Appropriate follow-up period for odontogenic keratocyst: a retrospective study / 대한악안면성형재건외과학회지

Purpose@#The aim of this study was to conduct epidemiologic investigations on the pattern of the lesion and differences between treatment modalities in terms of recurrence by reviewing follow-up records to form a basis for planning patient follow-up visits. @*Materials and methods@#In this retrospective, single-center cohort study, 266 patients diagnosed with odontogenic keratocyst between 1993 and 2013 were included. Medical records and radiographic images were analyzed for age distribution, occurrence site and size, treatment modalities, and recurrence. @*Results@#The average age at first diagnosis was 33.1 years, and the male to female ratio was 1.33:1.00. The highest rate of incidence was in the third decade followed by the fourth, second, and fifth decades. The incidence in the maxilla was 34%, and 66% in the mandible. Mandibular ramus was most commonly involved. Lesions between 3 and 6 crowns were the most common, and the rate of recurrence increased with size. Enucleation after decompression had higher rate of recurrence (35.8%) than enucleation (27.1%), but there was no statistical significance. @*Conclusion@#The recurrence of odontogenic kerotocyst (OKC) was significantly associated with large size, multilocular form, and surgical procedure. A 10-year follow-up period is recommended to determine any recurrence of OKC.

Primary malignant mucosal melanoma of the maxillofacial area

Objectives@#We aimed to collect and report data from all patients who have been diagnosed with mucosal malignant melanoma to obtain the epidemiology and principles of current treatments. @*Materials and Methods@#Between January 2008 and December 2018, 20 patients underwent surgery or follow-up observations at Yonsei University Dental Hospital. The patients’ clinical information was reviewed retrospectively. @*Results@#Seventeen of 20 patients had undergone definitive surgery, while only 6 patients received adjuvant radiotherapy or systemic therapy. Eight of 20 patients, including those that had recurrent lesions, were provided immunotherapy. The 3-year survival for all stages was 50%, with a local recurrence rate of 75% and a metastasis rate of 65%. @*Conclusion@#The overall survival of patients receiving surgical treatment was longer than that of patients who did not undergo surgical resection.Eight of 20 patients received immunotherapy as the first-line regimen at our clinic, and those patients exhibited longer overall survival compared to patients in reported keynote studies.

Primary malignant mucosal melanoma of the maxillofacial area

Objectives@#We aimed to collect and report data from all patients who have been diagnosed with mucosal malignant melanoma to obtain the epidemiology and principles of current treatments. @*Materials and Methods@#Between January 2008 and December 2018, 20 patients underwent surgery or follow-up observations at Yonsei University Dental Hospital. The patients’ clinical information was reviewed retrospectively. @*Results@#Seventeen of 20 patients had undergone definitive surgery, while only 6 patients received adjuvant radiotherapy or systemic therapy. Eight of 20 patients, including those that had recurrent lesions, were provided immunotherapy. The 3-year survival for all stages was 50%, with a local recurrence rate of 75% and a metastasis rate of 65%. @*Conclusion@#The overall survival of patients receiving surgical treatment was longer than that of patients who did not undergo surgical resection.Eight of 20 patients received immunotherapy as the first-line regimen at our clinic, and those patients exhibited longer overall survival compared to patients in reported keynote studies.

Fabrication of palatal lift prosthesis for a patient with palatal defect / 대한치과보철학회지

This report is a case of 38-year old female patient who had a chief complaint about having pronounciation disorder after going under mass excision due to mucoepidermoid carcinoma. She was referred to department of prosthodontics, Yonsei university. Palatal lift prosthesis was fabricated which was then relined with tissue conditioner. Evaluations on phonetics and swallowing were done and improvements were shown. Tissue conditioner was replaced with heat polymerizing resin and the patient was satisfied with the results of treatment.

