We observed a downregulation of several thyroid related gene
We observed a downregulation of several thyroid-related genes such as DUOX1, DUOX2, TG, and TSHR. This may appear counterintuitive given that dedifferentiation typically worsens patient outcomes. However, it is noteworthy that there was no difference in the endo-iwr of SLC5A5 (sodium-iodide symporter), which plays a central role in radioactive iodine therapy and treatment outcomes. A previous study suggested that cytokine production in patients with papillary thyroid cancer and thyroiditis shifted toward Th2 immunity. Cytokine profiles may directly or indirectly influence the expression of thyroid-related genes. It is unlikely that our observation is influenced by the decreased tumor purity due to a higher density of lymphocyte infiltration. The initial TCGA analysis demonstrated that global expression levels were not strongly influenced by variations in levels of tumor stroma or lymphocyte infiltration. In a comprehensive study of purity correlated genes, only the expression of CTLA4 and CD274 in our analysis was influenced by the tumor purity level.
We acknowledge several limitations in this study. Varying degrees of lymphocyte infiltrations or overt thyroiditis resulting in the destruction of thyroid follicles is the most common cause of hypothyroidism in iodine-replete countries. Increasing evidence has confirmed the association between higher serum thyrotropin (TSH) concentrations and the likelihood of thyroid cancer. Treatment with thyroxine may reduce TSH levels and decrease the occurrence of thyroid cancer in patients with thyroiditis. In this study, the data of thyroid function was not available. Additionally, tumor-infiltrating lymphocytes need to be distinguished from “background” thyroiditis. The percentage of lymphocyte infiltration was based on the regular pathological examination, and phenotypical analysis was not performed in this study. The function of infiltrating lymphocytes may depend on context-sensitive profiling and may not be universal.
Conflict of interest
Acknowledgments This work was supported by a grant (MMH-TW-10504) from Mackay Memorial Hospital. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.
Introduction Infiltrating ductal breast cancer is the most common cancer in female patients, and the leading cancer in Tunisian women. A mucinous carcinoma is a relatively rare histological subtype of breast cancer, and accounts from 1 to 7% of all invasive breast cancers. This type of cancer typically presents with a massive production of extra cellular mucin. It is divided into 2 subtypes, the pure type and mixed type. The distinction between the 2 subtypes is based upon the quantification of cellularity. The pure type consists exclusively of tumor tissue with extracellular mucin production in over of 90% of the tumor, while the mixed form also contains an infiltrating ductal epithelial component without mucin. Pure mucinous breast cancer (PMBC) is characterized by a lower incidence of nodal involvement, favorable histological grade, and higher estrogen receptor (ER) and progesterone receptor (PR) expression. In fact, PMBC patients generally have a more favorable prognosis compared to invasive ductal carcinoma patients, with a low recurrence rate.
Patients and methods Fisher\'s exact test, and log-rank tests were used to compare patient and tumor characteristics, and P < 0.05 was considered statistically significant.
Results Our series comprised 56 women who presented with PMBC. Patient and tumor characteristics are listed in Table 1. Mammography was performed in 45 patients. Mammographic features included a well-circumscribed mass with lobulated margin in 30 patients (66,6%) and with spiculated margin in 12 patients (26,6%) (Figs. 1 and 2). Five- and 10-year overall survival (OS) rates were respectively 75.3% and 59.3% (Fig. 3), and 5- and 10-year disease-free survival (DFS) rates were 74% and 58%, respectively (Fig. 4). Five-year overall survivor rates according to AJCC stage I, II, III and IV were respectively 100%, 83%, 79% and 14.3% (Fig. 5).