Focal nodular hyperplasia of the liver: a sequela of tumor therapy

Superb Microvascular Imaging in Pediatric Focal Nodular Hyperplasia

OBJECTIVE

To investigate superb microvascular imaging (SMI), a novel Doppler ultrasound technique that can visualize low-velocity microvascular flow, for assessing pediatric focal nodular hyperplasia (FNH).

PATIENTS AND METHODS

Nine FNH lesions in 6 patients were enrolled. On SMI and color Doppler imaging (CDI), intralesional vascularity was assessed visually and categorized as typical spoke-wheel pattern (central vessel radiating from the center to the periphery), multifocal spoke-wheel pattern, and nonspecific pattern. We compared the vascular features of the lesions between SMI and CDI and evaluated vascular patterns according to lesion size.

RESULTS

In terms of vascularity pattern, the typical spoke-wheel pattern of FNH was noted more frequently on SMI (67%) than on CDI (11%; P < 0.05). In addition, a multifocal spoke-wheel pattern was noted in all remaining lesions (33%) on SMI. On the contrary, a nonspecific vascular pattern was detected in the majority (78%) of CDI. Regarding the lesion size and vascularity on SMI, the typical spoke-wheel pattern was seen more frequently in the small FNH group than in the large FNH group. The intralesional vascular signal was detected more frequently on SMI (100%) than on CDI (89%).

CONCLUSION

SMI is feasible in evaluating FNH in children and has a greater ability to demonstrate the spoke-wheel pattern than CDI.

Pedunculated Focal Nodular Hyperplasia: When in Doubt, Should We Cut It Out?

Focal nodular hyperplasia (FNH) is the second most common benign hepatic tumor and can rarely present as an exophytic solitary mass attached to the liver by a stalk. Most FNH cases are usually detected as incidental findings during surgery, imaging or physical examination and have a high female predominance. However, the pedunculated forms of FNH are particularly rare and commonly associated with severe complications and diagnostic challenges. Hence, our study aims to provide a comprehensive summary of the available data on the pedunculated FNH cases among adults and children. Furthermore, we will highlight the role of different therapeutic options in treating this clinical entity. The use of imaging techniques is considered a significant addition to the diagnostic toolbox. Regarding the optimal treatment strategy, the main indications for surgery were the presence of symptoms, diagnostic uncertainty and increased risk of complications, based on the current literature. Herein, we also propose a management algorithm for patients with suspected FNH lesions. Therefore, a high index of suspicion and awareness of this pathology and its life-threatening complications, as an uncommon etiology of acute abdomen, is of utmost importance in order to achieve better clinical outcomes.

Hepatocyte-specific contrast-enhanced MRI findings of focal nodular hyperplasia-like nodules in the liver following chemotherapy in pediatric cancer patients

PURPOSE

We aimed to assess the MRI findings and follow-up of multiple focal nodular hyperplasia (FNH)- like lesions in pediatric cancer patients diagnosed by imaging findings.

METHODS

We retrospectively analyzed clinical data and MRI examinations of 16 pediatric patients, who had been scanned using gadoxetate disodium (n=13) and gadobenate dimeglumine (n=3). Hepatic nodules were reviewed according to their number, size, contour, T1- and T2-weighted signal intensities, arterial, portal, delayed and hepatobiliary phase enhancement patterns. Follow-up images were evaluated for nodule size, number, and appearance.

RESULTS

All 16 patients received chemotherapy in due course. Time interval between the initial diagnosis of cancer and detection of the hepatic nodule was 2-14 years. Three patients had a single lesion, 13 patients had multiple nodules. The median size of the largest nodules was 19.5 mm (range, 8-41 mm). Among 16 patients that received hepatocyte-specific agents, FNH-like nodules appeared hyperintense in 11 and isointense in 5 on the hepatobiliary phase. During follow-up, increased number and size of the nodules were seen in 4 patients. The nodules showed growth between 6-15 mm.

CONCLUSION

Liver MRI using hepatocyte-specific agents is a significant imaging method for the diagnosis of FNH-like lesions, which can occur in a variety of diseases. Lesions can increase in size and number in pediatric patients.

Hepatic focal nodular hyperplasia after pediatric hematopoietic stem cell transplantation: The impact of hormonal replacement therapy and iron overload

BACKGROUND

The advent of techniques for the assessment of iron overload (liver T2*-MRI) has led to the awareness that focal nodular hyperplasia (FNH) represents a possible incidental finding after hematopoietic stem cell transplantation (HSCT), though its pathogenesis is still unclear.

