Poor prognostic factors in human papillomavirus-positive head and neck cancer: who might not be candidates for de-escalation treatment?

BACKGROUND/AIMS@#Since patients with human papillomavirus (HPV)-associated head and neck squamous cell carcinoma (HNSCC) have favorable outcomes after treatment, treatment de-escalation for these patients is being actively investigated. However, not all HPV-positive HNSCCs are curable, and some patients have a poor prognosis. The purpose of this study was to identify poor prognostic factors in patients with HPV-positive HNSCC.@*METHODS@#Patients who received a diagnosis of HNSCC and tested positive for HPV from 2000 to 2015 at a single hospital site (n = 152) were included in this retrospective analysis. HPV typing was conducted using the HPV DNA chip assay or liquid bead microarray system. Expression of p16 in the tumors was assessed by immunohistochemistry. To determine candidate factors associated with overall survival (OS), univariate and multivariable Cox regression analyses were performed.@*RESULTS@#A total of 152 patients with HPV-positive HNSCC were included in this study; 82.2% were male, 43.4% were current or former smokers, and 84.2% had oropharyngeal cancer. By univariate analysis, old age, performance status ≥ 1, non-oropharyngeal location, advanced T classification (T3–4), and HPV genotype 18 were significantly associated with poor OS. By multivariable analysis, performance status ≥ 1 and non-oropharyngeal location were independently associated with shorter OS (hazard ratio [HR], 4.36, p = 0.015; HR, 11.83, p = 0.002, respectively). Furthermore, HPV genotype 18 positivity was also an independent poor prognostic factor of OS (HR, 10.87, p < 0.001).@*CONCLUSIONS@#Non-oropharyngeal cancer, poor performance status, and HPV genotype 18 were independent poor prognostic factors in patients with HPV-positive HNSCC. Patients with these risk factors might not be candidates for de-escalation treatment.

Sentinel Lymph Node Centered Selective Neck Dissection Does Not Have Benefits Over Supraomohyoid Neck Dissection in Patients with cT1T2N0 Tongue Cancer / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: This study aimed to evaluate the clinical efficacy of sentinel node centered selective neck dissection in patients with early stage tongue cancer (T1T2N0). SUBJECTS AND METHOD: Lymphoscintigraphy was performed for 12 patients, subsequently followed by sentinel node centered selective neck dissection. The location of the sentinel node, pathological confirmation of node metastasis, and follow-up recurrence were analyzed. RESULTS: In total, 19 sentinel lymph nodes were identified. Of these, 18 were located in levels I to III, and one in level IV. After surgery, 3 patients (25%) were diagnosed with neck node metastasis: two experienced sentinel node metastasis and one experienced skipped metastasis. During follow-up, 3 of the 12 patients (25%) experienced recurrence. CONCLUSION: The recurrence of lymph node could be covered with supraomohyoid neck dissection, which indicates that it has superiority over sentinel node centered selective neck dissection in preventing recurrence in T1T2N0 tongue cancer patients.

Corrigendum: Study Protocol of Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro)

No abstract available.

Study Protocol of Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro)

BACKGROUND: The ongoing Multicenter Prospective Cohort Study of Active Surveillance on Papillary Thyroid Microcarcinoma (MAeSTro) aims to observe the natural course of papillary thyroid microcarcinoma (PTMC), develop a protocol for active surveillance (AS), and compare the long-term prognosis, quality of life, and medical costs between the AS and immediate surgery groups. METHODS: This multicenter prospective cohort study of PTMC started in June 2016. The inclusion criteria were suspicious of malignancy or malignancy based on fine needle aspiration or core needle biopsy, age of ≥18 years, and a maximum diameter of ≤1 cm. If there was no major organ involvement, no lymph node/distant metastasis, and no variants with poor prognosis, the patients were explained of the pros and cons of immediate surgery and AS before selecting AS or immediate surgery. Follow-up visits (physical examination, ultrasonography, thyroid function, and questionnaires) are scheduled every 6 months during the first 2 years, and then every 1 year thereafter. Progression was defined as a maximum diameter increase of ≥3, ≥2 mm in two dimensions, suspected organ involvement, or lymph node/distant metastasis. RESULTS: Among 439 enrolled patients, 290 patients (66.1%) chose AS and 149 patients (33.9%) chose immediate surgery. The median follow-up was 6.7 months (range, 0.2 to 11.9). The immediate surgery group had a larger maximum tumor diameter, compared to the AS group (7.1±1.9 mm vs. 6.6±2.0 mm, respectively; P=0.014). CONCLUSION: The results will be useful for developing an appropriate PTMC treatment policy based on its natural course and risk factors for progression.

