Li-Tzu Lee

Comparison of the Effectiveness of Autologous Fibrin Glue and Macroporous Biphasic Calcium Phosphate as Carriers in the Osteogenesis Process With or Without Mesenchymal Stem Cells

Background: Facial bone reconstruction has been a challenge for oral and maxillofacial surgeons for a long time. Recently, some studies have reported the use of stem cells in facial reconstruction to achieve osteogenesis. However, to ensure that stem cells remain in the recipient site, a biocompatible carrier is needed to transfer the stem cells. Fibrin glue has been shown to promote hemostasis in wound management and accelerate soft tissue healing, but the role of fibrin glue in bone regeneration remains debatable. The purpose of this study was to compare the effectiveness of autologous fibrin glue and macroporous biphasic calcium phosphate (MBCP) as carriers in the osteogenesis process with/without mesenchymal stem cells. Methods: Fifteen New Zealand white rabbits were used in this study. Mesenchymal stem cells were harvested from the iliac bone, and autologous fibrin glue was made from peripheral blood. Three cranial defects with a diameter of 6 mm were created over the cranial bone in each rabbit. The 15 animals were separated into 2 groups. The first group contained 12 rabbits. The grafted substances placed over the regions of defect were: (1) stem cells plus autologous fibrin glue; (2) stem cells plus MBCP; (3) defect alone as control. In the second group of 3 rabbits, the cranial defects were grafted with: (1) autologous fibrin glue alone; (2) MBCP alone; (3) defect alone as control. Rabbits were sacrificed at 1, 2 and 3 months post operation. Radiography and histology were used to detect bone formation. Results: Stem cells plus autologous fibrin glue induced more bone formation 2 months post operation and more mature bone was found 3 months post operation compared with the other groups. MBCP with or without stem cells showed moderate tissue reaction, including giant cell, histiocyte and eosinophil cell accumulation. Conclusion: Using stem cells plus autologous fibrin glue as the carrier may accelerate new bone regeneration.

Effect of a nonthermal-atmospheric pressure plasma jet on wound healing: An animal study.

Background The use of a nonthermal plasma (NTP) jet in the treatment of living tissue has been the subject of considerable interest in the field of medical technology, and has the potential to reduce the recovery time of open wounds. We aimed to investigate the wound‐healing process by clinical observation, blood tests, and expression of cell adhesion markers and reactive oxygen species in NTP jet‐treated rats. Methods This study utilized Sprague‐Dawley (SD) rats as experimental subjects, and wounds measuring 2 cm × 2 cm were produced on the animals’ backs. The experimental group was treated with NTP for 5 min/d for 4 weeks. The NTP was injected in a diffused manner into the cage housing the rats. The SD rats that had not received plasma treatment were designated as the control group. Blood was drawn on Postoperative Day 2, Day 4, and at 3 months. An immunohistochemical stain of E‐cadherin and 4‐hydroxy‐2‐nonenal (4‐HNE), a reactive oxygen species marker, were evaluated and quantified for analysis using a CMYK color model. Results A total of 35 SD rats were included in the study (25 in the NTP group and 10 in the control group). Low dose plasma treatment shortened the wound‐healing time without damaging organs. In the NTP group, the white blood cell counts at Day 2 post‐NTP treatment was not increased significantly more than that in the control group. After quantification of immunohistochemical staining, 4‐HNE was increased at Day 14 compared with Day 7 (16.16 ± 12.81% vs. 55.11 ± 8.11%, p < 0.001), and E‐cadherin was also increased (52.17 ± 14.96% vs. 70.46 ± 12.78%, p = 0.04) in the NTP group. After comparison of NTP and the control, it was observed that 4‐HNE and E‐cadherin were increased in the NTP group on Day 14. Conclusion Short‐term, low‐dose NTP wound treatment was demonstrated to accelerate wound healing in SD rats without vital organ toxicity.

Quantitative physiology and immunohistochemistry of oral lesions

Angiogenesis and hypoxia are reported to correlate with tumor aggressiveness. In this study, we investigated the potential of optically measured total hemoglobin concentration (THC) and blood oxygen saturation (StO2) as a quantitative measure of angiogenesis and hypoxia in oral lesions with an immunohistochemical comparison. 12 normal subjects and 40 oral patients (22 oral squamous cell carcinoma (SCC), 18 benign/premalignant lesions including 11 verrucous hyperplasia (VH) and 7 hyperkeratosis/parakeratosis (HK)) were studied. The results showed that the THC measurement was consistent with vascular endothelial growth factor (VEGF) and microvessel staining in the stromal area, but StO2 was not associated with HIF-1α. We observed inflammation induced neovascular formation in the stromal area of VH and HK that were likely attributed to higher-than-control THC and StO2 and resulted in no difference in optical measurements between all lesions. However, we found that in majority of SCC, the ratio of THC and StO2 levels between lesions and the surrounding tissues provide potential distinguishing characteristics from VH, which are not visually differentiable from SCC, with a sensitivity, specificity, and accuracy of 91%, 68%, and 76%, respectively.