METHODS

We performed a retrospective analysis of the liver T2*-MRI scans performed between 2013 and 2018 in a single pediatric HSCT Unit and recorded the number of patients with FNH (group A). Patients incidentally diagnosed with FNH at imaging performed for different clinical indications were included in group B.

RESULTS

Nine of 105 (8.6%) patients from group A were diagnosed with FNH. Group B included three patients. Overall, 12 patients were diagnosed 4.4 ± 3.1 years after HSCT. At univariate analysis, female gender (odds ratio [OR] 3.77, P = .03), moderate-to-severe iron overload (OR 6.97, P = .01), and hormone replacement therapy (HRT) administered for at least 6 months (OR 18.20, P = .0002) exposed patients to a higher risk of developing FNH. The detrimental effect of HRT was significant also at multivariate analysis (OR 7.93, P = .024). MRI-T2* values in affected patients were statistically lower than healthy controls (P < .001).

CONCLUSIONS

We confirm the high incidence of FNH among transplanted pediatric patients and demonstrate the potential pathogenic role of HRT and iron overload.

Treatment-related Focal Nodular Hyperplasia Mimicking Liver Metastases

A 7-year-old patient with a stage 4 neuroblastoma underwent chemotherapy, surgery, myeloablative therapy, external beam radiotherapy, and Isoretinoin treatment. A posttreatment magnetic resonance examination performed administering gadoteric acid as contrast agent showed 2 new hypervascular hepatic lesions, suspicious for metastases. A second magnetic resonance imaging performed using a liver-specific contrast medium (gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid) demonstrated that these lesions were consistent with treatment-related focal nodular hyperplasia.

Development of Focal Nodular Hyperplasia after Cyclophosphamide-Based Chemotherapy in a Patient with Breast Cancer

Focal nodular hyperplasia (FNH) is the second most common liver cell-derived benign tumor. It is postulated that chemotherapy-induced hepatic circulatory abnormalities, like sinusoidal obstruction syndrome (SOS), could lead to the development of FNH. Cyclophosphamide was also reported to induce SOS in a synergistic effect with total body irradiation. However, none of cyclophosphamide-related FNH had ever been reported before. In this case report, we present a female patient who was treated with neoadjuvant chemotherapy of cyclophosphamide (500mg/m²)-docetaxel (75mg/m²)-pharmorubicin (90mg/m²) regimen every 3 weeks for breast cancer developed FNH after 4 courses of treatment. The patient had no chronic liver disease, no history of smoking, drinking, or medication use. The chronological correlation between the chemotherapy and the appearance of the FNH suggested a cause-effect association. Therefore, this is the first case report about development of FNH after cyclophosphamide-based chemotherapy. Taking into account the frequency of breast cancer, it is instructive to recognize such observation of FNH in the context to make the differential diagnosis with hepatic metastasis.

Hepatobiliary phase liver MR imaging findings after Oxaliplatin-based chemotherapy in cancer patients

OBJECTIVE

To describe Gd-EOB-DTPA-enhanced liver MR imaging findings in colon and rectal cancer patients who received Oxaliplatin.

CONCLUSION

Spectrum of hepatobiliary phase imaging findings include diffuse heterogeneous dysfunction, macronodular and micronodular FNH-like lesions, and coexistence of periportal increased liver function with FNH-like lesions. Differentiation of these benign lesions from metastasis is crucial to avoid biopsy in patients with colorectal cancers and may allow better understanding of sinusoidal obstruction syndrome pathophysiology and regenerative response of liver.

Practical use and pitfalls of hepatocyte-specific contrast agents (HSCAs) for pediatric hepatic and biliary magnetic resonance imaging

Magnetic resonance imaging is commonly used to evaluate for hepatic and biliary pathology in the pediatric population. Recently, there has been increased use of hepatocyte-specific contrast agents (HSCAs), such as Gadoxetate disodium in children. Traditionally, HSCAs have been used to characterize focal liver lesions. However, these agents can also be used to problem solve specific hepatic or biliary diagnostic dilemmas. The purpose of this manuscript is to review the practical uses of HSCA in children with both hepatic and biliary indications, and review the corresponding imaging findings. We will highlight the diagnostic uses of HSCA in children, as well as pitfalls encountered.

The impact of hepatocyte phase imaging from infancy to young adulthood in patients with a known or suspected liver lesion

OBJECTIVE

Hepatocyte-specific contrast agents are used to help characterize liver lesions. However, there are no studies evaluating the utility of these agents in detecting or diagnosing pediatric liver lesions. The purpose of this study is to assess the impact of the hepatocyte phase of imaging on lesion detection, tumor staging and diagnostic confidence.