Clinical Features and Outcomes of Patients in Neonatal Intensive Care Requiring Laryngologic Consultation for Airway Disorders / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Airway problems frequently occur in neonatal patients requiring intensive care due to high prevalence of intubation history and congenital conditions that are linked to craniofacial or upper aerodigestive tract anomalies. However, many investigations on airway disorders have examined large populations of hospitalized children without focusing on those treated in the intensive care unit (ICU). Here we present the clinical features and outcomes in infants hospitalized with airway-related problems at the neonatal ICU. SUBJECTS AND METHOD: A total 69 patients were studied from May 2005 to December 2012, with each examined by an otolaryngologist while in neonatal ICU (NICU) for possible airway problems. Descriptive analysis was used in evaluating illnesses suffered and subsequent upper airway treatments. Factors associated with tracheostomy were identified by multivariate analysis. RESULTS: The median age of infants was 30 days (range, 1-237 days), with a male-to-female ratio of 1.38. The median gestational age was 35⁺³ weeks, and the mean birth weight was 2.35±0.89 kg. Overall, 40 patients had histories of intubation (median duration, 36 days; range, 1-204 days). The most common diagnosis in the upper airway exam was laryngomalacia (n=12), followed by subglottic stenosis (n=10) and micrognathia (n=8). Tracheostomy was performed in 38 patients (55.1%). In multivariate analysis, intubation history was identified as the only variable demonstrating a significant independent association with tracheostomy (p=0.006). CONCLUSION: Upper airway problems in NICU patients are due to a variety of disorders. Precise diagnosis and treatment is achievable through bedside and intraoperative assessments. Patients with a history of intubation are at increased risk of tracheostomy.

Comparison of the Clinical Outcomes of Patients with Squamous Cell Carcinoma of the Tonsil Receiving Postoperative Ipsilateral Versus Bilateral Neck Radiotherapy: A Propensity Score Matching Analysis (KROG 11-07) / Journal of the Korean Cancer Association, 대한암학회지

@#PURPOSE: The impact of postoperative ipsilateral neck radiotherapy (INRT) versus bilateral neck radiotherapy (BNRT) on the clinical outcomes of patients with tonsillar squamous cell carcinoma was analyzed retrospectively. MATERIALS AND METHODS: Between October 2001 and June 2012, 241 patients with T1-2 and N0-N2b tonsillar carcinoma from 16 institutes underwent postoperative INRT (n=84) or BNRT (n=157) following a tonsillectomy. Seventy patients were identified from each group by propensity score matching and compared in terms of the overall survival (OS), disease-free survival (DFS), locoregional relapse-free survival (LRRFS), and distant metastasis-free survival (DMFS) rates calculated using the Kaplan-Meier method with a log-rank test. RESULTS: The median follow-up was 55 months (range, 3 to 133 months). The survival outcomes in the INRT and BNRT groups were similar: 5-year OS (92.8% vs. 94.0%, p=0.985), DFS (80.5% vs. 94.2%. p=0.085), LRRFS (88.1% vs. 97.1%, p=0.083), and DMFS (92.7% vs. 97.0%, p=0.370). Subgroup analysis revealed no contralateral neck recurrence in 61 patients with T1-2N0-2a regardless of the treatment groups. For 79 patients with N2b, contralateral neck recurrence was more common in the INRT group than in the BNRT group (7.9% vs. 0.0%), but the difference was not significant (p=0.107). The overall grade ≥ 2 toxicities were lower in the INRT group: acute (45.7% vs. 74.3%, p=0.001) and late (4.3% vs. 31.4%, p < 0.001), respectively. CONCLUSION: INRT is an attractive strategy for patients with T1-2N0-2a tonsillar carcinoma compared to BNRT. For patients with N2b, there was a small risk of contralateral neck recurrence when treated with INRT, but its impact on the OS was limited with successful salvage treatment.

