Botulinum toxin, originally identified in relation to botulism, has evolved from being considered a perilous pathogen to an invaluable therapeutic agent. First utilized by Alan Scott in 1977 to treat strabismus under the commercial name, Oculinum, the toxin received Food and Drug Administration approval in 1989 and was subsequently rebranded as Botox. Its clinical applications have expanded notably, especially in the field of otolaryngology, proving effective in managing conditions such as spasmodic dysphonia, essential vocal tremor, and chronic salivary gland disorders. Moreover, botulinum toxin has shown promising results in treating persistent chronic rhinitis, objective tinnitus, and synkinesis following facial palsy, significantly improving involuntary facial movements. This paper details the diverse applications and methodologies of botulinum toxin across various ENT disorders, illustrating its growing scope and significance in medical practice.

The Korean Society of Laryngology, Phoniatrics and Logopedics created a task force to establish clinical practice guidelines for the use of botulinum toxin (BT) in otolaryngology. We selected 10 disease categories: spasmodic dysphonia, essential vocal tremor, vocal fold granuloma, bilateral vocal fold paralysis, Frey’s syndrome, sialocele, sialorrhea, cricopharyngeal dysfunction, chronic sialadenitis, and first bite syndrome. To retrieve all relevant papers, we searched the CORE databases with predefined search strategies, including Medline (PubMed), Embase, the Cochrane Library, and KoreaMed. The committee reported 13 final recommendations with detailed evidence profiles. The guidelines are primarily aimed at all clinicians applying BT to the head and neck area. In addition, the guidelines aim to promote an improved understanding of the safe and effective use of BT by policymakers and counselors, as well as in patients scheduled to receive BT injections.

Struma ovarii (SO) is a rare ovarian teratoma, which is diagnosed when thyroid tissue accounts for more than 50% of the teratoma. The majority of SO are benign, but malignant tumors have been reported in a small percentage of cases. Five percent of SO cases have been proven to be malignant and, as in the thyroid gland, papillary carcinoma is the most common histotype arising in SO. Because this tumor is rare, there are no guidelines regarding the management of this cancer. Usually, total thyroidectomy followed by radioiodine treatment is the treatment of choice in metastatic malignant struma ovarii, but therapeutic decisions should be made individually based on clinical and pathological data. We recently experienced a case of a 45-year-old woman finally confirmed as malignant struma ovarii with cervical thyroid cancer. Therefore, we present this unique case with a review of the literature.

Odontogenic keratocyst (OKC) accounts for 3-11% of all odontogenic cysts. OKC is a benign intra-osseous odontogenic tumor, but what makes this cyst special is its aggressive behavior and high recurrence rate. OKC is relatively aggressive compared to other odontogenic cysts, but its malignant transformation is considered extremely rare. Squamous cell carcinoma associated with odontogenic keratocysts have rarely been reported in the medical literature. We recently experienced a case of a 63-year-old man finally confirmed with squamous cell carcinoma of the mandible, which was initially diagnosed as a benign odontogenic keratocyst. Surgical resection was performed as definitive treatment. Therefore, we present this unique case with a review of the literature.

Pharyngocutaneous fistula is a readily encountered complication that occurs after surgery for laryngopharyngeal cancer. The development of pharyngocutaneous fistula increases hospitalization, delays postoperative adjuvant treatment, and can lead to serious complications such as wound infection and carotid artery rupture. Transoral robotic surgery (TORS) is actively being performed as a standard procedure for surgery of pharyngeal and laryngeal cancers. Many reports verified that TORS is advantageous in terms of perioperative outcomes such as decreased hospitalization and reduced rate of postoperative complications, free flap reconstruction, and tracheostomy or gastrostomy tube dependence relative to open surgery. However, careful selection of patients is mandatory and there are some critical points to consider in optimal treatment outcomes. Recently, we experienced a 47-year-old patient with tonsillar cancer who underwent lateral oropharyngectomy by TORS and radical neck dissection. Unfortunately, multiple pharyngocutaneous fistulae occurred following postoperative concurrent chemoradiotherapy (CCRT). Multiple phrayngocutaneous fistulae following TORS and postoperative CCRT have not been reported in the literature. Therefore, we report this case with a brief discussion supported by a review of the relevant literature.

Reprogramming of cellular metabolism is an important, emerging, and universal hallmark of cancer which has received considerable attention during the recent era of cancer research. Cancer cells show characteristic alterations in glucose metabolism in order to fulfill the needs of biosynthesis for tumor proliferation and growth. However, under certain circumstances such as invasion and metastasis, cancer cells are prone to metabolic stress and will require different strategies to meet the high energetic demand from cancer progression. From various metabolic rewiring mechanisms, cancer cells adopt other metabolic pathways with alternative nutrient sources. Therefore, targeting cancer metabolism holds promising but great challenge caused by the metabolic plasticity of cancer cells. This review will discuss characteristic cancer metabolism in detail with special focus on lipid metabolism which is gathering increasingly keen interest, in order to find novel therapeutic approaches to head and neck cancer. By understanding and exploiting the synthesis, oxidation, and storage of fatty acids, we could investigate potential strategies to block cancer proliferation and progression.

Parapharyngeal space (PPS) tumors are extremely rare, composing only 0.5% of all head and neck tumors. The PPS is shaped like an inverted pyramid bounded by the skull base superiorly and hyoid bone inferiorly. Recently, we experienced a 55-year-old female patient who visited the clinic with a presumed PPS tumor that had been incidentally identified by neck MRI. The patient underwent surgery for the removal of tumor by transoral approach following tonsillectomy. However, contrary to the initial expectations, no tumors were visible at the operative field and only observed were the evidence of chronic inflammatory tissues within the removed tonsil. To date, chronic follicular tonsillitis mimicking a PPS tumor has not been reported in the literature. Therefore, we report this case with a brief discussion of points to consider supported by a review of relevant literature.

Follicular thyroid carcinoma (FTC) is the second most common thyroid cancer, following papillary carcinoma. Metastasis to the orbital rim from FTC is very rare. We recently experienced a case of FTC with metastasis to the orbital rim in a 74-year-old woman, who initially presented with a huge thyroid mass and an asymptomatic solitary orbital rim lesion. The solitary orbital rim lesion was suspected to be a separate disease entity such as lymphoma from the preoperative imaging, but bone metastasis from FTC was finally confirmed after orbital rim resection and total thyroidectomy. During follow-up, the patient presented multiple bone metastasis, so the solitary orbital rim lesion was considered a clinical sign of systemic metastasis from FTC. Therefore, we present this unique case with a review of the literature.

Spontaneous cervical hematomas could lead to life-threatening complications, and aneurysms, retopharyngeal abscesses, parathyroid adenomas, laryngeal cysts, and neurogenic tumors should be distinguished as possible underlying causes. Symptoms accompanying spontaneous cervical hematoma include cervical swelling, ecchymosis, dysphagia, dyspnea and hoarseness. We recently experienced a case of spontaneous cervical hematoma in a 52-year-old woman, who initially presented with cervical swelling after severe coughing two days ago. Resultingly parathyroid adenoma was finally confirmed after mass excision. Therefore, we present this unique case with a review of the literature.