ABSTRACT
Objective To summarize the MRI characteristics of fat-containing hepatocellular carcinoma (HCC).Methods The retrospective cross-sectional study was conducted.The clinicopathological data of 18 patients with fat-containing HCC who were admitted to the Eastern Hepatobiliary Surgery Hospital of the Second Military Medical University between January 2015 and April 2016 were collected.All patients underwent MRI examination.Observation indicators:(1) imaging examination;(2) pathological features;(3) treatment and follow-up.Follow-up using outpatient imaging examination was performed to detect tumor recurrence once at 1 month postoperatively and once every 3 months postoperatively up to December 2016.Measurement data with normal distribution were represented as-x±s.Results (1) Imaging examination:plain scans of MRI:of 18 patients,lesions of 9,7 and 2 patients were respectively located in left,right and caudate lobes of liver,and lesions were round-like,with a diameter of 1.6-9.0 cm.Tumors were single,and tumor thrombosis in the hepatic vein was seen in 1 patient.T2WI on fat-suppression of 15 and 3 patients showed respectively high signals and iso-signal;MRI examination showed that out-phase signal on T1WI was variously decreased than in-phase signal,showing focal or diffuse signal decreasing;lipid phase on T1WI showed diffuse distribution in 10 patients,patchy fat-containing regions were scattered within the peritumoral zone in 7 patients,and lipid of 1 patient was located in the central area.Dynamic contrast enhancement MRI showed that fast-in and fast-out,fast-in and slow-out,and slow-in and slow-out types were detected in 16,1 and 1 patients,respectively.Sixteen patients had capsule-like enhancement in delayed phase.Diffusion weighted imaging (DWI) showed high signals in 10 patients,slightly high signals in 6 patients and iso-signal in 2 patients.Apparent diffusion coefficient (ADC) value was (1.19± 0.20)×10-3 mm2/s,including (1.37±0.20) × 10-3 mm2/s in lipid-rich type,(1.17±0.13) × 10-3 mm2/s in clear cell type and (1.11±0.17)× 10-3 mm2/s in thick beam type.Of 18 patients,2 were preoperatively misdiagnosed as hepatic angiomyolipoma and 1 as hepatic adenoma.(2) Pathological features:pathological types of 18 patients with fat-containing HCC:5 and 13 patients were respectively in lipid-rich and non-lipid-rich types (4 in clear cell type and 9 in thick beam type);steatosis tumor cells,rich and translucent cytoplasms and large vacuolated lipid droplets were seen under the microscope;steatosis tumor cells were diffused or scattered within the lesions,some of which showed plaque-like performance of different sizes.Degree of microvascular invasion:grade M0,M1 and M2 were found in 12,3 (2 in thick beam type and 1 in clear cell type) and 3 (2 in thick beam type and 1 in lipid-rich type) patients,respectively.(3) Treatment and follow-up:18 patients underwent surgery and were followed up for 6-13 months,with a median time of 8 months.During the follow-up,5 patients in lipid-rich type and 4 in clear cell type had no recurrence;among 9 patients in thick beam type,1 of 4 with microvascular invasion had no recurrence,2 and 1 of 4 with microvascular invasion had respectively recurrence at 3 months postoperatively and 4 months postoperatively,and 5 without microvascular invasion had no recurrence.The lesions of 3 patients with recurrence is single,3 patients received local minimally invasive therapy and continuous follow-up.Conclusion MRI characteristics of fat-containing HCC include that decreased out-phase signal on T1WI compared with in-phase signal,high signal on DWI,low ADC value,fast-in and fast-out enhancement and capsule-like enhancement in delayed phase.
ABSTRACT
Objective To compare the MRI manifestations and characteristics of ≤ 3 cm nonepithelial hepatic angiomyolipomas (HAML)and small hepatocellular carcinoma (SHCC),then improve the preoperative diagnostic accuracy.Methods A retrospective analysis of 20 patients ≤3 cm nonepithelial HAML and 26 cases of SHCC,confirmed by clinical pathology,with both in clinical data and MRI characteristics.Results ≤3 cm nonepithelial HAML commonly occurs in women;The enhancement patterns“wash in and wash out”in 1 1 cases,6 cases “wash in but slow out”,3 cases with delayed enhancement;Mature adipose tissue found in 5 cases, 3 cases has pseudocapsule enhancemen in delayed phase,13 cases can see central vessels;While SHCC often occurs in men,with“wash in and wash out”enhancement pattern in 23 cases,1 7 cases with pseudocapsule enhancemen in delayed phase,12 cases can see central vessels in lesions.ADC values for SHCC was significantly lower than that for ≤3 cm nonepithelial HAML,the ADC values of SHCC significantly lower than the surrounding liver parenchyma;The ADC values between ≤3 cm nonepithelial and liver parenchyma around has no significant differences.ADC values of liver parenchyma with liver cirrhosis was lower than that without cirrhosis.Conclusion The existence of mature adipose tissue,the MRI enhancement pattern and the value of ADC can help to distinguish between ≤3 cm nonepithelial HAML and SHCC,then improve the preoperative diagnostic accuracy.