Guidelines for the Surgical Management of Laryngeal Cancer: Korean Society of Thyroid-Head and Neck Surgery

Korean Society of Thyroid-Head and Neck Surgery appointed a Task Force to develop clinical practice guidelines for the surgical treatment of laryngeal cancer. This Task Force conducted a systematic search of the EMBASE, MEDLINE, Cochrane Library, and KoreaMed databases to identify relevant articles, using search terms selected according to the key questions. Evidence-based recommendations were then created on the basis of these articles. An external expert review and Delphi questionnaire were applied to reach consensus regarding the recommendations. The resulting guidelines focus on the surgical treatment of laryngeal cancer with the assumption that surgery is the selected treatment modality after a multidisciplinary discussion in any context. These guidelines do not, therefore, address non-surgical treatment such as radiation therapy or chemotherapy. The committee developed 62 evidence-based recommendations in 32 categories intended to assist clinicians during management of patients with laryngeal cancer and patients with laryngeal cancer, and counselors and health policy-makers.

Exploratory Study on Guide Wire-Guided Tongue Resection under Ultrasonography for Adequate Safe Margins in Tongue Cancer Surgery / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The adequate safety margin in tongue cancer is the most important prognostic factor for local recurrence and survival. This study aimed to evaluate the resection margins using a new technique of tongue resection under the guidance of guide wire under ultrasonography in patients with tongue cancer. SUBJECTS AND METHOD: In this prospective study, 10 patients with presurgical, biopsy-proven, clinical T1 or T2 tongue squamous cell carcinomas underwent resection under the guidance of guide wire inserted using ultrasonography. The data of resection margins of 37 patients who underwent partial glossectomy using the conventional method of palpation were used as control data. RESULTS: The mean safety margins (mm) of the experimental group were 7.59±4.30 (anterior), 8.56±4.69 (posterior), 5.25±3.01 (superior), 5.93±3.66 (inferior), 13.00±13.29 (medial), 5.78±2.64 (deep), and 6.67±3.06 (lateral). There were no differences in the safety margins between the two groups. CONCLUSION: Using guide wire under ultrasonography was not superior to the conventional method for partial glossectomy for having adequate resection margins.

Activation of K+ channel by 1-EBIO rescues the head and neck squamous cell carcinoma cells from Ca2+ ionophore-induced cell death

Ion channels in carcinoma and their roles in cell proliferation are drawing attention. Intracellular Ca2+ ([Ca2+]i)-dependent signaling affects the fate of cancer cells. Here we investigate the role of Ca(2+)-activated K+ channel (SK4) in head and neck squamous cell carcinoma cells (HNSCCs) of different cell lines; SNU-1076, OSC-19 and HN5. Treatment with 1 microM ionomycin induced cell death in all the three cell lines. Whole-cell patch clamp study suggested common expressions of Ca(2+)-activated Cl- channels (Ano-1) and Ca(2+)-activated nonselective cation channels (CAN). 1-EBIO, an activator of SK4, induced outward K+ current (ISK4) in SNU-1076 and OSC-19. In HN5, ISK4 was not observed or negligible. The 1-EBIO-induced current was abolished by TRAM-34, a selective SK4 blocker. Interestingly, the ionomycin-induced cell death was effectively prevented by 1-EBIO in SNU-1076 and OSC-19, and the rescue effect was annihilated by combined TRAM-34. Consistent with the lower level of ISK4, the rescue by 1-EBIO was least effective in HN5. The results newly demonstrate the role of SK4 in the fate of HNSCCs under the Ca2+ overloaded condition. Pharmacological modulation of SK4 might provide an intriguing novel tool for the anti-cancer strategy in HNSCC.