MATERIALS AND METHODS

All patients undergoing an MRI between September 2010 and August 2012 using gadoxetate disodium as the contrast agent were included in this study. Each exam was duplicated so that one copy contained all sequences, including the hepatocyte phase of imaging, and the other copy contained all sequences except the hepatocyte phase of imaging. One reviewer evaluated all exams in a blinded, random fashion. Data tracked included imaging diagnosis, confidence in diagnosis, number of lesions and PRETEXT grade. The imaging diagnosis was compared to histopathology, when available. Data were analyzed for the study population as well as the subset of patients diagnosed with focal nodular hyperplasia (FNH).

RESULTS

There were 112 patients (56 male; mean age: 9.25 years) included in this study. A total of 33 patients had a malignant tumor and the remainder had either a benign lesion or no lesion. The addition of the hepatocyte phase of imaging significantly improved the diagnostic confidence for all patients (P < 0.0001) as well as specifically for patients diagnosed with FNH (P = 0.003). In nearly a quarter of patients, the hepatocyte phase of imaging allowed the reviewer to detect additional lesions (P = 0.005). In the patients with a malignant tumor, the addition of the hepatocyte phase of imaging changed the PRETEXT grade in 7/30 patients although the results were not significant (P = 0.161).

CONCLUSION

The addition of the hepatocyte phase of imaging helps to improve lesion detection and increase the diagnostic confidence for all liver tumors, as well as for FNH in particular.

Focal nodular hyperplasia coexistent with hepatoblastoma in a 36-d-old infant

Focal nodular hyperplasia (FNH) is a benign hepatic tumor characterized by hepatocyte hyperplasia and a central stellate scar. The association of FNH with other hepatic lesions, such as adenomas, hemangiomas and hepatocellular carcinoma, has been previously reported, but FNH associated with another hepatic tumor is rare in infants. Here we report a case of FNH coexistent with hepatoblastoma in a 36-d-old girl. Computed tomography (CT) imaging showed an ill-delineated, inhomogeneous enhanced mass with a central star-like scar in the right lobe of the liver. The tumor showed early mild enhancement at the arterial phase (from 40HU without contrast to 52HU at the arterial phase), intense enhancement at the portal phase (87.7HU) and 98.1HU in the 3-min delay scan. A central scar in the tumor presented as low density on non-contrast CT and slightly enhanced at delayed contrast-enhanced scanning. This infant underwent surgical resection of the tumor. Histopathology demonstrated typical FNH coexistent with a focal hepatoblastoma, which showed epithelioid tumor cells separated by proliferated fibrous tissue.

Focal nodular hyperplasia of the liver in children after hematopoietic stem cell transplantation

FNH is a non-malignant neoplasia of the liver rarely described in children. A significant percentage of the pediatric cases have been reported in patients with a history of malignant disease treated with chemo-radiation therapy and in children who were given HSCT. Little is known about the pathogenesis of FNH in transplanted children, but many risk factors linked to the HSCT procedure have been hypothesized. The detection of hepatic nodules, particularly in children who underwent HSCT for a previous malignancy, always raises a diagnostic dilemma. To help the physicians in the diagnostic management of this rare entity, we have retrospectively evaluated a series of transplanted children diagnosed with FNH in our Center over the last 15 yr. In this period, we found 10 new diagnoses of FNH. The diagnostic work-up included CEUS, abdominal CT, and MRI. A liver biopsy was performed in two patients. The median FUP time after diagnosing FNH was 3.8 yr, with an abdominal US and no malignant transformation were observed. Possible risk factors and indications for the management of FNH in transplanted children are reported and discussed in a comprehensive review of the literature.

Benign hepatic nodular lesions after treatment for childhood cancer

BACKGROUND

Benign nodular hepatic regenerating lesions such as focal nodular hyperplasia (FNH) have been reported as rare complications of the antineoplastic therapy received during infancy. Little is known about the risk factors associated with the onset of these lesions and their diagnostic management.

METHODS

We have analyzed a series of benign hepatic nodular lesions occurring in children previously treated for malignant tumors in our institution in a period of 11 years. An extensive description of the imaging presentation of the lesions has been provided to facilitate the differential diagnosis, and a risk factor analysis has been conducted.

RESULTS

A total of 14 diagnoses (10 FNH and 4 hemangiomas) of benign nodular hepatic lesions have been found. Hematopoietic stem cell transplantation is the most important statistically independent risk factor associated with the development of these lesions, especially for FNH. No malignant transformation of nodules has been recorded during a median follow-up time of 4 years.

CONCLUSIONS

In our experience, FNH is the most frequent benign nodular hepatic lesions occurring after treatment for childhood cancer. Hematopoietic stem cell transplantation is the most important risk factor to be taken in account. After a secure diagnosis of these benign lesions, only a close imaging follow-up is recommended.

