Identifying metastasis-initiating miRNA-target regulations of colorectal cancer from expressional changes in primary tumors.

Colorectal cancer (CRC) is prevalent with high mortality, with liver metastasis contributing as a major factor that worsens the survival of patients. The roles of miRNAs in CRC have been elucidated, subsequent to recent studies that suggest the involvement of miRNAs in cancer biology. In this study, we compare the miRNA and gene expression profiles of primary tumors between two groups of patients (with and without liver metastasis) to identify the metastasis-initiating microRNA-target gene regulations. Analysis from 33 patients with metastasis and 14 patients without metastasis revealed that 17 miRNAs and their 198 predicted target genes are differentially expressed, where the target genes showed association with cancer progression and metastasis with statistical significance. In order to evaluate the clinical implications of the findings, we classified CRC patients of independent data into two groups based on the identified miRNA-target regulations, where one group was closer to primary tumors with metastasis than the other group. The comparison of survival showed statistically significant difference, thereby implying the roles of the identified miRNA-target regulations in cancer progression and metastasis. The identification of metastasis-initiating miRNA-target regulations in this study will lead to better understanding of the roles of miRNAs in CRC progression.

Intracochlear schwannoma extending to vestibule.

Intralabyrinthine schwannomas are benign tumors arising de novo from the perineural Schwann cell sheath of the intralabyrinthine branches of the vestibulocochlear nerve. The development of magnetic resonance imaging (MRI) has significantly increased the diagnosis of these tumors. Intralabyrinthine schwannomas can be sub-classified into seven groups according to the structures of the inner ear that are affected. The management strategy for intralabyrinthine schwannoma is regular monitoring with MRI, as the tumor grows slowly. In cases where the tumor growth is documented on serial MRI or disturbing vestibular symptoms are present, surgical removal can be considered. The surgical approach varies based on tumor location and size. We report a case of intravestibulocochlear schwannoma causing vertigo that developed from an intracochlear tumor during MRI. We successfully removed the tumor via the transotic approach.

Preauricular sinus: advantage of the drainless minimal supra-auricular approach.

OBJECTIVES: We performed this study to introduce our minimal supra-auricular approach for the surgical management of a preauricular sinus (PAS) and to evaluate the advantages of this drainless technique. STUDY DESIGN: This was a retrospective study. SETTING: The study was done in a tertiary referral center. METHODS: We enrolled 94 patients (101 ears) with a PAS who underwent surgical treatment via a minimal supra-auricular approach performed by one surgeon between April 1999 and May 2010. After removing the specimen, meticulous subcutaneous suturing and no drain were used in 83 patients (89 ears) and a postoperative drain was inserted in 11 patients (12 ears). Surgical outcomes of this technique were compared between the groups with and without postoperative drain insertion. RESULTS: With a good surgical view and meticulous subcutaneous mattress sutures in our minimal supra-auricular approach for PAS excision, there was no postoperative recurrence or other serious complication. In the drain group, previous operation history was more frequent (P = .010), and the rate of preoperative infection was higher than in the drainless group (P = .018). Postoperatively, a compression dressing was required more frequently (P = .002) and for longer in the drain group (P = .001). The rate of immediate postoperative wound infection was higher in the drain group (P = .003). CONCLUSION: Our drainless minimal supra-auricular approach for the surgical removal of a PAS has advantage in terms of good surgical results of no recurrence and is more comfortable for patients because of the reduced need for a compression dressing. We suggest that this technique is effective and safe for PAS excision.