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: a 30-year-old female complained of a palpable mass in the right breast. A cystic lesion was identified in the previous US. At the time of the US, the FNA radiologist noticed thickening in the wall surrounding the cyst that was 26 mm × 14 mm in size. First, the cyst was aspirated, and 3 cc of partially thick cystic fluid was obtained. Consequently, a sample in the form of “bird-pecking” was taken from the cystic wall. Cytologic diagnosis: (i) Cystic fluid: cystic macrophages were observed in a partially dirty inflamed background. (ii) Wall samples: malignant ductal epithelial groups were observed []. Histopathology: Infiltrating ductal carcinoma.\nTHM: sampling not only from the cyst but also from the wall enabled the detection of the malignancy.[]