The present study was undertaken to compare positive rate of immunostaining (PR) and positive intensity of immunostaining (PI) of epidermal growth factor receptor (EGFR) in inverted papilloma (IP), synchronous carcinoma with IP and metachronous carcinoma with IP of the nasal cavity. Ten subjects with nasal polyps, ten subjects with inverted papilloma (IP), five subjects with synchronous carcinoma with IP and ten subjects with metachronous carcinoma with IP were enrolled with a control group of ten subjects of inferior turbinate. Each specimen was divided into two portions: one for RNA isolation and the other for detection of EGFR protein. Positive rate of immunostaining, positive intensity of immunostaining for EGFR protein and EGFR mRNA were significantly up-regulated in the IP, synchronous carcinoma with IP and metachronous carcinoma with IP when comparing polyp and normal mucosa. A role for EGFR in the malignant transformation from IP to SCC of the nasal cavity is suggested.

Ear piercing (EP) is increasing in popularity among teenagers. Techniques for EP should be selected carefully to prevent possible complications. The purpose of this study is to compare the clinical outcomes of EP techniques between CO(2) laser and spring-loaded gun. This is a prospective and comparative clinical trial. Under local anesthesia, EP was performed on left ear with CO(2) laser (20 watt/single mode) and on right ear with spring-loaded gun. With visual analog scale (VAS, 0-10) and questionnaire, post-operative pain and wound healing status were assessed immediately, 1, 2, 4 and 8 weeks after EP procedure. Fourteen subjects (14/17, 82.4%) completed the whole study. Immediately after the procedure, the level of post-operative pain (VAS) was 3.2 for CO(2) laser and 1.5 for spring-loaded gun (p < 0.05). In CO(2) laser group, pain severity decreased to 0.4, 0.1, 0, and 0, while in spring-loaded gun group, the decrease was only to 0.7, 0.6, 0.3 and 0 at 1, 2, 4, and 8 weeks, respectively. Duration of post-operative pain was 3.8 and 17.5 days for CO(2) laser and spring-loaded gun, respectively (p < 0.05). There was no major complication like infection, bleeding or hypertrophic scar. Our study suggests that CO(2) laser is a precise, simple, safe and aseptic technique for EP. It has a lower level and shorter duration of post-operative pain, when compared with spring-loaded gun. Therefore, CO(2) assisted EP is an alternative and feasible technique in our daily clinical practice. The level of evidence: 2b.