Amylase crystalloids is one of the several types of crystalline structures that can be seen in non-neoplastic and neoplastic salivary gland lesions. Here, a 60-year-old woman with an infraauricular mass existing for two years is presented. On ultrasound a cystic mass, 1 cm in diameter was detected in the tail of right parotid gland. Clear and mucoid fluid was obtained from the mass by fine-needle aspiration. Smears showed numerous rhomboid, rectangular or rod-shaped, non-birefringent crystalloid structures and a few acinar cell groups in a mucoid background rich in polymorphonuclear leucocytes and lymphoctes. It was reported as cystic sialadenitis with amylase crystalloids. In the four-month follow-up, there was no recurrence of the mass.

An 83-year-old man presented with abdominal pain, vomiting, and bloating. His abdominal CT revealed heterogeneous peritoneal thickening in the lower quadrants, which was more prominent in the pelvic region. 18 F-FDG PET/CT performed to locate the primary tumor showed irregular peritoneal and omental thickening with low to moderate FDG uptake. 68 Ga-FAPI (fibroblast activation protein-specific inhibitor)-04 PET/CT of the patient, whose primary tumor could not be detected using FDG, showed high radiopharmaceutical uptake in the areas of heterogeneous thickening on peritoneal and serosal surfaces. Peritoneal Tru-Cut biopsy revealed malignant tumoral infiltration indicating mesothelioma. This case showed that 68 Ga-FAPI-04 PET/CT could be a promising radiopharmaceutical in the evaluation of peritoneal mesothelioma.

A female patient diagnosed of infiltrative breast carcinoma using tru-cut biopsy underwent 18 flourine-fluorodeoxyglucose ( 18 F-FDG) positron emission tomography/computed tomography (PET/CT) for staging. The tumor was located in the superior external quadrant of the right breast, and did not exhibit pathological uptake in 18 F-FDG PET/CT. Later, gallium- 68 ( 68 Ga) fibroblast activation protein-specific inhibitor (FAPI)-04 PET/CT imaging was performed and the primary tumor showed intense radiotracer accumulation. This presumes that 68 Ga-FAPI PET/CT imaging is superior to 18 F-FDG imaging in detecting the primary tumor in breast cancer, thereby suggesting the replacement of FAPI by 18 F-FDG in breast-cancer staging in the future.

No abstract