Osteosarcoma of the jaws in Koreans: analysis of 26 cases

OBJECTIVES: In order to assess clinical behavior, response to treatment, and factors influencing prognosis of Korean patients with osteosarcoma of the jaws (OSJ). MATERIALS AND METHODS: A retrospective study of clinical, and pathological records of 26 patients with OSJ treated at the Department of Oral and Maxillofacial Surgery in Yonsei University Dental Hospital from 1990 to March 2017. RESULTS: Of 26 patients, there were 9 men (34.6%) and 17 women (65.4%). Twenty-one of 26 patients had osteosarcoma of the mandible, and 5 of 26 patients had osteosarcoma of the maxilla. The histopathology of OSJ is highly variable, ranging from chondroblastic type (6 out of 26), osteoblastic type (10 out of 26), fibroblastic type (2 out of 26), to the rare variants like mixed type, small cell osteosarcoma types and more. All patients underwent gross total excision and only a few patients underwent neoadjuvant chemotherapy. Postoperative chemotherapy was given to most of the patients as adjuvant treatment or in combination with radiotherapy. The overall survival rate was 73.1% with an overall 2-year survival rate of 83.3%. The overall 5-,10-,15-year survival rates in this study were 73.5%, 73.5%, 49%, respectively. Using Kaplan-Meier analysis with log rank tests, the size of tumor (T-stage), and resection margins were found to affect the survival rate significantly. The chemotherapy was not significantly associated with improved survival rate. CONCLUSION: Surgical resection with a clear margin is the most important factor in disease survival. The role of chemotherapy and radiotherapy in OSJ remains controversial, and deserves further studies.

Osteosarcoma of the jaws in Koreans: analysis of 26 cases

OBJECTIVES: In order to assess clinical behavior, response to treatment, and factors influencing prognosis of Korean patients with osteosarcoma of the jaws (OSJ). MATERIALS AND METHODS: A retrospective study of clinical, and pathological records of 26 patients with OSJ treated at the Department of Oral and Maxillofacial Surgery in Yonsei University Dental Hospital from 1990 to March 2017. RESULTS: Of 26 patients, there were 9 men (34.6%) and 17 women (65.4%). Twenty-one of 26 patients had osteosarcoma of the mandible, and 5 of 26 patients had osteosarcoma of the maxilla. The histopathology of OSJ is highly variable, ranging from chondroblastic type (6 out of 26), osteoblastic type (10 out of 26), fibroblastic type (2 out of 26), to the rare variants like mixed type, small cell osteosarcoma types and more. All patients underwent gross total excision and only a few patients underwent neoadjuvant chemotherapy. Postoperative chemotherapy was given to most of the patients as adjuvant treatment or in combination with radiotherapy. The overall survival rate was 73.1% with an overall 2-year survival rate of 83.3%. The overall 5-,10-,15-year survival rates in this study were 73.5%, 73.5%, 49%, respectively. Using Kaplan-Meier analysis with log rank tests, the size of tumor (T-stage), and resection margins were found to affect the survival rate significantly. The chemotherapy was not significantly associated with improved survival rate. CONCLUSION: Surgical resection with a clear margin is the most important factor in disease survival. The role of chemotherapy and radiotherapy in OSJ remains controversial, and deserves further studies.

Use of a Combined Gene Expression Profile in Implementing a Drug Sensitivity Predictive Model for Breast Cancer / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Chemotherapy targets all rapidly growing cells, not only cancer cells, and thus is often associated with unpleasant side effects. Therefore, examination of the chemosensitivity based on genotypes is needed in order to reduce the side effects. MATERIALS AND METHODS: Various computational approaches have been proposed for predicting chemosensitivity based on gene expression profiles. A linear regression model can be used to predict the response of cancer cells to chemotherapeutic drugs, based on genomic features of the cells, and appropriate sample size for this method depends on the number of predictors. We used principal component analysis and identified a combined gene expression profile to reduce the number of predictors. RESULTS: The coefficients of determinanation (R²) of prediction models with combined gene expression and several independent gene expressions were similar. Corresponding F values, which represent model significances were improved by use of a combined gene expression profile, indicating that the use of a combined gene expression profile is helpful in predicting drug sensitivity. Even better, a prediction model can be used even with small samples because of the reduced number of predictors. CONCLUSION: Combined gene expression analysis is expected to contribute to more personalized management of breast cancer cases by enabling more effective targeting of existing therapies. This procedure for identifying a cell-type-specific gene expression profile can be extended to other chemotherapeutic treatments and many other heterogeneous cancer types.

Is elective neck dissection needed in squamous cell carcinoma of maxilla?

