Exogenous estrogen is associated with growth of hepatocellular adenomas (HCAs), although the influence of progestin-only agents is unknown. We therefore evaluated the association of progestin-only agents on HCA progression compared to no hormone exposure and compared to estrogen exposure in female patients.
In this single-center, retrospective cohort study of reproductive-aged female patients (ages 16-45) with diagnosed HCAs between 2003 and 2021, we evaluated radiographic HCA growth during discrete periods of well-defined exogenous hormone exposures.
A total of 34 patients were included. Nineteen (55.9%) had follow-up scans during periods without hormone exposure, 7 (20.6%) during estrogen exposure, and 8 (23.5%) during progestin-only exposure. Over a median follow-up of 11 months, percent change in sum of adenoma diameters from baseline to last available scan was -15.0% with progestin-only agents versus 29.4% with estrogen exposure (p = 0.04), and -7.4% with no hormonal exposure (p = 0.52 compared to progestin-only). Greater than 10% growth was observed in two individuals (25.0%) with progestin-only agent use (one patient on high-dose progestin for menorrhagia) versus five individuals (71.4%) with estrogen use (p = 0.13), and 7 (36.8%) with no exogenous hormone use (p = 0.68 vs progestin-only).
During discrete periods of progestin-only use, HCA growth overall declined, similar to declining growth during periods without exogenous hormonal exposure. This differed from discrete periods of exogenous estrogen exposure, during which time HCAs demonstrated overall increased growth. Though larger studies are needed, these findings support recent guidance supporting progestin-only agents for female patients with HCAs seeking non-estrogen alternatives for contraception.
In this small retrospective study, we observed overall decrease in HCA size during discrete periods of progestin-only contraception use, similar to that observed during periods without exogenous hormone exposure, supporting their use as a safe alternative to estrogen-containing contraceptives in this patient population.

BACKGROUND. The classification of hepatocellular adenomas (HCAs) was updated in 2017 on the basis of genetic and molecular analysis. OBJECTIVE. The purpose of this article was to evaluate features on gadoxetate disodium-enhanced MRI of HCA subtypes on the basis of the 2017 classification and to propose a diagnostic algorithm for determining subtype using these features. METHODS. This retrospective study included 56 patients (49 women, seven men; mean age, 37 ± 13 [SD] years) with histologically confirmed HCA evaluated by gadoxetate disodium-enhanced MRI from January 2010 to January 2021. Subtypes were reclassified using 2017 criteria: hepatocyte nuclear factor-1α mutated HCA (HHCA), inflammatory HCA (IHCA), β-catenin exon 3 activated HCA (β-HCA), mixed inflammatory and β-HCA (β-IHCA), sonic hedgehog HCA (shHCA), and unclassified HCA (UHCA). Qualitative MRI features were assessed. Liver-to-lesion contrast enhancement ratios (LLCERs) were measured. Subtypes were compared, and a diagnostic algorithm was proposed. RESULTS. The analysis included 65 HCAs: 16 HHCAs, 31 IHCAs, six β-HCA, four β-IHCA, five shHCA, and three UHCAs. HHCAs showed homogeneous diffuse intralesional steatosis in 94%, whereas all other HCAs showed this finding in 0% (p < .001). IHCAs showed the \"atoll\" sign in 58%, whereas all other HCAs showed this finding in 12% (p < .001). IHCAs showed moderate T2 hyperintensity in 52%, whereas all other HCAs showed this finding in 12% (p < .001). The β-HCAs and β-IHCAs occurred in men in 63%, whereas all other HCAs occurred in men in 4% (p < .001). The β-HCAs and β-IHCAs had a mean size of 10.1 ± 6.8 cm, whereas all other HCAs had a mean size of 5.1 ± 2.9 cm (p = .03). The β-HCAs and β-IHCAs showed fluid components in 60%, whereas all other HCAs showed this finding in 5% (p < .001). Hepatobiliary phase iso- or hyperintensity was observed in 80% of β-HCAs and β-IHCAs versus 5% of all other HCAs (p < .001). Hepatobiliary phase LLCER was positive in nine HCAs (eight β-HCAs and β-IHCAs; one IHCA). The shHCA and UHCA did not show distinguishing features. The proposed diagnostic algorithm had accuracy of 98% for HHCAs, 83% for IHCAs, and 95% for β-HCAs or β-IHCAs. CONCLUSION. Findings on gadoxetate disodium-enhanced MRI, including hepatobiliary phase characteristics, were associated with HCA subtypes using the 2017 classification. CLINICAL IMPACT. The algorithm identified common HCA subtypes with high accuracy, including those with β-catenin exon 3 mutations.

