Molecular Sequence of Events and Signaling Pathways in Cerebral Metastases

Brain metastases are the leading cause of morbidity and mortality among cancer patients, and are reported to occur in about 40% of cancer patients with metastatic disease in the United States of America. Primary tumor cells appear to detach from the parent tumor site, migrate, survive and pass through the blood brain barrier in order to establish cerebral metastases. This complex process involves distinct molecular and genetic mechanisms that mediate metastasis from these primary organs to the brain. Furthermore, an interaction between the invading cells and cerebral milieu is shown to promote this process as well. Here, we review the mechanisms by which primary cancer cells metastasize to the brain via a mechanism called epithelial-to-mesenchymal transition, as well as the involvement of certain microRNA and genetic aberrations implicated in cerebral metastases from the lung, breast, skin, kidney and colon. While the mechanisms governing the development of brain metastases remain a major hindrance in treatment, understanding and identification of the aforementioned molecular pathways may allow for improved management and discovery of novel therapeutic targets

Surgical management of cervical myelopathy: indications and techniques for multilevel cervical discectomy

Abstract BACKGROUND CONTEXT: Surgery is usually required for treatment of cervical myelopathy to decompress the neural elements, restore lordosis, and stabilize the spine. By addressing these problems, the neurological deterioration may be halted. PURPOSE: Multilevel cervical discectomy and fusion offers several advantages over other approaches. The authors describe the technique, discuss the indications, and present the potential complications associated with it. METHODS: Decompression is achieved via discectomy and subsequent removal of the osteophytes using a curetting technique. Preparation of end plates in a parallel fashion allows for gapless grafting of allograft bone for enhancement of fusion. A dynamic plate and screw system strengthens the construct. RESULTS: A high rate of fusion can be obtained using the technique of multilevel cervical discectomy and fusion with acceptable levels of complications. It is especially useful in cases of spondylosis that have a kyphotic deformity because, in addition to anterior decompression, it allows reconstruction of the spine to help restore a lordotic curvature. CONCLUSIONS: Multilevel cervical discectomy and fusion has proven to be very effective in decompressing and stabilizing the spine for treatment of cervical myelopathy.