foot syndrome nor treatment related febrile neutropenia or death were observed.

CONCLUSION: These preliminary results suggest that this postoperative adjuvant chemoradiation regimen of FP before and after capecitabine and concurrent radiotherapy appears well tolerated and offers a comparable toxicity profile to the chemoradiation regimen utilized in INT-0116. This treatment modality allowed successful loco-regional control rate and 3-year overall survival.

An observational study suggesting clinical benefit for adjuvant postoperative chemoradiation in a population of over 500 cases after gastric resection with D2 nodal dissection for adenocarcinoma of the stomach

PURPOSE

The role of adjuvant chemoradiotherapy (CRT) in D2-resected gastric-cancer patients has not been defined yet. We investigated the effect of postoperative chemoradiotherapy on the relapse rate and survival rate of patients with D2-resected gastric cancer.

METHODS AND MATERIALS

From August 1995 to April 2001, 544 patients received postoperative CRT after curative D2 resection. During the same period of time, 446 patients received surgery without further adjuvant treatment. The adjuvant CRT consisted of 400 mg/m2 of fluorouracil plus 20 mg/m2 of leucovorin for 5 days, followed by 4,500 cGy of radiotherapy for 5 weeks, with fluorouracil and leucovorin on the first 4 and the last 3 days of radiotherapy. Two 5-day cycles of fluorouracil and leucovorin were given 4 weeks after the completion of radiotherapy.

RESULTS

The median duration of overall survival was significantly longer in the CRT group than in the comparison group (95.3 months vs. 62.6 months), which corresponds to a hazard ratio for death of 0.80 (p = 0.0200) or a reduction of 20% in the risk of death in the CRT group. The 5-year survival rates were consistently longer in the CRT group at Stages II, IIIA, IIIB, and IV than those in the comparison group. The CRT was associated with increases in the median duration of relapse-free survival (75.6 months vs. 52.7 months; hazard ratio for relapse, 0.80, p = 0.0160).

CONCLUSION

Our results highly suggest that the postoperative chemoradiotherapy in D2-resected gastric-cancer patients can prolong survival and decrease recurrence.

Multidrug resistance-associated protein (MRP1) gene is strongly expressed in gastric carcinomas. Analysis by immunohistochemistry and real-time quantitative RT-PCR

AIMS

To assess MRP1 protein and MRP1 mRNA levels in gastric carcinomas and in non-neoplastic mucosa remote from the tumours. MRP1 gene expression may play a role in the complex pattern of chemoresistance present in gastric carcinomas.

METHODS AND RESULTS

A total of 57 carcinomas and respective gastric tissues were included for immunohistochemical assessment with the anti-MRP1 monoclonal antibodies MRPr1 and QCRL-1. Of these, 35 tumour and gastric mucosa tissues were also assessed by real-time quantitative reverse transcriptase-polymerase chain reaction. Medium or high MRP1 protein expression was detected in 89% and 77% of carcinomas and in 96% and 93% of non-neoplastic gastric mucosa by MRPr1and QCRL-1, respectively. No difference in MRP1 mRNA levels was detected between carcinomas and non-neoplastic gastric mucosa tissues in 77% of the patients. A significant correlation was found between MRP1 mRNA level and protein expression detected in carcinomas related to non-neoplastic gastric mucosa, although they were non-concordant in 29% of the patients.

CONCLUSIONS

MRP1 gene is usually expressed in most gastric carcinomas and does not differ substantially from that observed in non-neoplastic gastric mucosa remote from the tumour. However, a decrease in MRP1 gene expression is found in some carcinomas. For accurate assessment of changes in MRP1 expression between tumour and normal tissues both protein and mRNA detection are necessary.

Adjuvant chemotherapy with 5-fluorouracil and cisplatin compared with surgery alone for gastric cancer: 7-year results of the FFCD randomized phase III trial (8801)

BACKGROUND

The aim of this study was to evaluate the efficacy of adjuvant chemotherapy after resection for gastric cancer in a randomized controlled trial.

PATIENTS AND METHODS

After curative resection, stage II-III-IVM0 gastric cancer patients were randomly assigned to postoperative chemotherapy or surgery alone. 5-Fluorouracil (5-FU) 800 mg/m(2) daily (5-day continuous infusion) was initiated before day 14 after resection. One month later, four 5-day cycles of 5-FU (1 g/m(2) per day) plus cisplatin (100 mg/m(2) on day 2) were administered every 4 weeks.

