Statistics is the study of data collection, analysis, presentation, and interpretation. Data are the facts and figures that are gathered, analyzed, and summarized for presentation and interpretation.
The grade of astrocytoma has an impact on survival rates. Other factors also influence survival rates, including how much of the tumor can be removed through surgery.
Remember that statistics are estimates based on the outcomes of large numbers of individuals who have had a particular kind of tumor in the past, but they can’t predict what will happen in your situation. These figures might be perplexing, and they may leave you with additional questions. Because your doctor is aware of your condition, talk to him or her about how these figures may relate to you.
5-YEAR RELATIVE SURVIVAL RATE
A relative survival rate compares people who have the same type of tumor to the general population. For example, if the 5-year relative survival rate for a particular kind of brain tumor is 70%, it indicates that persons with that tumor are approximately 70% more likely to live for at least five years after being diagnosed than those who do not have that tumor.
STATISTICS OF ASTROCYTOMA
In a prospective study of a one year time period, 45 patients were histopathologically diagnosed with astrocytoma.
The highest incidence was 12/45 (26.6 percent) in the first ten years, with the lowest in the sixth decade increasing in the seventh decade.
Based on the statistics of astrocytoma it was observed that the highest incidence was of astrocytoma grade II. An equal number of cases were of Grade I (Pilocytic Astrocytoma) and astrocytoma Grade III (Anaplastic Astrocytoma). The slightest incidence was of Grade IV (Glioblastoma Multiforme).
According to grades of astrocytoma-
It is grade IV astrocytoma. Approximately half of all gliomas and 10-15% of all intracranial tumors are the most frequent adult primary brain tumors. It is responsible for 23% of all primary brain tumors.
Glioblastoma multiforme occurs most frequently in adults between the ages of 50 and 80. Peak incidence is between 45 to 65 years; overall incidence is 2 to 3 per 100,000 people; the ratio of male-to-female is 3:2; median survival is about three months if untreated, around 12 to 15 months with conventional therapy. Only 5% of patients survive longer than five years.
High-Grade Diffuse Anaplastic Astrocytoma:-
It is grade III astrocytoma. Anaplastic astrocytoma most commonly affects people between the ages of 30 and 50. It accounts for 4% of all brain tumors.
Most people diagnosed are between the ages of 35 and 55. Increased mitoses distinguish them from low-grade diffuse astrocytomas. They have a strong tendency to develop into glioblastoma multiforme (GBM). Survival ranges from 2 to 5 years.
Low-Grade Diffuse Astrocytoma:-
It is grade II astrocytoma and is usually an infiltrating tumor. It is responsible for approximately 5% of primary brain tumors. According to the five-year relative survival rate, it occurs 73% between 20-44 age group, 46% between 45-54 age group and 26% between 55-64 age group. After surgery, the average survival period is 6 to 8 years. More than 40% of people survive for more than ten years.
Juvenile Pilocytic Astrocytoma (JPA):-
It is grade II astrocytoma which is also an infiltrating tumor. This tumor is most common in children and adolescents and as per statistics of astrocytoma it accounts for 2% of all brain tumors.
Median survival for all patients:
Five years: 65% to 85%
Ten years: 25% to 50%