tumors.
Functional magnetic resonance imaging (fMRI):
This test tracks the use of oxygen and blood flow in the brain as the patient performs tasks in the MRI scanner. This is usually used for brain mapping before performing a surgery on the brain.
Positron emission tomography (PET) scan:
In a PET scan, a radioactive substance is used to visualize the hypermetabolic activity of malignant cells.
Biopsy:
A small part of the tumor is taken to find out the type.
Lumbar puncture:
In this procedure, a special needle is placed in the lower vertebra to measure the pressures in the spinal cord and brain to rule out the possibility of infection and malignancy.
Blood tests and chest X-rays:
These are also done as a part of routine investigations.
Treatment
Treatment options for the brain tumor depend on their grade. Low-grade tumors (grade I and II) are not aggressive and are treated with monitoring. However, if the need arises, surgery alone can prove helpful. Repeat scans are used to monitor all tumors, but grade II tumors are watched more closely after surgery and over time to make sure there is no recurrence. Higher-grade tumors (grade III and IV) are malignant and can grow quickly. They are more difficult to remove and require additional treatments beyond surgery, such as radiation and chemotherapy. Microscopic tumor cells can remain after surgery and will eventually grow back.
Surgery remains the mainstay of treatment; however, only partial removal may be possible in cases where the tumor is inaccessible. Biopsy is considered even if the tumor cannot be excised for the histological diagnosis; this is important for prognosis and management. Recurrence is common even if the tumor is apparently completely removed. All treatments, therefore, are intended to prolong and improve life for as long as possible. Sometimes, chemotherapy or radiation is also used after surgery to kill any remaining cancer cells. A highly focused radiation therapy known as Gamma Knife Therapy can be used for deep tumors.
Research in Treatment and New Techniques
Studies are ongoing to find a new, efficient approach to treat the more aggressive cancers that cannot be treated with surgery, radiation, and chemotherapy.
Scientists at the Georgia Institute of Technology in Atlanta have developed a new drug that has only been tested on rats. In this new approach, the cancer drugs do not act on the brain tissue directly; instead, the tumor cells are guided in an artificial track to the chemotherapeutic agents. The advantage of this technique is that it spares the healthy brain tissue from the adverse effects of cancer drugs. Tumors can spread throughout the brain to areas that a surgeon is hesitant to operate on. This is where the new technique could be useful. An artificial track takes the cells to a “tumor collector” gel located outside of the brain containing an anticancer drug. The scientists have used this approach in rats. Those who were treated were found to have a 90% size reduction in the tumor after 18 days as compared to those who were not treated.
Another study proposes the use of immunotherapy for the treatment of brain cancer. Autologous dendritic cells loaded with apoptotic bodies with a high expression of multiple tumor and tumor-associated antigens derived from an allogeneic glioma cell line were used (GBM6-AD). The cell line was incubated in physiological oxygen to enhance the immunogenicity. In vivo phenotypic markers and ex vivo cytokine responses were measured. Alloresponses to this cancer vaccine were followed over time in a population of stable patients. It was concluded that the analysis of these biomarkers could be important in foreseeing the effectiveness of future vaccines. This also provides important information for further brain tumor immunotherapy trials.
Sana Asad Chaudhary
Sarah Mahmood
National University of Sciences and Technology
Ifra Fahim Ata
Dow University of Health Sciences
See Also: Cancer Stem Cells: Overview; Clinical Trials, U.S.: Solid Tumors.
Further Readings
American Brain Tumor Association. “Brain Tumor Risk Factors.” http://www.abta.org/brain-tumor-information/risk-factors (Accessed March 2014).
Johns Hopkins Comprehensive Brain Tumor Center. “Diagnosing Brain Tumors.” http://www.hopkinsmedicine.org/neurology_neurosurgery/specialty_areas/brain_tumor/diagnosis (Accessed March 2014).
Llaguno, Alcantara. National Center for Biotechnology Information. U.S. National Library of Medicine, “Stem Cells in Brain Tumor Development” (2011) http://www.ncbi.nlm.nih.gov/pubmed/21295683 (Accessed April 2014).
Olin, Michael R. BioMed Central Ltd. “Vaccination With Dendritic Cells Loaded With Allogeneic Brain Tumor Cells for Recurrent Malignant Brain Tumors Induces a CD4+IL17+ Response.” Journal for ImmunoTherapy of Cancer. http://www.immunotherapyofcancer.org/content/2/1/4 (Accessed April 2014).
Theodosopoulos, Philip. Mayfield Clinic. “Brain Tumors: An Introduction.” http://www.mayfieldclinic.com/PE-BrainTumor.htm#.U2GkV_ldXEU (Accessed April 2014).
Brazil
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Brazil
In 2005, stem cell research became a priority for the Brazilian federal government. Since then, the country has established a legal framework that allows research with human embryos and regulates clinical studies with stem cells. Despite limitations in research funding, the good infrastructure and local advantages for conducting clinical research allow Brazil to significantly contribute to the advancement of regenerative medicine.
Science in Brazil
Brazil is the largest country and the largest economy in Latin America, with a population of 193.9 million and a gross domestic product (GDP) of $2,356 billion in 2012, and the largest investment in research and development—1 percent of its GDP—in the region. In 2012, Brazil contributed to 2.7 percent of the world research papers in Web of Science, a 145 percent increase from 2003. Despite the quantitative increase in publication, the average impact factor is still low, and efforts are under way to improve the quality of Brazil’s science.
Stem Cell Research
The first scientific articles relating to stem cells in Brazil date from the early 1990s, mostly on hematopoietic stem cells and bone marrow transplant. From 2001 on, several groups started reporting work on different sources of stem cells, including murine embryonic stem cells and mesenchymal (adult) stem cells from different sources.
In 2005, stem cell research was recognized by the ministers of science and technology and of health as a strategic area for investment. From 2005 until 2014, approximately US$35 million was invested in regenerative medicine, including US$16 million used for construction of cell culture facilities for the production of clinical-grade stem