Incidence and etiology of new liver lesions in pediatric patients previously treated for malignancy

OBJECTIVE

The purpose of this study was to retrospectively evaluate the time course, cause, and imaging characteristics of all new liver lesions in pediatric patients with a previously treated malignancy.

MATERIALS AND METHODS

Our hospital cancer registry was used to identify patients between 1980 and 2005 who met the following criteria: solid tumor, survival > 2 years after diagnosis, no liver lesions at a posttreatment baseline, and cross-sectional imaging follow-up of > 2 years. Final dictated reports of all cross-sectional imaging examinations including the abdomen were reviewed for any mention of new liver lesions. Positive reports were followed by consensus review of the images and clinical data. Patients were divided into three groups: those with suspected or proven focal nodular hyperplasia (FNH), those with suspected or proven metastases, and those with other lesions. An exact Wilcoxon test was used to evaluate the differences between the groups.

RESULTS

Of 967 patients who met the initial inclusion criteria, 273 had adequate follow-up to be included in the study. Forty-six patients (16.8%) developed new liver lesions during the study period, and 14 of those 46 were classified into the FNH group (30.4%) and seven were classified into the metastasis group (15.2%). A significant difference was found in the median time to the development of FNH versus metastasis and other lesions (FNH, 92.9 months; metastasis, 43.2 months; other lesions, 18.5 months; p < 0.0001). A significant difference was also seen in the median length of follow-up between the groups (FNH, 115.6 months; metastasis, 57 months; other lesions, 50.8 months; p = 0.002). The imaging features of the groups also differed.

CONCLUSION

The most common liver lesion encountered in pediatric patients previously treated for malignancy was FNH, which occurred farther from the time of diagnosis and had different imaging characteristics from both metastases and other liver lesions.

Hypervascular hepatic nodules in childhood cancer survivors: clinical and imaging features

AIM

The aim was to review the clinical and imaging features of hypervascular hepatic nodule (HHN) in childhood cancer survivors.

MATERIALS AND METHODS

We retrospectively reviewed 11 pediatric patients (female:male, 7:4; age range, 4.0-12.3 years) who had HHNs detected by surveillance computed tomography (CT) after treatment of a malignant solid tumor and subsequently followed by serial imaging without evidence of recurrent malignancy. The lesions were analyzed in terms of number, size, location, CT and ultrasonographic (US) features, and changes in background liver. In addition, clinical features were investigated along with follow-up changes of HHNs by imaging monitoring.

RESULTS

Time between initial diagnosis of malignancy and HHN occurrence ranged from 3.2 to 8.5 years (median, 5.8 years). Ten patients had received high-dose chemotherapy and autologous stem cell transplantation for advanced neuroblastoma. A total of 22 nodules were detected, being multiple in six patients and measuring 0.5-3.0 cm in size. At sequential postcontrast CT, nodules demonstrated moderate to strong enhancement during the earlier phase and were isoattenuated during the later phase. On US, they appeared as hypo- or isoechoic lesions. During follow-up, 11 nodules (50%) regressed, 6 (27%) progressed, and 5 (23%) remained stable. Additional HHNs were noted in four patients during follow-up.

CONCLUSION

Childhood cancer survivors are at risk of developing HHNs, which are often multiple and small, years after completing chemotherapy. They are nonaggressive and tend to have a benign course, making conservative management reasonable.

Long-term hepatic outcomes in survivors of stage 4S and 4 neuroblastoma in infancy

BACKGROUND

Infants with stage 4 and 4S neuroblastoma (NB) have a superior prognosis to older children. However, they often require intensive therapy including abdominal radiation. We aimed to investigate the long-term hepatic outcomes in infants with stage 4S and 4 NB.

METHODS

We reviewed the charts of 38 infants diagnosed with stage 4S and 4 NB between 1984 and 2002. We included only those with available follow-up 5 years following diagnosis. We assessed hepatic imaging and function (transaminases, bilirubin, alkaline phosphatase) at all available time points from diagnosis. Abnormalities present at more than 5 years from diagnosis were considered persistent late changes.

RESULTS

We identified 15 stage 4S and 12 stage 4 patients. Twelve of 15 stage 4S patients had hepatic involvement at diagnosis, 8 of whom required abdominal radiation. Five of eight demonstrated late imaging changes. Two of four with hepatic metastases but no radiation demonstrated late imaging changes. The late imaging changes resolved over time and without intervention in 3/7 survivors. The persistent lesions included liver fibrosis (1) and focal nodular hyperplasia (FNH) (3). Five of 12 stage 4 NB patients had hepatic involvement at diagnosis; none required radiation or had late hepatic imaging changes.

