Tumor Size Improves the Accuracy of the Prognostic Prediction of Lymph Node-Negative Gastric Cancer.

BACKGROUND: Tumor size has been regarded as the "T" stage of many solid tumors because of its effect on prognosis. However, the prognostic impact of tumor size in gastric cancer (GC) is still controversial. MATERIALS AND METHODS: A total of 436 patients with curatively resected GC and those without lymph node metastasis in our center were retrospectively enrolled. The appropriate cutoff points for tumor size were determined. Potential prognostic factors were analyzed. In addition, a pathological tumor-size (pTS) classification system was proposed to evaluate the superiority of its prognostic prediction of node-negative GC patients compared with that of the pT staging system. RESULTS: The ideal cutoff points for tumor size were 4 and 8 cm. In the multivariate analysis, tumor size was identified as an independent prognostic factor for node-negative GC patients after surgery, as was pT stage. The pTS classification was found to be more appropriate for predicting the overall survival of node-negative GC patients after curative surgery than pT stage, and the -2 log-likelihood of the pTS classification (1680.782) was smaller than the value of pT (1695.239). CONCLUSIONS: As an independent prognostic factor, tumor size should be incorporated into the pT staging system to enhance the accuracy of the prognostic prediction of node-negative GC patients.

Elevated preoperative plasma D-dimer dose not adversely affect survival of gastric cancer after gastrectomy with curative intent: A propensity score analysis.

OBJECTIVE: Elevated plasma D-dimer has been reported to be associated with advanced tumor stage and poor survival in several types of malignancies. The purpose of this study was to assess the potential impact of preoperative plasma D-dimer level (PDL) on overall survival (OS) of gastric cancer (GC) patients undergoing curative surgery by applying propensity score analysis. METHODS: A total of 1,025 curatively resected GC patients in Tianjin Medical University Cancer Institute & Hospital were enrolled. Patients were categorized into two groups based on preoperative PDL: the elevated group (EG) and the normal group (NG). To overcome bias due to the different distribution of covariates for the two groups, a one-to-one match was applied using propensity score analysis, after matching, prognostic factors were analyzed. RESULTS: In analysis for the whole study series, patients in the EG were more likely to have a larger proportion of tumor size ≥5 cm (67.5% vs. 55.8%, P=0.006), elder mean age (64.0±10.8 years vs. 60.5±11.6 years, P<0.001) and advanced tumor (T), node (N), and TNM stage. Patients with elevated PDL demonstrated a significantly lower 5-year OS than those with normal PDL (27.0%vs. 42.6%, P<0.001), however, the PDL was not an independent prognostic factor for OS in multivariate analysis [hazard ratio: 1.13, 95% confidence interval (95% CI): 0.92-1.39, P=0.236]. After matching, 163 patients in the EG and 163 patients in the NG had the same characteristics. The 5-year OS rate for patients in the EG was 27.0% compared with 25.8% for those in the NG (P=0.809, log-rank). CONCLUSIONS: The poor prognosis of GC patients with elevated preoperative PDL was due to the advanced tumor stage and elder age rather than the elevated D-dimer itself.

In vitro and in vivo evaluation of osteogenesis and antibacterial activity of MgGa alloys.

MgGa alloys are considered highly potential biodegradable materials, owing to its good mechanical properties and appropriate corrosion resistance. However, it is still far from application due to the lack of biological evaluation. In the present study, biocompatibility, osteogenesis and antibacterial activity of extruded Mg-xGa (x = 1 and 5 wt%) alloys were investigated by in vitro cell culture experiments and in vivo implantation. The cell adhesion and proliferation of osteoblast precursor cells (MC3T3-E1) showed the excellent cytocompatibility of Mg-1Ga and poor cytocompatibility of Mg-5Ga. The osteogenic activity was evaluated and revealed that Ga3+ in the Mg-1Ga extract had the ability to enhance osteogenic differentiation through the facilitation of its early stages. In vivo studies in a rat femoral condyle model revealed that both Mg-1Ga and Mg-5Ga significantly promoted new bone formation without causing any adverse effects. Mg-5Ga exhibited a much higher corrosion rate in vivo than Mg-1Ga. Its osteogenic activity was better due to the rapid release of Mg2+ and Ga3+, but this caused premature structural integrity loss. Mg-1Ga and Mg-5Ga released Ga3+ to inhibit E. coli and S. aureus, with antibacterial rate increasing with Ga content. Our studies demonstrate that Mg-Ga alloys have the potential to be used as osteogenic and antibacterial implant materials. STATEMENT OF SIGNIFICANCE: This study evaluates the biocompatibility, osteogenesis, and antibacterial activity of Mg-Ga alloys, which are promising biodegradable materials for medical applications. The study finds that Mg-1Ga exhibits excellent cytocompatibility and promotes osteogenic differentiation, facilitating the early stages of osteoblast precursor cell development. In vivo studies in a rat femoral condyle model reveal that Mg-1Ga and Mg-5Ga significantly promote new bone formation without causing any adverse effects. The antibacterial activity of both alloys is evaluated against E. coli and S. aureus, with the inhibition rate increasing with Ga content. These findings suggest that Mg-Ga alloys have the potential to serve as osteogenic and antibacterial implant materials, providing significant insights into the development of novel biomedical implants.

