Two cases of parapharyngeal space tumor resected by a double split mandibular osteotomy technique.

Parapharyngeal space tumors have poor subjective symptoms and often grow until diagnosed; therefore, mandibular transection may be needed to obtain a wider field of view during surgery. However, if a median lower lip incision is performed for the mandibular transection, esthetic problems occur after surgery. Here, we report two cases of parapharyngeal space tumors that were removed with a mandibular lateral segment-osteotomy technique without median lower lip incision to avoid esthetic problems. Case 1 was a 49-year-old woman. She was aware of a right tonsillar swelling, and an imaging test revealed a tumor lesion 60 mm in size in the right parapharyngeal space. Case 2 was a 40-year-old woman with an abnormal position of the uvula, and an imaging test showed the left parapharyngeal space tumor lesion 45 mm in size. Both cases were diagnosed as a pleomorphic adenoma, and surgery under general anesthesia was performed jointly with otolaryngology and oral surgery. The incision was performed from the lower part of the right auricle to the anterior part of the submandibular area. After the tumor resection, the mandible was repositioned, fixed by plates, and the intermaxillary fixation was performed with a surgical stent. In both cases, slight paralysis of the mandibular branch of the facial nerve and the mental nerve was observed after the operation, but they were improved immediately. One year after the operation, the plates were removed. There have been no recurrences until now.

Oncolytic activity of HF10 in head and neck squamous cell carcinomas.

Recent developments in therapeutic strategies have improved the prognosis of head and neck squamous cell carcinoma (HNSCC). Nevertheless, 5-year survival rate remains only 40%, necessitating new therapeutic agents. Oncolytic virotherapy entails use of replication-competent viruses to selectively kill cancer cells. We aimed to explore the potential of HF10 as an oncolytic virus against human or mouse HNSCC cell lines, and primary-cultured HNSCC cells. HF10 replicated well in all the HNSCC cells, in which it induced cytopathic effects and cell killing. Next, we investigated the oncolytic effects of HF10 in ear tumor models with human or mouse tumor cells. We detected HF10-infected cells within the ear tumors based on their expression of green fluorescent protein. HF10 injection suppressed ear tumor growth and prolonged overall survival. In the syngeneic model, HF10 infection induced tumor necrosis with infiltration of CD8-positive cells. Moreover, the splenocytes of HF10-treated mice released antitumor cytokines, IL-2, IL-12, IFN-alpha, IFN-beta, IFN-gamma, and TNF-alpha, after stimulation with tumor cells in vitro. The HF10-treated mice that survived their original tumor burdens rejected tumor cells upon re-challenge. These results suggested that HF10 killed HNSCC cells and induced antitumoral immunity, thereby establishing it as a promising agent for the treatment of HNSCC patients.

Regulatory T cells expressing abundant CTLA-4 on the cell surface with a proliferative gene profile are key features of human head and neck cancer.

FOXP3+ regulatory T (Treg) cells suppress anti-tumor immunity. The suppression of Treg cells is regulated by cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), whose expression on the cell surface is tightly regulated. Here we found that Treg cells expressing abundant CTLA-4 on the cell surface (surface-CTLA-4+ Treg) were expanded in human head and neck cancer tissues. RNA sequencing of surface-CTLA-4+ and surface-CTLA-4- Treg cells infiltrating human head and neck cancer tissues revealed that surface-CTLA-4+ Treg cells have a previously undescribed gene expression profile correlating to cell cycle, cell proliferation, and DNA replication. Moreover, surface-CTLA-4+ Treg cells were PD-1+ , actively proliferated and associated with CD45RA- FOXP3high Treg cells with strong suppressive function. Thus, surface-CTLA-4+ Treg cells with a proliferative gene expression signature and phenotype are key features of head and neck cancer. Targeting surface-CTLA-4+ Treg cells might be new strategies to evoke effective immune responses to head and neck cancer.

Postoperative radiotherapy for T1/2N0M0 mucoepidermoid carcinoma positive for CRTC1/3-MAML2 fusions.

