Rare Case of Undifferentiated Pleomorphic Sarcoma of the Right Parotid Gland Correlatively Demonstrated by 18F Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography and Contrast-Enhanced Magnetic Resonance Imaging.

Malignant fibrous histiocytoma (MFH)/undifferentiated pleomorphic sarcoma (UPS) is an uncommon malignancy in the head-and-neck region. UPS is a malignant neoplasm of uncertain origin that arises both in soft tissue and bone. We bring forth a 65-year-old female who presented with an ulceroproliferative growth in the right upper neck. Contrast-enhanced magnetic resonance imaging and 18F-fluorodeoxyglucose positron emission tomography-computed tomography revealed a large exophytic, solid-cystic growth in the right parotid region with locoregional extension and few ipsilateral lymph nodes. Biopsy of the lesion revealed UPS, which was previously called MFH. She was considered for chemoradiotherapy. Correlative imaging helps in adequate staging of large tumors with assessment of response to chemoradiotherapy.

Rapidly Progressing Renal Cell Cancer of the Left Native Kidney in a Renal Transplant Recipient With Unusual Sites of Metastasis Demonstrated in Serial 18F-FDG PET/CT.

An end-stage renal disease patient underwent renal transplantation 18 years back and was on triple immunosuppression for acute rejection. She presented with left-sided abdominal lump and underwent ultrasound and noncontrast CT scan, which revealed an exophytic mass lesion in atrophic left kidney (16.2 × 13.1 × 14 cm). Baseline F-FDG PET/CT revealed a large avid exophytic mass (SUVmax 23, 17 × 14 × 13) in atrophic left kidney, with multiple retroperitoneal lymphadenopathies and a suspicious lung nodule. She underwent left open radical nephrectomy. Follow-up PET/CT after 1 month revealed multiple soft tissue deposits in operative bed and other unusual metastatic sites.