Evaluation of Bone Metastasis from Hepatocellular Carcinoma Using 18F-FDG PET/CT and 99mTc-HDP Bone Scintigraphy: Characteristics of Soft Tissue Formation

Abstract

Purpose Bone metastasis from hepatocellular carcinoma (HCC) can present with soft tissue formation, resulting in oncologic emergency. Contrast-enhanced FDG PET/CT and bone scintigraphy were compared to evaluate characteristics of bone metastases with or without soft tissue formation from HCC. Methods Of 4,151 patients with HCC, 263 patients had bone metastases. Eighty-five patients with bone metastasis from HCC underwent contrast-enhanced FDG PET/CT. Fifty-four of the enrolled subjects had recent 99m Tc-HDP bone scintigraphy available for comparison. Metastatic bone lesions were identified with visual inspection on FDG PET/CT, and maximum standardized uptake value (SUV max ) was used for the quantitative analysis. Confirmation of bone metastasis was based on histopathology, combined imaging modalities, or serial follow-up studies. Results Forty-seven patients (55%) presented with soft tissue formation, while the remaining 38 patients presented without soft tissue formation. Frequent sites of bone metastases from HCC were the spine (39%), pelvis (19%), and rib cage (14%). The soft-tissue-formation group had more frequent bone pain (77 vs. 37%, p<0.0001), higher SUV max (6.02 vs. 3.52, p<0.007), and higher incidence of photon defect in bone scintigraphy (75 vs. 0%) compared to the non-soft-tissue-formation group. FDG PET/CT had higher detection rate for bone metastasis than bone scintigraphy both in lesion-based analysis (98 vs. 53%, p=0.0015) and in patient-based analysis (100 vs. 80%, p<0 .001). Conclusions Bone metastasis from HCC showed a high incidence of soft tissue formation requiring emergency treatment. Although the characteristic findings for soft tissue formation such as photon defect in bone scintigraphy are helpful in detection, overall detectability of bone metastasis is higher in FDG PET/CT. Contrast-enhanced PET/CT will be useful in finding and delineating softtissue-forming bone metastasis from HCC.

Characteristic MRI Findings of Spinal Metastases from Various Primary Cancers: Retrospective Study of Pathologically-Confirmed Cases

“…One of these studies only contains one case of spinal metastasis which shows a large heterogeneous lobulated destructive soft-tissue invading the posterior elements and adjacent structures (15). Another study reported that 55% (47 out of 85) of HCC patients with spinal metastasis presented with soft tissue formation (17). To our knowledge, however, no study has investigated on specific enhancement pattern of metastatic tumors from HCC, making our study the first to report the possibly specific enhancement pattern.…”

“…Previous studies on spinal metastases from HCC mostly focused on clinical aspects. There have been few studies including radiologic findings of extrahepatic metastases from HCC (14)(15)(16)(17). One of these studies only contains one case of spinal metastasis which shows a large heterogeneous lobulated destructive soft-tissue invading the posterior elements and adjacent structures (15).…”

“…www.ksmrm.org JKSMRM 17(1) : [8][9][10][11][12][13][14][15][16][17][18]2013 the extraosseous soft tissue component of a neoplasm from the normal paraspinal soft tissue and neural structures (10)(11)(12). Therefore, understanding the characteristic MRI findings of spinal metastases from various primary tumors would be useful for both accurate diagnosis of spinal metastasis and identification of the origin of the primary cancer.…”

Clinical significance and predictive factors of early massive recurrence after radiofrequency ablation in patients with a single small hepatocellular carcinoma

“…Presence of hidden lesions can lead to early and/or massive recurrence after RFA, especially in patents with relatively large tumors [ 26 , 27 ]. In addition, insufficient work up for extrahepatic metastasis at the time of initial diagnosis can lead to early extrahepatic recurrence in our patients [ 28 ]. In our study, tumor located within 1 cm of the colon was another risk factor for early massive recurrence.…”

Successful Surgical Treatment of Metachronous Oligometastases from Non-B, Non-C Hepatocellular Carcinoma

“…Bone metastases is seen in 6.3% of HCC patients. The most common site of bone metastases is the spine (39%), followed by pelvis (19%) and ribs (14%) [6]. As many as 88.5% of patients with bone metastases from HCC die of liver failure resulting from intrahepatic tumor progression.…”