BACKGROUND: The National Comprehensive Cancer Network (NCCN) guidelines recommend considering postoperative radiotherapy (PORT) for completely resected T1/2N0M0 salivary mucoepidermoid carcinomas when they show tumor spillage, perineural invasion, or intermediate/high-grade histology. CRTC1/3-MAML2 fusions have been associated with a favorable clinical outcome. METHODS: Forty-seven T1/2N0M0 mucoepidermoid carcinoma cases positive for CRTC1/3-MAML2 fusions were completely resected and were not treated with PORT. RESULTS: Pathologically, none of the cases showed tumor spillage or perineural invasion. Cases with intermediate/high-grade histology numbered 9 (19%) to 26 (55%) with the currently used 3 different grading systems. During the follow-up (median 60 months), locoregional tumor recurrence occurred in 4 cases, which were treated with surgery alone. At the last follow-up (median 60 months; 7-160), all patients were alive with no evidence of disease. CONCLUSION: An excellent prognosis may be achieved without PORT in T1/2N0M0 mucoepidermoid carcinoma patients positive for CRTC1/3-MAML2 fusions when the tumors are completely resected without tumor spillage.

Mutation analysis of the EGFR pathway genes, EGFR, RAS, PIK3CA, BRAF, and AKT1, in salivary gland adenoid cystic carcinoma.

Adenoid cystic carcinoma (AdCC), one of the most common salivary gland carcinomas, usually has a fatal outcome. Epidermal growth factor receptor (EGFR) pathway gene mutations are important in predicting a patient's prognosis and estimating the efficacy of molecular therapy targeting the EGFR pathway. In this study of salivary gland AdCC (SAdCC), we looked for gene mutations in EGFR, RAS family (KRAS, HRAS, and NRAS), PIK3CA, BRAF, and AKT1, using a highly sensitive single-base extension multiplex assay, SNaPshot. Out of 70 cases, EGFR pathway missense mutations were found in 13 (18.6%): RAS mutations in 10 (14.3%), EGFR in one (1.4%), and PIK3CA in 5 (7.1%). None of the cases showed an EGFR deletion by direct sequencing. Concurrent gene mutations were found in three cases (4.3%). EGFR pathway mutations were significantly associated with a shorter disease-free (p = 0.011) and overall survival (p = 0.049) and RAS mutations were as well; (p = 0.010) and (p = 0.024), respectively. The gene fusion status as determined by a FISH assay had no significant association with mutations of the genes involved in the EGFR pathway. In conclusion, EGFR pathway mutations, especially RAS mutations, may be frequent in SAdCC, and associated with a poor prognosis for the patient.

Recurrent plexiform schwannoma involving the carotid canal.

Plexiform schwannoma (PS) is a rare variety of benign nerve sheath tumor characterized by a multinodular plexiform growth pattern. PS is usually confined to the head and neck or skin. The pre-operative diagnosis of PS is difficult, and this has lead to a common misdiagnosis as a schwannoma. In addition, studies have indicated that an incomplete resection of PS often results in tumor recurrence. Here we describe a rare case of PS presented in the parapharyngeal space. Our case involved a 36-year-old man with swelling of the pharynx, who presented with a soft cervical mass. MRI revealed a multinodular mass in the left parapharyngeal space, and further pathological diagnosis by the referral hospital indicated schwannoma. A cervical approach was taken and the tumor was removed with preservation of the nerve sheath by intracapsular resection. The tumor recurred within one year after the first surgery in the same lesion of the left parapharyngeal space. The second surgical approach was a combination of a facial dismasking flap and trans-pterygopalatine fossa. The mass was resected completely, and the diagnosis of PS was confirmed by histopathology. While schwannoma commonly occurs in the head and neck, parapharyngeal space PS is rare, and pre-operative pathological diagnosis of PS is difficult. MRI studies of PS revealed distinctive features that we found useful in pre-operative diagnosis. Intracapsular resection of PS with nerve preservation has a very high recurrence rate of the tumor. Therefore, if MRI findings suggest PS we recommend removing the tumor completely without nerve preservation will offer the most curative outcome.

