Gene testing is performed to identify 1) viral or bacterial genes, 2) somatic mutations, 3) germline mutations and 4) polymorphisms. Purposes of gene testing for malignant tumors is to diagnose disease or to predict prognosis, treatment effects, or unwanted adverse effects. HPV status is an indispensable factor for determining the optimal therapeutic strategy for patients with oropharyngeal cancer (OPC). The identification of EBV and HPV in metastatic lymph nodes is now mandatory to determine the primary site. CRT1-MAML2 fusion gene is strongly associated with mucoepidermoid carcinoma with a favorable prognosis. Tyrosine kinase of RET is constantly activated in RET/PTC somatic rearrangements, which leads to the development of papillary thyroid carcinoma. More than 90% of synovial sarcoma has a chromosomal translocation of t(X;18)(p11.2;q11.2), resulting in the fusion gene SYT-SSX. The anti-EGFR antibody, cetuximab, has little or no effect on tumors harboring KRAS mutation or certain genomic variants of EGFR, although these mutations are rare in head and neck cancer. A new risk-stratification strategy has been developed based on the type of RET gene mutation to inform the age at which prophylactic thyroidectomy should be performed in MEN2. Bilateral retinoblastoma (RB) and 15% of unilateral RB are expected to exhibit a germline RB1 mutation. Survivors of hereditary retinoblastoma have a higher risk of developing other cancers later in life. Multiple head and neck paragangliomas are common in patients with SDHD mutations, while malignant head and neck paraganglioma is mostly seen in patients with SDHB mutations. Heterozygous aldehyde dehydrogenase 2 contributes to a higher chance of esophageal cancer and OPC.

Langerhans cell histiocytosis is a disease of unknown cause, characterized by abnormal proliferation of Langerhans cells. It may manifest as functional disorders of the liver and spleen, and/or as osteolytic lesions. The temporal bone is occasionally affected by Langerhans cell histiocytosis. Lateralized tympanic membrane usually occurs after operations on the external auditory canal or middle ear, or in association with injury and inflammation of the external ear. It may sometimes cause medial meatal fibrosis (MMF). A case of transcanal endoscopic ear surgery for lateralized tympanic membrane that arose as a complication after treatment of Langerhans cell histiocytosis is reported.

A patient was a 6-year-old boy who was brought to our hospital 4 years ago with intractable otorrhea on both sides. Biopsy of the tumor detected in the external auditory canal revealed the diagnosis of Langerhans cell histiocytosis. Ahead CT revealed several mass lesions with bone destruction of the skull and soft-tissue shadows in the external auditory canals of both sides. The patient received chemotherapy at the Department of Pediatrics and enterd remission after four years of treatment. Subsequently, he suffered from binaural conductive hearing loss caused by a lateralized tympanic membrane. A repeat CT showed soft-tissue shadows within both external auditory canals. We made the diagnosis of MMF developing after treatment for Langerhans cell histiocytosis. Transcanal endoscopic ear surgery was performed for the MMF on both sides, step-by step. An endoscope offers several advantages over a microscope: a wide field of view, higher magnification on close approach of the object, and clear visualization of structures that are hidden when a microscope is used. Thus, transcanal endoscopic ear surgery appears to be very useful for the treatment of the lateralized tympanic membrane, specifically for management around the tympanic annulus.

We report a rare case of neurofibroma of the nasal cavity, which is the 24th reported case in Japan. The patient was a 46-year-old man who presented to our hospital with nasal hemorrhage. Nasal endoscopy revealed a white mass in the nasal cavity. Computed tomography showed a tumor occupying the middle nasal meatus. We attempted biopsy multiple times, but could not confirm the diagnosis in the outpatient setting. We then performed endoscopic surgery and completely removed the tumor. Histopathology of the resected specimen revealed the diagnosis of neurofibroma of the nasal cavity. Because there are reports of recurrence and malignant change, careful follow-up is necessary.

Cough, one of the most common pediatric respiratory symptoms, could be caused by a variety of conditions. Rhinosinusitis is an important cause of chough in children. We analyzed the prevalence and characteristics of cough in 91 children (age 1–12 of years, 65 boys and 26 girls) clinically diagnosed as having rhinosinusitis. The chief complaint was rhinorrhea in 35%, cough in 13%, and nasal congestion in 12% of the subjects. The prevalence of cough was 64%, with the cough being productive in 95% of the casas. The average age was significantly lower and the proportion of cases with stridor significantly higher in the children with cough. Of all the subjects with rhinosinusitis, 13% reported postnasal drip as a subjective symptom; all of these children were five years or older. None of the children presented with postnasal drip as the chief complaint. There was no significant correlation between the presence of cough and the presence of subjective or objective postnasal drip. The mechanisms by which rhinosinusitis causes cough have not yet been precisely elucidated. Productive cough is a frequent and important symptom in children with rhinosinusitis. Accurate diagnosis and immediate treatment are necessary, especially for rhinosinusitis associated with cough.