RESULTS

The study was closed prematurely after enrollment of 260 patients (79.7% N+), owing to poor accrual. At 97.8 months median follow-up, 5- and 7-year overall survival were 41.9% and 34.9% in the control group versus 46.6% and 44.6% in the chemotherapy group (P=0.22). Cox model hazard ratios were 0.74 [95% confidence interval (CI) 0.54-1.02; P=0.063] for death and 0.70 (95% CI 0.51-0.97; P=0.032) for recurrence. An invaded/removed lymph nodes ratio >0.3 was the main independent poor prognostic factor identified by multivariate analysis (P=0.0001). Because of toxicity, only 48.8% of patients received more than 80% of the planned dose.

CONCLUSION

There was no statistically significant survival benefit with this toxic cisplatin-based adjuvant chemotherapy, but a risk reduction in recurrence was observed.

Audit of postoperative chemoradiotherapy as adjuvant therapy for resected gastroesophageal adenocarcinoma: an Australian multicentre experience

BACKGROUND

Improved disease free and overall survivals were seen in curatively resected patients with gastric and gastroesophageal adenocarcinoma treated with the Intergroup 0116 (INT 0116) protocol of postoperative adjuvant chemoradiotherapy compared to surgery alone. This protocol has not been widely adopted in Australian centres because of perceived risks of toxicity.

METHODS

We reviewed the case records from 45 consecutive patients treated between May 1998 and August 2003 with the INT 0116 protocol and variations at five Australian institutions. The median age was 61.5 years (range 38-79). Twenty-nine patients had gastric and 12 had gastroesophageal junction primaries. All patients had attempted curative resection, however, seven had involved microscopic margins (R1 resection). Thirty-five had regional node involvement and none had evidence of distant metastasis.

RESULTS

The overall National Cancer Institute-Common Toxicity Criteria (NCI-CTC) version 2.0 grade 3 and grade 4 toxicity rates for all patients were 37.8% and 4.4%, respectively. There were no treatment related deaths. Gastrointestinal grade 3 toxicity was observed in 20% of patients, while haematologic grade 3 and 4 toxicity was observed in 17.8%. Toxicities experienced led to chemotherapy dose reductions in 22 patients and dose delay in 11 patients. Seven patients had a delay in radiotherapy and two did not proceed with radiotherapy. At a median follow up of 16 months (range 5-35) from surgery, 28 patients have relapsed (six with local recurrence alone) with 22 deaths occurring, all but one caused by cancer.

CONCLUSION

The INT 0116 protocol is a safe and feasible schedule in a multicentre setting with an acceptable rate of toxicity and is an appropriate adjuvant treatment option for high-risk resected gastroesophageal adenocarcinoma.

Application of molecular diagnosis for detection of peritoneal micrometastasis and evaluation of preoperative chemotherapy in advanced gastric carcinoma

BACKGROUND

In advanced gastric cancer, peritoneal recurrence is the main cause of death after curative surgical resection. The aim of this report was to describe a novel approach for quantitative genetic diagnosis using peritoneal lavage for the identification of patients at high risk for peritoneal recurrence and for evaluation of the clinical response to intraperitoneal chemotherapy in advanced gastric cancer.

METHODS

Nineteen patients with advanced gastric cancer who underwent staging laparoscopy and intraperitoneal chemotherapy before surgical resection or systemic chemotherapy between June 1999 and September 2001 were enrolled in this study. All peritoneal lavage specimens, collected at both staging laparoscopy and gastrectomy, were subjected to real-time quantitative genetic diagnosis.

RESULTS

The reverse transcriptase polymerase chain reaction (RT-PCR) values decreased in 8 cases, stabilized as negative in 5, and increased in 6 during therapy. Patients whose RT-PCR values diminished and were ultimately negative survived except for one, and all but one patient whose values increased during treatment died of recurrence.

CONCLUSIONS

Quantitative evaluation of genetic changes can provide accurate, useful information on the effects of preoperative intra-abdominal chemotherapy and overall prognosis for patients with advanced gastric cancer.

Gastric Adenocarcinoma

Adenocarcinoma of the stomach is advanced enough in some patients to preclude curative treatment, but many gastric cancer patients have what appears to be localized disease that is amenable to surgical resection, which is the only truly effective treatment. Long-term results of what appear to be "curative resections" are relatively poor, however, and new management tools such as sentinel lymph node biopsy, recently promising adjunctive therapies (such as radiochemotherapy), and the organization of the order of treatment combinations do require further study with an eye to improving outcomes. However, there appears to be little hope for a dramatic improvement in treatment results from these innovations for patients with established gastric cancer. Fortunately, gastric cancer in the United States has gone from being the number one cause of cancer death in our population 50 years ago to that of being the number eight cause of cancer death at this time. This intriguing major decrease in the incidence of this disease must be considered secondary to one or more changes in our own environment that we hope will be exploitable in the future. As with cancers of all types and in all sites, a prevention strategy may prove more effective than the treatment strategies that are outlined here. The management strategies outlined are hopefully only temporary ones until we are able to develop a better handle on primary prevention.