Chemo-selection with docetaxel, cisplatin and 5-fluorouracil (TPF) regimen followed by radiation therapy or surgery for pharyngeal and laryngeal carcinoma.

BACKGROUND: Induction chemotherapy for patients with head and neck cancer is widely performed, and several advantages of induction chemotherapy have been reported. However, there is currently insufficient evidence to strongly recommend induction chemotherapy. In this study, we analyzed the outcomes for patients treated with induction chemotherapy and subsequent definitive treatments. METHODS: Operable patients with untreated oropharyngeal, hypopharyngeal and laryngeal squamous cell carcinoma treated with induction chemotherapy were included in this retrospective study. We conducted induction chemotherapy using docetaxel, cisplatin and 5-fluorouracil and performed subsequent surgical treatment or radiotherapy according to the response to induction chemotherapy. RESULTS: A total of 65 patients were included in this study, and 50 patients (76.9%) had Stage IV tumors. The response to induction chemotherapy was CR in two patients, PR in 55 patients, and SD in eight patients. The subsequent definitive treatment was radiotherapy in 60 patients, and surgery in five patients. The 3-year overall survival rates for patients who received radiotherapy and surgery were 88.4% and 75.0%, respectively (P = 0.30). The 3-year disease-free survival rates for patients who received radiotherapy and surgery were 68.0% and 0%, respectively (P = 0.01). The 3-year laryngeal dysfunction free survival rates for patients who received RT and surgery were 77.8% and 0%, respectively (P < 0.01). CONCLUSIONS: We achieved favorable survival outcomes and high larynx preservation rates. Our results suggest that induction chemotherapy using TPF regimen is one of the optimal treatment strategies when treating head and neck cancers. Further prospective studies with a larger cohort are required to confirm our findings.

Monitoring of recurrent and superior laryngeal nerve function using an Airwayscope™ during thyroid surgery.

In thyroid surgery, intraoperative identification and preservation of the recurrent laryngeal nerve (RLN) and superior laryngeal nerve external branch (SLNEB) are crucial. Several reports have proposed that electromyography (EMG) monitoring is an acceptable adjunct for identification and preservation of the RLN. However, a limited number of hospitals have access to an EMG monitoring system. Therefore, the development of another viable monitoring method is required. The aim of the present study was to design a new RLN and SLNEB monitoring method combining an Airwayscope™ (AWS) and a facial nerve stimulator. The facial nerve-stimulating electrode stimulates the RLN or SLNEB, so that the movement of the vocal cord may be observed with an AWS. This monitoring method was performed on 10 patients with a thyroid tumor. In all the cases, RLN and SLNEB were identified and vocal cord function was preserved. All the patients exhibited normal vocal cord function following surgery. Thus, the new RLN and SLNEB monitoring method using an AWS and a facial nerve stimulator is useful in thyroid surgery, and this method may be used as a reliable and available alternative to EMG monitoring to ensure the normal function of the vocal cord.

Dermopathy associated with cetuximab and panitumumab: investigation of the usefulness of moisturizers in its management.

AIMS: Limited data regarding the objective evaluation of skin exsiccation caused by epidermal growth factor receptor (EGFR) inhibitors exist. Objective indices were applied to evaluate the usefulness of a moisturizer against skin exsiccation associated with the use of EGFR inhibitors in cancer patients. PATIENTS AND METHODS: Patients with either colorectal or head and neck cancer treated with either cetuximab or panitumumab were randomly assigned 1:2 to the prophylactic-treatment arm, where participants received prophylactical moisturizer treatment (heparinoid preparation, Hirudoid®), or to the symptomatic-treatment arm, where moisturizer was applied after the onset of cutaneous symptoms. Patients were observed for 6 weeks after the start of the administration of EGFR inhibitor. RESULTS: A total of 15 patients were included and assessed: 6 in the prophylactic treatment group and 9 in the symptomatic treatment group. We evaluated the effect of EGFR inhibitors on the physiologic function of the skin. Administration of EGFR inhibitors resulted in a continued reduction in the moisture content of the horny layer and a decrease in cutaneous sebum levels. Skin observation revealed frequent development of an acneiform rash and significantly higher exsiccation and exfoliation scores. Administration of EGFR inhibitor was associated with a decrease in the horny layer moisture content and lower cutaneous sebum levels in the symptomatic treatment group. In contrast, levels of both the indicators were increased in the prophylactic treatment group. Moreover, the EGFR inhibitor-associated increase in exsiccation and exfoliation scores were minimized in the prophylactic treatment group relative to the symptomatic treatment group. CONCLUSION: Application of a moisturizer is effective against dry skin induced by the administration of an EGFR inhibitor.

