Longterm control of advanced and recurrent gastric cancer (ARGC) by S-1

S-1-based vs non-S-1-based chemotherapy in advanced gastric cancer: A meta-analysis

AIM: To assess the efficacy and tolerability of S-1-based vs non-S-1-based chemotherapy in advanced gastric cancer (AGC).

METHODS: We extracted reported endpoints, including overall survival (OS), progression-free survival (PFS), time-to-treatment failure (TTF), objective response rate (ORR) and adverse effects, from randomized controlled trials identified in PubMed, the Cochrane library, Science Direct, EMBASE and American Society of Clinical Oncology meetings. Stata software was used to calculate the pooled values.

RESULTS: Seven randomized controlled trials involving 2176 patients were included in this meta-analysis. Compared to non-S-1-based regimens, the use of S-1-based regimens were associated with an increase in ORR (RR = 1.300; 95%CI: 1.028-1.645); OS (HR = 0.89; 95%CI: 0.81-0.99; P = 0.025), TTF (HR = 0.83; 95%CI: 0.75-0.92; P = 0.000), and a lower risk of febrile neutropenia (RR = 0.225; P = 0.000) and stomatitis (RR = 0.230; P = 0.032). OS, PFS and TTF were prolonged, especially in the Asian population. In subgroup analysis, statistically significant increases in ORR (RR = 1.454; P = 0.029), OS (HR = 0.895; P = 0.041) and TTF (HR = 0.832; P = 0.000) were found when S-1-based chemotherapy was compared to 5-fluorouracil (5-FU)-based chemotherapy. The incidence of leukopenia (RR = 0.584; P = 0.002) and stomatitis (RR = 0.230; P = 0.032) was higher in the 5-FU-based arm. S-1-based regimens had no advantage in ORR, OS, PFS, TTF and grade 3 or 4 adverse events over capecitabine-based regimens.

CONCLUSION: S-1-based chemotherapy may be a good choice for AGC because of longer survival times, better tolerance and more convenient use.

Consecutive daily low-dose S-1 adjuvant chemotherapy after radical treatment for squamous cell carcinoma in head and neck cancer

CONCLUSION

Consecutive daily low-dose S-1 therapy was less toxic and its efficacy was not inferior to the conventional administration schedule. Consecutive daily low-dose S-1 chemotherapy appears to be a treatment option for patients in whom it is difficult to continue the conventional administration schedule of S-1 due to adverse events.

OBJECTIVE

To evaluate the safety and efficacy of consecutive daily low-dose S-1 therapy in an adjuvant setting.

METHODS

This study investigated 52 patients with absence of local residual tumor, lymph node metastasis or distant metastasis after radical treatment for advanced head and neck squamous cell carcinoma. After receiving informed consent from patients, half of the usual dose of S-1 was administered daily for 2 years. The safety, feasibility, and efficacy of this approach were evaluated.

RESULTS

Hematologic toxicity was seen in 51 of 52 patients (98.1%), but grade 3 hematologic toxicity was found in only 2 patients (3.8%). Nonhematologic toxicity was observed in 15 patients (28.8%) and all were grade 1. Forty-three patients (82.7%) were able to complete the chemotherapy for 2 years without dose reduction. The 3-year disease-free survival rate and 3-year survival rate were 82.6% and 94.0%, respectively.

Significance of volume-reduction surgery for far-advanced gastric cancer during treatment with novel anticancer agents

BACKGROUND

We retrospectively assessed the survival benefit of novel anticancer agents (NACA) after volume-reduction surgery for far-advanced gastric cancer (FAGC).

METHODS

From 1995 to 2005, 41 patients with FAGC underwent chemotherapy after volume-reduction surgery. Those treated since 2000 who received NACA were referred to as group A, and those treated before 2000, who received anticancer agents other than NACA, were referred to as group B. In addition, 21 patients with unresectable gastric cancer treated since 2000 who received NACA were referred to as group C. We investigated the significance of volume-reduction surgery during treatment with NACA.

RESULTS

The median survival time (MST) was significantly prolonged in group A (626 days) compared to group B (364 days; P = 0.0156). Multivariate analysis showed that having one noncurative factor (NCF), and the use of NACA, were factors that contributed to survival time. Comparison between the subgroup of group A that had one NCF and the subgroup that had two or more NCFs revealed MSTs of 700 days and 180 days, respectively, with a significantly longer MST among the patients with one NCF (P = 0.0021). In addition, no difference from the MST of 333 days in group C was seen among the group A patients with two or more NCFs.

CONCLUSION

The postoperative survival time of patients with one NCF was prolonged by the advent of NACA, but no significant prolongation was observed in the patients with two or more NCFs.