The Role of Neoadjuvant Chemotherapy in the Treatment of Nasopharyngeal Carcinoma: A Multi-institutional Retrospective Study (KROG 11-06) Using Propensity Score Matching Analysis / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: We compared the treatment results and toxicity in nasopharyngeal carcinoma (NPC) patients treated with concurrent chemotherapy (CCRT) alone (the CRT arm) or neoadjuvant chemotherapy followed by CCRT (the NCT arm). MATERIALS AND METHODS: A multi-institutional retrospective study was conducted to review NPC patterns of care and treatment outcome. Data of 568 NPC patients treated by CCRT alone or by neoadjuvant chemotherapy followed by CCRT were collected from 15 institutions. Patients in both treatment arms were matched using the propensity score matching method, and the clinical outcomes were analyzed. RESULTS: After matching, 300 patients (150 patients in each group) were selected for analysis. Higher 5-year locoregional failure-free survival was observed in the CRT arm (85% vs. 72%, p=0.014). No significant differences in distant failure-free survival (DFFS), disease-free survival (DFS), and overall survival were observed between groups. In subgroup analysis, the NCT arm showed superior DFFS and DFS in stage IV patients younger than 60 years. No significant difference in compliance and toxicity was observed between groups, except the radiation therapy duration was slightly shorter in the CRT arm (50.0 days vs. 53.9 days, p=0.018). CONCLUSION: This study did not show the superiority of NCT followed by CCRT over CCRT alone. Because NCT could increase the risk of locoregional recurrences, it can only be considered in selected young patients with advanced stage IV disease. The role of NCT remains to be defined and should not be viewed as the standard of care.

Induction chemotherapy in head and neck squamous cell carcinoma of the paranasal sinus and nasal cavity: a role in organ preservation

BACKGROUND/AIMS: The role of induction chemotherapy (IC) for eyeball preservation has not been established in head and neck squamous cell carcinoma (HNSCC) of the paranasal sinus and nasal cavity (PNSNC). Periorbital involvement frequently leads to eyeball exenteration with a margin of safety. We evaluated the treatment outcomes, including survival and eyeball preservation, of patients who received IC for HNSCC of the PNSNC. METHODS: We reviewed 21 patients diagnosed with HNSCC of the PNSNC who were treated with IC. We analyzed response, eyeball preservation rate, and overall survival. RESULTS: Tumors were located in the paranasal sinus (n = 14) or nasal cavity (n = 7). Most patients had stage T4a (n = 10) or T4b (n = 7) disease. More than half of the patients received a chemotherapy regimen of docetaxel, fluorouracil, and cisplatin (n = 11). Thirteen patients (61.9%) achieved a partial response after IC and 15 patients (71.4%) achieved T down-staging. Among 17 patients with stage T4 disease, which confers a high risk of orbital exenteration, 14 (82.4%) achieved preservation of the involved eye. The 3-year overall survival (OS) rate of patients who achieved a partial response to IC was 84.6%. The 3-year OS rate of patients with stable disease or disease progression after IC was 25.0% (p = 0.038). CONCLUSIONS: IC could be considered for down-staging patients with advanced T-stage disease. It could also be a reasonable option for eyeball preservation in locally advanced HNSCC of the PNSNC.