Surgical treatment of parapharyngeal space tumors: A report of 29 cases.

The present study aimed to establish a strategy for parapharyngeal space (PPS) tumor surgery based on preoperative symptoms, clinical signs, imaging and histological examination. A retrospective cohort study was conducted with 29 adult patients who underwent surgery for primary PPS tumors from 2008-2015. The following data was obtained: Preoperative symptoms of the patient, histological type of the tumor, surgical approach and complications. Of the 29 patients who underwent surgery to remove a PPS tumor, 16 presented with neurogenic tumors and 13 with salivary gland tumors. The most common symptom was the presence of a neck mass. Preoperative computed tomography and magnetic resonance imaging were performed to evaluate the size and location of the tumors. The majority of the salivary gland tumors were located in the prestyloid space, whereas all neurogenic tumor cases were poststyloid. A total of 21 of the 29 patients (72.4%) underwent a preoperative fine needle aspiration (FNAC) examination. FNAC contributed to preoperative diagnosis in 9 of these cases (42.9%). In parotid tumors of the prestyloid space, facial nerve palsy was a common postoperative complication. In the case of neurogenic tumors, a common complication was the postoperative palsy of the nerve of tumor origin. The strategy for PPS surgery, from the preoperative diagnosis to the operative method, remains controversial. The data on pre- and postoperative symptoms, imaging and histological diagnosis, and the selection of surgical method depending on a neurogenic or salivary tumor origin in the present study indicated that improving the method of examination, carefully selecting the method of approach and accurately managing surgery leads to complete tumor removal, and that the use of nerve-preserving techniques may reduce the likelihood of complications.

MYB, MYBL1, MYBL2 and NFIB gene alterations and MYC overexpression in salivary gland adenoid cystic carcinoma.

AIMS: Adenoid cystic carcinoma (AdCC) is one of the most common salivary gland malignancies and the long-term prognosis is poor. In this study, we examined alterations of AdCC-associated genes, MYB, MYBL1, MYBL2 and NFIB, and their target molecules, including MYC. The results were correlated to clinicopathological profile of the patients. METHODS AND RESULTS: Using paraffin tumour sections from 33 cases of salivary gland AdCC, we performed a detailed fluorescence in-situ hybridization (FISH) analysis for gene splits and fusions of MYB, MYBL1, MYBL2 and NFIB. We found that 29 of 33 (88%) AdCC cases showed gene splits in either MYB, MYBL1 or NFIB. None of the cases showed an MYBL2 gene alteration. AdCCs were divided genetically into six gene groups, MYB-NFIB (n = 16), MYB-X (n = 4), MYBL1-NFIB (n = 2), MYBL1-X (n = 1), NFIB-X (n = 6) and gene-split-negative (n = 4). AdCC patients showing the MYB or MYBL1 gene splits were associated with microscopically positive surgical margins (P = 0.0148) and overexpression of MYC (P = 0.0164). MYC expression was detected in both ductal and myoepithelial tumour cells, and MYC overexpression was associated with shorter disease-free survival of the patients (P = 0.0268). CONCLUSIONS: The present study suggests that (1) nearly 90% of AdCCs may have gene alterations of either MYB, MYBL1 or NFIB, suggesting the diagnostic utility of the FISH assay, (2) MYB or MYBL1 gene splits may be associated with local aggressiveness of the tumours and overexpression of MYC, which is one of the oncogenic MYB/MYBL1 targets and (3) MYC overexpression may be a risk factor for disease-free survival in AdCC.

