Bon-Seok Koo

Central lymph node metastases in unilateral papillary thyroid microcarcinoma

The indications for and appropriate extent of prophylactic central lymph node (CLN) dissection for clinically node‐negative patients with unilateral papillary thyroid microcarcinoma (PTMC) are unknown.

Sialolithiasis in a stump of Wharton's duct of an aplastic unilateral submandibular gland

Congenital absence of the salivary glands is an uncommon disorder. Isolated aplasia of a unilateral submandibular gland is rare and only 6 cases have been reported. The formation of a sialolith within the remaining Whartons duct, associated with isolated aplasia of a unilateral submandibular gland, has not been reported previously. The authors report two cases of sialolithiasis within the ipsilateral remaining Whartons duct in patients with isolated aplasia of a unilateral submandibular gland.

Transforming growth factor β1 enhances stemness of head and neck squamous cell carcinoma cells through activation of Wnt signaling

Transforming growth factor β (TGFβ) ligands, including TGFβ1, are multifunctional cytokines known as key regulators of cell growth, differentiation and inflammation. Dysregulated TGFβ signaling is common in numerous solid tumors, including head and neck squamous cell carcinoma (HNSCC). Previously, TGFβ ligands were also reported to be associated with an enhancement of stemness in glioma stem-like cells. However, their role in HNSCC cancer stem cells (CSCs) has not been explored. The present study demonstrated that TGFβ1 enriches the properties of HNSCC CSCs. TGFβ1 promoted sphere formation and increased stemness-associated gene expression (Oct4 and Sox2) of primary HNSCC CSCs. Additionally, the population of aldehyde dehydrogenase (ALDH)-positive cells was increased subsequent to exogenous treatment of cells with TGFβ1. In addition, following stimulation with TGFβ1, the cells exhibited more resistance to cisplatin and elevated expression of Twist, Snail and Slug. Mechanistically, TGFβ1 acts as an upstream stimulator of Wnt/β-catenin signaling. Collectively, the present findings provide insights toward the development of TGFβ1 signaling inhibition strategies for treating HNSCC CSCs.

Primary pharyngeal tuberculosis presenting as a submucosal tumour

We describe a rare case of primary pharyngeal tuberculosis without pulmonary involvement in which the lesion was thought to be a submucosal tumour with overlying intact mucosa. A 58-year-old male attended the outpatient ward due to a globus sensation in the throat of 2-month duration. A swelling of the posterior oropharyngeal wall was found. The lesion was thought to be a submucosal tumour on computed tomography and magnetic resonance imaging. Primary pharyngeal tuberculosis was confirmed by histopathological examination and polymerase chain reaction (PCR) analysis. The patient underwent 26 weeks of treatment with anti-tuberculous agents. He has been followed up for 12 months without any signs of disease recurrence.

P048: HPV Infection Is an Etiologic Factor of Tonsillar Carcinoma

OBJECTIVES: Lymphomas represent the second most common type of tonsil malignancy. Ten percent of lymphomas occur in the head and neck, of which 40% arise in the tonsils. The contralateral tonsil may harbor occult disease, as evidenced by this study. METHODS: A 49-year-old male presented with two months of right-sided odynophagia caused by an ulcer along the medial aspect of the right tonsil. He lacked constitutional and leftsided symptoms. A neck CT demonstrated parapharyngeal soft-tissue fullness and confirmed a palpable 1.3 cm jugulodigastric node. Chest CT revealed mediastinal nodes measuring up to 1.5 cm and a 2.8 x 1.6 cm epigastric mass. PET scan showed metabolic FDG-activity in the right parapharyngeal region (16.0), right cervical lymph node (3.2), mediastinum (3.0), and at the epigastric site (20.6). The left tonsil had no activity. Biopsies, including a contralateral tonsillectomy, were planned, implementing a lymphoma protocol. RESULTS: The right tonsil biopsy revealed a “malignant neoplasm with extensive necrosis.” Additional tissue was requested, warranting a tonsillectomy. A large cell lymphoma was identified. The right tonsil cytology was consistent with a follicular lymphoma that had transformed to a large B-cell lymphoma. Regional biopsies, demonstrating squamous mucosa with underlying “reactive” and “atypical” lymphoid infiltration, were negative for malignancy. Unexpectedly, the clinically normal left tonsil contained a follicular lymphoma. Adjuvant chemoradiotherapy is planned to treat this patient with Stage III disease. CONCLUSIONS: A contralateral tonsillectomy is justified during the staging of malignant neoplasms, even in the absence of clinical or radiologic findings, as the result may reveal occult disease.