Tadashi Anan

Thymidine phosphorylase mRNA expression may be a predictor of response to post‑operative adjuvant chemotherapy with S‑1 in patients with stage III colorectal cancer

The aim of the present study was to investigate markers in surgically resected specimens of colorectal cancer that can be used to predict the response to chemotherapy. The mRNA expression levels of enzymes involved in 5-fluorouracil (5-FU) metabolism and folate metabolism were measured in formalin-fixed, paraffin-embedded tumor sections obtained from the primary tumors of 54 patients with resected stage II or III colorectal cancer who received S-1 for one year. The 5-FU metabolizing enzymes studied were thymidylate synthase, dihydropyrimidine dehydrogenase and thymidine phosphorylase (TP). The folate metabolizing enzymes studied were folypolyglutamate synthetase, γ-glutamyl hydrolase and dihydrofolate reductase. The associations between the mRNA expression levels of these enzymes and clinical variables were investigated. Tumors were classified as exhibiting high or low expression as compared with the median mRNA expression level of each metabolizing enzyme defined as the cutoff value. The associations between the high and low expression levels of each enzyme and disease-free survival (DFS) were analyzed with the use of Kaplan-Meier curves and the log-rank test. DFS was not significantly associated with the relative mRNA expression level of any metabolizing enzyme in the study group as a whole, but there was a trend toward longer DFS in patients with high TP expression (P=0.066). In patients with stage III colorectal cancer, high TP expression was associated with significantly improved outcomes compared with low TP expression (P=0.039). These results indicate that the mRNA expression of TP, a metabolizing enzyme of 5-FU, is a significant predictor of response to post-operative chemotherapy with S-1 in patients with stage III colorectal cancer.

A comparison of laparoscopic energy devices on charges in thermal power after application to porcine mesentery.

Introduction: Advances in energy devices have played a major role in the rapid expansion of laparoscopic surgery. However, complications due to these energy devices are occasionally reported, and if the characteristics of these devices are not well understood, serious complications may occur. This study evaluated various typical energy devices and measured temperature rises in the adjacent tissue and in the devices themselves. Equipment and Methods: We used the following 7 types of energy devices: AutoSonix (AU), SonoSurg (SS), Harmonic Scalpel (HS), LigaSure Atlas (LA), LigaSure Dolphin Tip (LD), monopolar diathermy (Mono), and bipolar scissors (Bi). Laparoscopy was performed under general anesthesia in pigs, and the mesentery was dissected using each energy device. Tissue temperature at a distance of 1 mm from the energy device blade before and after dissection was measured. Temperature of the device blade both before and after dissection, time required for dissection, and interval until the temperature fell to 100°C, 75°C, and 50°C were documented. Results: Temperature of the surrounding tissue using each device rose the most with the Mono (50.5±8.0°C) and the least with the HS in full mode (6.2±0.7°C). Device temperature itself rose the highest with the AU in full mode (318.2±49.6°C), and the least with the Bi (61.9±4.8°C). All ultrasonic coagulation and cutting devices (AU, SS, and HS) had device temperatures increase up to ≥100°C, and even at 8 seconds after completing dissection, temperatures remained at ≥100°C. Conclusions: Because the adjacent tissue temperature peaked with the Mono, cautious use near the intestine and blood vessels is necessary. In addition, the active blades of all ultrasonic coagulation and cutting devices, regardless of model, developed high temperatures exceeding 100°C. Therefore, an adequate cooling period after using these devices is therefore necessary between applications.

Blood transfusion requirement for gastric cancer surgery: Reasonable preparation for transfusion in the comprehensive health insurance system

We investigated the necessity of preparation for blood transfusion in gastric cancer surgery to save costs for blood typing, antibody screening, cross-matching, and disposal of the blood product. The subjects of the study were 52 patients who underwent gastric cancer surgery at our department between 2000 and 2004. The requirement for blood transfusion during surgery was investigated in terms of patient characteristics, hemoglobin before surgery, and performance status as well as treatment regimen. Furthermore, economic effects were investigated when typing and screening (T&S) were performed instead of typing and cross-matching (T&X). Of 9 patients who received blood transfusion, 8 had gastric cancer of stage IIIB or higher, or underwent combined resection. Blood transfusion was not used in surgery for patients with early gastric cancer. The volumes of blood prepared, lost, and disposed of in 28 patients who underwent T&X were 831.3+/-249.4, 219.3+/-228.5 and 600+/-333.1 ml, respectively, whereas the blood loss in 24 patients who underwent T&S was 161.1+/-95.6 ml; this difference had a major economic effect. The practice of T&S for patients undergoing gastric surgery in the absence of combined resection for early gastric cancer seems to be a safe and cost-effective practice that abrogates disposal of blood in hospital management.