Comparison the sixth and seventh editions of the AJCC staging system for T1 gastric cancer: a long-term follow-up study of 2124 patients.

BACKGROUND/AIM: The aim of this study was to establish an appropriate TNM staging system for early gastric cancer. METHODOLOGY: We evaluated 2124 patients who had undergone gastrectomy for early gastric cancer between 1989 and 2001. RESULTS: Using the seventh edition of the American Joint Committee on Cancer (AJCC) staging system, we found no significant differences in tumor recurrence and survival between N1 and N2 cancers or between N3a and N3b cancers, whereas the survival curves for N2 and N3 cancers were quite different. Similarly, using the classification in the sixth edition of the AJCC staging system, we found no significant difference in survival between the N2 and N3 cancer groups, whereas the survival curves for N1 versus N2 or N3 cancers were quite different. CONCLUSIONS: The classifications in the sixth and seventh editions of the AJCC staging system have a limitation for T1 gastric cancer (early gastric cancer).

Phase I/II study of a combination of capecitabine, cisplatin, and intraperitoneal docetaxel (XP ID) in advanced gastric cancer patients with peritoneal metastasis.

BACKGROUND: This study was conducted to determine the recommended dose (RD) of intraperitoneal docetaxel (ID) in combination with systemic capecitabine and cisplatin (XP) and to evaluate its efficacy and safety at the RD in advanced gastric cancer (AGC) patients with peritoneal metastasis. METHODS: AGC patients with peritoneal metastasis received XP ID, which consists of 937.5 mg/m2 of capecitabine twice daily on days 1-14, 60 mg/m2 of intravenous cisplatin on day 1, and intraperitoneal docetaxel at 3 different dose levels (60, 80, or 100 mg/m2) on day 1, every 3 weeks. In the phase I study, the standard 3 + 3 method was used to determine the RD of XP ID. In the phase II study, patients received RD of XP ID. RESULTS: In the phase I study, ID 100 mg/m2 was chosen as the RD, with one dose-limiting toxicity (ileus) out of six patients. The 39 AGC patients enrolled in the phase II study received the RD of XP ID. The median progression-free survival was 11.0 months (95% CI 6.9-15.1), and median overall survival was 15.1 months (95% CI 9.1-21.1). The most frequent grade 3/4 adverse events were neutropenia (38.6%) and abdominal pain (30.8%). The incidence of abdominal pain cumulatively increased in the later treatment cycles. CONCLUSIONS: Our study indicated that XP ID was effective, with manageable toxicities, in AGC patients with peritoneal metastasis. As the cumulative incidence of abdominal pain was probably related to bowel irritation by ID, it might be necessary to modify the dose.

Appropriate gastrectomy resection margins for early gastric carcinoma.

OBJECTIVE: In Korea and Japan, early gastric cancer (EGC) accounts for >50% of all gastric cancers. Here, we propose recommendations for the optimal distance from the tumor to the resection margins when evaluating EGC. SUMMARY OF BACKGROUND DATA: There are very few guidelines regarding the distance from the EGC tumor to the resection margins. METHODS: We evaluated 2,081 patients who underwent gastrectomy for EGC between January 1989 and May 2000. We subdivided tumors according to the distance from the proximal margin: ≤ 1, >1, ≤ 10, >10, ≤ 30, or >30 mm. RESULTS: Three of five patients demonstrating distances ≤ 1 mm between the tumor and gross proximal margin were microscopically positive. No patients with gross proximal margins >1, ≤ 10, >10, or ≤ 30 mm were microscopically positive. There were no statistical differences in rates of microscopically positive margin, reresection, or reoperation between groups (P > 0.05). In addition, there were statistical differences in terms of tumor recurrence and disease-related death between groups (P > 0.05). CONCLUSIONS: When the resection margins are clear, we propose that margins >1 mm are adequate for EGC gastrectomy.

Differences in the prognosis of early gastric cancer according to sex and age.