Striated duct adenoma presenting with intra-tumoral hematoma and papillary thyroid carcinoma-like histology.

Striated duct adenoma of the salivary gland is a rare benign tumor characterized by unilayered duct epithelium and striations of the tumor cell membranes. To the best of our knowledge, only six cases have been reported in the literature. Here we report an additional case, which was complicated by an intra-tumoral hematoma on clinical presentation and by papillary thyroid carcinoma-like histology on intra-operative frozen section diagnosis. An asymptomatic 78-year-old male presented with a two-year-history of a painless tumor of the left parotid. An intra-tumoral hematoma, which is unusual for a salivary gland tumor, was suspected from results of pre-operative radiology. The patient then underwent a left parotidectomy. The intra-operative frozen section diagnosis indicated a benign tumor, although ectopic papillary thyroid carcinoma was raised as a differential diagnosis since the eosinophilic tumor cells occasionally possessed nuclear grooves and nuclear pseudo-inclusions. By precise histopathological examination using paraffin sections, the tumor was finally diagnosed as striated duct adenoma. This type of tumor has unique features of hypervascular stroma and papillary thyroid carcinoma-like nuclei. In our case, the former feature was associated with the intra-tumoral hematoma and the latter feature, with difficulty in frozen section tumor diagnosis.

Expression of cancer/testis antigens in salivary gland carcinomas with reference to MAGE-A and NY-ESO-1 expression in adenoid cystic carcinoma.

AIMS: Cancer/testis antigens (CTAs) are detected in cancer cells but not in healthy normal tissues, with the exception of gametogenic tissues. CTAs are highly immunogenic proteins, and thus represent ideal targets for cytotoxic T-lymphocyte-mediated specific immune therapy. The aim of this study was to screen CTA expression in various types of salivary gland carcinoma and to clarify clinicopathological significance of MAGE-A and NY-ESO-1 expression in adenoid cystic carcinomas (AdCCs) of the salivary gland, which is one of the most common salivary gland carcinomas, and usually has a fatal outcome. METHODS AND RESULTS: We used immunohistochemistry to examine the expression of four CTAs (MAGE-A, NY-ESO-1, CT7, and GAGE7) in various types of salivary gland carcinoma (n = 95). When carcinoma cases were divided into low-grade and intermediate/high-grade types, NY-ESO-1 and CT7 were expressed more frequently in intermediate/high-grade carcinomas. We then focused on MAGE-A and NY-ESO-1 expression in a large cohort of adenoid cystic carcinomas (AdCCs) (n = 46). MAGE-A and NY-ESO-1 were frequently expressed in AdCC; specifically, MAGE-A was expressed in >60% of the AdCC cases. MAGE-A expression and tumour site (minor salivary gland) were identified as independent risk factors for locoregional tumour recurrence. CONCLUSIONS: These findings suggest that CTAs may be expressed in a variety of salivary gland carcinomas, especially in those with higher histological grades. In addition, MAGE-A, which is frequently expressed in AdCC cases, may be a useful prognostic factor for poorer locoregional recurrence-free survival.

Treatment results of alternating chemoradiotherapy with early assessment for advanced laryngeal cancer: A multi-institutional phase II study.

OBJECTIVE: To evaluate the efficacy and safety of alternating chemoradiotherapy (ACRT) with early assessment of advanced laryngeal cancer. METHODS: Patients with stage III or IV glottic or supraglottic squamous cell carcinoma were enrolled. ACRT consisted of two cycles of chemotherapy involving 5-fluorouracil and cisplatin (weeks 1 and 6) and radiotherapy (RT; weeks 2 and 7) administered alternately. An early assessment was performed after one cycle of chemotherapy and RT. Patients with a partial response (PR) or a complete response at early assessment continued ACRT. Patients with stable disease (SD) or progressive disease at early assessment discontinued ACRT and underwent salvage surgery. After completion of ACRT, patients who had residual primary tumor and lymph metastasis underwent salvage surgery. RESULTS: Twenty-eight patients were enrolled in this trial. Median follow-up was 60.0 months. After each cycle of chemotherapy and RT, 24 of the 28 patients (85.7%) were assessed as having a PR at early assessment and continued ACRT, and 4 of 28 patients (14.3%) who were assessed as having SD at early assessment discontinued ACRT and underwent salvage surgery. The estimated 5-year local control and 5-year survival rates were 49.0% and 77.4%, respectively. Larynx preservation was achieved in 17 patients. The estimated 5-year laryngeal preservation rate was 59.4%. Major toxicity included nausea, stomatitis, dermatitis, dysphagia and hemoglobin toxicity. Grade 3 or 4 stomatitis occurred in three patients (10.7%). CONCLUSION: The clinical results of ACRT with early assessment of advanced laryngeal cancer patients showed sufficient efficacy and safety.

