User:Kolpinge1191/Glioblastoma

Epidemiology
About three per 100,000 people develop the disease a year, although regional frequency may be much higher. The frequency in England has doubled between 1995 and 2015.

It is the second-most common central nervous system cancer after meningioma. Glioblastomas are responsible for approximately 60% of all brain tumors that are present in adults. It occurs more commonly in males than females. Although the average age at diagnosis is 64, in 2014, the broad category of brain cancers was second only to leukemia in people in the United States under 20 years of age.

 Risk Factors 

Risk factors for glioblastoma include age, sex, race, lifestyle, and environmental factors. The age with the highest incidence rate of glioblastoma is between the ages of 55-60 years. Males present a higher risk for developing the brain tumor with a 3.97 per 100,000 person as compared to females with an incidence rate of 2.38. Caucasians possess the highest risk for developing glioblastoma, specifically European Americans who are 2.5 times more at risk than African Americans. People of Asian and American Indian descent are even less likely to develop the disease. Lifestyle is also a possible risk factor with an indication that an increased consumption in sugar and carbohydrate intake may lead to an increased risk in developing glioblastoma. Weight gain past the age of 25 has also shown to increase risk. Environmental concerns have risen due to the link between exposure to radiation and carbon tetrachloride and glioblastomas.

 Survival and Outcomes 

Glioblastoma is a terminal for most patients and a complete cure is extremely rare. The period in which people survive following diagnosis is minimal, on average patients live for approximately 14 to 15 months following their original diagnosis. There is a limited number of patients who live up to 2.5 years and less than 5% survive five years after their diagnosis. For those who are left untreated, the length of survival is typically around three months.

A study by Mayo Clinic revealed that other factors may contribute to a longer life expectancy upon a Glioblastoma diagnosis. Five-year survival is rare, but was achieved by those who were relatively young, female, and nonwhite, had generally good health, and a higher median income. Interestingly, it was also found that tumors on the left side of the brain, outside of the brainstem, and treated with radiotherapy also saw a longer prognosis.

Through the years, how physicians manage glioblastoma cases has been altered as research about the biology of the tumor has increased and therapeutic interventions have advanced. Perspectives on treatment have changed regarding surgery for glioblastoma patients. It has moved from limiting surgery to performing maximum resections of tumors when it’s safe and possible. Studies do suggest that maximal resection is associated with improved survival. Meaning, taking out as much of the tumor as possible can possibly increase the length of time a patient has to live with the disease. The maximal resection method has also been shown to improve other treatment methods like chemotherapy by making it easier for the drugs to be delivered into the tumor.

 Geographical Factors 

The incidence of gliomas is different in more developed countries than less developed countries, with more developed countries in the western world having higher incidence rates. Under-reported cases, limited access to health care, and different diagnostic practices may be some of the reasons these incidence rates differ. In the United States, the region with the highest incidence is the northeast and the lowest incidence being in the south-central region. The reasons for the regional differences could be due to differences in cancer reporting between regions, but it is not fully known and glioblastoma cases are sporadic like many other cancers.