Thyroid Disease 101: Breast Cancer Risk Factors.
Dr. Guttler’s comments
- They occur together but does not mean one causes the other.
- Iodine trapping systems in both thyroid and breast tissue has been one possible link.
- Radioiodine treatment of thyroid cancer causes radioiodine uptake in breast tissue.
- External beam therapy for breast cancer may increase the risk to develop a second thyroid cancer.
- This association is of no help now in the actual cause or treatment of thyroid disease or breast cancers.
Possible association between thyroid and breast carcinoma
Liangbo Dong et al
World Journal of Surgical Oncology201816:130
Thyroid and breast cancer are two of the malignant diseases with highest incidence in females. Based on clinical experience, breast and thyroid cancer often occur metachronously or synchronously. Therefore, thyroid and breast cancer might share some common etiological factors. The relationship between these diseases has attracted substantial attention, and because these two glands are both regulated by the hypothalamic-pituitary axis, such a relationship is not surprising. A study of this relationship will be useful for obtaining a better understanding of the mechanism by which these two malignancies co-occur.
This study reviewed the progress in research on the roles of iodine intake, folate metabolism, obesity, gonadal hormones, and thyroid hormone in thyroid and breast cancer. These studies evaluating the etiological roles of these factors in linking breast and thyroid cancer might also improve our understanding and identify new therapeutic approaches, such as sodium/iodide symporter-mediated radioiodine therapy and thyroid-stimulating hormone receptor antagonists, for breast cancer. In addition, some specific treatments for each cancer, such as radiotherapy for breast cancer or radioactive iodine therapy for thyroid cancer, might be risk factors for secondary malignances, including breast and thyroid cancer.
Studies of the precise relationship between the co-occurrence of breast and thyroid cancer will certainly improve our understanding of the biological behaviors of these two malignancies and direct evidence-based clinical practice.