Recurrence of Giant Cell Tumor of The Larynx.

Giant cell tumor of the larynx is a rare tumor. It was first reported by Wessely et al in 1940. Thirty-nine cases have been reported until now and together with the current case 2 recurrences were encountered. In this case report, our aim was to discuss conservative management because of the suspicion of recurrence. A 70-year-old male patient was admitted to our clinic with the complaint of hoarseness. A tumor measuring 1 × 1 cm located in the anterior half right vocal fold and extending to the anterior comissure was found on laryngeal endoscopy. Direct laryngoscopy and biopsy of the mass revealed giant cell tumor on histopathological examination. Tumor resection with cordectomy through laryngofissure and subsequently medialization thyroplasty were performed. Horaseness of the patient improved. On 2-year follow-up, a tumoral lesion suggesting recurrence was found on the vocal cord. Direct laryngoscopy and biopsy confirmed recurrence. Total laryngectomy was performed. This is the second case of recurrent giant cell tumor of the larynx. The therapy of choice should be selected considering the possibility of recurrence.

Preparation of a novel polymer-modified si surface for DNA immobilization.

The design of a novel polymer-modified overlayer composed of PPAPE and GPMS on a silicon wafer for immobilization of DNA molecules is described. After hydroxylation of Si(100) surfaces, GPMS molecules were self-assembled onto these surfaces. PPAPE molecules were then covalently attached to the epoxy-terminated surfaces. The incubation time and concentration of PPAPE was found to effect both layer thickness and water CA. The type of organic solvent and the pH were found to change the nature of the PPAPE-modified surface for DNA immobilization. It is concluded that PPAPE-modified surfaces show advantages for DNA immobilization by electrostatic interactions between DNA molecules and positively charged free amino groups of the PPAPE-modified surfaces at the appropriate pH values.