Highly specific marker genes for detecting minimal gastric cancer cells in cytology negative peritoneal washings

Peritoneal wash cytology plays a pivotal role in the decision for gastric cancer treatment because advanced gastric cancer often turns out incurable with peritoneal metastasis. Molecular detection of minimal cancer cells from peritoneal washings may overcome the sensitivity boundary of conventional cytology and contribute to the prediction of the disease outcome. To select marker candidates out of ten thousands of genes, we performed microarray analyses in 12 gastric cell lines and 8 peritoneal washings of early stage cases. With 40 candidates selected by the above expression profiling, RT-PCR in 16 representative peritoneal wash samples was performed to identify genes specific to cytology positive samples. The finally selected five genes, CK20, FABP1, MUC2, TFF1, and TFF2, were then evaluated for their utility as a marker for minimal residual disease in 99 peritoneal wash samples. Nested RT-PCR using the five genes showed positive results highly specific to incurable cases (91-100%). With a high specificity, the combination of these five genes succeeded in identifying 6 out of 20 (30%) additional patients with all types of early recurrence that could not be predicted by the conventional method. The six newly identified recurrences included four non-peritoneal ones, showing that RT-PCR using the five genes without a real-time quantitative PCR technique contributes to the detection of minimal residual disease.

Gastric cancer: advances in adjuvant and adjunct therapy

Patients with gastric carcinoma remain at high risk for local and systemic relapses, even after a successful surgery (R0 resection). To reduce the rate of relapse and increase cure rates, several clinical adjuvant trials have been reported. Only a few studies have reported positive results and most have failed to demonstrate any benefit for the treated patients. The trials with positive results from chemotherapy or chemoimmunotherapy have not gained global acceptance. The Intergroup 0116 trial has gained acceptance in North America, but it has not been accepted globally. In North America, where gastric surgery is often less than optimal, the Intergroup 0116 trial has provided evidence of benefit in overall survival time and time-to-cancer progression for patients treated with postoperative chemoradiotherapy. This trial recruited 556 patients with resected gastric cancer from stage IB through IV and an R0 resection was mandatory for registration. The results of this trial have spurred many other studies and controversies. In our opinion, all of the patients in the West who have had a curatively resected node-positive gastric carcinoma (R0 resection) should be offered an option of receiving postoperative chemoradiotherapy.

Experimental study to evaluate the usefulness of S-1 in a model of peritoneal dissemination of gastric cancer

BACKGROUND

Favorable results have been reported for the novel oral anticancer agent S-1 (TS-1) in clinical studies of advanced gastric cancer with peritoneal dissemination. In the present study we assessed its pharmacokinetics, inhibitory effects, and effect on survival time in an animal model.

METHODS

A model of peritoneal dissemination was created by intraperitoneally implanting 4-week-old female BALBc nu/nu mice with the human gastric cancer cell line MKN-45 after transfection with a fluorescent protein-expressing vector. Pharmacokinetics were investigated by measuring intratumor, peritoneal lining, and blood concentrations after the administration of S-1 and fluorouracil (5-FU). The effect of S-1 on survival time was also assessed, by administration once daily to seven animals per group, starting on day 7 after implantation, and survival time was compared with that of an untreated control group. The inhibitory effect of S-1 on peritoneal dissemination was evaluated by killing mice at the start of administration, and 1 and 3 weeks after the start of administration, and examining them for the presence of peritoneal dissemination under a fluorescence stereomicroscope.

RESULTS

Maintenance of high 5-FU concentrations in the intraperitoneal tumors was confirmed in the S-1 group, and survival time was prolonged without any decrease in oral food intake or body weight.

CONCLUSION

Assessment in a model of peritoneal dissemination of gastric cancer showed that the novel oral anticancer agent S-1 was effective against peritoneal dissemination, and that it improved the survival rate.

Postoperative chemoradiotherapy for gastric cancer

BACKGROUND

We report the results of postoperative chemoradiotherapy after curative resection in gastric cancer patients.

PATIENTS AND METHODS

Patients with gastric cancer staged IB to IV(M0) were treated with chemoradiotherapy after curative resection with extensive (D2) lymph node dissection. Nodal metastases were observed in 261 (90%) patients. The chemotherapy consisted of fluorouracil 400 mg/m(2) plus leucovorin 20 mg/m(2) for 5 days, followed by 4500 cGy of radiotherapy for 5 weeks with fluorouracil and leucovorin on the first 4 days and the last 3 days of radiotherapy. Two 5-day cycles of chemotherapy were given 4 weeks after the completion of radiotherapy.

