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 [].
BH: In a 35-year-old female, a hypoechoic lesion 35 mm × 15 mm in size with a cystic appearance was detected during the US due to the presence of a palpable mass in the left neck. During the US, it was noted that the cyst had no septa inside, its wall was thin, and the lesion of the cyst was almost completely full. Cytologic findings: squamous epithelial cells were observed between sporadic inflamed cells on a dirty cystic background. It was noted that some squamous cells had dyskaryotic structures with pyknotic nuclei while reactive atypia was observed in a few cells []. Cytologic diagnosis: Branchial cyst.\nTHM: the cytopathologist noted that the lesion was cystic, and 10 cc of clear yellow fluid was obtained from the aspiration, during which the lesion shrank, which suggested that it could be a thin-wall cystic lesion. Cytodifferential diagnosis: Salivary gland lesion (e.g., Warthin tumor), cystic hygroma, cystic thyroid lesions, purulent inflammation (apsis) and metastasis of cystic squamous cell carcinoma (larynx, head/neck associated). In addition, squamous cell carcinoma cases associated with branchial cysts were defined in the literature.[]