Smaller tumor size is associated with poor survival in T4b colon cancer

AIM: To hypothesize that in patients with colon cancer showing heavy intestinal wall invasion without distant metastasis(T4b N0-2M0), small tumor size would correlate with more aggressive tumor behaviors and therefore poorer cancer-specific survival(CSS).METHODS: We analyzed T4 b N0-2M0 colon cancer patients in the Surveillance, Epidemiology and End Results(SEER) database. A preliminary analysis of T4 b N0-2M0 colon cancer patients at the Fudan University Shanghai Cancer Center is also presented.RESULTS: A total of 1734 T4 b N0-2M0 colon cancer patients from the SEER database were included. Kaplan-Meier analysis revealed decreasing CSS with decreasing tumor size(P < 0.001). Subgroup analysis showed a significant association between poorer CSS with smaller tumor size in T4 b N0 patients(P = 0.024), and a trend of association in T4 b N1(P = 0.182) and T4 b N2 patients(P = 0.191). Multivariate analysis identified tumor size as an independent prognostic factor for CSS in T4 b N0-2M0 patients(P = 0.024). Preliminary analysis of Fudan University Shanghai Cancer Center samples suggested the 5-year CSS was 50.0%, 72.9% and 77.1% in patients with tumors ≤ 4.0 cm, 4.0-7.0 cm and ≥ 7.0 cm.CONCLUSION: Smaller tumor size is associated with poorer CSS in the T4 b N0-2M0 subset of colon cancer, particularly in the T4 b N0M0 subgroup.

Fabrication and Characterization of Chitosan-Silk Fibroin/Hydroxyapatite Composites via in situ Precipitation for Bone Tissue Engineering

Homogeneous chitosan-silk fibroin/hydroxyapatite （CS-SF/HA） composites were prepared by in situ precipitation method driven by a multiple-order template. The morphology of the composites was investigated by scanning electron microscope （SEM） and transmission electron microscope （TEM）. The compositional analysis was carried out by X-ray diffraction analysis （XRD） and Fourier transformed infrared spectroscopy （FTIR）. The mechanical properties and biocompatibility of the composites were also determined. The results indicated that the inorganic particles of uniform size （50 nm） were well-dispersed among the CS-SF matrices. The compressive modulus of the CS-SF/HA composites was enhanced with the increasing amount of SF. The in vitro results suggested that the MC3T3-E1 osteoblast-like cells on CS-SF/HA composite disks displayed strong bonding and spreading, and the cell proliferation cultured on each composite disk increased throughout the culture period for up to 7 days. Especially, the samples with higher content of SF had much better biological properties. The evidences proved that the CS-SF/HA composites possessed excellent biocompatibility. By using the freeze-drying technique, hierarchical porous scaffolds with pores ranging from 50 μm to 200 μm were obtained. This work presented the advantages of in situ precipitation method to prepare the organic/inorganic composites, and a multiple-order template was introduced in the system to improve the properties of the composites by combining the merits of each organic template.