Glioblastoma
Glioblastoma, also known as glioblastoma multiforme (GBM), is the most aggressive cancer that begins within the brain. Initially, signs and symptoms of glioblastoma are non-specific. They may include headaches, personality changes, nausea, and symptoms similar to those of a stroke. Worsening of symptoms often is rapid. This may progress to unconsciousness.
The cause of most cases is unclear. Uncommon risk factors include genetic disorders such as neurofibromatosis and Li–Fraumeni syndrome, and previous radiation therapy. Glioblastomas represent 15% of brain tumors. They can either start from normal brain cells or develop from an existing low-grade astrocytoma. The diagnosis typically is made by a combination of CT scan, MRI scan, and tissue biopsy.
There is no clear way to prevent the disease. Typically, treatment involves surgery, after which chemotherapy and radiation therapy are used. The medication temozolomide is used frequently as part of chemotherapy. High dose steroids may be used to help reduce swelling and decrease symptoms. It is unclear whether trying to remove all or simply most of the cancer is better.
Despite maximum treatment, the cancer usually recurs. The most common length of survival following diagnosis is 12 to 15 months, with fewer than 3% to 5% of people surviving longer than five years. Without treatment, survival is typically three months. It is the most common cancer that begins within the brain and the second most common brain tumor, after meningioma. About 3 per 100,000 people develop the disease a year. It most often begins around 64 years of age and occurs more commonly in males than females. Immunotherapy is being studied.
Common symptoms include seizure, headaches, nausea and vomiting, memory loss, changes to personality, mood or concentration, and localized neurological problems.
Merkel-cell carcinoma
Overall, the 5-year survival rate for Merkel cell carcinoma is around 60%. It varies depending on the stages of the cancer. In general, a higher cancer stage correlates with a lower survival rate. For example, National Cancer Data Base has survival rates collected from nearly 3000 MCC patients from year 1996-2000 with 5-year survival rates listed as follows:
Stage IA: 80%. Stage IB: 60%.
Stage IIA: 60%. Stage IIB: 50%. Stage IIC: 50%.
Stage IIIA: 45%. Stage IIIB: 25%.
Stage IV: 20%.
5 yr survival may be 51% among patients with localized disease, 35% for those with nodal disease, and 14% with metastases to a distant site.