VEGF and Ki-67 Overexpression in Predicting Poor Overall Survival in Adenoid Cystic Carcinoma / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: The purpose of this study was to evaluate potential prognostic factors in patients with adenoid cystic carcinoma (ACC). MATERIALS AND METHODS: A total of 68 patients who underwent curative surgery and had available tissue were enrolled in this study. Their medical records and pathologic slides were reviewed and immunohistochemistry for basic fibroblast growth factor, fibroblast growth factor receptor (FGFR) 2, FGFR3, c-kit, Myb proto-oncogene protein, platelet-derived growth factor receptor beta, vascular endothelial growth factor (VEGF), and Ki-67 was performed. Univariate and multivariate analysis was performed for determination of disease-free survival (DFS) and overall survival (OS). RESULTS: In univariate analyses, primary site of nasal cavity and paranasal sinus (p=0.022) and Ki-67 expression of more than 7% (p=0.001) were statistically significant factors for poor DFS. Regarding OS, perineural invasion (p=0.032), high expression of VEGF (p=0.033), and high expression of Ki-67 (p=0.007) were poor prognostic factors. In multivariate analyses, primary site of nasal cavity and paranasal sinus (p=0.028) and high expression of Ki-67 (p=0.004) were independent risk factors for poor DFS, and high expression of VEGF (p=0.011) and Ki-67 (p=0.011) showed independent association with poor OS. CONCLUSION: High expression of VEGF and Ki-67 were independent poor prognostic factors for OS in ACC.

Is There Any Age Cutoff to Treat Elderly Patients with Head and Neck Cancer? Comparing with Septuagenarians and Octogenarians

With the increase in life expectancy, age is no longer considered as a limitation for treatment. Nevertheless, the treatment of elderly patients with head and neck cancer (HNC) remains controversial. Here, we aimed to review our experience with the treatment for elderly patients, while particularly focusing on the differences among older old patients (septuagenarians vs. octogenarians). We retrospectively reviewed the records of 260 elderly patients who were assigned to 3 groups according to age: 70 years old ≤ group 1 < 75 years old, 75 years old ≤ group 2 < 80 years old, and group 3 ≥ 80 years old. The patients were assessed for comorbidities using the Adult Comorbidity Evaluation (ACE)-27, and the American Society of Anesthesia (ASA) physical status was also compared. Group 1, 2, and 3, consisted of 97, 102, and 61 patients, respectively. No significant difference in demographic data was noted among the groups. However, group 3 showed more comorbidities than groups 1 and 2. With regard to the initial treatment for HNC, radiation therapy (RT) was more frequently performed in group 3 than in groups 1 and 2. Among 7 patients of non-compliant to treatment in group 3, 6 patients had have performed RT. In group 3, a total of 18 patients underwent surgery, including microvascular free flap reconstruction and no significant difference in complications was observed postoperatively compared with group 1 and 2. Moreover, no significant difference was noted in overall survival between the groups, regardless of the treatment modality chosen. In conclusion, octogenarians with HNC should be more carefully managed than septuagenarians with HNC. Surgical treatment can be considered in octogenarians with HNC, if it can be tolerated.

Is There Any Age Cutoff to Treat Elderly Patients with Head and Neck Cancer? Comparing with Septuagenarians and Octogenarians

With the increase in life expectancy, age is no longer considered as a limitation for treatment. Nevertheless, the treatment of elderly patients with head and neck cancer (HNC) remains controversial. Here, we aimed to review our experience with the treatment for elderly patients, while particularly focusing on the differences among older old patients (septuagenarians vs. octogenarians). We retrospectively reviewed the records of 260 elderly patients who were assigned to 3 groups according to age: 70 years old ≤ group 1 < 75 years old, 75 years old ≤ group 2 < 80 years old, and group 3 ≥ 80 years old. The patients were assessed for comorbidities using the Adult Comorbidity Evaluation (ACE)-27, and the American Society of Anesthesia (ASA) physical status was also compared. Group 1, 2, and 3, consisted of 97, 102, and 61 patients, respectively. No significant difference in demographic data was noted among the groups. However, group 3 showed more comorbidities than groups 1 and 2. With regard to the initial treatment for HNC, radiation therapy (RT) was more frequently performed in group 3 than in groups 1 and 2. Among 7 patients of non-compliant to treatment in group 3, 6 patients had have performed RT. In group 3, a total of 18 patients underwent surgery, including microvascular free flap reconstruction and no significant difference in complications was observed postoperatively compared with group 1 and 2. Moreover, no significant difference was noted in overall survival between the groups, regardless of the treatment modality chosen. In conclusion, octogenarians with HNC should be more carefully managed than septuagenarians with HNC. Surgical treatment can be considered in octogenarians with HNC, if it can be tolerated.

