Atsumu Kouketsu

Detection of human papillomavirus infection in oral squamous cell carcinoma: a cohort study of Japanese patients

OBJECTIVE Recent evidence suggests that human papillomavirus (HPV)-related head and neck squamous cell carcinoma (HNSCC) is a separate HNSCC subgroup with distinct epidemiology, histopathological characteristics, therapeutic response to chemotherapy and radiation, and clinical outcome. This study aimed to investigate the role of HPV infection in oral squamous cell carcinoma (OSCC) and the correlation between HPV infection, tumor suppressor protein p16 expression, and clinicopathological features in Japanese patients. METHODS In total, 174 OSCC specimens were examined for p16 levels by immunohistochemistry, and p16-positive OSCCs were analyzed for HPV DNA by in situ hybridization (ISH) and HPV genotypes by real-time PCR. The results were evaluated for the association with clinicopathological characteristics of OSCC patients. RESULTS Twenty-four OSCC samples were found positive for p16 expression; all of them were well-differentiated tumors. P16 immunoreactivity was significantly associated with the invasion depth and tended to correlate with sex, site in the oral cavity, stromal reaction, TNM stage, and survival. HPV DNA was detected in 13 of 24 (54%) p16-positive OSCC by real-time PCR; HPV 16, 18, and other high-risk genotypes were the most prevalent. However, ISH failed to detect HPV DNA in p16-positive OSCCs. CONCLUSION P16 immunoreactivity and HPV genotyping by real-time PCR may be useful markers of HPV infection in OSCC. However, although HPV-related OSCC showed good outcomes, HPV infection may have a minor role in oral oncogenesis in Japanese patients.

Clinical evaluations of autologous fibrin glue and polyglycolic acid sheets as oral surgical wound coverings after partial glossectomy

Polyglycolic acid (PGA) sheets and commercial fibrin glue are commonly used to cover open wound surfaces in oral surgery. Compared to commercial fibrin glue composed of pooled allogeneic blood, autologous fibrin glue is less expensive and poses lower risks of viral infection and allergic reaction. Here, we evaluated postoperative pain, scar contracture, ingestion, tongue dyskinesia, and postoperative bleeding in 24 patients who underwent partial glossectomy plus the application of a PGA sheet and an autologous fibrin glue covering (autologous group) versus 11 patients in whom a PGA sheet and commercial fibrin glue were used (allogeneic group). The evaluated clinical measures were nearly identical in both groups. Remarkable wound surface granulation was recognized in two cases in the autologous group. No complications were observed in either group, including viral infection or allergic reaction. Abnormal postoperative bleeding in the wound region was observed in one case in the allogeneic group. Coagulation and adhesion of the autologous fibrin glue were equivalent to those of conventional therapy with a PGA sheet and commercial fibrin glue. Thus, our results show that covering wounds with autologous fibrin glue and PGA sheets may help avoid the risks of viral infection and allergic reaction in partial glossectomy cases.

Clinical evaluations of complete autologous fibrin glue, produced by the CryoSeal® FS System, and polyglycolic acid sheets as wound coverings after oral surgery

The CryoSeal® FS System has been recently introduced as an automated device for the production of complete fibrin glue from autologous plasma, rather than from pool allogenic or cattle blood, to prevent viral infection and allergic reaction. We evaluated the effectiveness of complete autologous fibrin glue and polyglycolic acid (PGA) sheet wound coverings in mucosa defect oral surgery. Postoperative pain, scar contracture, ingestion, tongue dyskinesia, and postoperative bleeding were evaluated in 12 patients who underwent oral (including the tongue) mucosa excision, and received a PGA sheet and an autologous fibrin glue covering. They were compared with 12 patients who received a PGA sheet and commercial allogenic fibrin glue. All cases in the complete autologous fibrin glue group demonstrated good wound healing without complications such as local infection or incomplete cure. All evaluated clinical measures in this group were similar or superior to the commercial allogenic fibrin glue group. Coagulation and adhesion quality achieved with this method was comparable to that with a PGA sheet and commercial fibrin glue. Covering oral surgery wounds with complete autologous fibrin glue produced by an automated device was convenient, safe, and reduced the risk of viral infection and allergic reaction associated with conventional techniques.