In children and adolescents under 20 years of age, tumors of the parotid gland are relatively rare. A total of 14 patients with benign parotid tumors and 7 patients with malignant parotid tumors were treated at Osaka Medical College Hospital between 1999 and 2016. Pleomorphic adenoma was the most frequent benign neoplasm, while the most frequently encountered malignant neoplasm was mucoepidermoid carcinoma, followed by acinic cell carcinoma. Fine-needle aspiration cytology is useful and important for making a preoperative histological diagnosis, especially for benign tumors. Perioperative frozen section diagnosis is useful when there is doubt about whether the tumor is benign or malignant. Treatment is mainly surgery, with radiation therapy reserved for advanced-stage and/or histologically high-grade tumors. Parotid carcinoma in the pediatric age group is more often localized to the primary site and of low-grade histology than that in the adult population. Low- and intermediate-grade parotid carcinoma in the pediatric population may have favorable outcomes as compared to high-grade parotid carcinoma and adult parotid carcinoma.

PFAPA syndrome is characterized by five features: Periodic Fever, Aphthous stomatitis, Pharyngitis and cervical Adenitis, occurring in children under 5 years of age. Periodic fever, the main symptom, persists for about 3–6 days, accompanied by aphthous stomatitis, pharyngitis, neck lymphadenitis. We reviewed the data of two patients with PFAPA syndrome treated by tonsillectomy. In one patient, no improvement of the symptonms was obtained in response to treatment with a steroid and H2 blocker prescribed by a pediatrician, and tonsillectomy was performed; the patient has had no symptoms since this treatment.

The other patient wished to undergo tonsillectomy even before being initiated on any medications such as a steroid or H2 blocker. Both the patients who underwent tonsillectomy have shown a good course since the tonsillectomy.

We believe the tonsillectomy is feasible and effective in patients with the PFAPA syndrome.

Unilateral vocal cord paralysis appears to be a frequently encountered condition by otorhinolaryngologists, that often manifests as hoarseness or dysphagia. We encountered some cases that had recovered from unilateral vocal cord paralysis.

We studied the clinical features of patients who had recovered from unilateral vocal cord paralysis, by retrospectively analyzing the data of 135 patients who had been diagnosed as having unilateral vocal cord paralysis at our hospital between December 2010 and October 2015.

In the 135 patients enrolled in the study, the causes of the unilateral vocal cord paralysis were distributed as follows: idiopathic, 38 cases; postoperative, 42 cases; endotracheal intubation, 11 cases; tumor, 30 cases; others, 14 cases. A total of 41 of the 135 cases showed recovery from the paralysis, including 13 of the 38 cases with idiopathic paralysis (34.2%), 17 of the 42 with postoperative paralysis (40.5%), 10 of the 11 in whom the paralysis developed following endotracheal intubation (90.9%), and one of the 30 in which the paralysis was caused by a tumor (3.3%); none of the 14 cases with vocal cord paralysis of other causes showed recovery from the paralysis.

In the cases with idiopathic unilateral vocal cord paralysis, almost complete recovery was noted within 9 months of the appearance of the first symptoms and within 6 months of the diagnosis. In cases with the vocal cord paralysis developing after surgery or endotracheal intubation, near-complete recovery was observed within 4 months of the diagnosis. In patients with postoperative unilateral vocal cord paralysis after thyroid surgery, the intraoperative hemorrhage tended to be less and the operative duration was shorter in the patients who recovered than in those who had permanent paralysis.

Our findings revealed that unilateral vocal cord paralysis developing as a result of endotracheal intubation has a good prognosis, whereas that caused by tumors has a poor prognosis. Surgical procedure for paralysis should be considered on the merits of each case, such as in cases with idiopathic paralysis not improving within 9 months of the appearance of the first symptoms and cases with postoperative paralysis not resolving within 4 months. In cases of paralysis developing after thyroid surgery, the volume of hemorrhage, operative duration and type of operative procedure were found to exert an influence on the likelihood of recovery from the postoperative vocal cord paralysis.

Solitary fibrous tumor (SFT) is a relatively rare myofibroblastic tumor involving the pleura and peritoneum in most cases. Recently, SFTs arising various sites of the body have been described. The 2013 WHO classification of tumors of soft tissue and bone defines SFT an intermediate-grade tumor that is benign. However, distant metastases have been reported in about 10% of cases.

We report a rare case of SFT of the neck. The patient was a 75-year-old female who presented with the complaint of swelling of the right neck. Her previous doctor suspected schwannoma and referred her to our center for operation. However, the findings of fine-needle aspiration biopsy, computed tomography and magnetic resonance imaging were atypical. Therefore, we performed resection of the tumor to obtain a final diagnosis. Histopathology of the resected tumor revealed the diagnosis of SFT. This case serves to emphasize that in the differential diagnosis of tumors of the neck, it is important to bear in mind the possibility of SFT.

Adenoid cystic carcinoma (ACC) is a rare malignant tumor of the head and neck. Although ACCs are usually slow-growing, local recurrences and distant metastases often occur, resulting in a poorer long-term prognosis. We examined the prognostic factors in patients with ACC. Data of 23 patients with ACC who were treated at our hospital between 1996 and 2015 were reviewed retrospectively. The patients consisted of 10 males and 13 females, with a mean age of 59 years. The primary tumor site was the major salivary gland in 18 patients, oropharynx in 2 patients, nasal cavity in 2 patients, and oral mucosa in 1 patient. There were some cases in which it was difficult to diagnose ACC preoperatively. The overall survival rate was 82% at 5 years, and 47% at 10 years. The disease-specific survival rate was 82% at 5 years, and 65% at 10 years. Metastasis to the cervical lymph nodes and distant metastases were identified as poor prognostic factors. Since ACC shows diverse clinical manifestations, it is necessary to accumulate a greater number of cases to establish appropriate treatment modalities.