Clinical implications of recent exodontia before diagnosis of gingival squamous cell carcinoma: A new classification.

The purpose of this study was to clarify the clinical implications of cases with recent dental extractions to establish a new classification of gingival squamous cell carcinoma (SCC).

Evaluation of saliva and plasma cytokine biomarkers in patients with oral squamous cell carcinoma

The aim of this study was to investigate potential biomarkers in human saliva and plasma to aid in the early diagnosis of oral squamous cell carcinoma (OSCC). Saliva and plasma samples obtained from OSCC patients (n=41) and non-oral cancer patients (n=24) were analyzed by Luminex Bead-based Multiplex Assay. Data were analyzed using the non-parametric Mann-Whitney U-test, Kruskal-Wallis test, and receiver operating characteristics curve (ROC) to evaluate the predictive power of 14 biomarkers individually for OSCC diagnosis. The plasma level of IP-10 in early OSCC differed significantly from that in controls. Among the salivary biomarkers, IL-1β, IL-6, IL-8, MIP-1β, eotaxin and IFN-γ and TNF-α showed significant differences between OSCC patients and controls. With respect to carcinogenesis, significant differences in plasma levels of eotaxin, G-CSF, and IL-6 were found between OSCC stages III/IV and OSCC stages I/II. The area under the curve (AUC) for OSCC vs. control was greater than 0.7 for plasma IP-10 and saliva IL-1β, IL-6, IL-8, and TNF-α. The study findings indicate that salivary biomarkers may serve a useful role as a complementary adjunct for the early detection of oral OSCC. With regard to the evaluation of tumour progression, plasma eotaxin, G-CSF, and IL-6 may help in the detection of advanced OSCC. However, the correlation between saliva and plasma biomarkers in OSCC was weak.

The correlation between HIF-1 alpha and VEGF in oral squamous cell carcinomas: Expression patterns and quantitative immunohistochemical analysis

Background: The prognostic predict biomarkers are important in oral squamous cell carcinoma (OSCC). We investigated the expression patterns and quantitation of hypoxia‐inducible factor‐1 alpha (HIF‐1&agr;) and vascular endothelial growth factor (VEGF) in OSCC patients. Among OSCC patients with recurrence and metastasis, the expression percentages of HIF‐1&agr; and VEGF also were analyzed. Methods: Thirty‐eight patients (8 hyperkeratosis, 30 oral squamous cell carcinoma) were included in this study. In the follow‐up period, 5 OSCC patients had metastasis and 12 OSCC patients had local recurrence. We used computer‐assisted image processing to analyze immunohistochemistry (IHC). The quantitative analysis of IHC slides, including upper‐layer epithelium (U) and lower‐layer epithelium (L), was calculated. Results: We found homogeneous expression of VEGF in the epithelium. However, two patterns of HIF‐1&agr; expression were observed: homogeneous and heterogeneous. The highest U + L layer percentage in HIF‐1&agr; and VEF expression had significant association in tumor metastasis and recurrence (p < 0.001 in HIF‐1&agr; and p < 0.001 in VEGF). U + L layer HIF‐1&agr; expression percentage was >156.4%, and the survival rate was poor (p < 0.001). Conclusion: HIF‐1&agr; expression was not only influenced by tumor hypoxia, it also reflected tumor cell characteristics. High concentrations of VEGF and HIF‐1&agr; may have value as prognostic markers of tumor metastasis and recurrence.

Neurilemoma of the Tongue: the Diagnostic Dilemma in a Case

Neurilemoma, also termed Schwannoma, is a benign tumor of Schwann cell origin. This neoplasm can occur at any location in the oral cavity and is usually asymptomatic. MRI is an excellent tool for diagnosis. Treatment is by surgical excision and malignant change is rare. We report a case of a young female who was admitted with a swelling in the anterior portion of the tongue. The mass was light purple in color and became larger when the patient flexed her neck. MRI showed a uniformly round or oval mass with a moderately bright signal on Ti-weighted image and a bright heterogeneous signal on T2-weighted image. Under the impression of hemangioma, angiography was performed. The tumor was excised and histopathologic examination showed a typical neurilemoma with dilated blood vessels and organizing thrombi. The patient recorvered well after surgery with complete and rapid relief of symptoms. No recurrence was noted at one-year follow-up.

Novel application of artificial dermis plus autologous vital epithelial cells: improved wound epithelialization.

