This disclosure relates to methods of managing cancer using bis-biguanide compounds, such as alexidine, and pharmaceutical compositions comprising the same. In certain embodiments, this disclosure relates to methods of treating lung cancer comprising administering an effective amount of a bis-biguanide compound to a subject in need thereof. In certain embodiments, this disclosure relates to methods of treating small cell lung cancer comprising administering an effective amount of a bis-biguanide compound to a subject in need thereof. In certain embodiments, the subject is diagnosed with a lung cancer. In certain embodiments, the subject is diagnosed with small cell lung cancer. In certain embodiments, the subject is a human subject.