OBJECTIVES: To define the risk of occult cervical metastasis of maxillary squamous cell carcinoma (SCC) and the therapeutic value of elective neck dissection (END) in survival of clinically negative neck node (cN0) patients. MATERIALS AND METHODS: Sixty-seven patients with maxillary SCC and cN0 neck were analyzed retrospectively, including 35 patients with maxillary gingiva and 32 patients with maxillary sinus. RESULTS: Of 67 patients, 10 patients (14.9%) had occult cervical metastasis. The incidence of occult cervical metastasis of maxillary gingival SCC was higher than that of maxillary sinus SCC (17.1% and 12.5%, respectively). The 5-year overall survival rate was 51.9% for the END group and 74.0% for the non-END group. The success rate of treatment for regional recurrence was high at 71.4%, whereas that for local or locoregional recurrence was low (33.3% and 0%, respectively). CONCLUSION: The incidence of occult cervical metastasis of maxillary SCC was not high enough to recommend END. For survival of cN0 patients, local control of the primary tumor is more important than modality of neck management. Observation of cN0 neck is recommended when early detection of regional recurrence is possible irrespective of the site or T stage. The key enabler of early detection is patient education with periodic follow-up.

Revisiting radial forearm free flap for successful venous drainage / 대한악안면성형재건외과학회지

Tissue defect reconstruction using radial forearm free flap (RFFF) is a common surgical technique whose success or failure is mainly dependent on venous drainage. RFFF has two major venous outflow systems, superficial and deep vein. Drainage methods include combining both systems or using one alone. This review aims to recapitulate the vascular anatomy and network of RFFF as well as shed light on deep vein as a reliable venous drainage system. We also discuss basic evidence for and advantages of single microanastomosis with coalesced vein to overcome technical difficulties associated with the deep vein system.

Elective neck dissection versus observation in early stage oral squamous cell carcinoma: recurrence and survival

OBJECTIVES: To evaluate the results of elective neck dissection versus those of observation in the treatment of early stage oral squamous cell carcinoma and to identify factors related to recurrence and survival. MATERIALS AND METHODS: This was a retrospective study of 52 patients who underwent elective neck dissection and 27 who did not receive neck dissection. RESULTS: In survival analyses, elective neck dissection showed a benefit in overall recurrence (P=0.027), especially in stage I patients (P=0.024). With regard to survival, the benefit was statistically insignificant (P=0.990). In multivariable analysis, overall recurrence was independently related to poor histologic grade (odds ratio [OR]=9.65, P=0.006), and cancer-specific death was independently related to advanced age (OR=6.3, P=0.022), higher clinical T stage (OR=15.2, P=0.01), and poorly differentiated histologic grade (OR=6.6, P=0.025). CONCLUSION: Though there was lower recurrence in the elective neck dissection group, there were no statistically significant results on survival. The characteristics of the tumor itself, such as clinical T stage and poor histologic grade, may be more important in cancer-specific survival.

Novel Methods for Clinical Risk Stratification in Patients with Colorectal Liver Metastases / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: Colorectal cancer patients with liver-confined metastases are classified as stage IV, but their prognoses can differ from metastases at other sites. In this study, we suggest a novel method for risk stratification using clinically effective factors. MATERIALS AND METHODS: Data on 566 consecutive patients with colorectal liver metastasis (CLM) between 1989 and 2010 were analyzed. This analysis was based on principal component analysis (PCA). RESULTS: The survival rate was affected by carcinoembryonic antigen (CEA) level (p < 0.001; risk ratio, 1.90), distribution of liver metastasis (p=0.014; risk ratio, 1.46), and disease-free interval (DFI; p < 0.001; risk ratio, 1.98). When patients were divided into three groups according to PCA score using significantly affected factors, they showed significantly different survival patterns (p < 0.001). CONCLUSION: The PCA scoring system based on CEA level, distribution of liver metastasis, and DFI may be useful for preoperatively determining prognoses in order to assist in clinical decisionmaking and designing future clinical trials for CLM treatment.

