Focal nodular hyperplasia in oncology 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.

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.

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 of the liver in patients previously treated for pediatric neoplastic diseases

The discovery of a liver nodule during postcancer follow-up suggests malignancy recurrence. However, patients previously treated for pediatric cancers are at greater risk of developing benign hepatic tumors, raising the problems of getting an accurate noninvasive diagnosis. Here we report 3 cases of focal nodular hyperplasia of the liver in patients previously treated for pediatric neoplastic diseases. Radiologic findings and needle-biopsies remained insufficient in 2 cases to rule out metastasis or a potentially threatening tumor. Only surgical resection led to positive diagnosis and prevented complications. However, a review of the literature shows that if the nodule presents with typical features of focal nodular hyperplasia a close imaging follow-up is all that is recommended.

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.