Administration of cetuximab (C-mab) in combination with paclitaxel (PTX) has been used for patients with head and neck squamous cell carcinoma (SCC) clinically. In this study, we attempted to clarify the molecular mechanisms of the enhancing anticancer effect of C-mab combined with PTX on oral SCC cells in vitro. We used two oral SCC cells (HSC4, OSC19) and A431 cells. PTX alone inhibited cell growth in all cells in a concentration-dependent manner. C-mab alone inhibited the growth of A431 and OSC19 cells at low concentrations, but inhibited the growth of HSC4 cells very weakly, even at high concentrations. A combined effect of the two drugs was moderate on A431 cells, but slight on HSC4 and OSC19 cells. A low concentration of PTX enhanced the antibody-dependent cellular cytotoxicity (ADCC) induced by C-mab in all of the cells tested. PTX slightly enhanced the anticancer effect of C-mab in this ADCC model on A431 and HSC4 cells, and markedly enhanced the anticancer effect of C-mab on OSC19 cells. These results indicated that PTX potentiated the anticancer effect of C-mab through enhancing the ADCC in oral SCC cells.

Background/Aim: Odontogenic diseases are diagnosed based on clinical course, imaging, and histopathology. However, a definitive diagnosis is not always possible. Patients and Methods: We analyzed whole exons of SMO, BRAF, PTCH1 and GNAS using next-generation sequencing (NGS) in 18 patients. Results: Of the 6 patients with ameloblastoma, 2 patients had the same missense mutation in BRAF, and 1 patient with peripheral ameloblastoma had a missense mutation in PTCH1. Of the 7 patients with odontogenic keratocyst, 4 patients had a missense mutation in PTCH1, 2 patients had missense mutations in BRAF, and 1 patient had a missense mutation in SMO. The patient with odontoma had missense mutations in SMO, BRAF and PTCH1. One patient with cementosseous dysplasia had missense mutations in SMO and PTCH1. The patient with adenomatoid odontogenic tumor had missense mutations in SMO. Conclusion: Whole exome sequencing of the above genes by NGS would be useful for the differential diagnosis of odontogenic diseases.Odontogenic diseases (tumors, cysts and dysplasias) are diagnosed based on clinical course, several X-ray images, and histopathological findings, but a definitive diagnosis is not always possible (1). Odontogenic tumors derive from cells involved in tooth development, and in many cases, it is difficult 3233 This article is freely accessible online.

SummaryA retrospective cohort study was performed to investigate the effectiveness of preemptive postsurgical therapy with cetuximab for patients with a major risk of recurrence or metastasis after clinical complete resection of primary oral squamous cell carcinoma (OSCC). The study period was from 2007 to 2019 for patients treated at the Department of Oral and Maxillofacial Surgery, Dokkyo Medical University School of Medicine. OSCC patients with major risk (n = 88) in the follow-up period were divided into groups with no postsurgical treatment (NP group), with standard postsurgical treatment (SP group), and with postsurgical treatment including cetuximab (CP group), and prognosis were compared among those groups. The 5-year overall survival rate was significantly higher in patients who received postsurgical treatment with cetuximab (CP) compared to that in the other two groups ((CP vs. NP, p = 0.028; CP vs. SP, p = 0.042). Furthermore, we performed multivariate analysis to evaluate the effects of the main components of the treatment. Among CDDP, radiotherapy, and cetuximab, only cetuximab significantly contributed to improved survival by univariate analysis (crude HR:0.228, 95%CI:0.05–0.968, p = 0.045). cetuximab also showed the same tendency in multivariate analysis, although p value did not reach significant level (Adjusted HR: 0.233, 95%CI: 0.053–1.028, p = 0.054). The results suggest that the postsurgical treatment with cetuximab as a preemptive postsurgical therapy after complete surgical resection of a visible tumor is considerably effective for OSCC patients with major risk, in other words, invisible dormant metastasis.

Background: The surveillance methods oral squamous cell carcinoma (OSCC) patients may be chosen by considering the risk for recurrence, and it is important to establish appropriate methods during the period in which latent/dormant cancer cells become more apparent. To investigate the appropriate surveillance of patients with OSCC based on the individual risk for recurrence and/or metastasis, we performed a retrospective cohort study after the complete surgical resection of OSCC as the primary treatment. Methods: The study was performed in 324 patients with OSCC who had been primarily treated with surgery from 2007 to 2020 at our hospital. We investigated the period, timing, and methods (visual examination, palpation and imaging using FDG-PET/CT or CECT) for surveillance in each case that comprised postsurgical treatment. Results: Regarding the time to occurrence of postsurgical events, we found that half of cases of local recurrence, cervical lymph node metastasis, and distant metastasis occurred within 200 days, and 75% of all of these events occurred within 400 days. However, the mean time for second primary cancer was 1589 days. The postsurgical events were detected earlier by imaging examinations than they were by visual examination and palpation. Conclusions: For the surveillance of patients with OSCC after primary surgery, it is desirable to perform FDG-PET/CT within 3–6 months and at 1 year after surgery and to consider CECT as an option in between FDG-PET/CT, while continuing history and physical examinations for about 5 years based on individual risk assessment.