Around 165,000 cases of lung cancer are diagnosed in the United States annually, and of these, 20 percent to 25 percent are classified as small cell lung carcinoma (SCLC). Prognosis for these patients is poor, and the disease frequently travels to the brain and central nervous system.
The probability of developing brain cancer, for example, ranges up to 80 percent. Whether or not these brain metastases directly impact mortality from the disease, however, has been unclear. Researchers studied around 430 patients with SCLC. All underwent neurological exams on a regular basis throughout their treatment for the disease to check for problems in the brain. Results showed about 18 percent of the patients already had evidence of brain cancer at the time they were diagnosed with lung cancer, although about a third were not having any symptoms related to the brain disease.
By two years later, more than half of all the patients had developed brain metastases. Patients with brain metastases had poorer survival rates than those without the distant cancer. About half of the deaths among those who developed brain cancer were directly attributed to the brain cancer.