CONCLUSIONS

In stage 4S NB, adverse hepatic effects are infrequent, may resolve over time, and occur with or without radiation. FNH should be considered in those with persistent late imaging changes. Adverse hepatic outcomes after liver involvement or radiation in infants with stage 4 NB rarely occur.

Characterization of pediatric liver lesions with gadoxetate disodium

Gadoxetate disodium (Gd-EOB-DTPA) is a relatively new hepatobiliary MRI contrast agent. It is increasingly used in adults to characterize hepatic masses, but there is little published describing its use in children. The purpose of this paper is to describe our pediatric MRI protocol as well as the imaging appearance of pediatric liver lesions using gadoxetate disodium. As a hepatocyte-specific MRI contrast agent, Gd-EOB-DTPA has the potential to improve characterization and provide a more specific diagnosis of pediatric liver masses.

Focal nodular hyperplasia of the liver after intensive treatment for pediatric cancer: is hematopoietic stem cell transplantation a risk factor?

Focal nodular hyperplasia (FNH) is a benign hepatic lesion very rarely described in the pediatric population. It has been reported more frequently in patients treated for pediatric cancers with chemotherapy or hematopoietic stem cell transplantation. The use of high dosage of alkylating agents, the occurrence of venous occlusive disease, graft-versus-host disease, and other variables linked to the hematopoietic stem cell transplantation procedure can represent risk factors for the development of FNH in the pediatric age. The discovery of hepatic nodules in the follow-up of patients treated for malignancies suggests recurrence of disease and raises a diagnostic dilemma. Here we describe possible risk factors, clinical and radiological findings of eight pediatric patients who developed focal nodular hyperplasia after hematopoietic stem cell transplantation. The aim of this report is to provide useful diagnostic tools to facilitate accurate diagnosis of FNH and suggest a correct management of this benign lesion during postcancer follow-up.

The clinical course in pediatric solid tumor patients with focal nodular hyperplasia of the liver

BACKGROUND

Focal nodular hyperplasia (FNH) of the liver is a rare benign lesion that may be related to the vascular and hepatic damage induced by completion of tumor therapy and a reaction to localized vascular abnormality. The aim of this study was to analyze the clinical course in pediatric solid tumor patients with FNH.

METHODS

We analyzed thirty-two patients with pediatric solid tumors who received multiagent chemotherapy (15 advanced neuroblastomas, 7 hepatoblastomas, 5 rhabdomyosarcomas, 2 nephroblastomas, 1 rhabdoid tumor of the kidney, 1 clear cell sarcoma of the kidney and 1 pancreatoblastoma). All of them had been previously treated at our hospital, and have been alive for over 3 years without recurrence.

RESULTS

FNH lesions were discovered in three (9.4%) of 32 patients, and were neuroblastoma (NB) stage 4. All 3 patients received induction chemotherapy and high-dose alkylating agents, and developed grade 3 (National Cancer Institute Common Toxicity Criteria; NCI-CTC) liver dysfunction during completion of tumor therapy without veno-occlusive disease. Two of the 3 patients received the same induction chemotherapy and high doses of alkylating agents with total body irradiation for cytoreductive agents prior to peripheral blood cell transplantation. FNH lesions in both female patients who received estrogen replacement therapy after completion of tumor therapy have expanded and are increasing.

CONCLUSION

FNH appears to be a late complication of iatrogenic disease in NB stage 4 patients. The therapeutic agents for NB stage 4 and estrogen replacement therapy should be considered as risk factors for the development of FNH.

Variable MR imaging appearances of focal nodular hyperplasia in pediatric cancer patients

BACKGROUND

Focal nodular hyperplasia (FNH) is rare in the general pediatric population but is increasingly found in treated pediatric cancer patients. FNH can be incidentally found on CT and MRI and can be misdiagnosed as liver metastasis in patients with an oncological history.

OBJECTIVE

To describe the MR imaging findings of FNH in pediatric cancer patients.

MATERIALS AND METHODS

Ten children who had been treated for a primary malignancy and who were diagnosed with FNH from 2003 to 2010 were identified from a search for FNH in our pathology and radiology databases. Patients were included if they were treated for a primary malignancy and had undergone MR imaging of the liver including T1-weighted, T2-weighted and dynamic contrast-enhanced T1-weighted sequences.

RESULTS

FNH from all patients (n=10) demonstrated typical homogeneous arterial enhancement on MRI. The FNH was often multiple and small (7/10 patients), lacking a central scar, with variable imaging characteristics including signal hyperintensity on both T1- and T2-weighted images (4/10 patients), especially in the setting of hepatic hemosiderosis.

