Problem:

About 10% of lung cancer patients are cured of the disease, i.e., the survive 5 years after diagnosis with no evidence that the cancer has returned. Only 14% of lung cancer patients survive 5 years after diagnosis. Assume that the fraction of incurable lung cancer patients that survives a time t after diagnosis is given by exp(-kt). Find an expression for the fraction S(t) of lung cancer patients that survive a time t after being diagnosed with the disease.

Be sure to determine the values of all of the contants in your answer.

Required:

Question: What fraction of lung cancer patients survives two years with the disease?

Does anyone know how to go about this search to explain it.