RESULTS

Of 290 patients accrued, 229 (79%) patients completed chemoradiotherapy as planned. With a median follow-up of 49 months, 114 (34%) patients have relapsed: 33 (29%) locoregional relapses, 76 (67%) peritoneal relapses and 41 (36%) distant metastases. The 5-year overall and relapse-free survivals were 60% and 57%, respectively. Tolerance was acceptable, the main toxicity being neutropenia.

CONCLUSIONS

This postoperative chemoradiotherapy after curative resection of gastric cancer was feasible, with acceptable toxicities. Whether this adjuvant therapy in gastric cancer patients that have undergone a D2 lymph node dissection impacts on survival or reduces the incidence of relapses remains to be studied.

Chemoradiation for resectable gastric cancer

The incidence of gastric cancer has been declining in recent years, however, the disease continues to be a worldwide public health problem. About two thirds of patients with gastric cancer undergo surgical resection with curative intent. R0 resection--complete local-regional tumour removal with negative resection margins--is the only curative modality. The optimum extent of lymph-node dissection (D1 vs D2) is controversial. Disease relapse, both local and distant, is common and the 5-year survival rate is disappointing. Adjuvant chemotherapy has been studied extensively in this setting but an effective regimen has not yet been identified. A recent intergroup study has shown that postoperative chemoradiation is effective in improving both disease-free survival (3-year, 48% vs 31%, p<0.001) and overall survival (3-year, 50% vs 41%, p=0.005) compared with surgery alone. Preoperative radiation as a single adjuvant therapy has also yielded improvements in local-regional control, disease-free survival, and overall survival compared with surgery alone. Preoperative chemotherapy or chemoradiation has been accepted to have a theoretical advantage over postoperative therapy and has now been shown to be a feasible option. Its efficacy, however, remains to be tested.

Prevention of peritoneal metastasis of human gastric cancer cells in nude mice by S-1, a novel oral derivative of 5-Fluorouracil

OBJECTIVE

Recent clinical trials have suggested that oral administration of a new anti-cancer agent, S-1, seems a promising therapy for advanced gastric cancer. In this study, we assessed the efficacy of S-1 against peritoneal dissemination of gastric cancer in a newly developed animal model and investigated the efficacy of S-1 from a pharmacokinetic angle.

METHODS

Human gastric cancer cells (MKN-45) were injected into the peritoneal cavity of nude mice. The cancer cells were transduced using an enhanced green fluorescent protein (EGFP)-expressing plasmid vector, enabling micrometastatic foci to be accurately assessed with a high level of detection sensitivity. To investigate pharmacokinetics, the concentration of 5-FU was determined in tumor, peritoneum and plasma.

RESULTS

Fourteen and 21 days after intraperitoneal injection, a significant difference in the number of fluorescent foci was observed between the control group and the S-1 group (p = 0.02 and p = 0.0024, respectively. The therapeutic effect of S-1 was significantly greater than that of 5-FU. Furthermore, S-1 treatment greatly improved the survival time and cachexia. The area under the curve of 5-FU in tumor was higher than in the peritoneum and plasma.

CONCLUSION

Oral S-1 is a promising chemotherapy for peritoneal dissemination of gastric cancer.

Neoadjuvant radiochemotherapy for locally advanced gastric cancer: a phase I-II study

BACKGROUND

To study in a phase I-II trial the maximum tolerated dose, the toxicity, and the tolerance of adding radiotherapy to systemic chemotherapy administered preoperatively in patients with locoregionally advanced gastric adenocarcinoma.

PATIENTS AND METHODS

Patients with adenocarcinoma of the stomach (T(3)(-)(4)N(any) or T(any)N+), performance status </=1, normal hematological, hepatic and renal functions received two cycles of cisplatin 100 mg/m(2) on day 1, 5-FU 800 mg/m(2) on days 1 to 4 and leucovorin 60 mg b.i.d. on days 1 to 4 q3w, concomitantly with radiation therapy escalated in three dose tiers (31.2, 38.4 and 45.6 Gy).

RESULTS

Nineteen patients were accrued and 18 completed neoadjuvant therapy. Major toxicity consisted of grade 3/4 leucopenia and mucositis in 89% and 36% of the patients, respectively. Only one episode of febrile neutropenia was recorded. Dose level number 2 (38.4 Gy) with the chemotherapy given q4w is the recommended dose level. All patients were subsequently operated and no fatalities occurred. Pathological assessment showed one complete and eight partial responses. Two- and 3-year relapse-free survival rates were 57% and 50%, respectively. Only one patient relapsed locally. The peritoneum was the most frequent site of relapse.

CONCLUSIONS

This neoadjuvant therapeutic program is relatively well tolerated, does not seem to increase the operative risk, and might increase the locoregional control of the disease. The frequency of peritoneal involvement in relapsing patients underscores the need for a more effective systemic treatment.