Long-Term Outcome of Definitive Radiotherapy for Early Glottic Cancer: Prognostic Factors and Patterns of Local Failure / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This study evaluates the long-term results of definitive radiotherapy (RT) for early glottic cancer. Clinical and treatment factors related to local control and patterns of failure are analyzed. MATERIALS AND METHODS: We retrospectively reviewed 222 patients with T1-2N0 squamous cell carcinoma of the glottic larynx treated with definitive RT from 1981 to 2010. None of the patients received elective nodal RT or combined chemotherapy. The median total RT dose was 66 Gy. The daily fraction size was < 2.5 Gy in 69% and 2.5 Gy in 31% of patients. The RT field extended from the hyoid bone to the cricoid cartilage. RESULTS: The median age was 60 years, and 155 patients (70%) had T1 disease. The 5-year rates of local recurrence-free survival (LRFS) and ultimate LRFS with voice preservation were 87.8% and 90.3%, respectively. T2 (hazard ratio [HR], 2.30; 95% confidence interval [CI], 1.08 to 4.94) and anterior commissural involvement (HR, 3.37; 95% CI, 1.62 to 7.02) were significant prognostic factors for LRFS. In 34 patients with local recurrence, tumors recurred in the ipsilateral vocal cord in 28 patients. There were no contralateral vocal cord recurrences. Most acute complications included grade 1-2 dysphagia and/or hoarseness. There was no grade 3 or greater chronic toxicity. CONCLUSION: Definitive RT achieved a high cure rate, voice preservation, and tolerable toxicity in early glottic cancer. T2 stage and anterior commissural involvement were prognostic factors for local control. Further optimization of the RT method is needed to reduce the risk of ipsilateral tumor recurrence.

A Case of Tracheal Foreign Body Removed by Endoscopic Approach with Tracheotomy / 대한이비인후과학회지

Foreign body (FB) airway obstruction is a life-threatening clinical situation. The FB's are removed by bronchoscopy in the majority of patients, but in highly-selected cases, tracheotomy is occasionally indicated in foreign body extraction, when they are subglottic in location and impacted, or large enough to get obstructed at the glottic chink during endoscopic removal. Authors report one case of tracheal FB which required tracheotomy for the FB removal after the failure of FB removal with rigid bronchoscopy.

A Convenient and Less Invasive Technique of Labial Minor Salivary Gland Biopsy Using a Minimal Incision With a Needle Tip

OBJECTIVES: This study was to show the technique and to compare the usefulness and complications of biopsy using a minimal incision with a needle tip of the labial minor salivary glands with those of conventional incisional lip biopsy in the diagnosis of Sjogren's syndrome. METHODS: We retrospectively reviewed the medical records of the patients who had the labial minor salivary gland biopsy for the diagnosis of Sjogren's syndrome between January 2005 and December 2008. One hundred forty-three patients were enrolled in this study. The yields of diagnostic salivary tissues and complications of the biopsy using a minimal incision with a needle tip and the conventional incisional lip biopsy were compared. RESULTS: Out of 143 patients, 56 patients underwent the conventional incisional lip biopsy and 87 patients received the biopsy using a minimal incision with a needle tip. In the biopsy using a minimal incision with a needle tip group, adequate salivary gland tissues were obtained in 85 patients out of 87 patients (97.7%). In the conventional incisional lip biopsy group, adequate specimens were acquired in 44 patients out of 56 patients (78.6%). There was no complication after the biopsy using a minimal incision with a needle tip, whereas there was one patient complained transient numbness of the lip after the conventional incisional lip biopsy. CONCLUSION: The less invasive labial minor salivary gland biopsy using a minimal incision with a needle tip was easy to perform and safe and showed the better result than the conventional incisional lip biopsy in terms of the adequate specimen in the diagnosis of Sjogren's syndrome. So it might be a good alternative to the conventional incisional lip biopsy.

