The effect of radioiodine therapy on blood cell count in patients with differentiated thyroid cancer.

PURPOSE: This study aimed to investigate the long-term effects of radioiodine treatment (RAI) on blood cell counts in patients with differentiated thyroid cancer (DTC) and to describe the characteristics of patients at high risk for blood cell count abnormalities. METHODS: The study included patients with DTC who underwent RAI treatment between 2007 and 2017. Patients with regular complete blood counts for at least 5 years were included, while those with diseases or treatments that could influence blood count parameters were excluded. Blood cell count abnormalities were defined according to the Common Terminology Criteria for Adverse Events version 5.0, and factors influencing these abnormalities were examined. RESULTS: A total of 225 patients were analyzed. The mean age at diagnosis was 45.8 ± 13.9 years, and 76.5% of patients were female. In the first year after RAI, leukocyte, neutrophil, and lymphocyte counts were significantly reduced compared with baseline values. The leukocyte and neutrophil counts returned to baseline values by the third year, while the decrease in lymphocytes continued until the fifth year. Blood cell count abnormalities developed in 16 patients (7.1%) within the first year after RAI. Risk factors for blood cell count abnormalities within the first year after RAI included male sex, older age, T4, N1, and M1 disease, as well as higher RAI doses. In logistic regression analysis, only RAI dose remained independently associated with blood cell count abnormalities. CONCLUSION: These results suggest an association between RAI dose and blood cell count abnormalities, characterized by mild lymphopenia, and indicate that the risk of mild lymphopenia persists over time. Careful consideration should be given when planning high-dose RAI for patients at a high risk of blood cell count abnormalities, such as males with metastatic disease and of advanced age.

Does the Association of Hashimoto's Thyroiditis with Differentiated Thyroid Cancer Really Have a Protective Role?

The study is an investigation of aggressive tumor features, prognosis, and disease-specific mortality rates of differentiated thyroid cancer (DTC) in the presence of concomitant Hashimoto's Thyroiditis (HT). The data of patients with DTC followed in our tertiary care center between 2000-2022 were analyzed. Variables such as patient age, gender, preoperative serum autoantibody levels, tumor characteristics, and treatment modalities were obtained from medical records. The diagnosis of HT was based either on the presence of a positive result in the pathological examination and/or on antibody positivity. A total of 637 patients [mean±SD age, 44.9±13.5 years; 485 women [76.1%)] were included in the analysis. The overall prevalence of coexistent HT was 22.9% (n=146). The disease-specific mortality associated with DTC was 2.9%. DTC patients with HT compared to those without; have more positive lymphovascular invasion (p<0.001), and lymph node metastases (p<0.001). According to the Kaplan-Meier curves, disease-specific survival rates among DTC patients without HT were significantly higher than patients with HT (log-rank p=0.002). The disease-specific mortality rate was 4.79% in DTC patients with HT, it was 1.43% in those without HT. Hashimoto thyroiditis was not associated with a 10-year recurrence-free survival (p=0.059). Differentiated thyroid cancers with concomitant HT are associated with some aggressive tumor features (such as lymphovascular invasion and nodal metastasis) and lower survival. In staging systems based on tumor risk factors, it may be useful to evaluate the presence of concomitant HT as a prognostic factor.

Relationship between pathological response and molecular subtypes in locally advanced breast cancer patients receiving neoadjuvant chemotherapy.

Majority of patients with breast cancer were diagnosed with locally advanced stages of the disease (54%). This study aimed to explain the pathological response received to neoadjuvant chemotherapy (NACT) according to the molecular classification of breast cancer in patients with locally advanced tumors. One hundred and one patients with locally advanced breast cancer treated with neoadjuvant chemotherapy were analyzed. Patients were classified into five molecular subtypes based on the profile of the estrogen receptor, progesterone receptor, HER2, and Ki-67. We determined associations between complete pathological response (no invasive tumor after neoadjuvant chemotherapy) and molecular subgroups. Most patients had luminal A tumors (n: 28, 27.7%). The overall rate of complete pathological response (pCR) was 34.7% (n:35). Tumors that presented with the highest rate of pCR were pure HER2-positive, at 60% (n:6; OR, 3.2; 95% CI, 0.8-12.2). According to logistic regression analysis, the factors affecting pCR were HER2 positivity and clinically positive axilla before NACT. Luminal A tumors had a significantly lower pCR rate. (7.1%,p: 0.001). Despite the low pCR rate, Luminal A tumor had the best survival rate in the subgroups (p < 0.001). However, there was no difference between EFS and OS according to pCR in any molecular subgroups. Pathological complete response is directly related to the subtypes of breast cancer. A high complete pathological response rate is observed in the pure HER2-positive group. However, EFS and OS were not statistically significant in patients with and without pCR.