Adjuvant intraperitoneal chemotherapy with cisplatinum, mitoxantrone, 5-fluorouracil, and calcium folinate in patients with gastric cancer: a phase II study

Gastric carcinoma remains one of the leading causes of cancer-related death in the world. Clinical studies have revealed that approximately two thirds of the patients seek treatment for early recurrence within the abdominal cavity. The aim of this phase II study was to evaluate the toxicity, feasibility, and efficacy of adjuvant intraperitoneal chemotherapy (IPCT) with cisplatin, mitoxantrone, 5-fluorouracil (5-FU), and folinic acid in patients with stage II-III gastric cancer. Patients with stage II and III gastric cancer aged between 15 and 70 years, after curative resection, with adequate liver, renal, and cardiac function were included in the study. The chemotherapy regimen consisted of cisplatin 60 mg/m2, mitoxantrone 12 mg/m2, 5-FU 600 mg/m2, and folinic acid 60 mg/m2, delivered intraperitoneally, diluted in 2 l normal saline. Intraperitoneal fluid was not drained. Each course of IPCT was repeated every 4 weeks for a total 6 cycles. Thirty-nine patients were enrolled in the study. Twenty-eight of the 39 patients (71.8%) completed six courses of the planned schedule. One patient (2.6%) died after a fourth cycle of IPCT from an undetermined reason. The major nonhematologic toxicity from IPCT was grade I-III nausea and/or vomiting experienced by 27 patients (69.2%). Twenty-four (61.5%) patients reported abdominal discomfort. Median follow-up was 23 (range: 3-105) months. Twenty-five patients (64.1%) were dead. Median disease-free survival and overall survival were 12 (CI 95%; 8.3-15.7 months) and 19 months (CI 95%; 10.5-27.5 months), respectively. The cumulative 5-year disease-free survival and overall survival were 24.7% and 30.7%, respectively. The regimen was generally associated with acceptable toxicity. However, adjuvant IPCT has similar survival rates in comparison to no adjuvant treatment; thus, it cannot be currently recommended outside the context of a clinical trial.

Differential gene expression profiles of gastric cancer cells established from primary tumour and malignant ascites

Advanced gastric cancer is often accompanied by metastasis to the peritoneum, resulting in a high mortality rate. Mechanisms involved in gastric cancer metastasis have not been fully clarified because metastasis involves multiple steps and requires a combination of altered expressions of many different genes. Thus, independent analysis of any single gene would be insufficient to understand all of the aspects of gastric cancer peritoneal dissemination. In this study, we performed a global analysis of the differential gene expression of a gastric cancer cell line established from a primary main tumour (SNU-1) and of other cell lines established from the metastasis to the peritoneal cavity (SNU-5, SNU-16, SNU-620, KATO-III and GT3TKB). The application of a high-density cDNA microarray method made it possible to analyse the expression of approximately 21 168 genes. Our examinations of SNU-5, SNU-16, SNU-620, KATO-III and GT3TKB showed that 24 genes were up-regulated and 17 genes down-regulated besides expression sequence tags. The analysis revealed the following altered expression such as: (a) up-regulation of CD44 (cell adhesion), keratins 7, 8, and 14 (epitherial marker), aldehyde dehydrogenase (drug metabolism), CD9 and IP3 receptor type3 (signal transduction); (b) down-regulation of IL2 receptor gamma, IL4-Stat (immune response), p27 (cell cycle) and integrin beta4 (adhesion) in gastric cancer cells from malignant ascites. We then analysed eight gastric cancer cell lines with Northern blot and observed preferential up-regulation and down-regulation of these selected genes in cells prone to peritoneal dissemination. Reverse transcriptase-polymerase chain reaction confirmed that several genes selected by DNA microarray were also overexpressed in clinical samples of malignant ascites. It is therefore considered that these genes may be related to the peritoneal dissemination of gastric cancers. The results of this global gene expression analysis of gastric cancer cells with peritoneal dissemination, promise to provide a new insight into the study of human gastric cancer peritoneal dissemination.

A phase III randomized trial of 5-fluorouracil, doxorubicin, and mitomycin C versus 5-fluorouracil and mitomycin C versus 5-fluorouracil alone in curatively resected gastric cancer

BACKGROUND

A phase III single-center randomized trial was performed in order to determine whether the addition of mitomycin C (MMC) and/or doxorubicin to 5-fluorouracil (5-FU) as adjuvant chemotherapy could influence survival in patients with curatively resected gastric cancer.

PATIENTS AND METHODS

A total of 416 patients who had undergone curative resection for stage IB-IIIB gastric adenocarcinoma were stratified according to the stage and type of surgery, and then randomized to receive one of the three chemotherapy regimens, 5-FU alone (F) or 5-FU and MMC (FM) or 5-FU, doxorubicin and MMC (FAM) within 5 weeks after surgery.