S-1: a promising new oral fluoropyrimidine derivative

S-1 is an oral fluoropyrimidine that is designed to improve the antitumor activity of 5-fluorouracil (5-FU) concomitantly with an intent to reduce its toxicity. S-1 consists of tegafur, a prodrug of 5-FU combined with two 5-FU biochemical modulators:5-chloro-2,4-dihydroxypyridine (gimeracil or CDHP), a competitive inhibitor of dihydropyrimidine dehydrogenase and oteracil potassium which inhibits phosphorylation of 5-FU in the gastrointestinal tract decreasing serious gastrointestinal toxicities,including nausea, vomiting, stomatitis and diarrhea. Being an oral agent, S-1 offers convenience of administration and prevents complications of central venous access such as infection, thrombosis and bleeding. S-1 has shown efficacy in both gastrointestinal as well non-gastrointestinal malignancies. The authors review the current literature and provide their expert opinion on the incorporation of S-1 in the treatment of solid malignancies [corrected].

Multiple and metachronous esophageal intramural metastases from a gastric adenocarcinoma

Esophageal squamous cell carcinoma is often accompanied by intramural metastases, and it has been reported to carry a poor prognosis. Intramural metastasis from gastric cancer to the esophageal wall, however, has rarely been reported. We herein report a rare case of a 46-year-old man with an elevated esophageal lesion, resembling a 0-IIa-type esophageal cancer, which was discovered 13 months after a total gastrectomy performed for gastric cancer. The esophageal tumor, resected by endoscopic mucosal resection (EMR), was an adenocarcinoma with the same histology as the previously resected primary gastric cancer, and it showed massive lymphatic permeation. Soon after the EMR, other similar lesions emerged on the esophageal wall. We therefore considered the esophageal tumor to be a systemic expansion of the primary gastric cancer, and we administered the anticancer drug, S-1. Esophageal intramural metastases from a gastric cancer imply a systemic expansion of the gastric cancer, and portend a poor prognosis.

Upregulation of Enzymes Metabolizing 5-Fluorouracil in Colorectal Cancer

BACKGROUND

The purpose of this study was to compare the activities of various enzymes, participating in the metabolism of 5-fluorouracil, between colorectal cancer and nontumor tissues and to investigate the association of the enzyme activities with clinicopathological backgrounds.

METHODS

Activities of seven enzymes involved in nucleic acid metabolism--orotate phosphoribosyltransferase (OPRT), ribonucleotide reductase (RNR), thymidylate synthase, dihydropyrimidine dehydrogenase, thymidine phosphorylase, uridine phosphorylase and thymidine kinase (TK)--were measured in tumor and nontumor tissues from 28 patients who were operated on for colorectal cancers.

RESULTS

OPRT, thymidylate synthase, RNR, thymidine phosphorylase, uridine phosphorylase and thymidine kinase activities were significantly higher in tumor areas than in nontumor areas. OPRT showed the highest T/N ratio (the ratio of each enzyme activity in tumor areas to that in nontumor areas). The T/N ratio of RNR activity showed a tendency to be associated with lymph node metastasis and Dukes classification.

CONCLUSION

The results suggest that OPRT is a main enzyme participating in the phosphorylation of 5-fluorouracil and has an important role in tumor growth. The T/N ratio of RNR may be predictive of tumor progression.

The efficacy of gastrectomy for large gastric cancer

BACKGROUND

Large gastric cancer (LGC) is frequently associated with extended disease, and the role of surgical resection has been debated. We investigated the efficacy of surgical treatment for LGC.

METHODS

The size of LGC was defined as 8 cm or greater. Four hundred and fifteen patients with LGC who underwent gastrectomy were included. The clinicopathological features, the status of the residual tumor, the incidence and patterns of relapse, and the survival were analyzed.

RESULTS

Macroscopically, diffuse-type tumors were dominant (60%). The numbers of patients with tumors of T3 or greater, lymph node involvement, and peritoneal metastases were 356 (86%), 359 (87%), and 126 (30%), respectively. One hundred and eighty-eight patients (45%) underwent incomplete tumor resection (R2). The R2/R0 (no residual tumor) ratio was greater than 1 in patients with type 4 tumors and N1 or greater metastasis and in those with type 3 tumors and N2 or greater metastasis. In contrast, T2, type 2, and type 5 tumors were more likely to be completely resected. The 5-year survival for all 415 patients was 26%. The survival rates were inversely related to the tumor type, size, and lymph node metastasis. In the 216 patients with R0, the 5-year survivals of those with pN (International Union Against Cancer [UICC] classification) 0, 1, 2, and 3 were 66%, 56%, 36%, and 5%, respectively (P = 0.001). In 96 of these 216 patients (44%) the tumor recurred, and peritoneal metastasis was the most frequent mode of recurrence (48%). By Cox's proportional hazard model, the tumor size was an independent prognostic factor.

CONCLUSION

The chance of achieving R0 resection for LGC is low, except for T2, type 2, or type 5 tumors. Primary resection should be avoided for other types of LGC.