Current status of extended 'D2 plus' lymphadenectomy in advanced gastric cancer.

The extent of lymph node (LN) dissection has been a topic of interest in gastric cancer (GC) surgery. D2 lymphadenectomy is considered the standard surgical procedure for most resectable advanced GC cases. The value and indications of more extended lymphadenectomy than D2 remain unclear. Currently, the controversial stations beyond the D2 range are mainly focused on no. 14v, no. 16a2/b1 and no. 13 LN stations. The metastatic rate of no. 14v LN is relatively high in advanced distal GC, particularly in patients with suspicious no. 6 LN metastasis. D2 plus no. 14v LN dissection may be attributed to improved survival outcomes for patients with obvious no. 6 LN metastasis. Although GC with para-aortic lymph node (PALN) metastases is considered an M1 disease beyond surgical cure, patients with limited PALN metastases may benefit from the treatment strategy of adjuvant chemotherapy followed by D2 plus no. 16a2-b1 LN dissection. In addition, D2 plus no. 13 LN dissection may be an option in a potentially curative gastrectomy for GC with duodenal invasion. The present review discusses the current status and future perspectives of D2 plus lymphadenectomy.

Tumor size improves the accuracy of the prognostic prediction of T4a stage colon cancer.

The aim of this study was to evaluate the potential impact of tumor size on the long-term outcome of colon cancer (CC) patients after curative surgery. A total of 782 curatively resected T4a stage CC patients without distant metastasis were enrolled. Patients were categorized into 2 groups according to the best threshold of tumor size: larger group (LG) and smaller group (SG). Propensity score matching was used to adjust for the differences in baseline characteristics. The ideal cutoff point of tumor size was 5 cm. In the multivariate analysis for the whole study series, tumor size was an independent prognostic factor. Patients in the LG had significant lower 5-year overall survival (OS) and relapse-free survival (RFS) rates (OS: 63.5% versus 75.2%, P < 0.001; RFS: 59.5% versus 72.4%, P < 0.001) than those in the SG. After matching, patients in the LG still demonstrated significant lower 5-year OS and RFS rates than those in the SG. The modified tumor-size-node-metastasis (mTSNM) staging system including tumor size was found to be more appropriate for predicting the OS and RFS of T4a stage CC than TNM stage, and the -2log likelihood of the mTSNM staging system was smaller than the value of TNM stage. In conclusion, tumor size was an independent prognostic factor for OS and RFS. We maintain that tumor size should be incorporated into the staging system to enhance the accuracy of the prognostic prediction of T4a stage CC patients.

Impact of extranodal tumor deposits on prognosis and N stage in gastric cancer.

BACKGROUND: Extranodal tumor deposits have been reported to be associated with a poor prognosis in many malignancies and are also included in the tumor, node, and metastasis staging system for colorectal cancer. METHODS: We reviewed retrospectively a total of 2,344 gastric cancer patients who underwent gastrectomy with curative intent at the Tianjin Medical University Cancer Institute and Hospital (Hexi District, Tianjin, China) and the First Affiliated Hospital of Hainan Medical University (Longhua District, Haikou, China). Patients were categorized into 2 groups based on extranodal tumor deposit status: a positive group, including those with extranodal tumor deposits, and a negative group composed of those with no extranodal tumor deposits. Clinicopathologic factors were correlated with extranodal tumor deposits, and their individual prognoses were analyzed. In addition, a pathologically modified node classification system was proposed by incorporating the extranodal tumor deposit status into the 8th ed of the N staging system. The superiority of prognostic prediction between the modified node classification and node stage was compared. RESULTS: A total of 645 (27.5%) patients had extranodal tumor deposits. The presence of extranodal tumor deposits was associated with a larger tumor size, Borrmann type III and IV, a deeper depth of invasion, and an advanced node stage. In the multivariate analysis, extranodal tumor deposits were an independent prognostic factor for gastric cancer patients after curative resection. Gastric cancer patients with extranodal tumor deposits demonstrated a lesser 5-year overall survival than those with no extranodal tumor deposits (31.9% vs 61.4%, P < .001). With the strata analysis, statistically significant prognostic differences between the two groups were only observed in patients at the N0-N2 stage. The modified node classification was found to be more appropriate for predicting the overall survival of gastric cancer patients after curative resection than node stage, and the -2 log likelihood of the modified node classification (16,042.890) was smaller than the value of node stage (16,150.811). CONCLUSION: Extranodal tumor deposits in gastric cancer patients indicate aggressive characteristics and a poorer prognosis of gastric cancer. We maintain that extranodal tumor deposits should be incorporated into the N staging system to enhance the accuracy of the prognostic prediction of patients with gastric cancer.

