Metastatic tumors in the oral region: a retrospective chart review of clinical characteristics and prognosis.

OBJECTIVE: The study aimed to evaluate the clinical characteristics and outcomes of patients with metastatic tumors in the oral region. STUDY DESIGN: We conducted a retrospective study of 14 patients (11 men and 3 women; median age, 70.5 years) with metastatic tumors in the oral region diagnosed between 2005 and 2018. RESULTS: The primary tumors were located in the lung (n = 7), kidney (n = 3), renal pelvis (n = 1), thyroid (n = 1), stomach (n = 1), and bladder (n = 1). The most common histologic type of the tumor was adenocarcinoma (n = 6). The metastatic sites were the mandible (n = 7), tongue (n = 4), upper gingiva (n = 2), and maxilla (n = 1). In 6 patients, metastatic tumors were found in the oral region before the primary tumors were detected. The primary tumors were detected by positron emission tomography/computed tomography in 5 patients and by computed tomography alone in one patient. Seven patients received treatment for metastatic tumors in the oral region. The overall 1- and 5-year survival rates were 35.7% and 10.7%, respectively. CONCLUSIONS: It is important to detect metastatic tumors in the oral region and primary tumors as early as possible. Radical or palliative treatment should be performed if possible, considering the condition of the primary tumor and its metastasis to other organs.

Fluctuation in radioresponse of HeLa cells during the cell cycle evaluated based on micronucleus frequency.

In this study, we examined the fluctuation in radioresponse of HeLa cells during the cell cycle. For this purpose, we used HeLa cells expressing two types of fluorescent ubiquitination-based cell cycle indicators (Fucci), HeLa-Fucci (CA)2 and HeLa-Fucci (SA), and combined this approach with the micronucleus (MN) assay to assess radioresponse. The Fucci system distinguishes cell cycle phases based on the colour of fluorescence and cell morphology under live conditions. Time-lapse imaging allowed us to further identify sub-positions within the G1 and S phases at the time of irradiation by two independent means, and to quantitate the number of MNs by following each cell through M phase until the next G1 phase. Notably, we found that radioresponse was low in late G1 phase, but rapidly increased in early S phase. It then decreased until late S phase and increased in G2 phase. For the first time, we demonstrated the unique fluctuation of radioresponse by the MN assay during the cell cycle in HeLa cells. We discuss the difference between previous clonogenic experiments using M phase-synchronised cell populations and ours, as well as the clinical implications of the present findings.