Cervical schwannomas are relatively rare, and it is difficult for a single otolaryngologist or head and neck surgeon to experience many cases of this disease. When surgery is performed, there is a risk of neurological deficits, which discourages not only the patients themselves, but also the attending doctors, from opting for surgical treatment. The tumor is most commonly diagnosed in persons between 30 and 50 years of age, and since most patients have no symptoms other than a cervical mass, there are various views as to how these patients should be managed: whether to be followed up or operated upon, and if surgery is chosen, how the surgery is to be performed. Various surgical approaches have been reported to avoid postoperative neurological deficits. For example, the use of NBI to confirm the tumor capsule, the creation of a surgical model to understand the structure of the schwannoma, partial inter-capsular resection to reduce blood loss, and the continuous aspiration syringe technique for parapharyngeal space schwannomas have been reported. This article outlines the clinical aspects of cervical schwannomas based on our clinical experience.

Malignant melanoma of the external auditory canal (MMEAC) is rare. Herein, we report a case of malignant melanoma of the auditory canal. A 71-year-old woman visited our department with a 6-month history of perceiving a sense of discomfort in the left ear. Computed tomography (CT) and magnetic resonance imaging (MRI) showed a mass in the external auditory canal. A biopsy examination revealed the diagnosis of malignant melanoma. Proton beam therapy was selected for the treatment. The patient remained free of local recurrence/distant metastasis for a long period of time. However, 9 years after the treatment, he was diaganosed as having metastases in the upper left gum and brain, and is currently receiving chemotherapy.

We encountered a case of MMEAC in which we obtained good local control of the disease with proton beam therapy. Long-term follow up is necessary, because of the heightened risk of metastasis/recurrence in cases of malignant melanoma.

Malignant external otitis (MEO) is an intractable disease with a high mortality rate, despite advances in the development of antimicrobial agents. MEO mainly requires administration of antibiotics, local treatment, and strict management of diabetes mellitus, which takes a long time. We present 2 cases of MEO in elderly patients that were successfully treated by multidisciplinary collaboration. The two patients were referred to our department after conservative treatment failed to improve their condition. In both cases, remission was achieved with hospitalization and multidisciplinary treatment for diabetes mellitus, impaired renal function, activities of daily living (ADL), and cognitive function. As one of the factors contributing to the poor prognosis of MEO, treatment can often not be completed in the elderly, who are more likely to show deterioration of ADL and cognitive functions. In addition, MEO is often not well known, not only to patients, but also to physicians. Awareness of this disease and multidisciplinary treatment are essential to improve the outcomes of MEO.

Adequate measures to manage hemorrhage and liquorrhea are important for safe performance of mastoidectomy. While hemorrhage and liquorrhea from the middle cranial fossa are relatively frequently encountered during mastoidectomy, management of massive hemorrhage from the sigmoid sinus and liquorrhea from the posterior cranial fossa is often very challenging. Continuous liquorrhea can cause intra-cranial infections, such as meningitis and brain abscess.

Among the 880 patients who had undergone ear surgery with mastoidectomy for such conditions as chronic otitis media, cholesteatoma, and decompression of the facial nerve over a 20-year period at our instruction, we analyzed the surgical data of 33 cases that had developed hemorrhage and 20 cases that had developed liquorrhea during mastoidectomy.

Based on a review of the data, we consider that multilayer obliteration is more reliable than simple obliteration. There was one case each of pneumocephalus and meningitis developing as postoperative intracranial complications, and in both cases, the condition resolved with conservative treatment.

In the treatment of salivary gland cancer, radical resection with negative surgical margins is paramount in determining the patient’s prognosis, and therefore, the indication for concomitant resection of the facial nerve should be carefully considered, based on not only the findings on preoperative examination, but also on the intraoperative findings. We report a case of high-grade parotid carcinoma with positive surgical margins that resulted from discrepancies between the findings during preoperative treatment planning and the intraoperative findings, which led to a poor prognosis. In addition, histopathology revealed a rare tumor, namely, dedifferentiated epithelial myoepithelial carcinoma (EMC). Therefore, in this case report, we also review this rare disease entity. The patient was a 58-year-old man who presented with a swelling below the left ear that he had first noticed about 5 months prior to his first visit to our department, and he was referred to us with a suspected left parotid tumor. Physical examination revealed a hard mass with poor mobility below the left ear and multiple enlarged lymph nodes at levels II and III in the left cervical region. CT and MRI showed two irregular masses with poor enhancement within the left parotid gland, one 3.4 cm in diameter and the other 3.2 cm in diameter, and enlarged lymph nodes at levels I-III of the left neck. FDG-PET/CT showed accumulation in the same masses and in the left cervical enlarged lymph nodes. Core needle biopsy of the left parotid tumor revealed poorly differentiated carcinoma, and a total left parotidectomy was performed with left cervical dissection. Histopathology showed a bilayer of cuboidal cells with eosinophilic spherocytes inside and bright cells outside, and a focal and dense infiltrative growth of atypical cells containing enlarged nuclei with prominent nucleoli; based on the findings, we made the diagnosis of dedifferentiated EMC. Since the tumor resection margins were partially positive, and multiple metastases to the dissected lymph nodes and some extranodal invasion were also observed, radiation therapy (60 Gy) was added as adjuvant therapy. One year after the completion of radiotherapy, there was no apparent disease recurrence. Herein, we described a case of dedifferentiated EMC presenting as a high-grade parotid carcinoma. In the treatment of salivary gland carcinoma, radical resection with negative surgical margins is crucial in determining the patient’s prognosis. Therefore, the indication for resection of the facial nerve should be considered based on the distance between the facial nerve and the tumor, the tumor histology, and the malignancy grade of the salivary gland cancer, and sometimes it is considered necessary not to hesitate to perform resection of the facial nerve in order to achieve a complete resection. While some reports of cases of dedifferentiated EMC, which are considered to be very rare, have been published previously, a larger number of cases should be accumulated to further elucidate the characteristics of dedifferentiated EMC.