BACKGROUND: Few studies have compared early gastric cancer (EGC) outcomes according to sex and age. METHODS: We retrospectively reviewed 2085 patients who underwent curative gastrectomy for EGC between 1989 and 2000. Prognosis and risk factors for nodal involvement were evaluated according to sex and age. RESULTS: Male sex and age were independent prognostic factors for overall survival (OS) but not relapse-free survival (RFS). In young (⩽55 years) patients, there were no significant differences in RFS and OS between men and women. However, older (>55 years) men had a poorer OS and older women had a poorer RFS. Young female patients had a higher proportion of gastric cancer-related death than young male patients. Female sex was an independent risk factor for nodal involvement in younger patients. CONCLUSIONS: Young women with EGC should be more intensively treated and monitored than other patient groups and should not be treated by endoscopic resection.

Signet ring cell type and other histologic types: differing clinical course and prognosis in T1 gastric cancer.

BACKGROUND: The behavior of early stage signet ring cell carcinoma (SRC) is controversial. The purpose of this study was to clarify the behavior of early gastric SRC. METHODS: We retrospectively analyzed data from 2,085 patients who had undergone curative gastrectomy for early gastric cancer between 1989 and 2000. Clinicopathologic outcomes and prognoses were evaluated, and we investigated whether these variables were correlated with histopathologic type. RESULTS: Patients with early gastric SRC were younger and had a greater proportion of females than other histologic types. Lymph node metastasis was the only independent prognostic factor for both mucosal and submucosal forms of SRC. Mucosal SRC had a similar rate of lymph node metastasis to poorly differentiated (PD) tubular adenocarcinoma (TUB), and a higher rate than well-differentiated (WD) or moderately differentiated (MD)-TUB. However, its submucosal form had a similar rate of lymph node metastasis to WD-TUB, and a lower rate than MD- or PD-TUB. There was no difference in tumor recurrence or disease-related death according to histopathologic type or depth of invasion. CONCLUSION: In mucosal gastric cancer, SRC has an unfavorable risk factor of lymph node metastasis than that of others and should not be considered for endoscopic resection. In submucosal gastric cancer, SRC is a more favorable risk factor of lymph node metastasis than that of other histologic types.

Gastric cancer staging at multi-detector row CT gastrography: comparison of transverse and volumetric CT scanning.

PURPOSE: To prospectively evaluate the accuracy of multi-detector row computed tomography (CT) gastrography for preoperative staging of gastric cancer, with pathologic and surgical results as the reference standard. MATERIALS AND METHODS: This study was approved by the institutional review board, and patients gave written informed consent. One hundred six patients (72 male, 34 female; mean age, 56 years) with endoscopically proved gastric cancer underwent unenhanced and contrast material-enhanced multi-detector row CT gastrography, with effervescent granules used as oral contrast material. Two experienced radiologists independently evaluated the depth of tumor invasion into the gastric wall (tumor staging), the involvement of regional lymph nodes (nodal staging), and the presence or absence of metastasis (metastatic staging) on transverse and volumetric CT images, which included images produced with multiplanar reformation and a virtual endoscopic technique. TNM staging of each tumor was compared with the pathologic and surgical results. Diagnostic accuracy in TNM staging was analyzed. RESULTS: Gastric cancer was detected in 92 (87%) of 106 study patients with transverse CT imaging and in 104 (98%) with volumetric CT imaging. The overall accuracy of the tumor staging was 77% with transverse CT imaging and 84% with volumetric CT imaging (P < .001). The overall accuracy for lymph node staging was 62% with transverse CT imaging and 64% with volumetric CT imaging (P = .057). For staging of metastases, there was no difference between transverse and volumetric CT imaging (86% for both) (P > .99). CONCLUSION: Multi-detector row CT gastrography with multiplanar reformation and virtual endoscopy, compared with transverse CT imaging, can improve the accuracy of preoperative staging of gastric cancer. This difference was significant for tumor staging but not for the staging of lymph nodes and metastases.

Effect of asymmetric stress relaxation on the polarization-dependent transmission characteristics of a CO2 laser-written long-period fiber grating.

The effect of stress-induced birefringence on polarization-dependent transmission characteristics was thoroughly investigated for a long-period fiber grating (LPFG) that was fabricated by use of a stress relaxation method with a CO2 laser. A series of two-dimensional axial stress profiles for one complete period of a LPFG was measured with an optical tomographic measurement technique. We found that the asymmetry in the stress distribution of the cladding was much larger than in the core of the LPFG. The splitting of polarization-dependent loss peaks in the optical transmission spectrum was calculated based on the measured asymmetric stress profiles and was compared with an experimental result.