RESULTS

Of 416 patients registered, 395 (133 in F, 131 in FM and 131 in FAM) were assessable. Median follow-up duration was 91 months. Five-year overall survival rates were 67.2% for F, 67.0% for FM and 66.7% for FAM (P = 0.97). Five-year disease-free survival rates were 62.1% for F, 63.3% for FM and 62.5% for FAM (P = 0.83). Hematological toxicities were more frequent in the FM and FAM groups, whereas stomatitis was more common in the F group.

CONCLUSIONS

Compared with adjuvant 5-FU alone, the addition of MMC and/or doxorubicin to 5-FU did not influence survival in patients with resected gastric cancer.

Recent developments in the treatment of gastric carcinoma

Surgery remains the mainstay for the curative treatment of gastric carcinoma. However, despite adequate surgery, survival remains poor. The use of adjuvant chemotherapy and radiotherapy has been examined in multiple previous clinical trials without convincing evidence of efficacy. However, recently, a large randomized controlled Intergroup trial, INT 116, demonstrated a survival advantage with chemoradiotherapy following curative surgery for gastric cancer. This review discusses the merits of the Intergroup trial and the ways in which it should affect the treatment of gastric cancer in the United States. INT 116 provides a foundation on which we can build to improve the care of patients with gastric cancer. With the evaluation of potentially better chemotherapeutic agents and the advent of molecularly directed therapy, there is increasing hope for improving the care of patients with gastric carcinoma.

Adjuvant and preoperative chemotherapy for gastric cancer

Gastric cancer is the second most frequently diagnosed malignancy worldwide, and the risk of relapse remains high in the majority of patients undergoing resection. Attempts to reduce this risk and prolong survival have led to numerous adjuvant chemotherapy trials that either had no benefit for patients or occasionally had controversial results. The recently reported Intergroup 0116 trial shows conclusive evidence of survival benefit for patients treated with postoperative chemoradiotherapy. In this Intergroup trial, which involves over 600 patients, a regimen of postoperative chemotherapy plus chemoradiotherapy was shown to prolong overall and disease-free survival in gastric cancer patients with stage IB through IV disease following a curative (R0) resection. This approach should be considered the standard of care in patients with gastric cancer who have undergone curative resection. Preoperative chemotherapy shows promise in downstaging tumors and increasing the rate of curative resection, but randomized trials are needed to assess survival benefits. Efforts to combine existing treatment modalities and new agents with novel mechanisms of action hold promise for the future.

Adjuvant chemotherapy in gastric cancer: 5-year results of a randomised study by the Italian Trials in Medical Oncology (ITMO) Group

BACKGROUND

The aim of this study was to determine the efficacy of the EAP regimen (etoposide, adriamycin and cisplatin) followed by the Machover schedule (fluorouracil and folinic acid) given as adjuvant treatment to patients with poor prognostic factors (N+ or T3/4).

PATIENTS AND METHODS

Before randomisation, the subjects were stratified on the basis of node involvement (N+ or N-) and the time from surgery to randomisation (< or = 21 days or > 22 days). The surgical procedures for sub-total or total gastrectomy with D2 dissection were standardised among the participating centres.

RESULTS

Between December 1992 and December 1997, 274 patients were enrolled: 137 in the treatment arm and 137 in the control arm. The majority of the patients (90%) were N+. After a median follow up of 66 months (range 2-83), the 5-year overall survival (OS) was 52% in the treatment arm and 48% in the control arm [hazard ratio (HR) 0.93; 95% confidence interval (CI) 0.65-1.34]; the 5-year disease-free survival (DFS) was 49% and 44%, respectively (HR: 0.83; 95% CI 0.59-1.17). Among the patients with N-/N+ (1-6), the 5-year OS was 61% in the treatment group and 60% in the control group; in those with N+ (1-6), it was 42% and 22%. The treatment was completed by 87% of patients. Drug-related grade 3/4 WHO toxicities included leukopenia (21%), nausea and vomiting (14%), mucositis (9%), neutropenia (3%) and thrombocytopenia (2%). There were two deaths due to sepsis.

CONCLUSIONS

Although our results are not statistically significant, there was a limited relative risk reduction in the patients receiving adjuvant therapy (17% in DFS and 7% in OS). The data suggest that D2 surgery may have a favourable impact on OS.