Development of animal model for Bisphosphonates-related osteonecrosis of the jaw (BRONJ) / 대한악안면성형재건외과학회지

BACKGROUND: The aim of this study is to develop a rat model of bisphosphonates-related osteonecrosis of the jaw (BRONJ) that would be verified with clinical, radiological and histological examination, and to confirm the influence of concurrent bisphosphonates and steroids use upon the occurrence and aggravation of BRONJ. METHODS: Twenty seven rats were divided into 3 groups; Saline group (I), Zoledronate group (II), Zoledronate and Dexamethasone group (III). Rats got weekly intraperitoneal injection for 4 times and extraction of left maxillary and mandibular 1st, 2nd molars were followed. Consecutive injections were performed, and blood sampling for measurements of C-terminal crosslinked telopeptide of type I collagen and tartrate-resistant acid phosphate 5b rats were performed at the time of 2, 4 and 8 weeks. And then, rats were sacrificed and evaluated clinically, radiologically and histologically. RESULTS: 12/18 (66.6 %) of experimental group were diagnosed as BRONJ. There was no significant difference in incidence between zoledronate alone group (ll) and concurrent use of zoledronate and dexamethasone group (lll). CONCLUSIONS: Concurrent use of bisphosphonates and steroids increase incidence of BRONJ compared to saline group (l). Zoledronate alone group (ll) and concurrent use of zoledronate and dexamethasone group (lll) shows same incidence of BRONJ. Based on this study, the rat treated with bisphosphonates and steroids can be considered a novel, reliable and reproducible model to understand pathology of BRONJ.

Esthetic neck dissection using an endoscope via retroauricular incision: a report of two cases

Various surgical techniques, such as endoscopic surgery and robotic surgery, are developed to optimize the esthetic outcome even in operations for malignancy. A modified face-lift or retroauricular approach are used to minimize postoperative scarring. Recently, robot-assisted surgery is being done in various fields and considered as favorable treatment method by many surgeons. However its high cost is a nonnegligible fraction for many patients. On the other hand, endoscopic surgery, which is cheaper than robotic surgery, is minimally invasive with contentable neck dissection. Although it is a difficult technique for a beginner surgeon due to its limited operation view, we suppose it as an alternative method for robotic surgery. Herein, we report two cases of endoscopic neck dissection via retroauricular incision with a discussion regarding the pros and cons of endoscopic neck dissection.

Considerations and Protocols in Virtual Surgical Planning of Reconstructive Surgery for More Accurate and Esthetic Neomandible with Deep Circumflex Iliac Artery Free Flap / 대한악안면성형재건외과학회지

PURPOSE: The reconstruction of mandibular defects poses many difficulties due to the unique, complex shape of the mandible and the temporomandibular joints. With development of microvascular anastomosis, free tissue transplantation techniques, such as deep circumflex iliac artery (DCIA) flap and fibular free flap (FFF), were developed. The DCIA offers good quality and quantity of bone tissue for mandibular segmental defect and implant for dental rehabilitation. Virtual surgical planning (VSP) and stereolithography-guided osteotomy are currently successfully applied in three-dimensional mandibular reconstruction, but most use FFF. There are only a few articles on reconstruction with the DCIA that assess the postoperative results. METHODS: Three patients admitted during a five month period (April of 2013 to August of 2013) underwent resection of mandible and DCIA musculo-osseous reconstruction using a VSP and stereolithographic modeling and assessment of outcomes included technical accuracy, esthetic contour, and functional outcomes. RESULTS: This technique yielded iliac bone segment with excellent apposition and duplication of the preoperative plan. Flap survival was 100 percent and all patients maintained preoperative occlusion and contour. CONCLUSION: Based on our experience, we offer considerations and logically consistent protocols by classification of mandibular defects, and demonstrate the benefits in VSP and stereolithographic modeling of mandibular reconstructive surgery with DCIA flap.

Mandibular condyle and infratemporal fossa reconstruction using vascularized costochondral and calvarial bone grafts

There are some difficulties in approaching and removing the lesion in infratemporal fossa because of its anatomical location. After wide excision of tumor lesion, it is also difficult for reconstruction of mandibular condyle and cranium base on infratemporal fossa. Besides, there are some possibilities of cerebrospinal fluid leakage, intracranial infection and bone resorption. It is also challenging for functional reconstruction that allows normal mandibular movement, preventing mandibular condyle from invaginating into the skull. In this report, we present 14-month follow-up results of a patient who had undergone posterior segmental mandibulectomy including condyle and infratemporal calvarial bone and mandible reconstruction with free vascularized costochondral rib and calvarial bone graft to restoration of the temporomandibular joint area.

