Role of ^(18)F-FDG PET/CT in detection of hematogenous metastases of advanced differentiated thyroid carcinoma: a systematic review and meta-analysis

The aim of this study was to collect the evidence on the performance of 2-deoxy-2-[^(18)F]fluoro-D-glucose(^(18)F-FDG)Positron Emission Tomography/Computed Tomography(PET/CT)in terms of detection rate(DR)and diagnostic accuracy in identifying hematogenous metastases in patients with differentiated thyroid cancer and compare its performance with that of other imaging techniques.A comprehensive PubMed/MEDLINE database research was carried out to retrieve studies documenting the performance of^(18)F-FDG PET/CT in depicting hematogenous metastases in patients with differentiated thyroid cancer.Statistical analysis was performed on a per-patient and per-lesion basis.The literature search yielded 15 articles to be included in the systematic review.^(18)F-FDG PET/CT showed a pooled DR of 85.08%on a per-patient analysis and 89.70%on a per-lesion analysis.For bone lesions,a high DR(81.78%)was found for^(18)F-FDG PET/CT.For the sub-group analysis of lung lesions,pooled DR was 92.77%for^(18)F-FDG PET/CT,95.02%for CT,and 64.93%for magnetic resonance imaging(MRI).On a per-patient analysis,^(18)F-FDG PET/CT demonstrated a pooled sensitivity(SS)of 87.3%[95%confidence interval(CI):77.3%-94%]and a pooled specificity(SP)of 95.6%(95%CI:87.6-99.1).On a per-lesion analysis(328 metastases),PET/CT showed a pooled SS and SP of 86.3%(95%CI:73.5%-93.5%)and 93.4%(95%CI:71.7%-98.8%)in the detection of hematogenous metastases.The presented systematic review and meta-analysis favor the use of^(18)F-FDG PET/CT in the detection of hematogenous metastases in patients with differentiated thyroid cancer.The limited literature warrants further studies to confirm our findings.

Intussusception due to hematogenous metastasis of hepatocellular carcinoma to the small intestine:A case report

BACKGROUND The commonest sites of extrahepatic metastases from hepatocellular carcinoma(HCC)are the lungs,bones,adrenal glands,and regional lymph nodes.Hematogenous metastasis to the gastrointestinal(GI)tract is a rare condition in patients with HCC,and the prognosis is usually poor.We report,herein,an extremely rare case of a patient with intussusception due to hematogenous metastasis of HCC to the ileum and his long-term survival with multidisciplinary therapy.CASE SUMMARY The patient was a 71-year-old man with a history of chronic hepatitis B,who had undergone three surgeries for HCC.He was treated with sorafenib for peritoneal metastases of HCC.He was admitted to our hospital with chief complaints of abdominal pain and vomiting.Abdominal contrast-enhanced computed tomography imaging revealed a small intestinal tumor,presenting with intussusception and small bowel obstruction.Conservative treatment was started,but due to repeated exacerbation of symptoms,surgery was planned on the 28th d of hospitalization.Partial ileal resection without reducing the intussusception and end-to-end anastomosis was performed.On histological examination,tumor cells were not observed on the serosal surface,but intravascular invasion of tumor cells was seen.Immunohistochemistry was positive for immunohistochemical markers,and a diagnosis of hematogenous metastasis of HCC to the ileum was made.He remains alive 82 mo after the first surgery.CONCLUSION Prognosis of HCC patients with GI tract metastasis is usually poor,but in some cases,multidisciplinary therapy may prolong survival.