| It is no secret that breast cancer is dependent on | | | | type of cancer. The main observation of this |
| hormones. There are studies that show that thyroid | | | | postulation is that patients with higher levels of |
| disorders are common in patients with this type of | | | | thyroid peroxidase were most likely to recover from |
| cancer as well as conflicting reports of their | | | | the cancer. Furthermore, it was hypothesized that |
| connection in literature. Although it has been linked to | | | | the immunologic responses of the patient might be |
| hyperthyroidism, hypothyroidism, thyroiditis, and | | | | directed at both the breast tumor and the thyroid |
| nontoxic goiter in the past, no existing evidence has | | | | gland or that both the tumor and thyroid gland |
| been made over the role of thyroid function in breast | | | | express the same properties such that the immune |
| carcinoma. However, recent studies show that there | | | | response against the tumor will have an effect on |
| is much more going on between the cancer of the | | | | the thyroid gland as well. However, there is no |
| breast and thyroid function indeed. | | | | consistency on the significance of thyroid peroxidase |
| A Possible Connection | | | | activity on cancer and a clear agreement between |
| The differences in dietary iodine have been known to | | | | the two has not yet been reached. |
| cause the geographical variations in the incidence of | | | | There have also been studies of the prevalence of |
| breast and a relationship between cancer of the | | | | breast carcinoma in patients with chronic thyroiditis. In |
| breast and iodine has been hypothesized by several | | | | another study conducted by Ito Maruchi, patients |
| authors. The probable interconnection between the | | | | with Hashimoto’s thyroiditis had an increased risk |
| thyroid gland and breast tissue are based on the | | | | of developing the particular cancer than other people |
| ability of the mammary and thyroid gland to | | | | without Hashimoto’s thyroiditis. |
| concentrate iodine by a membrane transport | | | | Patients were found to have higher levels of thyroid |
| mechanism. It has also been hypothesized that | | | | peroxidase antibodies, although their thyroglobulin |
| thyroid antibodies exert an effect on the breast as | | | | antibodies were hardly abnormal. Nodular goiter is also |
| well as the thyroid, hence, the incidence of these | | | | a common occurrence in patients with cancer of the |
| two occurring together. | | | | breasts. Abnormal thyroid gland characteristics were |
| Another study observed the high incidence of | | | | also observed in the patients. |
| autoimmune hypothyroidism in cases of patients with | | | | However, a definite agreement between thyroid |
| cancer of the breasts, as confirmed by antibody | | | | disorders and breast cancers is yet to be reached. |
| positivity in patients and a relationship between the | | | | Yet knowing the statistics and the odds, it would be |
| two has been reported. The patients were also | | | | well for patients with thyroid disorders to be more |
| found to have higher levels of thyroid antibodies. | | | | observant of breast changes. Self breast |
| Using specific assays for thyroid peroxidase and | | | | examinations or SBE and regular checkups are still |
| thyroglobulin antibodies, patients were observed to | | | | commendable for women aged 40 and above and |
| have higher levels of thyroid peroxidase antibodies. | | | | even younger for women with a history of cancer, |
| It has also been hypothesized that thyroid function | | | | especially of the breast, up in the family tree. |
| may have a hand in the progression of this particular | | | | |