Brief history (BH): a 43-year-old female presented with a palpable mass in the right neck. US revealed a 20 mm × 15 mm hypoechogenic lymph node (LN) in the right cervical jugular region. During US-FNA, 3 cc of hemorrhagic cystic fluid was obtained. It was believed that the cystic LN could be associated with papillary thyroid carcinoma. US was performed on the thyroid, which had not previously undergone US. The radiologist detected an 8 mm × 6 mm microcalcified nodule in the right lobe. FNA was also performed on this nodule.\nCytologic findings: (i) LN: smears from cystic fluid showed clusters of atypical thyroid follicular cells on a cystic background with hemosiderin-laden macrophages. (ii) Thyroid nodule: the hypercellular samples revealed atypical papillary clusters with occasional intranuclear vacuoles and grooves []. Cytologic diagnosis: LN: Metastasis of cystic papillary thyroid carcinoma. Right thyroid nodule: Thyroid papillary carcinoma. The cytologic diagnosis was confirmed histopathologically.\nTHMs: After the fluid was obtained from the LN during the FNA, “metastasis of thyroid papillary carcinoma,” which comes to mind first in the differential diagnosis of lesions that form cystic degenerations at the LN, was considered.[] Other lesions included in the differential diagnosis were hemangioma, metastasis from malignity in the salivary gland, squamous cell carcinoma, and malignant melanoma.[]
BH: A 50-year-old male presented with many bilateral LNs in the neck. Clinical preliminary diagnosis was lymphoma or metastasis. An assessment of the patient's file before the FNA MRI report revealed a description of a 22 mm × 18 mm asymmetrical mass lesion in the nasopharynx. Unfortunately, this information was not indicated on the FNA requisition form. US findings: the radiologist detected many conglomerated LNs in the right and left sides of the neck during the US before the FNA. An FNA was performed from the largest LNs located at the left and right supraclavicular regions, which were18 mm × 10 mm and 30 mm × 18 mm in size, respectively. Cytologic findings: malignant tumor cells were observed individually or in scattered groups on a lymphoid background and appeared reactive. Thin fusiform particles were detected inside the nucleus in some cells in malignant clusters []. Cytologic diagnosis: Undifferentiated malignant tumor. Comment: the cytologic differential included the metastasis of head/neck-associated carcinoma and Hodgkin's lymphoma due to atypical mononuclear cells in the reactive lymphoid background. Histopathology: the nasopharyngeal biopsy showed undifferentiated nasopharyngeal carcinoma.\nTHM: (1) Metastasis in the LNs in undifferentiated carcinoma of the nasopharynx involves diagnostic challenges during the FNA.[] This condition may be confused with other nonkeratinized carcinoma metastases and lymphomas (especially Hodgkin's lymphoma). (2) Bizarre cells observed in undifferentiated nasopharyngeal carcinoma may resemble atypical mononuclear cells in Hodgkin's lymphoma (Hodgkin cells) and Reed–Sternberg cells [].