Long-Term Hormone Therapy Is Associated With Improved Survival in Women With Non‒Small Cell Lung Cancer
In women with non–small cell lung cancer, long-term hormone therapy, particularly estrogen plus progesterone, is associated with improved survival, according to the results of a retrospective study presented by Katcoff et al in the Journal of Thoracic Oncology. This finding may lead to further research to determine the relationship between exogenous hormones and lung cancer outcomes.
Although death rates due to lung cancer in men have fallen dramatically over the past 20 years, this has not been the case in women, for whom death rates have only slightly decreased. While various theories have been hypothesized for the continued higher death rates among women, particularly as related to non–small cell lung cancer, one theory that has not been widely examined is the effect of reproductive and hormonal factors.
Study Details and Results
To determine the possible effect of reproductive and hormonal factors on survival in women with non–small lung cancer, the investigators analyzed the medical records of 485 female patients. Patient records were obtained from the Metropolitan Detroit Cancer Surveillance System. Patient information that was obtained included medical history, smoking history, reproductive history, and environmental tobacco exposure. As for information on hormone therapy, the investigators noted the type of therapy (estrogen only, estrogen and progesterone combined, and progesterone only), the dosage, and the duration of therapy. The majority of women reported doses of 2.5 mg of progesterone and 0.625 mg of estrogen.
Of the total number of patients studied, approximately 77% were white and about 92% were smokers at some point in their lives. In addition, almost 50% of the women had been on hormone therapy. Of the 230 women who had a history of hormone therapy, 99 had taken estrogen only, 85 had taken combined estrogen and progesterone, and 3 had taken progesterone only. Women taking the combined therapy regimen were found to be older at menopause compared with women taking only estrogen.
Hormone Use a Key Predictive Factor for Survival
The investigators noted that administration of hormone therapy 11 years or more prior to a diagnosis of lung cancer was associated with increased survival. None of the other factors analyzed, including reproductive factors, affected survival rates.
Women who received combined estrogen and progesterone had significantly improved survival rates compared with those who received estrogen alone. As for the significance of hormone therapy regarding postmenopausal women, once again, treatment duration of 11 or more years significantly impacted survival rates. In addition, similar treatment durations were significant predictors of increased survival in women who were smokers or nonsmokers.
Clinical Implications
These findings showed that an increased duration of hormone therapy was associated with a decreased risk of death from non–small cell lung cancer in women. Thus, there appears to be a complex relationship between extended hormone therapy and lung cancer outcomes that requires further study. The current study findings are in contrast to previously published data from the widely acknowledged Women’s Health Initiative randomized controlled trial, which concluded that although estrogen alone did not have an impact on lung cancer incidence or mortality, combined estrogen/progesterone therapy actually increased the number of deaths from lung cancer.
The investigators remarked, “With few consistent results in the literature, more research examining the biological significance of long-term [hormone therapy] use on lung cancer outcomes is needed, with better characterization of tumors in terms of [estrogen receptor and progesterone receptor] expression.”
Ann G. Schwartz, PhD, MPH, of Barbara Ann Karmanos Cancer Institute, Detroit, is the corresponding author for the Journal of Thoracic Oncology article.
The study was funded in part by grants from the National Institutes of Health. The study authors reported no potential conflicts of interest.
The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.
