Risk for second primary cancer higher in patients who smoked prior to first cancer

the Oncology Nurse Advisor take:

A significant behavior that increases the risk of developing cancer is cigarette smoking. This fact has been proven in countless studies, and a recent pooled analysis of five prospective cohort studies indicates that the cancer risk goes beyond developing a first primary cancer.

The analysis shows that patients who smoked 20 or more cigarettes a day prior to a diagnosis of lung (stage I), bladder, kidney, or head and neck cancer were at increased risk of developing a second primary smoking-associated cancer compared with patients who had never smoked and had survived the same first cancers. The researchers note the second primary cancers are not metastases of the first cancer, but distinct new malignancies.

Smokers who smoked fewer than 20 cigarettes per day and former smokers who had quit before their first cancer diagnosis also were at higher risk of developing a second cancer. This is the first study to explore the risk of second primary cancers in current smokers.

Although further research is needed to assess the association between smoking after a first cancer and second cancer risk, these results further support encouraging smoking cessation to all patients who smoke.