Unusual Metastatic Sites From Renal Cell Carcinoma Detected by 18F-FDG PET/CT Scan

Abstract

Here we describe 2 cases of renal cell carcinoma where we found the unusual metastatic sites from renal cell carcinoma on 18F-FDG PET/CT scans in post-radical nephrectomy status. The first case resolves the venous migration of the tumor as a malignant thrombus arising from a remnant stump of the left renal vein, passing through hemiazygos vein further into the azygos vein and finally into the superior vena cava just before entering into the right atrium. The second case demonstrated extensive skeletal muscle deposits involving the muscles of the trunk as well as upper and lower extremities.

Skeletal Muscle Metastasis From Renal Cell Carcinoma: A Case Series and Literature Review

“…Aurangabadkar and Ali. ( 56 ) reported an unusual case of extensive skeletal muscle metastases demonstrating as a focal hypermetabolic lesion.…”

18F-FDG PET/CT detects Metastatic Renal Cell Carcinoma Masquerading as Primary Breast Malignancy

“…Sites of metastases from RCC include lungs, bones, lymph nodes, liver, adrenals and brain in decreasing order of frequency [3]. Atypical sites of metastatic RCC include peritoneum, retroperitoneum, muscles, pleura, pancreas, spleen, urethra and ovaries [3][4][5][6][7]. Breast metastases from extra mammary tissue are extremely rare, with an estimated incidence of 0.5-2%, occurring in melanomas, lymphoma and leukemia [8,9].…”