Thyroid disorders and mammographic density in Spanish women: Var-DDM study

Determinants of Adherence to World Cancer Research Fund/American Institute for Cancer Research Recommendations in Women with Breast Cancer

BACKGROUND/OBJECTIVES

The 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) cancer prevention recommendations benefit primary prevention and survivor outcomes. This study evaluated the adherence to these recommendations during the year prior to breast cancer diagnosis and identified related clinical and sociodemographic factors.

METHODS

A total of 915 patients with breast cancer were recruited from eight hospitals in four regions of Spain. The participants completed an epidemiologic questionnaire and a food frequency questionnaire. The compliance with the WCRF/AICR recommendations was assessed using a standardized score based on seven recommendations. Standardized prevalences and standardized prevalence ratios (SPRs) for moderate and high adherence were calculated based on participant characteristics using binary and multinomial logistic regression models.

RESULTS

The mean adherence was 3.5 points out of 7. The recommendations with the best and worst adherence were avoiding sugar-sweetened drinks (54.4% adherence) and maintaining a fiber-rich diet (4.4% consumed ≥30 g/day). The overall adherence was better in women aged ≥60 years (SPR = 1.55; 95% CI = 1.09-2.22), and worse in those with a caloric intake ≥2000 kcal/day (SPR = 0.48; 95% CI = 0.37-0.62) or ≥2 comorbidities (SPR = 0.66; 95% CI = 0.49-0.89). The adherence to maintaining a healthy weight was worse in those with ≥2 comorbidities and stage III-IV tumors. The physical activity adherence was worse in working women and those with ≥2 comorbidities. The alcohol restriction adherence was worse in smokers. Younger women, smokers and those with a low calorie intake were less adherent to the fruit/vegetable recommendation. The consumption of fiber and limited consumption of red/processed meat adherence was poor in all the subgroups. The adherence to a limited consumption of fast food and sugary drinks was worse in younger women and high-calorie-diet consumers.

CONCLUSIONS

The differences in the adherence to recommendations according to patient characteristics justify the design of personalized interventions for breast cancer patients.

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

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.

Hyperthyroidism is associated with breast cancer risk and mammographic and genetic risk predictors

BACKGROUND

Despite the biological link between thyroid hormones and breast cancer cell proliferation shown in experimental studies, little is known about the association between hyperthyroidism and breast cancer, as well as its association with the most common mammographic and genetic risk predictors for breast cancer.

METHODS

This study estimates the incidence rate ratios (IRRs) of breast cancer among women diagnosed with hyperthyroidism, compared to those who are not, using two cohorts: a Swedish national cohort of the general female population (n = 3,793,492, 2002-2011) and the Karolinska Mammography Project for Risk Prediction of Breast Cancer (KARMA, n = 69,598, 2002-2017). We used logistic regression to estimate the odds ratios (ORs) of hyperthyroidism according to the mammographic and genetic risk predictors for breast cancer.

RESULTS

An increased risk of breast cancer was observed in patients in the national cohort with hyperthyroidism (IRR = 1.23, 95% CI = 1.12-1.36), particularly for toxic nodular goiter (IRR = 1.38, 95% CI = 1.16-1.63). Hyperthyroidism was associated with higher body mass index, early age at first birth, and lower breastfeeding duration. Higher mammographic density was observed in women with toxic nodular goiter, compared to women without hyperthyroidism. Additionally, among genotyped women without breast cancer in the KARMA cohort (N = 11,991), hyperthyroidism was associated with a high polygenic risk score (PRS) for breast cancer overall (OR = 1.98, 95% CI = 1.09-3.60) and for estrogen receptor-positive specific PRS (OR = 1.90, 95% CI = 1.04-3.43).

CONCLUSION

Hyperthyroidism is associated with an increased risk of breast cancer, particularly for patients with toxic nodular goiter. The association could be explained by higher mammographic density among these women, as well as pleiotropic genetic variants determining shared hormonal/endocrine factors leading to the pathology of both diseases.