fnh肝局灶性結(jié)節(jié)性增生ppt課件

1、肝局灶性結(jié)節(jié)性增生肝局灶性結(jié)節(jié)性增生Focal nodular hyperplasia (FNH) Outline FNH accounts for approximately 8% of all FNH accounts for approximately 8% of all primary hepatic tumor and is the second primary hepatic tumor and is the second most common benign liver tumor after most common benign liver tumor after hemang

2、ioma. hemangioma. This benign tumour occurs most This benign tumour occurs most commonly in women aged 2050 years, commonly in women aged 2050 years, but may occur in both men and women at but may occur in both men and women at any age, with multiple lesions being found any age, with multiple lesion

3、s being found in 20 per cent of cases.in 20 per cent of cases.FNH FNH Oral contraceptiveOral contraceptive口服避孕藥口服避孕藥 use is use is associated with FNH but the responsibility of associated with FNH but the responsibility of oral contraceptives in the occurrence of the oral contraceptives in the occur

4、rence of the lesion has not been demonstrated. lesion has not been demonstrated. Clinical symptomsClinical symptomsFNH is usually an incidental finding at imaging and only one-third are discovered because of clinical symptoms such as mild epigastric pain or discomfort and or palpable abdominal mass

5、.Blood liver tests are normal in half of the cases and show only increased in serum gamma-glutamyl-transpeptidase血清r-谷氨酰轉(zhuǎn)肽酶 activity in most of the remnants . well-circumscribed lobulated mass with central scar (arrow) and radiating septations. Pathological appearance Pathological appearanceFNH is d

6、efined as a nodule composed of benign-FNH is defined as a nodule composed of benign-appearing hepatocytes occurring in a liver that is appearing hepatocytes occurring in a liver that is otherwise histologically normal. otherwise histologically normal. FNH is a hyperplastic liver parenchyma FNH is a

7、hyperplastic liver parenchyma 增生性肝本增生性肝本質(zhì)質(zhì)subdivided into nodules by fibrous septa that subdivided into nodules by fibrous septa that may form stellate scarsmay form stellate scars星狀瘢痕星狀瘢痕. .The lesion is usually solitary (80%) and measures The lesion is usually solitary (80%) and measures less than

8、 5 cm in diameter . Occasionally, FNH is less than 5 cm in diameter . Occasionally, FNH is pedunculated(pedunculated(蒂蒂). ). Photomicrograph of histopathologic specimen shows regions of nodular hepatocellular proliferation separated by radiating bands and surrounding myxomatous scar (arrows).The mar

9、gin is sharp, often lobulated and no capsule is present . Hemorrhage and necrosis are rare. At microscopy, the central fibrotic zone is dense connective tissue致密結(jié)締組織 which contains numerous abnormally thickwalled arteries. Marked proliferation of biliary structures surrounded by inflammatory cells i

10、s observed within and at the periphery邊緣 of the fibrous septae. Kupffer cells are also seen within the lesion. FNH FNH classic(80%)non-classic(20%) (a) telangiectatic FNH, (b) with atypia, (c) mixed hyperplastic and adenomatous FNH DiagnosisCTNonenhanced Nonenhanced CT scans CT scans FNH is demonstr

11、ated as a focal hypodense FNH is demonstrated as a focal hypodense or isodense mass compared with normal liver. or isodense mass compared with normal liver. A central hypodense scar is depicted in only A central hypodense scar is depicted in only one-third of the cases . Calcifications within one-th

12、ird of the cases . Calcifications within the central scar are very rare and observed in the central scar are very rare and observed in only about 1% of the cases .only about 1% of the cases .contrast-enhanced CT scanarterial phasearterial phaseThe lesion enhances rapidly in most cases The lesion enh

13、ances rapidly in most cases and the lesion to liver contrast is high . and the lesion to liver contrast is high . Lesion contour is well demarcated and may Lesion contour is well demarcated and may be lobulated. At that time, the central scar is be lobulated. At that time, the central scar is hypode

14、nse and appears more evident than hypodense and appears more evident than on unenhanced CT scans .on unenhanced CT scans . portal venous phase portal venous phaselesion enhancement decreases and the lesion may lesion enhancement decreases and the lesion may be either iso or slightly hyperdense relat

15、ive to be either iso or slightly hyperdense relative to normal liver. Small-sized FNH may be barely visible, normal liver. Small-sized FNH may be barely visible, whereas large-sized FNH are visualized due to whereas large-sized FNH are visualized due to deformity in the liver contour or displacement

16、 of deformity in the liver contour or displacement of adjacent vessels or depiction of a relatively adjacent vessels or depiction of a relatively hypoattenuating central scar. hypoattenuating central scar. delayed phase delayed phase FNH are isodense relative to normal FNH are isodense relative to n

17、ormal liver and in most cases, central scars liver and in most cases, central scars appear iso or hyperattenuating . A central appear iso or hyperattenuating . A central scar is observed more often in large scar is observed more often in large lesions than in small lesions .lesions than in small les

18、ions .CTT1 WI T2WI Diagnosis DiagnosisMRIMRINonenhanced MRI scansNonenhanced MRI scans Typical FNHs are iso or hypointense on T1WI Typical FNHs are iso or hypointense on T1WI and iso or slightly hyperintense on T2WI.and iso or slightly hyperintense on T2WI. The central scar is hypointense on T1WI an

19、d The central scar is hypointense on T1WI and strongly hyperintense on T2WI.strongly hyperintense on T2WI.contrast-enhanced MRI scan dramatic enhancement in the arterial phase, dramatic enhancement in the arterial phase, followed by isointensity of the lesion during the followed by isointensity of t

20、he lesion during the portal venous phase. On delayed phase imaging, portal venous phase. On delayed phase imaging, the central scar shows high signal intensity. the central scar shows high signal intensity. Atypical formsscars are seen in more than 80% of cases . However, radio-pathologic papers hav

21、e demonstrated that some FNH may have no scar even at pathology especially FNH measuring less than 3 cm in diameter。 Rarely, scars remain hypodense or isodense on delayed scans or are hypointense on T2-weighted images. These findings may be observed up to 20% of cases . Nearly all FNHs are hypervasc

22、ular at the arterial phase of the enhancement, but lesion enhancement may vary at the portal phase or on delayed images. Both hypodensity or intensity of the mass on delayed phase, or on both portal vein and delayed phase images as well as hyperdensity-intensity of the mass on the portal vein phase or on both portal vein and d