Immunohistochemically detected micrometastases of the lymph nodes in patients with gastric carcinoma

BACKGROUND

Lymph node status is a major determinant of disease recurrence after patients undergo curative resection for gastric carcinoma. A proportion of patients without lymph node metastasis develop systemic recurrences. Recent studies in a range of solid tumors have found a high incidence of micrometastases in the regional lymph nodes of patients with apparently negative lymph nodes. In patients with breast and colorectal carcinoma, the presence of micrometastases has been associated with a poorer prognosis. In patients with gastric carcinoma, the significance of micrometastases in lymph nodes remains controversial. Most published reports on this subject suffer from the problems of small sample size and selection bias.

METHODS

One hundred seven patients with pathologic T2N0M0 (tumor invades muscularis propria or subserosa [T2], no regional lymph node metastasis [N0], and no distant metastasis [M0]; pT2N0M0) gastric carcinoma who underwent gastric resection between 1984 and 1990 at the National Cancer Center Hospital were studied. Two consecutive sections were newly prepared from each lymph node for hematoxylin and eosin staining and immunohistochemical staining (IHC) with antibody against cytokeratin. Associations between clinicopathologic factors and the presence of micrometastases as well as micrometastases and survival were sought.

RESULTS

Micrometastases were identified in 38 of 107 patients (35.5%) and in 87 of 4484 lymph nodes (1.94%) by IHC. The incidence of micrometastases was significantly higher in patients with infiltrative tumors than in patients with expansive, growing tumors (P = 0.02). Other clinicopathologic findings had no statistically significant correlation with the incidence of micrometastases. The 5-year survival rates of patients with and without micrometastases were 94% and 89%, respectively. Similarly, the 10-year survival rates were 79% and 74%, respectively. The survival curves of patients with or without micrometastasis were nearly superimposed (P = 0.86).

CONCLUSIONS

The presence of immunohistochemically detected micrometastases in the regional lymph nodes did not affect the survival of Japanese patients with pT2N0M0 gastric carcinoma who had undergone gastrectomy with D2 lymph node dissection.

Proximal Compared with Distal Gastric Cancer: Multivariate Analysis of Prognostic Factors

The major determinants of the poor prognosis of the patients with proximal-third gastric cancer (proximal gastric cancer or PGC) when compared with that of patients with more distally located gastric tumors (distal gastric cancer or DGC) rely both on the more advanced age and tumor stage at the moment of clinical presentation and on the higher postoperative mortality for PGC patients. We reviewed hospital records of 707 patients with gastric cancer (187 with PGC and 520 with DGC) observed during the period 1981 through 1996 at the same surgical unit. Demographic and pathological data, type of treatment, and hospital morbidity and mortality rates were recorded. Univariate and multivariate survival analysis was used to calculate the 5-year survival probabilities with respect to the following clinical and pathological variables: age, sex, gross appearance according to Borrmann classification, histological type according to Lauren, stage of the disease, tumor location, and type of treatment. PGC was associated with more advanced tumor stage ( P < 0.0001), older age ( P = 0.039), and higher necessity of extended surgery ( P < 0.0001) when compared with DGC. Hospital mortality was 9.6 and 5 per cent in PGC and DGC patients respectively ( P = 0.033). Overall 5-year survival was 17.7 and 36.4 per cent in PGC and DGC patients ( P < 0.0001): 35.9 versus 57.6% ( P = 0.0001) and 3.7 versus 7.6 per cent ( P = 0.03) after radical and palliative surgery respectively. At multivariate survival analysis proximal location was found to be independently associated ( P = 0.0007) with poor survival. The multivariate model shows the proximal location as an independent predictor of lesser favorable outcome in gastric cancer. The major determinants of the poor prognosis of PGC with respect to DGC rely both on the more advanced age and tumor stage at the moment of clinical presentation and on the higher postoperative morbidity for PGC patients.

Schedule-dependent combined sensitivity testing of anti-cancer agents in human gastric carcinoma cell lines

The efficacy of combination chemotherapy for gastric carcinoma has been unsatisfactory, although the prognosis of advanced and recurrent disease has improved with the introduction of cisplatin (CDDP). This study examines the effect of the anti-cancer therapies CDDP, doxorubicin (ADM) and etoposide (VP-16) on the cell cycle and their cytotoxicity against two gastric carcinoma cell lines: MKN-28 (well differentiated) and MKN-45 (poorly differentiated). The treatments have different cytocidal mechanisms, and they were studied in dual combinations. For all combinations studied, cytotoxicity against MKN-45 was higher than against MKN-28. For ADM plus CDDP, or ADM plus VP-16, cytotoxicity was higher in patients pretreated with ADM than other regimens. The highest anti-tumour activity against both cell lines was obtained with ADM followed by CDDP (we have obtained good clinical results with this regimen). Schedule-dependent combined sensitivity testing of anti-cancer agents will be useful for the clinical application of therapies.