Liver adenomatosis (LA) is characterized by the presence of at least 10 hepatocellular adenomas (HCAs), but the natural history of this rare liver disorder remains unclear. Thus, we aimed to reappraise the natural history and the risk of complications in a cohort of patients with at least 10 HCAs.
We analyzed the natural history of 40 patients with LA, excluding glycogen storage disorders, in a monocentric cohort. Pathological examination was performed, with immunostaining and molecular biology carried out on surgical specimens or liver biopsies.
Forty patients (36 female) were included with a median follow-up of 10.6 (1.9-26.1) years. Six (15%) patients had familial LA, all with germline HNF1A mutations. Median age at diagnosis was 39 (9-55) years. Thirty-three (94%) women had a history of oral contraception, and 29 (81%) women had a pregnancy before LA diagnosis. Overall, thirty-seven (93%) patients underwent surgery at diagnosis. Classification of HCAs showed 46% of patients with HNF1A-mutated HCA, 31% with inflammatory HCA, 3% with sonic hedgehog HCA, 8% with unclassified HCA. Only 15% of the patients demonstrated a \"mixed LA\" with different HCA subtypes. Hepatic complications were identified in 7 patients: 1 patient (3%) died from recurrent hepatocellular carcinoma after liver transplantation; 6 (15%) had hemorrhages, of which 5 occurred at diagnosis, with 1 fatal case during pregnancy, and 2 occurred in male patients with familial LA. Four patients (10%) had repeated liver resections. Finally, 4 (10%) patients developed extrahepatic malignancies during follow-up.
The diversity in HCA subtypes, as well as the occurrence of bleeding and malignant transformation during long-term follow-up, underline the heterogeneous nature of LA, justifying close and specific management. In patients with germline HNF1A mutation, familial LA occurred equally frequently in males and females, with a higher rate of bleeding in male patients.
Liver adenomatosis is a rare disease characterized by the presence of 10 or more hepatocellular adenomas that may rarely be of genetic origin. Patients with liver adenomatosis have multiple adenomas of different subtypes, with a risk of bleeding and malignant transformation that justify a specific management and follow-up.

Hepatocellular adenomas (HCA) are rare, hormone-driven, benign liver tumours. HCA >50 mm are associated with haemorrhage and malignant transformation. Guidelines recommend cessation of oral contraceptive pills (OCP) for size reduction; however, it is currently unknown how HCA respond to cessation of OCP. We sought to investigate the effect of OCP cessation on HCA size.
A retrospective cohort study was performed including HCA patients who stopped OCP intake within 6 months of imaging between 2005 and 2018. Biometrics and hormonal medication use were evaluated with self-designed questionnaires. Response of the largest HCA was evaluated according to Response Evaluation Criteria in Solid Tumours (RECISTv1.1). Cox regression was performed for analysis of factors influencing HCA regression.
Seventy-eight HCA patients were included, diagnosed at a median (interquartile range) age of 32 (26-41) years. Follow-up was 1.6 (0.4-2.9) years. HCA size at diagnosis ranged 10-167 mm. After a median time of 1.3 (0.6-2.6) years after OCP cessation, 37.2% of HCA showed ≥30% regression, 5.1% complete regression, 56.4% stability and 1.3% progression. No HCA-induced complications were observed during follow-up. Cox regression analysis demonstrated a significant association of HCA size with rate of regression; 50 ≤ HCA < 100 mm (HR 2.4, 95% CI 1.1-5.3; P < 0.05), HCA ≥ 100 mm (HR 8.3, 95% CI 3.3-21.6; P < 0.001).
Ninety-eight per cent of HCA remained stable or regressed after OCP cessation. A longer wait-and-see period was associated with a larger proportion of regressing HCA, without HCA-related complications during follow-up.

