My friend is getting weaker with lung cancer. do most lung cancer patients die before a year?

Depends: The prognosis will depend on the stage and the type/ biology of the lung cancer. The type of treatments, the response to the treatments as well as patient's overall condition prior to the treatment started are also important factors. Depending to the above factors- patients with lung cancers can live from only a few /several months to several years or can be cured in the very early stage.

Performance: Status is a means of assessing how active, or how much time one needs to spend in chair or bed bound. Weight loss is also common. Those with poor performance, weight loss and evidence of spread are indicators or shorter survival. Tv dramas hand down time lines, using medians helps little. Only god knows survival.

Unfortunately yes: Majority of the patients with lung cancer are gone in about a year.

Lung cancer: Most patients with lung cancer esp stage 4 or advanced lung cancer carry a poor prognosis and survival is 12-15 months average with modern era chemotherapy. It can lead to progressive generalized weakness, fatigue and failure to thrive. Your friends stage and health status will determine his outcome. The role of chemotherapy is palliative;tarceva/iressa can work in nonsmokers w egfr mutations.

Depends : Cell type size location metastasis not uncommon with small cell.