Focal adenoma

Hepatic lesions (adenomas, focal nodular hyperplasia, hepatocellular carcinoma, etc) Rarely, benign and malignant hepatic adenomas have been associated with the use of hormonal contraceptives. Severe abdominal pain, shock, or death may be due to rupture and hemorrhage of a liver tumor. 

B artolozzi C, Lencioni R, Paolicchi A, et al. Differentiation of hepatocellular adenoma and focal nodular hyperplasia of the liver comparison of power Doppler imaging and conventional color Doppler sonography. EurRadiol 1997 7 1410-1415. 

Oral contraceptives, estrogens, and benign liver tumors The effects of oral contraceptives on the liver include not only benign liver tumors (focal nodular hyperplasia, hepatic adenoma, and hemangioma) (74) and hepatocellular carcinoma, but also peliosis hepatis (75), sinusoid dilatation (76), and such probably unrelated shorter-term complications as jaundice and gallstones. 

Marks WH, Thompson N, Appleman H. Failure of hepatic adenomas (HCA) to regress after discontinuance of oral contraceptives. An association with focal nodular hyperplasia (FNH) and uterine leiomyoma. Ann Surg 1988 208(2) 190-5. 

Benign liver tumors (hepatocellular adenoma and focal nodular hyperplasia) are extremely rare conditions that appear to be related to oral contraceptive use (212). 

Elypoechoic lesions - adenomas, focal fat accumulation, FNEl, lymphadenopathy, etc. 132... 

The following lesions may be hypoechoic (7.) metas-tases, (2.) liver cell carcinoma, (3.) adenomas, (4.) focal nodular hyperplasia, (5.) abscesses, (6.) haematomas, (7.) early liver infarction, (S.) foci showing reduced fatty infiltration, (9.) lymphomas, and (10.) lipomas. In individual cases, differentiation between a benign and a malignant structural defect may cause considerable difficulties. (59) (s. fig. 9.4)... 

In 80-90% of cases, focal nodular hyperplasia shows a typical, radial (spoke-like) arrangement of coiled vessels in the area of the tumour, which originate from a circular artery. Occasionally, fine a.v. shunts are present. The smooth-edged lesion is hypervascular. The parenchymal phase, with its homogeneous concentration of contrast medium, allows the lesion to be clearly demarcated from healthy liver tissue. (156) Hepatic adenoma is generally hypervascular. Displaced vessels are frequently visible. 

Hepatic adenomas and focal nodular hyperplasia dynamic CT study Radiology 1986 160 53-58... 

Hepatic adenoma consists of atypical, strand-like hepa-tocytes. It is characterized by normal perfusion and an extensive absence of Kupffer cells as well as irregularity of the bile ducts. Scintigraphically, it is possible to demonstrate that there is no elimination of iminodiacetates from the adenoma and that uptake of the radioactive tracer is prolonged compared with the normal liver parenchyma ( trapping on IDA scans). (38) No colloidal albumin or Tc-colloid is taken up - this allows differentiation of an adenoma from focal nodular hyperplasia. The use of the SPECT technique increases sensitivity. 

In the case of differential diagnosis of adenoma versus focal nodular hyperplasia, scintigraphy is indicated, whereas in the case of metastases, more reliable imaging techniques are preferred, (s. fig. 9.4)... 

H. Technetium-99m DISIDA hepatobiliary agent in diagnosis of hepatocellular carcinoma, adenoma, and focal nodular hyperplasia. J. Nucl. Med. 1989 30 1278-1279... 

As regards the neoformation of benign tumours, distinction is made between nodular adenoma and focal nodular hyperplasia (FNH). Because there are several transitional types between these two forms, they are generally regarded as variants of the same basic type of tumour (H.-W. Altmann, 1980). Both types may be multiple, (s. tab. 29.10)... 

Focal nodular hyperplasia FNH is the most common benign hepatic neoplasia. As with adenoma, it may develop after the patient has taken oestrogens for a longer period (usually more than 4 or 5 years). In some cases, the lesion develops within 6 to 12 months after intake begins. (13, 125) en the oral contraceptives are discontinued, the tumour regresses or disappears (completely). The rate of both oestrogen-induced hepatocellular adenoma and FNH was considerably reduced after the introduction of low-dose oral contraceptives. 

Evidence that focal nodular hyperplasia tends to degenerate into malignant tumours is still lacking. Hepatocellular adenomas pose the (rare) risk of developing into hepatocellular carcinoma (M. Davis et al., 1975). Several cases have been published in recent years. (44,86,119) We can add our own observation here. (s. fig. 29.14)... 

Fig. 29.14 Liver cell adenoma after 21 years use of oestrogens, with subcapsular focal bleedings and malignant degeneration (hepatocellular carcinoma) (s. tab. 29.10)...

The tumors are positive for synaptophysin, chromogranin, and neuron-specific enolase and may express a variety of hormones (growth hormone, prolactin, TSH, ACTH, and FSH). A few are hormone negative and are designated as null-cell adenomas. Almost all are positive for CAM 5.2, either focally or diffusely, and about half are positive for AE 1/3. They are negative for cytokeratin 7, 19, and 20, as well as S-100 protein. Pituitary transcription factor-1 is selectively expressed in tumors that express growth hormone, prolactin, and TSH. No diagnostic molecular markers are currently in use for sporadic pituitary lesions. ... 

Mammosomatotroph cell adenoma 1.2 GH and PRL in same cells pit-1 focal ER positivity... 

Silent corticotroph cell adenoma (subtype 2) 1.5 ACTH (focal) P-end (p-end>ACTH)... 

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