BACKGROUND: Mesenteric angiography is a sensitive method for visualizing portal perfusion in the dog.
OBJECTIVE: To evaluate hepatic portal perfusion in dogs with incompletely resectable hepatic tumors using mesenteric angiography.
METHODS: Five client-owned dogs with incompletely resectable hepatic tumors evaluated with mesenteric angiography.
METHODS: Retrospective case series. Electronic medical records at the Animal Medical Center were analyzed to identify dogs that underwent mesenteric portography to determine blood flow to nonresectable hepatic tumors and subsequently determine ideal routes for transarterial embolization, vascular stent placement, or both. The images obtained from mesenteric angiography were analyzed and compared to those obtained from computed tomography angiography.
RESULTS: Portography was accomplished using direct mesenteric venography in 3 dogs with hepatocellular carcinoma (HCC), cranial mesenteric arteriography in 1 dog with hepatic adenoma or well-differentiated HCC, and via splenic arteriovenous fistula in 1 dog with diffuse hepatic hemangiosarcoma metastases. Mean pixel densities in areas of hepatic tumor growth identified statistically significant decreases in portal blood flow (P = .02) compared to normal hepatic parenchyma.
CONCLUSIONS: Initial findings indicate that the blood supply to large and metastatic hepatic tumors in dogs may correlate with that in humans, such that the majority of the tumor blood supply arises from the hepatic artery and not the portal vein. Differences in blood supply between normal hepatic parenchyma and hepatic tumors might be exploited by developing selective tumor therapies such as arterial embolization or chemoembolization that largely spare normal liver tissue. Further investigation is warranted.

A 24-month oral carcinogenicity study of permethrin was conducted by feeding male and female CD-1 mice diets containing concentrations of 0, 20, 500, and 2,000 ppm of permethrin (males) or 0, 20, 2,500, and 5,000 ppm of permethrin (females). After approximately two years on study, surviving mice were sacrificed for the evaluation of chronic toxicity and/or carcinogenicity. An expert panel of pathologists was convened as a Pathology Working Group (PWG) to review coded liver histology sections from male and female mice and to classify all liver neoplasms according to current nomenclature and diagnostic criteria guidelines. The PWG results indicate that permethrin induced a significant dose-dependent increase in the incidence of hepatocellular neoplasms in treated female mice ( p < .01) as well as a nonstatistically significant increase in the incidence of hepatocellular tumors in treated male mice. Given the continuum of the diagnoses of adenoma and carcinoma, and the difficulty in distinguishing some of the lesions, it is appropriate to consider only the combined incidences of hepatocellular tumors (adenoma and/or carcinoma) for biological significance and risk assessment.

OBJECTIVE: Steatohepatitic hepatocellular carcinoma (SH-HCC) is a newly proposed concept, which shows histological features of steatohepatitis in HCC lesions, and it is strongly associated with metabolic syndrome (MS) and steatosis/steatohepatitis in non-cancerous lesions. Recently, a substantial number of HCC associated with MS were reported to have developed from pre-existing inflammatory hepatocellular adenoma (HCA). To elucidate the characteristic features of SH-HCC, we clinicopathologically investigated strictly diagnosed SH-HCC and non-SH-HCC (standard HCC).
METHODS: This was a retrospective multicenter study. A clinicopathological investigation was undertaken to compare 62 cases with SH-HCC features to 31 age- and sex-matched standard HCC cases, including an immunohistochemical study using markers for classification of HCA and diagnosis of HCC.
RESULTS: The characteristic features of SH-HCC compared with standard HCC include a higher rate of complications of MS, more frequent non-alcoholic fatty liver disease as an underlying liver disease, and HCC development in non-cirrhotic liver. The rate of solitary tumors showed no difference between the two groups, but the median diameter of the main tumor was greater in SH-HCCs (45 mm/20 mm, P = 0.01). The HCCs were mostly moderately differentiated, and the patterns were mainly trabecular in both groups. Positive findings for serum amyloid A and C-reactive proteins, classification markers of inflammatory HCA, were significantly higher in cancerous lesions of SH-HCC cases (50%/13%, P < 0.01 and 42%/16%, respectively; P = 0.01).
CONCLUSIONS: We confirmed that SH-HCC was strongly associated with MS and NAFLD, and found that classification markers of inflammatory HCA were significantly higher in SH-HCC. Further studies are needed to elucidate the relationship between SH-CCC and HCA for understanding the carcinogenic pathways in these diseases.