Mucosal pemphigus occurring in a background of malignant lymphoma is rare. The patient was a 68-year-old woman who presented with the chief complaints of oral pain and mucosal erosions, and a skin biopsy and blood tests were performed. Serology for anti-BP180, anti-Dsg1, and anti-Dsg3 antibodies was negative. Direct fluorescence testing revealed no IgG deposition, while indirect fluorescence testing revealed anti-basement membrane antibodies. Serology was positive for full-length BP180 ELISA and BP180-C-terminal, based on which we made the diagnosis of mucosal pemphigoid. CT showed a mediastinal tumor and pleural effusion. Pleurocentesis was performed, and a cell block was prepared. Based on the results of cytological examination, we made the diagnosis of diffuse large B-cell lymphoma. The patient was initiated on R-CHOP therapy, which resulted in improvement of the mucocutaneous eruption. She died in a hospice 18 months after the start of treatment. This patient presented as a case of mucosal pemphigoid associated with DLBCL. Mucosal pemphigus is relatively rarely associated with malignant diseases other than solid tumors. Autoimmune bullous disease would be initially suspected in patients presenting with oral mucocutaneous eruption. In addition, malignant tumors can also be associated with autoimmune blistering, and a systematic search should be performed.

Sinus cysts are epithelial cysts that contain thick mucus and are thought to be primarily caused by obstruction of the natural ostium of the sinus.

These cysts occur after sinus surgery in most cases, and primary sinus cysts are relatively rare, with only sporadic reports of their occurrence in children.

We treated a 12-year-old boy with a primary frontal sinus/ethmoid sinus cyst who visited our hospital with a history of headache, but no other symptoms such as proptosis or upper eyelid swelling. He had severe headaches and had been taking analgesics daily, so that we exteriorized the cyst via under an endonasal approach using an endoscope and drained yellowish effusion from the cyst.

Removal of the cyst wall revealed a single cavity up to the frontal sinus, so that we did not touch the frontal sinus. Pediatric endoscopic sinus surgery is necessary to set the surgical method and surgical scope taking into consideration the stage of growth.

If age-appropriate settings are made, subjective symptoms can be expected to improve. In this case, the headache disappeared immediately after the surgery, and no recurrence has been observed until date.

We report a case of sternocleidomastoid muscle and mediastinal abscesses developing as a complication of sternoclavicular joint arthritis, along with a brief review of the literature. A 67-year-old man presented to us with a history of left shoulder pain and neck pain. CT showed a large heterogeneous mass occupying the left sternocleidomastoid muscle, with a high-density area around the sternoclavicular joint. We performed drainage of the sternocleidomastoid muscle and anterior chest wall abscesses, and a tracheostomy. The patient was also diagnosed as having sepsis and received broad-spectrum antibiotic therapy. Cultures from both the neck abscess and blood grew Staphylococcus aureus. The abscess spread to the middle mediastinum by day 7 of hospitalization. Because of the neck and mediastinal abscesses, operation was performed a third time, along with antibiotic therapy. The purulent arthritis was treated conservatively. One month after the operation, the patient resumed oral intake, and after two months, he was discharged home. Herein, we report a case in which sternoclavicular joint arthritis was complicated by the formation of an abscess in the sternocleidomastoid muscle and a mediastinal abscess. Depending on individual cases, appropriate treatment may require multidisciplinary cooperation.

Salivary duct carcinoma (SDC), which is a rare and aggressive tumor of the salivary glands, is associated with a high likelihood of development of distant metastasis and local recurrence even from an early stage of the disease. No effective treatment for metastatic SDC has been established yet. Immunohistochemical studies have demonstrated the expression of androgen receptors (AR) at a high frequency in cases of SDC, and we considered that endocrine therapy targeting AR would be effective for cases of SDC. We present the case of an 81-year-old man with AR-positive submandibular gland SDC, with neck lymph node and multiple bone metastases. We judged that radical resection would be difficult, and initiated the patient on anti-androgen therapy with oral bicalutamide. After 5 months of bicalutamide treatment, PET-CT showed obvious decrease in the size of the submandibular gland tumor, neck lymph node metastases, and bone metastases. The patient was continued bicalutamide treatment for more than 12 months.