Functional Nerve Preservation in Extracranial Head and Neck Schwannoma Surgery.

IMPORTANCE: A schwannoma is an uncommon, benign neurogenic tumor of Schwann cells. Tumor enucleation is the recommended surgical method to preserve function of the original nerve, although enucleation does not guarantee completely intact nerve function after the operation. OBJECTIVE: To establish a strategy for functional preservation in extracranial head and neck schwannoma treatment by using an electromyographic (EMG) system during tumor resection. DESIGN, SETTING, AND PARTICIPANTS: A retrospective cohort study was conducted of 15 patients who underwent surgery for removal of schwannoma tumors between April 1, 2006, and March 31, 2015, at an academic tertiary referral center. Data analysis was conducted from April 3, 2006, to September 15, 2015. Neurogenic tumors were diagnosed according to preoperative findings, and during surgery tumors were exposed and given EMG-controlled electrical stimulation to analyze their origins. In motor nerve cases, the electrical activity of the muscle was measured and recorded by EMG. The tumor was then enucleated by incision along tumor fibers mapped using EMG stimulation. If a nerve bundle was visible, we incised along there and enucleated the tumor. INTERVENTIONS: A strategy using electrical stimulation to improve preservation of nerve function in extracranial head and neck schwannoma operations. MAIN OUTCOMES AND MEASURES: Frequency and duration of postoperative neurologic complications associated with functional preservation surgery with tumor enucleation was evaluated using EMG monitoring according to tumor origin. RESULTS: Of the 15 patients with extracranial schwannoma, 9 (60%) were women (mean [SD] age, 36.3 [15.3] years). All 15 patients underwent surgery using a transcervical approach. The most common nerves of origin were the vagus nerve and the sympathetic chain. In sensory or sympathetic nerve cases, the EMG response was absent. Two of 5 patients with vagus schwannoma had postoperative temporary vocal nerve palsy. These symptoms showed improvement after 1 year. There was no tumor recurrence during the follow-up period in any patient. CONCLUSIONS AND RELEVANCE: The strategy used here demonstrated a method of diagnosis and nerve preservation surgery for extracranial schwannomas. Nerve functionality was preserved in all vagus schwannoma cases. However, preservation of nerve function in sympathetic nerve schwannoma cases remains problematic and needs further investigation.

A peripheral primitive neuroectodermal tumor in the larynx: A case report and literature review.

Primitive neuroectodermal tumors (PNETs) are malignant tumors comprised of small round cells of neuroectodermal origin. Current evidence indicates that peripheral PNETs (pPNETs), which arise in the non-central nervous system, possess histological similarity to Ewing's sarcoma. Though the occurrence of pPNETs in the head and neck region is rare, these are aggressive malignant tumors, and long-term survival rates following diagnosis remain poor. The current report presents a case of pPNET and evaluates its significance with regard to previous studies. In the present case, a tumor was located in the larynx of the patient, and was diagnosed as pPNET. Immunohistochemical analysis indicated that tumor cells were positive for cluster of differentiation 99. The patient was treated with surgery, multiagent chemotherapy and radiotherapy. Five years subsequent to treatment, the patient had survived and demonstrated no evidence of disease recurrence. In existing literature concerning pPNET located outside the head and neck region, it is recommended that patients are treated with a combination of resection with a wide surgical margin, multiagent chemotherapy and radiotherapy. The present case report concluded that the combination of surgery, systematic chemotherapy and radiotherapy, offers an improved outcome for pPNET localized to the head and neck region, compared with any of these therapies alone.