Hepatocellular adenoma is a benign liver tumour that may transform to hepatocellular carcinoma (HCC). We used data from Danish nationwide healthcare registries to investigate the incidence and prognosis of hepatocellular adenoma.
We included all patients with a hospital discharge diagnosis for benign liver tumour (ICD-10: D13.4) in 1997-2012 and a liver biopsy confirming the hepatocellular adenoma diagnosis. Follow-up began 1 year after adenoma diagnosis, to minimise the possibility that the tumour was a misdiagnosed HCC. All patients were age- and gender-matched with 50 random controls from the Danish population. We followed patients and controls with respect to HCC development, adenoma resection, and death without HCC (ie, death without having been diagnosed with HCC) through 2013. HCC diagnoses were identified in the Danish Cancer Registry.
We included 67 patients with hepatocellular adenoma, and 58 (87%) were women. The overall incidence rate of histologically verified hepatocellular adenoma in the Danish general population was 0.07 (95% CI: 0.06-0.09) per 100 000 population per year. Fifteen patients had their adenoma resected before follow-up began, leaving 52 patients for follow-up. Men with biopsy-confirmed hepatocellular adenoma had a 10-year cumulative HCC risk as high as 60.0% (95% CI: 15.3%-87.0%). All men who developed HCC were older than 50 years at adenoma diagnosis. By contrast, none of the 44 women in the follow-up analysis developed HCC.
Histologically verified hepatocellular adenoma is rare in Denmark. It is a minor concern for women, but men have a very high risk of progression to HCC.

Patients with hepatocellular adenomas are, in selected cases, candidates for liver resection, which can be approached via laparoscopy or laparotomy. The present study aimed to investigate the effects of the surgical approach on the postoperative morbidities of both minor and major liver resections.
In this multi-institutional study, all patients who underwent open or laparoscopic hepatectomies for hepatocellular adenomas between 1989 and 2013 in 27 European centers were retrospectively reviewed. A multiple imputation model was constructed to manage missing variables. Comparisons of both the overall rate and the types of complications between open and laparoscopic hepatectomy were performed after propensity score adjustment (via the standardized mortality ratio weighting method) on the factors that influenced the choice of the surgical approach.
The laparoscopic approach was selected in 208 (38%) of the 533 included patients. There were 194 (93%) women. The median age was 38.9 years. After the application of multiple imputation, 208 patients who underwent laparoscopic operations were compared with 216 patients who underwent laparotomic operations. After adjustment, there were 20 (9.6%) major liver resections in the laparoscopy group and 17 (7.9%) in the open group. The conversion rate was 6.3%. The two surgical approaches exhibited similar postoperative morbidity rates and severities. Laparoscopic resection was associated with significantly less blood loss (93 vs. 196 ml, p < 0.001), a less frequent need for pedicle clamping (21 vs. 40%, p = 0.002), a reduced need for transfusion (8 vs. 24 red blood cells units, p < 0.001), and a shorter hospital stay (5 vs. 7 days, p < 0.001). The mortality was nil.
Laparoscopy can achieve short-term outcomes similar to those of open surgery for hepatocellular adenomas and has the additional benefits of a reduced blood loss, need for transfusion, and a shorter hospital stay.

Furan is a chemical hepatocarcinogen in mice and rats. Its previously postulated cancer mode of action (MOA) is chronic cytotoxicity followed by sustained regenerative proliferation; however, its molecular basis is unknown. To this end, we conducted toxicogenomic analysis of B3C6F1 mouse livers following three week exposures to non-carcinogenic (0, 1, 2mg/kgbw) or carcinogenic (4 and 8mg/kgbw) doses of furan. We saw enrichment for pathways responsible for cytotoxicity: stress-activated protein kinase (SAPK) and death receptor (DR5 and TNF-alpha) signaling, and proliferation: extracellular signal-regulated kinases (ERKs) and TNF-alpha. We also noted the involvement of NF-kappaB and c-Jun in response to furan, which are genes that are known to be required for liver regeneration. Furan metabolism by CYP2E1 produces cis-2-butene-1,4-dial (BDA), which is required for ensuing cytotoxicity and oxidative stress. NRF2 is a master regulator of gene expression during oxidative stress and we suggest that chronic NFR2 activity and chronic inflammation may represent critical transition events between the adaptive (regeneration) and adverse (cancer) outcomes. Another objective of this study was to demonstrate the applicability of toxicogenomics data in quantitative risk assessment. We modeled benchmark doses for our transcriptional data and previously published cancer data, and observed consistency between the two. Margin of exposure values for both transcriptional and cancer endpoints were also similar. In conclusion, using furan as a case study we have demonstrated the value of toxicogenomics data in elucidating dose-dependent MOA transitions and in quantitative risk assessment.