“…Intracellular lumens are also seen (38, 121-123, 125, 126). Despite highly complex morphology and atypical cytology, most examples are devoid of invasive carcinoma, and, if present, invasion is usually limited in amount (121,124). The invasive component can be oncocytic, mucinous (colloid-like), sarcomatoid/undifferentiated, or even neuroendocrine type (38,123,125,127,128).…”