CONCLUSION

FNH has a variable MR appearance in pediatric cancer patients and should be considered in the differential diagnosis of hypervascular liver lesions.

Focal nodular hyperplasia in children, adolescents, and young adults

BACKGROUND

Focal nodular hyperplasia (FNH) is a benign hepatic tumor that is rare in children. In order to understand whether there are differences in the etiology or appearance of FNH in children, we analyzed the clinical information and imaging of pathologically proven cases.

MATERIALS AND METHODS

A pathology database was used to identify all cases of FNH diagnosed at our institution. Each patient's imaging was evaluated for the characteristics of FNH lesions. Clinical information was obtained on each patient.

RESULTS

Thirteen patients with FNH were identified (7 male/6 female, mean age 14.3 years, range 1-27 years). Seven patients (5 male/2 female) had a remote history of childhood malignancy. The time interval between the diagnoses of malignancy and FNH ranged from 9 to 27 years (mean 14.4 years). On imaging, all seven cancer survivors had multiple liver lesions. In the remaining six patients (2 male/4 female), there was no history of malignancy and all but one of these patients had a solitary FNH.

CONCLUSION

Half of the patients with FNH in this study were long-term cancer survivors and each of these patients had multiple masses. Recognizing the features of FNH will aid in diagnosis and appropriate management.

Focal nodular hyperplasia in pediatric patients with and without oncologic history

The diagnosis of FNH is warranted by the possibility of avoiding unnecessary hepatic resections. The 18 patients of our series, 6 of whom were long-term survivors of malignant, non-hepatic tumors, underwent either a biopsy or a complete excision to obtain the diagnosis. The imaging characteristics could not be considered pathognomonic. The lesion remained stable after the biopsy in 8 patients; no complications were observed in other 10 patients who underwent resection of the mass. The outcome of all our patients with or without previous oncological disease was benign.

Multiple progressive focal nodular hyperplasia lesions of liver in a patient with hemosiderosis

Focal nodular hyperplasia (FNH) is the second most common benign lesion of the liver. It is a solitary lesion and usually does not enlarge. We present the magnetic resonance imaging findings of multiple progressive FNH lesions in a patient with hemosiderosis using Gadolinium-EOB-DTPA (Eovist) as a hepatobiliary contrast agent. The possible mechanisms underlying the occurrence and progression of FNH lesions and the potential value of Eovist in characterizing the lesions were discussed.

Focal nodular hyperplasia in children: clinical features and current management practice

BACKGROUND

Although nonoperative management is an accepted practice for most adults with focal nodular hyperplasia (FNH), questions remain about the safety and feasibility of this strategy in children. Our aim was to review the clinical features of children with FNH and determine current management patterns.

METHODS

We reviewed records of all children and adolescents with FNH managed at our institution from 1999 to 2009 and performed a MEDLINE search to identify all published cases of FNH in the pediatric population.

RESULTS

A total of 172 patients with FNH were identified, including 11 at our institution. The median age at diagnosis was 8.7 years and 66% were female. Median tumor size was 6 cm, and 25% had multiple lesions. Thirty-six percent were symptomatic at presentation. Twenty-four percent had a history of malignancy. Management included resection (61%), biopsy followed by observation (21%), and observation alone (18%). Indications for resection included symptoms (48%), inability to rule out malignancy (24%), tumor growth (15%), and biopsy-proven concurrent malignancy (9%).

CONCLUSIONS

Although FNH is a benign lesion that is typically managed nonoperatively in adults, most children with FNH currently undergo resection because of symptoms, increasing size, or inability to confidently rule out malignancy.

A benign liver tumor mimics hepatic metastasis from colon cancer

Background: Liver is the most common distant metastasized organ in advanced colon cancer. Surgical resection of metastatic lesions would offer the best chance of a long-term survival. An accurate diagnosis and evaluation of extent of disease is crucial in the management of liver metastasis. Objective: Report a benign hepatic condition mimicking liver metastasis in a colon cancer patient. Case presentation: A 53-year-old male with an early stage sigmoid colon cancer was treated with sigmoidectomy followed by adjuvant chemotherapy consisting of 5-FU, leucovorin, and oxaliplatin for six months. Annual computerized tomography of abdomen at two years after the surgery revealed three hypervascular nodules in the liver. Investigations including MRI of the liver and whole body FDG-F18 PET/CT demonstrated evidence consistent with non-metastatic liver nodules. Liver biopsy of one of the lesions led to the diagnosis of “focal nodular hyperplasia”. Conclusion: The possible etiology, diagnosis, and further management of this benign liver tumor, the focal nodular hyperplasia became clear.

