Development of Histologically Verified Thyroid Diseases in Women Operated for Breast Cancer: A Review of the Literature and a Case Series

Abstract

Background: The possible relationships between breast and thyroid diseases have been reported in the literature. The purpose of our study was to evaluate the occurrence of histologically verified thyroid pathologies in women who were diagnosed with breast cancer and, after mastectomy/quadrantectomy complemented by oncological treatment, were thyroidectomized based on their periodic thyroid evaluation. Patients and Methods: Our series consist of 31 women with a mean age of 62.9 ± 10.9 years (range, 45–81) treated for breast cancer (18 right-sided, 11 left-sided, and 2 bilateral), of whom 29 were thyroidectomized, since two women who developed Graves’ disease refused thyroidectomy. These 31 women belong to a cohort of 889 women who referred to the Breast Surgery Unit of our university hospital during the period January 2010 through December 2020. Results: The mean time interval between breast cancer and thyroid pathologies was 48.1 ± 23.4 months (range, 12–95). The final diagnosis at histopathology was infiltrating ductal breast carcinoma in 26 women (with 2/26 patients having bilateral carcinoma) and infiltrating lobular breast carcinoma in the other 5 women. Ten of the twenty-nine thyroidectomized women (34.5%) had a thyroid malignancy on histology: five papillary carcinomas, three papillary micro-carcinomas and two follicular carcinomas. Two of the five women with papillary carcinoma also had histological evidence of chronic lymphocytic thyroiditis/Hashimoto’s thyroiditis, which was also detected in another five women with benign thyroid diseases. Conclusions: We suggest that breast cancer survivors should be made aware of the possible increased risk of thyroid pathologies (including thyroid malignancy) so that they can undergo screening and follow-up.

The association between fibrocystic breast and thyroid autoimmunity

“…Table 1 shown descriptive statistics of study parameters. 15 Hormonal factors may be associated with breast and thyroid diseases, as both organs are hormone-responsive and share similar hormonal pathways. For example, estrogen and progesterone receptors are present in both breast and thyroid tissues, and thyroid hormones modulate the estrogen receptors' expression in breast cancer cells.…”

“…18 Additionally, some studies have suggested that hypothyroidism might be related to breast cancer in postmenopausal women. 15 Autoimmunity and functional immune system alterations have also been proposed as predisposing factors for the association between thyroid and breast disorders. 13 Several studies have worked on the association between thyroid and breast disorders, with varying results.…”

“…14 Some studies suggest that females who suffer from hypothyroidism are more prone to develop breast cancer, but the relationship between the two conditions remains unclear. 15 Our study adds to the existing literature by investigating the association between fibrocystic breast and thyroid autoimmunity, but further research is required better to understand the association between thyroid and breast pathologies.…”

Thyroid Metastasis from Primary Breast Cancer

“…Moreover, BC and differentiated thyroid cancer (DTC) are the most common malignancies among women and endocrine cancers, respectively, and their simultaneous presentation in the same patient should raise the suspicion of synchronous primary cancers, especially in light of the shared risk factors for these two types of tumors. [ 14 , 15 , 16 ]. Rare cases of TM from BC within another primary malignant thyroid cancer (“tumor-to-tumor metastasis”) have also been reported [ 17 , 18 ].…”