Early postoperative intraperitoneal chemotherapy with mitomycin C, 5-fluorouracil and cisplatin for advanced gastric cancer

OBJECTIVE

The long-term survival of patients who undergo surgery for stage IV gastric cancer is poor, due to metastatic spread of the tumor. Intraperitoneal chemotherapy (IPT) as a possible treatment for peritoneal dissemination has been investigated in a number of different tumors. The aim of this study was to investigate the toxicity and impact of early postoperative IPT on the survival of patients with advanced gastric cancer.

METHODS

Between 1993 and 1997, a total of 91 patients with stage IV gastric cancer who underwent potentially curative or palliative resection received intraperitoneal mitomycin C before closure of the abdominal wound. 5-Fluorouracil and cisplatin were administered intraperitoneally on postoperative days 1-4, and this was repeated at 4-week intervals.

RESULTS

All patients received a median of 3 IPT perfusions. There were 24 (26.4%) postoperative complications and 1 (1.1%) mortality. The most frequent hematologic toxicity (grade 3-4) was leukopenia. The major nonhematologic toxicities (grade 3-4) were emesis and nephrotoxicity. After a median follow-up period of 26 months, 14 patients remain alive without evidence of recurrence, whereas 75 patients died due to recurrence or progression of disease. The median survival period for all 91 patients was 15.4 months. When survival according to the residual tumor was analyzed, median survival was 36.0 months in the R0 (curative resection) group, 20.6 months in the R1 group (margins of resected specimens showing microscopic residual tumor or diameter of each residual tumor less than 3 mm) and 9.0 months in the R2 group (macroscopic residual tumor larger than 3 mm) (p < 0.001).

CONCLUSIONS

IPT was found to be safe, and it appears to improve the prognosis in patients with minimal residual tumors. However, complete cytoreductive surgery is mandatory for achieving the beneficial effect of IPT.

Clinical utility of CEA, CA 19-9, and CA 72-4 in the follow-up of patients with resectable gastric cancer

BACKGROUND

The aim of this longitudinal study was to evaluate the effectiveness of the serum tumor markers CEA, CA 19-9, and CA 72-4 in the early diagnosis of recurrence of gastric cancer.

METHODS

One hundred and thirty-three patients who had undergone potentially curative surgery were considered. Serum samples were obtained preoperatively, 1 week after surgery, and at every follow-up examination. Mean follow-up time for the entire patient population was 41 +/- 33 months, and 71 +/- 27 months for patients classified as disease-free.

RESULTS

Preoperative positivity was 16% for CEA, 35% for CA 19-9, and 20% for CA 72-4. Recurrence of disease was found in 75 patients (56%). Marker sensitivity in recurrent cases was 44% for CEA, 56% for CA 19-9, and 51% for CA 72-4; the combined use of the three markers increased sensitivity to 87%, which reached 100% in patients with positive preoperative levels. Marker specificity, evaluated in 58 disease-free patients, was 79% for CEA, 74% for CA 19-9, and 97% for CA 72-4.

CONCLUSIONS

The combined assay of CEA, CA 19-9, and CA 72-4 may be useful for early diagnosis of recurrence of gastric cancer; however, only CA 72-4 positivity should be considered a specific predictor of tumor recurrence.

Adjuvant therapy for gastric cancer: a reality at last

Gastric cancer remains a significant healthcare problem throughout the world and is usually diagnosed at a fairly advanced stage in the West. Despite complete resection of the primary tumor, most patients eventually experience a relapse and die of recurrent disease. Extended surgery has not been shown to improve survival in Western studies. There have been a large number of adjuvant chemotherapy trials over the past several decades, most with negative results. More recently, there is hope for improving these dismal results with a meta-analysis showing a benefit for adjuvant chemotherapy and a large randomized trial, INT-0116, which has just reported a significant survival advantage with combined chemoradiation. These results make adjuvant therapy for completely resected gastric carcinoma the new standard of care, except in the uncommon setting of early intramucosal cancers.

Gastric cancer

Gastric adenocarcinoma is the most common malignancy of the upper gastrointestinal tract. During the past two decades it has migrated toward the gastroesophageal junction. Gastroesophageal reflux and obesity may play a role. Recent research suggests that a number of biologic and molecular differences exist in patients with gastric cancer. Further investigation in these areas may help in predicting outcome and directing therapy. Gastric cancer is not a curable condition when metastases are present. However, postoperative chemotherapy plus chemoradiotherapy, in the Intergroup trial 0116, prolonged the overall and disease-free survival rates of patients after a curative (R0) resection. It should be considered the new standard of care in patients with gastric cancer who have undergone curative resection with stage Ib-IV disease. Preoperative therapy strategies may increase the likelihood of R0 resection and remain an area of active investigation. Finally, development of more active agents is needed for the treatment of metastatic tumors.