Focal nodular hyperplasia of the liver: an unusual association with diabetes mellitus in a child and review of literature

Hepatic hemangioma, adenoma and focal nodular hyperplasia are the most frequent benign lesions of the liver, but they are all infrequent among pediatric population. The reports of focal nodular hyperplasia in children have recently increased in number, with many cases associated to drug intake, particularly to chemotherapy. We here describe, to our knowledge, the first case of focal nodular hyperplasia in association with diabetes mellitus in childhood.

Usefulness of power Doppler ultrasonography and superparamagnetic iron oxide enhanced magnetic resonance imaging for diagnosis of focal nodular hyperplasia of the liver after treatment of neuroblastoma

Focal nodular hyperplasia (FNH) of the liver is rare in children, and it is usually diagnosed through a biopsy of the liver or hepatectomy. The authors report a case of a 10-year-old girl with multiple focal nodular hyperplasia lesions of the liver after the completion of tumor therapy for advanced neuroblastoma, and review the usefulness of the combination of power Doppler ultrasonography (US) and superparamagnetic iron oxide (SPIO) enhanced magnetic resonance imaging (MRI) for the diagnosis of FNH without a biopsy of the liver or hepatectomy.

Focal nodular hyperplasia after orthotopic liver transplantation

Focal nodular hyperplasia (FNH) has been well characterized in native livers, but to our knowledge, no cases of FNH have been described in liver allografts. We review the clinicopathological features of 6 FNHs identified in 4 patients after orthotopic liver transplantation. There were 3 male patients and 1 female patient ranging in age from 2 to 63 years. The time from transplant to a diagnosis of FNH ranged from 15 to 118 months. Two patients presented with an incidental solitary liver nodule. One patient presented with 2 liver nodules, and the other patient initially presented with 1 liver nodule and was found to have another nodule at autopsy 6 years later. Two FNHs were seen as an incidental finding at autopsy, and the other 4 were initially identified on ultrasound. Follow-up magnetic resonance imaging and computed tomography scans revealed features atypical for FNH and suspicious for hepatocellular carcinoma. The initial diagnosis of FNH was made by needle core biopsy in 3 cases and at autopsy in 2 cases. The lesions ranged in size from 1.7 to 6.9 cm. Three patients had conditions associated with altered hepatic vascular perfusion; 2 patients had portal vein thrombosis, and 1 had a partial allograft from a living donor. In conclusion, FNH can present as a hepatic nodule after orthotopic liver transplantation and should not be confused with hepatocellular carcinoma. Because of altered hepatic circulation in the posttransplant liver, a diagnosis of FNH would not be unexpected. FNH should be considered in the differential diagnosis of hepatic nodules within the posttransplant liver, especially in patients with known hepatic vascular perfusion abnormalities.

Focal nodular hyperplasia of the liver in longterm survivors of neuroblastoma: how much diagnostic imaging is necessary?

OBJECTIVES

Focal nodular hyperplasia of the liver is a tumor-like lesion, uncommon in children, but it has recently been more frequently observed in children treated for malignant diseases, especially neuroblastoma. The aetiology is unclear, the pathogenesis remains controversial. Focal nodular hyperplasia of the liver is suspected to be a sequela of tumor therapy.

METHODS

Besides the clinical data we evaluated the imaging modalities needed to diagnose focal nodular hyperplasia of the liver in children with neuroblastoma who have been followed in our institution for more than 5 years.

RESULTS

Out of 60 children six developed focal nodular hyperplasia at a median time of 10.5 years after diagnosis of neuroblastoma and 9.4 years after the end of treatment. The diagnosis of focal nodular hyperplasia was based on imaging criteria which are variable in ultrasonography and specific in MRI. Only one child underwent surgical biopsies to rule out liver metastases.

CONCLUSIONS

Longterm survivors of neuroblastoma are at risk of developing focal nodular hyperplasia, especially if they underwent toxic chemotherapy and/or radiotherapy to the liver during initial treatment. The recommended diagnostic imaging tools are ultrasonography for detecting liver lesions and MRI for confirming and characterizing these lesions as focal nodular hyperplasia.

Hepatoblastoma presenting with focal nodular hyperplasia after treatment of neuroblastoma

Focal nodular hyperplasia (FNH) is a benign, poorly understood hepatic tumor that is rare in children. Although there is no evidence for malignant degeneration, FNH can occur adjacent to a malignancy. Here, the case of a 4-year-old boy with a hepatic mass and history of stage IV neuroblastoma is presented. Initial imaging and core-needle biopsy were consistent with FNH. However, after left lateral segmentectomy, pathologic examination revealed a malignant tumor most consistent with small cell undifferentiated hepatoblastoma as well as 3 foci of FNH in the surrounding parenchyma.

