Your Thyroid Problem And Breast Cancer Risks

The links between thyroid problems and cancer have been known about for some time. As a gland linked to the immune system, the thyroid is often affected when other parts of the body are under attack. The most recent research explores the specific links between thyroid problems and breast cancer in a systematic way, bringing out ways in which the two diseases could be connected. Findings show that breast cancer sufferers have a higher than average degree of thyroid problems, and doctors should be made aware of these symptoms of thyroid problems. Moreover, it could be possible to extrapolate from the findings a causal link between thyroid problems and cancer. However, this has yet to be determined.

Or is iodine the link?

The coincidence of thyroid disease and breast cancer has long been a subject of debate. Although associations with symptoms of thyroid problems including hyperthyroidism, hypothyroidism, and goitres with the cancer have been reported in the literature, no convincing evidence exists of a causal role for thyroid disease in breast cancer. Variations in the incidence of breast cancer have been attributed to differences in dietary iodine intake so it could be that iodine rather than the thyroid itself is the missing link between the two diseases. Posssible interactions between thyroid gland and breast tissue are based on the common properties of both the mammary and thyroid cell to concentrate and transport iodine as well as on the presence of TSH receptors in fatty tissue, which is abundant in the breast.

High numbers of goitres in breast cancer patients

The present study found a high prevalance of goiter as well as a high prevalence of autoimmune thyroiditis, in breast cancer patients. An association of autoimmune thyroid disease with breast cancer has been borne out in the literature surrounding the two diseases. In those studies, increased serum levels of thyroid antibodies were identified. Although a recent study has found the levels of thyroid antibodies in British women to be lower than those in Japanese women, they found no differences between incidences in breast cancer among women of either race. However, with the use of specific immuno-tests for particular antibodies, an increased level of some of these antibodies has been demonstrated in breast cancer.

Thyroid hormones and breast cancer recovery

Knowing about these links can inform symptoms of thyroid problem and breast cancer treatment positively. Recently, it has been proposed that the presence of thyroid abnormalities may influence breast cancer progression. That is, there may be a better prognosis for breast cancer among patients with increased levels of thyroid hormones. It has been proposed that the immune response might be directed both by tumour and by thyroid tissue or that the tumour and thyroid tissue share common properties, as they both express TPO and the sodium iodide symporter gene. Although high TPO level has been shown to be a very important factor in antibody-dependent cell cytotoxicity in the thyroid, and there may be a possible association between autoimmune thyroiditis and the immune system, there is no agreement on the significance of its association with breast cancer.


The hormonal system is as yet not fully understood. All possible links between symptoms of thyroid problems and cancers like breast cancer need to be investigated time and time again so that eventually we will have a clear picture of what we can and cannot control in the treatment of hormonal and glandular diseases such as thyroid problems and breast cancer.

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