To the editor, In a case report entitled “Cardiac metastasis of thyroid cancer” published in European Journal of General Medicine 2009; 6: 55-56, multiple cardiac masses was attributed to cardiac metastases from the anaplastic thyroid cancer. But, some questions should be answered by authors for identifying whether the cardiac masses was metastases of thyroid cancer or not. In this case report, the patient has not been operated. But it was pointed out that pathological examination showed an undifferentiated carcinoma of the thyroid gland. Fine-needle biopsy is an effective diagnostic modality but the diagnosis of anaplastic carcinoma should be surgical biopsy or at surgery (1). In other words, anaplastic carcinoma can not be diagnosed by fine-needle aspiration biopsy. The cardiac masses has been attributed the anaplastic thyroid cancer. But autopsy has not been performed for confirmation. Although it was been pointed out that initial cardiac evaluation was normal, possible other etiological factors of cardiac masses was able to be investigated. In conclusion, In conclusion, the diagnosis of anaplastic carcinoma and the nature of cardiac masses is suspicious. It should be discussed in order to explain the primary diagnosis and nature of the cardiac masses.