Patterns of Regional Metastasis in Patients with Periorbital Cancer / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: To identify patterns of regional metastasis according to primary tumor location in patients with malignant periorbital tumor. SUBJECTS AND METHOD: We retrospectively reviewed the medical records of the patients diagnosed with periorbital malignant tumors between 1997 and 2008. We analyzed demographic data, pathologic diagnosis, primary tumor location, lymph node metastasis and recurrences. RESULTS: Ninety-five patients with periorbital cancer were reviewed. Amongst them, 16 patients (M : F=7 : 9, mean age: 57.0 years) had regional metastasis. The follow-up duration of 16 patients was 46.2 months on the average. Nine tumors were located in the medial half, two tumors in the lateral half and five tumors in both halves. The parotid gland was the most common regional metastatic site regardless of primary tumor location, and whether or not medially located. CONCLUSION: The parotid gland lymph node group is crucial for medially located periorbital tumor as well as for laterally located one. Once a malignant periorbital tumor is diagnosed, the whole cervical and parotid lymph nodes should be evaluated carefully.

Reconstruction of Maxilla and Midface with Microvascular Free Flaps / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: The aim of this study is to report the clinical results of maxillary reconstruction with free flap. SUBJECTS AND METHOD: Patients who had undergone free flap reconstruction after maxillectomy from January 2009 to January 2013 were included in the study. The medical records of the maxillary defect classification, the type of flap used for reconstruction, follow-up results including the survival rate of flap and postoperative complications were analyzed retrospectively. RESULTS: A total of 13 cases underwent maxillary reconstruction after maxillectomy. Maxillary resection were classified from Ia to V according to the Brown classlification system, and various composite flaps including rectus abdominis, latissimus dorsi, radial forearm and iliac crest were used. One case (class Ia) was reconstructed with a radial forearm free flap while six cases (classes II, III) were reconstructed with the osteomuscular free flap type, such as iliac crest. Another six cases needed orbital exenteration (class IV, V) and were reconstructed with a soft tissue free flap type, such as a rectus abdominis or latissimus dorsi. Of the 13 cases, four patients had postoperative wound dehiscence and two had preoperative radiotherapy. In all 13 cases, the flaps survived. CONCLUSION: Maxillary reconstructions were performed successfully with various free flaps according to the extent of maxillary defect.

Human salivary gland stem cells ameliorate hyposalivation of radiation-damaged rat salivary glands

Salivary function in mammals may be defective for various reasons, such as aging, Sjogren's syndrome or radiation therapy in head and neck cancer patients. Recently, tissue-specific stem cell therapy has attracted public attention as a next-generation therapeutic reagent. In the present study, we isolated tissue-specific stem cells from the human submandibular salivary gland (hSGSCs). To efficiently isolate and amplify hSGSCs in large amounts, we developed a culture system (lasting 4-5 weeks) without any selection. After five passages, we obtained adherent cells that expressed mesenchymal stem cell surface antigen markers, such as CD44, CD49f, CD90 and CD105, but not the hematopoietic stem cell markers, CD34 and CD45, and that were able to undergo adipogenic, osteogenic and chondrogenic differentiation. In addition, hSGSCs were differentiated into amylase-expressing cells by using a two-step differentiation method. Transplantation of hSGSCs to radiation-damaged rat salivary glands rescued hyposalivation and body weight loss, restored acinar and duct cell structure, and decreased the amount of apoptotic cells. These data suggest that the isolated hSGSCs, which may have characteristics of mesenchymal-like stem cells, could be used as a cell therapy agent for the damaged salivary gland.