Bicalutamide treatment should be considered for patients with AR-positive SDC.

We performed surgical treatment for a Zenker’s diverticulum which carries the risk of postoperative recurrent laryngeal nerve palsy. The patient was a 71-year-old man who presented with a 6-year history of dysphagia that first developed after the patient underwent thyroid surgery, and was diagnosed as having Zenker’s diverticulum. At first, the patient did not wish to undergo surgery, but after he suffered several recurrent episodes of aspiration pneumonia, we decided to treat him by surgery after obtaining his consent. We performed the surgery under continuous intraoperative nerve monitoring to avoid recurrent laryngeal nerve palsy. The diverticulum was excised after cutting the cricopharyngeal muscle for the purpose of identifying the base of the diverticulum. The patient did not manifest any signs of recurrent laryngeal nerve palsy or any swallowing disorder postoperatively. However, as his swallowing function began to worsen, he was initiated on swallowing rehabilitation. The causes of postoperative deterioration of the swallowing function include disuse changes during the postoperative period of abstention of oral intake and laryngeal edema due to neck manipulation. The patient underwent swallowing rehabilitation and achieved the same level of swallowing function as before the surgery, and showed no evidence of recurrence. Zenker’s diverticulum is more frequently encountered in the elderly. Therefore, it is important to consider the surgical technique based on the risk of complications, such as disease recurrence and recurrent laryngeal nerve palsy.

We report a rare case of cervical vagal schwannoma in which we had difficulty in evaluating the vocal fold movements. The patient was a 52-year-old man diagnosed as having a cervical vagal schwannoma. We found it difficult to evaluate the vocal fold movements in this patient because he had a history of having undergone surgery for laryngotracheal injury sustained in a traffic accident. As the tumor increased in size, with consequent worsening of the pharyngeal discomfort reported by the patient, we performed intracapsular resection of the tumor. Intraoperative vagus nerve stimulation showed elicited no vocal cord response. However, the patient developed hiccups and bradycardia during the surgery, which suggested that the main afferent tract of the vagus nerve was still preserved. Therefore, the tumor was removed while taking care to preserve the vagus nerve, and no obvious neurological deficit was observed after the surgery. Thus, particular attention needs to be paid selection of the appropriate treatment strategy in such patients because of the risk of perioperative complications.

Schwannomas rarely occur in the neck, and despite their characteristic features on magnetic resonance imaging, it can be difficult to make a definitive diagnosis. In this report, we describe the case of a schwannoma of sympathetic nerve origin, which was diagnosed surgically after a thorough workup for a cystic tumor in the neck.

A 52-year-old man presented with a left cervical tumor. He had visited his previous doctor for a thorough examination of a mass in his left neck that he had become aware of 3 years prior to the first visit.

The differential diagnosis included branchial cyst, schwannoma, and carotid body tumor. Owing to enlargement of the cystic mass, the patient was referred to our center for surgery. We were unable to confirm if the lesion was a schwannoma or a branchial cyst. Therefore, we performed intracapsular resection of the tumor. The patient’s postoperative course was uneventful, with no evidence of neurodegenerative symptoms.

Background

Cases of deep neck abscess occurred secondary to pharyngolaryngitis caused by COVID-19 have been reported. Herein, we report a case of descending mediastinitis complicating COVID-19, accompanied by thyroid crisis, in which we suspected latent Graves’ disease.

Case

A 57-year-old woman was transported to our emergency room with the chief complaints of sore throat and chest pain after she had received a diagnosis of COVID-19. A chest CT showed formation of a deep neck abscess extending from around the right tonsil to the right lobe of the thyroid gland. The patient was admitted to the ICU following oral intubation and started on antibiotic therapy. On day 3 after admission, incisional drainage was performed owing to the abscess extending to the mediastinum. Although the infection was controlled by the drainage and antibiotic therapy, the patient developed fever, tachycardia, and gastrointestinal symptoms. We suspected underlying thyroid disease and performed blood examination, which showed a decreased blood level of TSH and increased blood levels of FT3/FT4 and TRAb. Based on the symptoms and results of the blood examination, the patient was diagnosed as having latent Grave’s disease. The thyroid hormones levels returned to normal range after the start of treatment with thiamazole, potassium iodide, and hydrocortisone. Antibiotic therapy was discontinued on day 39, and the patient was discharged from our hospital on day 88.

Conclusion

Caution is needed against the development of thyrotoxicosis in patients with infection near the thyroid gland, especially in those with thyroid disease. Also, a number of studies have suggested the association between COVID-19 infection and thyroid gland disease, so that further studies are warranted.