Warthin-like Mucoepidermoid Carcinoma: A Combined Study of Fluorescence In Situ Hybridization and Whole-slide Imaging.

There has been some debate as to whether a subset of metaplastic Warthin tumors (mWTs) harbor the mucoepidermoid carcinoma (MEC)-associated CRTC1-MAML2 fusion. We analyzed 15 tumors originally diagnosed as mWT (mWT-like tumors), 2 of which had concurrent MECs. We looked for the CRTC1/3-MAML2 fusion transcripts and performed immunohistochemistry for p63 and fluorescence in situ hybridization (FISH) for the MAML2 split. To localize MAML2 split-positive cells at the cellular level, whole tumor tissue sections were digitalized (whole-slide imaging [WSI]). The CRTC1-MAML2, but not CRTC3-MAML2 was detected in 5/15 mWT-like tumors. FISH-WSI results showed that all epithelial cells harbored the MAML2 split in fusion-positive mWT-like tumors and were totally negative in fusion-negative mWT-like tumors. A review of the hematoxylin and eosin-stained slides showed that morphology of the "metaplastic" epithelium was virtually indistinguishable between fusion-positive and fusion-negative tumors. However, oncocytic bilayered tumor epithelium, characteristic to typical WT, was always found somewhere in the fusion-negative tumors but not in the fusion-positive tumors. This distinguishing histologic finding enabled 5 pathologists to easily differentiate the 2 tumor groups with 100% accuracy. The age and sex distribution of fusion-positive mWT-like tumor cases was similar to that of fusion-positive MEC cases and significantly different from those of fusion-negative mWT-like tumor and typical WT cases. In addition, only fusion-positive mWT-like tumors possessed concurrent low-grade MECs. In conclusion, a subset of mWT-like tumors were positive for the CRTC1-MAML2 fusion and had many features that are more in accord with MEC than with WT. The term Warthin-like MEC should be considered for fusion-positive mWT-like tumors.

A Technique for Preoperative Identification of the Facial Nerve Mandibular Branch Using a Nerve Stimulator.

We established the method of preoperative identification to facial nerve marginal mandibular branch (FNMB) identification using a nerve stimulator with bipolar probe for upper-neck surgery. The bipolar electrode is placed on the region while patients were awake; the patient should be in the same position and posture as during the surgery, with the neck skin stretched. A nerve course is confirmed by observing the movement of the lower lip. In this study, 5 upper-neck surgeries were conducted. Preoperative analysis revealed that 4 of the 5 cases had 2 branches of FNMB, and 1 with 3 branches. All FNMB immediately confirmed preoperatively were identified during surgery. We performed this method in much surgery including the surgery of the upper neck. It was easy to identify the facial nerve by this method and came to be able to do it precisely, and an operative time was shortened. We concluded that the preoperative FNMB identification using a nerve stimulator is most useful and benefit for upper-neck surgery patients and lead to avoid lower lip paralysis.

Androgen receptor-positive mucoepidermoid carcinoma: case report and literature review.

Androgen receptor (AR) is usually expressed in salivary duct carcinoma (SDC), but only infrequently in other carcinoma types including mucoepidermoid carcinoma (MEC). The clinicopathological characteristics of AR-positive MEC remain to be clarified. Here we report a case of AR-positive MEC. A 76-year-old man presented with a growing painless tumor of the right parotid. The resected tumor was a high-grade tumor with necroses. Since the tumor was positive for AR, GCDFP-15, and HER2, SDC was first suspected, but it was also positive for CK5/6 and P63, and negative for S-100 protein and α-smooth muscle actin. In addition, scattered mucous secreting tumor cells were found in the tumor nests, and they were positive for Alcian blue. A diagnosis of AR-positive MEC was finally made. The patient died of the tumor 5 years after the surgery. The present case may expand the histopathological spectrum of high-grade MEC.