Can using premarin (conjugated estrogens) cause lung cancer?

Unlikely: It is unknown if Estrogens cause lung cancer but the answer is probably not. The two biggest causes of lung cancer include smoke exposure (passive or active) and radon. Premarin (conjugated estrogens) (an estrogen) is associated with heart attack, stroke, and blood clot but lung cancer is usually not considered an association with taking this drug.

No: Premarin (conjugated estrogens) use increases probability of breast cancer, but lung cancer does not have a similar "estrogen receptor" to stimulate growth. It's smoking active or passive in more than 90%. Radon is blamed epidemiologically, but there are many industrial and environmental carcinogens, and metals, nickel and cadmium, and last marijuana: tobacco companies like to blame every one; but tobacco is lethal.