PT  - JOURNAL ARTICLE
AU  - Sariya Siddiqui
AU  - Christopher Florido
AU  - Martha Menchaca
AU  - Thomas Anderson
AU  - Ejaz Shamim
AU  - Nael Khayyat
TI  - Pathological outcome of unexpected or incidental focal FDG activity in the parotid gland identified on PET/CT scans, a reason for follow-up.
DP  - 2019 May 01
TA  - Journal of Nuclear Medicine
PG  - 1272--1272
VI  - 60
IP  - supplement 1
4099  - http://jnm.snmjournals.org/content/60/supplement_1/1272.short
4100  - http://jnm.snmjournals.org/content/60/supplement_1/1272.full
SO  - J Nucl Med2019 May 01; 60
AB  - 1272Objectives: The aim of this study was to evaluate the significance of focal intense activity within the parotid glands in patients who had PET scans for variable diseases including history of malignancy (excluding primary parotid cancers) as well as benign-nonmalignant diseases. Methods: We retrospectively reviewed the PET/CT scans in the last 5 years at our institution. After excluding patients with known primary parotid malignancy, a total of 113 patients were found to have focal increased metabolic activity within the parotid gland. Out of the total 113 patients, 11 patients had breast cancer, 18 lung cancer, 4 colorectal cancer, 19 head and neck cancers, 9 melanoma, 12 lymphoma, 12 renal cancer and 28 patients with variable pathologies (Sarcoidosis, Rosa Dorfman, Neurofibromatosis, Histiocytosis, unknown primary, Multiple Myeloma, CNS cancers). Results: Only patients with biopsy proven results were included in this study. Out of the 113 patients, 9 patients had tissue diagnosis through FNA, or surgical resection. Due to nature of our medical center as a tertiary medical center, many of our patients had their follow-up at their remote medical institution near their home or residence rather than our hospital. Out of the 9 patients with subsequent biopsies, 6 had metastasis from the primary tumors, one patient with Histiocytosis, one patient with Warthin’s tumor and one patient had pleomorphic adenoma. As expected, the head and neck cancers had more metastasis to the parotid gland than other cancers (33%). The renal cell cancer patient had the parotid gland as the only site for metastasis which changed the patient treatment plan. Conclusions: Focal increased FDG metabolic activity in the parotid gland require further investigation especially in the head and neck malignancy or if the results may change treatment plan as many will have unexpected metastasis.