Katsura Hakamada

Hypermethylation of collagen α2 (I) gene (COL1A2) is an independent predictor of survival in head and neck cancer

OBJECTIVES Collagen production plays a role in the development of tumors from cancer cells. The aim of the present study is to examine the involvement of epigenetic alteration of Collagen α2 (I) (COL1A2) gene expression in cases of head and neck squamous cell carcinoma (HNSCC). METHODS COL1A2 expression was examined in a panel of cell lines using RT-PCR. The methylation status of the COL1A2 promoter was studied using bisulfate sequencing and methylation-specific PCR (MSP). RESULTS COL1A2 expression was absent in 6 of 11 (54.5%) UM-SCC cell lines, whereas three nonmalignant cell lines had stable expressions. MSP analysis showed that 46/98 (46.9%) contained methylated alleles. COL1A2 methylation was significantly correlated with tumor size (P = 0.041), lymph node status (P = 0.008), tumor stage (P = 0.011), H-cadherin methylation (P = 0.039) and disease-free survival (P = 0.005). On multivariate Cox proportional hazard regression, which included age, sex, smoking status, and alcohol exposure, both tumor stage and COL1A2 methylation remained independent prognostic factors. CONCLUSIONS This study suggests that CpG hypermethylation is a likely mechanism of COL1A2 gene inactivation, supporting the hypothesis that the COL1A2 gene may play a role in the tumorigenesis of HNSCC and may serve as an important biomarker.

Quattro Flap Tracheotomy—The impact of a novel surgical technique for young infants ☆ ☆☆

BACKGROUND Tracheotomy for pediatric patients is a surgical procedure with greater technical difficulty and higher rates of morbidity and mortality than that in adults. We report a new technique for pediatric tracheotomy that reduces the issue of granulation and recannulation after accidental decannulation. METHODS Clinical data were retrospectively reviewed for 32 pediatric patients aged 3weeks-32months who underwent Quattro Flap Tracheotomy (QFT) at our hospital. The technique for the procedure is described and illustrated in detail. We analyzed the complications of surgery and the prognosis of patients. RESULTS Twenty-seven out of 32 pediatric tracheotomy patients were aged <12months. Overall, one patient with subglottic stenosis developed granulation and required a resection. Three patients with granulation were cured using conservative treatment. Neither pneumothorax nor accidental decannulation and failure to reinsert the cannula occurred with QFT. No tracheotomy-related deaths occurred. The overall rate of postoperative complications was lower in the study group (4/32 cases, 12.5%) than in the control group (12/32 cases, 37.5%; p=0.041). CONCLUSION QFT is a new method for pediatric tracheotomy that should be performed in younger infants. If performed appropriately, QFT may reduce the incidence of complications and death in many cases that involve persistent granulation. LEVELS OF EVIDENCE IV.