The purpose of this study was to evaluate artificial dermis with the simultaneous addition of autologous epithelial cells for oral lesion defect reconstruction. Surgical wounds reconstructed with artificial dermis plus scraped epithelial cells were evaluated in 5 patients with oral benign lesions or squamous cell carcinoma. Clinical follow-up indices included scar formation and tissue surface texture observation. The neomucosal layers were analyzed histologically to establish the degree of epithelialization. Clinical observation showed that the oral mucosal texture was smoother in artificial dermis with added epithelial cells at 4 weeks postoperation compared with artificial dermis alone. The wound contraction and scar formation processes were slow. Viable epithelial cells with flat rete ridges remained in the artificial dermis, and a neoepithelial layer was present in the histological findings. We showed that healthy granulation tissue and neoepithelial formation in artificial dermis with epithelial cells was beneficial for the repair of oral defects. Scraping oral epithelial cells and applying them to artificial dermis assisted in the early preparation of composite grafts and minimized requirement for donor sites. This technique may improve the treatment of patients with oral benign tumors and early-stage squamous cell carcinoma.

Abstract 4328: Broadband diffuse reflectance spectroscopy noninvasively detected in vivo hemoglobin concentration and oxygen saturation of normal and malignant oral tissues

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC Tumor physiological properties play an important role in cancer diagnosis and treatments. Diffuse reflectance spectroscopy has emerged as an important technique that provides several unique measurable parameters for characterization of a wide variety of tissue samples. By illuminating visible-NIR light at one location of tissue surface (source position) and collecting diffused light at another location (detection position) using optical fibers, we are able to access tissue physiological properties including total hemoglobin concentration (THC) and oxygen saturation (StO2). The depth of the measured tissue is determined by the source-detection separation that is approximately one third to one half of the separation. In oral cancers, close associations were found between tumor progression and tumor angiogenesis and hypoxia through the molecular markers. However, the prognostic and therapeutic value of these markers is not clearly known. The first goal of this study is to demonstrate the visibility of monitoring tissue THC and StO2 of normal and squamous cell carcinoma (SCC), which represent ∼95% of oral malignancies. Our 2nd goal is to compare these optical measured physiological properties to molecular markers from the same tissues. We have collected data from 25 SCC and 24 non-SCC (hyperplasia and dysplasia) patients at the department of dentistry, Taichung Veterans General Hospital. Adjacent normal sites were measured optically as well in the same patient. Optical measurements were analyzed by employing a physical model of light transport inside the tissue to extract THC and StO2. From all measurements, the THC and StO2 have a range of 25 and 229 uM and of 25 and 100%, respectively, while the source-detection separation at 4 mm (the detection depth 1.3 to 2 mm) was used. SCC did not show significant different THC and StO2 (mean±STD: 117±48 uM and 72±19%, respectively) from the normal site of the same patient (115±61 uM and 69±19%, respectively) and the non-SCC tissues (117±49 uM and 68±22%). While shorter source-detection separation was used (the detection depth was less than 1mm), the results from 7 SCC and 7 non-SCC patients show higher THC than normal and non-SCC tissues (233 uM versus 182 uM). Well oxygenated tissue layers were detected in both SCC, non-SCC, and normal sites with a range of 92 and 100%. The data indicated that both normal and malignant oral tissues are well oxygenated. Increased THC in SCC sites was observed only when the surface layer at the depth less than 1 mm was compared. Further analysis from all tissue sites will be performed to confirm this finding. The results of molecular markers will be compared with these optical measurements and the prognostic and therapeutic value of these markers will be discussed. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4328.

The Prognostic Significance of Adequate Surgical Margin for Head and Neck Sarcomas: A Retrospective Study of Thirty-one Cases

The aim of this study is to report our experience in the treatment of head and neck sarcomas. The medical charts and histopathologic features of thirty- one head and neck sarcomas at Taichung Veterans General Hospital between 1982 and 2007 were reviewed. Seventeen (54.8%) of the patients were male, while 14 (45.2%) were female. The common sites were the mandible (n=13), maxilla (n=7) and neck (n=7). Malignant fibrous histiocytoma (n=11) and osteosarcoma (n=8) are the most common lesions. Surgical resections were performed in 28 cases. Among them, local recurrence was found in 9 patients, and distant metastasis was proved in 4 patients. The overall 5-year survival rate was 50%. Surgical margin involvement and local recurrence were the main causes of death (P=0.006 and P=0.010, respectively). Of 13 patients with margin involvement, six developed local recurrence within a mean period of 20 months; and the mean survival period of expired patients with margin involvement was 33 months. In our series, young-to-middle-aged (＜50 years) females had poor 5-year survival rates (30%). Inadequate soft tissue margin resection may be due to gender, age and cosmetic concerns.