Focal nodular hyperplasia-like lesion of the liver in a child previously treated for nephroblastoma

Described herein is the case of an 8-year-old boy who developed a hepatic nodular lesion after having received anti-neoplastic therapy for nephroblastoma. Histological examination of the excised specimen indicated a disordered arrangement of hepatic components with hemangioma-like features. This case was diagnosed as a variant of focal nodular hyperplasia. It is speculated that this hepatic lesion is a late complication of treatment for nephroblastoma and might develop from congenital malformative area of the liver.

Focal nodular hyperplasia of the liver and elevated alpha fetoprotein level in an infant with isolated hemihyperplasia

A case of focal nodular hyperplasia of the liver in a 43-day-old baby girl with isolated hemihyperplasia and elevated serum alpha-fetoprotein is presented. The child referred to our hospital with bilateral renal masses detected by prenatal and postnatal ultrasonography. A mass lesion was detected in segment 6 of liver and was diagnosed as focal nodular hyperplasia. We present this case to emphasize the presence of focal nodular hyperplasia in a patient with isolated hemihypertrophy and elevated serum alpha-fetoprotein level.

Focal nodular hyperplasia of the liver following hematopoietic SCT

Incidental hepatic regenerating nodules rarely occur after haematopoietic SCT (HSCT). Focal nodular hyperplasia (FNH) is one of these unusual benign tumors with characteristic imaging features. To determine the incidence and the outcome of FNH of the liver and improve the understanding of its pathogenesis, we prospectively surveyed a total of 138 patients who had undergone serial prospective pre- and post-transplantation evaluations of iron biomarkers, including ferritin and liver iron concentration assessed by magnetic resonance imaging (MRI). Seventeen patients with a median delay of 6.4 years (2.2-13.6) developed FNH of the liver. All were children at the time of transplantation. MR images were typical for FNH in 16 patients; only one patient needed a confirmatory biopsy. Sixteen had received a myeloablative conditioning; six received a BU-based preparation and 10 TBI. Three patients experienced sinusoidal obstruction syndrome. Neither complication nor malignant transformation has been reported to date. FNH of the liver seems to be a frequent delayed benign complication following HSCT, probably of iatrogenic vascular origin. Basic clinical and diagnostic imaging follow-up is warranted.

Multiple malignant and benign lesions in the liver in a child with adrenocortical carcinoma

We report 4-year-old girl who was diagnosed with adrenocortical carcinoma when she was 2 years old. At the time of diagnosis there were no metastases, but 6 months later multiple liver metastases appeared. Following intensive chemotherapy the metastases resolved completely. Multifocal lesions were detected in the liver by US 16 months later. Their morphology on US and MRI differed from the previous metastases. Histopathological examination confirmed focal nodular hyperplasia. We discuss the origin and the uncommon appearance of multifocal nodular hyperplasia in hormone-active tumours such as adrenocortical carcinoma in children.

Nodular regenerative hyperplasia and focal nodular hyperplasia of the liver mimicking hepatic metastasis in children with solid tumors and a review of literature

Nodular regenerative hyperplasia (NRH) and focal nodular hyperplasia (FNH) of the liver rarely occur in children after completion of tumor therapy. These lesions mimic hepatic metastasis and they must be distinguished from metastatic lesions. The authors present 2 children, one with NRH and one with FNH, after undergoing antineoplastic therapy for non-hepatic childhood solid tumors and discuss their patients in the context of the literature.

Imaging the complications of bone marrow transplantation in children

Bone marrow transplantation is frequently performed to restore hematologic and immunologic competence after chemotherapy and radiation therapy for a range of childhood malignancies, as well as to treat various congenital conditions in which hematologic and immunologic functions are depressed or absent. Potentially devastating complications may occur during the pre-engraftment period after bone marrow transplantation, when marrow aplasia may supervene for several weeks until engraftment occurs, as well as during the post-engraftment period (the 3 months after engraftment) and in subsequent months and years. Complications of bone marrow transplantation may be classified either according to the time interval between transplantation and the occurrence of the complication or according to the organ system affected. The range of complications that may affect the central nervous system and the rest of the body may be detected with ultrasonography, computed tomography, and magnetic resonance imaging. Neurologic, paranasal sinus, pulmonary, and abdominopelvic complications all may be seen after bone marrow transplantation. Graft-versus-host disease and lymphoproliferative disorders also may occur. The increasing use of bone marrow transplantation mandates that the radiologist be familiar with the full range of potential complications and their imaging appearances.