Incidence and Risk Factors of Infectious Complications Related to Implantable Venous-Access Ports

OBJECTIVE: The purpose of this study was to determine the incidence and risk factors of infections associated with implantable venous access ports (IVAPs). MATERIALS AND METHODS: From August 2003 through November 2011, 1747 IVAPs were placed in our interventional radiology suite. One hundred forty four IVAPs were inserted in patients with hematologic malignancy and 1603 IVAPs in patients with solid tumors. Among them, 40 ports (23 women and 17 men; mean age, 57.1 years; range, 13-83) were removed to treat port-related infections. We evaluated the incidence of port-related infection, patient characteristics, bacteriologic data, and patient progress. Univariable analyses (t test, chi-square test, and Fisher's exact test) and multiple logistic regression analyses were used to determine the risk factors for IVAP related infection. RESULTS: Overall, 40 (2.3%) of 1747 ports were removed for symptoms of infection with an incidence rate of 0.067 events/1000 catheter-days. According to the univariable study, the incidences of infection were seemingly higher in the patients who received the procedure during inpatient treatment (p = 0.016), the patients with hematologic malignancy (p = 0.041), and the patients receiving palliative chemotherapy (p = 0.022). From the multiple binary logistic regression, the adjusted odds ratios of infection in patients with hematologic malignancies and those receiving palliative chemotherapy were 7.769 (p = 0.001) and 4.863 (p = 0.003), respectively. Microorganisms were isolated from 26 (65%) blood samples, and two of the most causative organisms were found to be Staphylococcus (n = 10) and Candida species (n = 7). CONCLUSION: The underlying hematologic malignancy and the state of receiving palliative chemotherapy were the independent risk factors of IVAP-related infection.

An atypical case of rare salivary malignancy, hyalinizing clear cell carcinoma

As an uncommon, malignant salivary gland tumor with female predominance, hyalinizing clear cell carcinoma (HCCC) is regarded as an indolent tumor. The diagnosis of this rare tumor is challenging, and it depends on microscopic and immunohistochemical (IHC) studies. Although it is regarded as an indolent tumor, there are reports of unconventional forms with aggressive clinical courses. We report an atypical case of this rare tumor, HCCC, in a male patient who had a relatively large-sized mass (3.8x3.0 cm) on the right mouth floor with ipsilateral neck node metastasis. The clinical, radiological, pathological, and IHC features together with the clinical course are described.

Inducing re-epithelialization in skin wound through cultured oral mucosal keratinocytes

OBJECTIVES: The purpose of this study was to investigate the wound healing effect of primary cultured oral mucosal keratinocytes (OMKs) and to assess their roles in skin wounds. MATERIALS AND METHODS: OMK labeled with BromodeoxyUridine were scattered onto 1.5x1.5 cm skin defects of adult female nude mice (OMK group, n=15). For the control, culture media were placed on the wound (control group, n=15). Mice in both groups were sacrificed at three days (n=5), one week (n=5), and two weeks (n=5), and histomorphometric and immunoblot analyses with keratinocyte growth factor (KGF), interleukin (IL)-6, and IL-1alpha antibody were performed for the biopsied wound specimen. To verify the effect of the cytokine, rhIL-1alpha was applied instead of OMK transplantation, and the OMK and control groups were compared with regard to re-epithelialization. RESULTS: Histomorphometric analyses demonstrated faster re-epithelialization in the graft group than in the control group at the third day, first week, and second week. Newly forming epithelium showed maintenance of the histological character of the skin epithelium. The graft group showed superior expression of KGF, IL-6, and IL-1alpha protein, compared with the control group. Similar faster re-epithelialization was observed after treatment with rhIL-1alpha instead of OMK transplantation. CONCLUSION: We successfully confirmed that the graft of primary cultured OMKs promoted regeneration of skin defects. The mechanism of accelerated wound healing by primary cultured OMKs was attributed to inducement of cytokine expression as required for re-epithelialization.

Heparin-induced Thrombocytopenia Type II after Free Flap Operation

Tunnelized-facial Artery Myomucosal Island Flap (t-FAMMIF) for Palatomaxillary Reconstruction: A Report of Two Cases