Endocrine Abstracts

Introduction: It has been shown that thyroid cancer has a significant correlation with cancers originated from other organs. The aim of this study was to investigate the association between synchronous primary cancers in patients with thyroid cancer.

Material and Method: A retrospective analysis of medical records of 560 thyroid cancer patients treated in the years 2007–2013 and followed up over 2–8 years, was performed. In 38 patients (6.7%), 5 male patients, 33 females (mean age 65.4±13.5 years,) of the analyzed group other primary malignant neoplasms were observed. Among these 30 patients follicular thyroid cancer was stated in 7 and papillary cancer – in 31 patients. Within the TNM system, thyroid cancer classification of these patients varied between in pT1aN0M0 and pT3mN1M1. Two female patients with pT1aN0M0 papillary cancer did not receive complementary radioiodine treatment.

Results: In 36 patients concurrently two malignant neoplasms occurred. In two female patients multiple concurrent primary neoplasms were stated: thyroid cancer with breast and ovary cancers, and thyroid cancer with kidneyand uterus cancers and pituitary adenoma. In the studied group breast cancer was the most frequent (14 patients), uterus cancer (4 patients), brain tumour (3 patients), blood malignancies and lung cancer (4 patients), kidney cancer (3), NET and melanoma (2 patients). Six patients were diagnosed first with thyroid cancer and next with breast cancer and in six patients breast cancer preceded thyroid cancer diagnosis and treatment. In two patients synchronous cancers were stated. During follow up one female patient died of NET of unknown origin with liver metastases.

Conclusions: It appears that female patients with thyroid cancer are more susceptible to breast cancer than the general population, therefore particular attention should be paid to diagnosing breast and thyroid nodules in these patients. The genetic background of concurrent malignant neoplasms requires further investigation.