"D2 plus" lymphadenectomy is associated with improved survival in distal gastric cancer with clinical serosa invasion: a propensity score analysis.

The aim of this study was to elucidate the potential impact of "D2 plus" lymphadenectomy on the long-term survival of distal gastric cancer (GC) patients with clinical serosa invasion. A total of 394 distal GC patients with clinical serosa invasion who underwent at least standard D2 lymphadenectomy were enrolled. Patients were categorized into two groups according to the extent of lymphadenectomy: D2 group and "D2 plus" group. Propensity score matching was used to adjust for the differences in baseline characteristics. In the multivariate analysis for the whole study series, extent of lymphadenectomy was an independent prognostic factor for GC patients (P = 0.011). With the strata analysis, the significant prognostic differences between the two groups were only observed in patients at the IIIa-b or N1-3a stages. After matching, patients in "D2 plus" group still demonstrated a significantly higher 5-year overall survival rate than those in D2 group (55.3% versus 43.9%, P = 0.042). The common therapeutic value index of No. 12b, No. 12p, No. 14v and No. 13 LNs was 4.6, which was close to that of No. 5 LN station. In conclusion, "D2 plus" lymphadenectomy may be associated with improved overall survival in distal GC with clinical serosa invasion.

Effect of fragile histidine triad gene transduction on proliferation and apoptosis of human hepatocellular carcinoma cells.

AIM: To evaluate the inhibitory effects of human fragile histidine triad (FHIT) gene on cell proliferation and apoptosis in human hepatocellular carcinoma line Hep3B in vitro. METHODS: A recombinant pcDNA3.1 (+)/FHIT including the functional region of FHIT gene was constructed and transferred into human hepatocellular carcinoma cells in vitro. mRNA and protein expression of the FHIT gene in the transfected cells was detected by RT-PCR and Western blot, respectively. The effect of FHIT on proliferation was detected by MTT assay. Changes in cell cycle and apoptosis were assayed by flow cytometry. Five mice received subcutaneous transplantation of Hep3B-FHIT; 5 mice received subcutaneous transplantation of normal Hep3B and Hep3B-C as controls. The body weight of nude mice and tumor growth were measured. RESULTS: RT-PCR and Western blot analysis showed that the expression level of FHIT-mRNA and FHIT protein was higher in Hep3B cells after infection with pcDNA3.1 (+)/FHIT. The growth of Hep3B cells treated with pcDNA3.1 (+)/FHIT was significantly inhibited. The pcDNA3.1 (+)/FHIT-transfected Hep3B cells showed a significantly higher cell rate at G(0)-G(1) phase and increased apoptosis in comparison with controls (P < 0.05). The growth of transplanted tumor was inhibited markedly by FHIT. Tumors arising from the Hep3B-FHIT cells occurred much later than those arising from the Hep3B and Hep3B-C cells. The growth of Hep3B-FHIT cells was slow and the tumor volume was low. CONCLUSION: Transduction of FHIT gene inhibits the growth of human hepatocellular carcinoma cells and induces cell apoptosis in vivo and in vitro.

Effects of ultrasound on the evolution of plasma electrolytic oxidation process on 6061Al alloy.

The plasma electrolytic oxidation (PEO) process of 6061Al alloy was carried out under the conditions with and without the assistance of ultrasound, respectively. The effects of ultrasound on the evolution of voltage, micro-discharge, morphology and composition of PEO coatings were investigated. The results show that ultrasound can greatly decrease the dielectric breakdown voltage of the coatings, increase the number of micro-discharges while decrease their average size, promote the evolution of micro-discharges, decrease the number and the average size of residual discharge pores in the coatings after 30min of the process, promote the homogeneous distribution of elements and the formation of α-Al2O3 and 3Al2O3⋅2SiO2 in the coatings.