Transient elastography for non-invasive evaluation of post-transplant liver graft fibrosis in children.

As graft survival in pediatric LT is often affected by progressive fibrosis, numerous centers carry out protocol liver biopsies. Follow-up biopsy protocols differ from center to center, but all biopsies are progressively spaced out, as time from transplant increases. Therefore, there is a need for non-invasive techniques to evaluate graft fibrosis progression in those children who have no clinical or serological signs of liver damage. Indirect markers, such as the APRI, should be relied on with caution because their sensitivity in predicting fibrosis can be strongly influenced by the etiology of liver disease, severity of fibrosis, and patient age. A valid alternative could be TE, a non-invasive technique already validated in adults, which estimates the stiffness of the cylindrical volume of liver tissue, 100-fold the size of a standard needle biopsy sample. The aims of this study were to evaluate the reliability of TE in children after LT and to compare both the TE and the APRI index results with the histological scores of fibrosis on liver biopsies. A total of 36 pediatric LT recipients were studied. All patients underwent both TE and biopsy within a year (median interval -0.012 months) at an interval from LT of 0.36 to 19.47 years (median 3.02 years). Fibrosis was assessed on the biopsy specimens at histology and staged according to METAVIR. There was a statistically significant correlation between TE stiffness values and METAVIR scores (P = .005). The diagnostic accuracy of TE for the diagnosis of significant fibrosis (F ≥ 2) was measured as the area under the curve (AUROC = 0.865), and it demonstrated that the method had a good diagnostic performance. APRI was not so accurate in assessing graft fibrosis when compared to METAVIR (AUROC = 0.592). A liver stiffness cutoff value of 5.6 kPa at TE was identified as the best predictor for a significant graft fibrosis (METAVIR F ≥ 2) on liver biopsy, with a 75% sensitivity, a 95.8% specificity, a 90% positive predictive value, and an 88.5% negative predictive value. These data suggest that TE may represent a non-invasive, reliable tool for the assessment of graft fibrosis in the follow-up of LT children, alerting the clinicians to the indication for a liver biopsy, with the aim of reducing the number of protocol liver biopsies.

Evaluation of Graft Fibrosis, Inflammation, and Donor-specific Antibodies at Protocol Liver Biopsies in Pediatric Liver Transplant Patients: A Single-center Experience.

BACKGROUND: The impact of graft fibrosis and inflammation on the natural history of pediatric liver transplants is still debated. Our objectives were to evaluate the evolution of posttransplant fibrosis and inflammation over time at protocol liver biopsies (PLBs), risk factors for fibrosis, presence of donor-specific antibodies (DSAs), and/or their correlation with graft and recipient factors. METHODS: A single-center, retrospective (2000-2019) cross-sectional study on pediatric liver transplant recipients who had at least 1 PLB, followed by a longitudinal evaluation in those who had at least 2 PLBs, was conducted. Fibrosis was assessed by the Liver Allograft Fibrosis Semiquantitative score, inflammation by the rejection activity index, DSAs by Luminex. RESULTS: A total of 134 PLBs from 94 patients were included. Fibrosis was detected in 87% (30% mild, 45% moderate, and 12% severe), 80% in the portal tracts. There was an increase in fibrosis between the 1-3 and the 4-6 y group (P = 0.01), then it was stable. Inflammation was observed in 44% (30% mild, 13% moderate, and 1% severe), 90% in the portal tracts. Anti-HLA II (IgG) DSAs were detected in 14 of 40 (35%). Portal fibrosis was associated with portal inflammation in the 1-3 y group (P = 0.04). Low immunosuppression levels were correlated with sinusoidal fibrosis (P = 0.04) and DSA positivity (P = 0.006). There was no statistically significant correlation between DSA positivity and the presence of graft fibrosis or inflammation. CONCLUSIONS: This study corroborates the concept of an early evolution of silent graft fibrosis. Suboptimal immunosuppression may play a role in the development of fibrosis and DSAs.

Ultrasound screening for thyroid carcinoma in childhood cancer survivors: a case series.

CONTEXT: Childhood cancer survivors need regular monitoring into young adulthood and beyond, because they are at risk for developing late-onset complications of cancer therapy, including second malignancies. OBJECTIVE: This study focuses on the use of thyroid ultrasound to screen for thyroid carcinoma in a population of childhood cancer survivors. PATIENTS: A total of 129 subjects who had received radiotherapy to the head, neck, or upper thorax for a pediatric cancer were studied in the setting of a long-term follow-up unit. DESIGN: Thyroid ultrasound usually began 5 yr after radiotherapy and was repeated every third year, if negative. Median follow-up time since childhood cancer diagnosis was 15.8 yr (range 6.1-34.8 yr). Solid thyroid nodules were found in 35 patients. Fine-needle aspiration was performed in 19 patients, of which 14 had nodules above 1 cm. MAIN OUTCOME MEASURE: The main outcome measure was the finding of not palpable thyroid cancers. RESULTS: Cytological examination of specimens diagnosed papillary carcinoma in five patients who underwent surgery. The cytological diagnosis of papillary thyroid carcinoma was confirmed in all cases by histological examination. Notably, only two of these patients had palpable nodules; the other three were smaller than 1 cm and were detected only by ultrasound. However, histological examination showed nodal metastases in two of these. CONCLUSIONS: Although ultrasound screening for thyroid cancer in the general population is not cost effective and could lead to unnecessary surgery, due to false positives, we believe that in childhood cancer survivors who received radiotherapy involving the head, neck, or upper thorax, it would be worthwhile.

Ultrasound surveillance for radiation-induced thyroid carcinoma in adult survivors of childhood cancer.

INTRODUCTION: The optimal surveillance strategy to screen for thyroid carcinoma childhood cancer survivors (CCS) at increased risk is still debated. In our clinical practice, beside neck palpation we routinely perform thyroid ultrasound (US). Here we describe the results obtained using this approach. METHODS: We considered all CCS referred to our long term clinic from November 2001 to September 2014. One hundred and ninety-seven patients who had received radiation therapy involving the thyroid gland underwent US surveillance. Thyroid US started 5 years after radiotherapy and repeated every 3 years, if negative. RESULTS: Among 197 CCS previously irradiated to the thyroid gland, 74 patients (37.5%) developed thyroid nodules, and fine-needle aspiration was performed in 35. In 11 patients the cytological examination was suspicious or diagnostic for malignancy (TIR 4/5), whereas a follicular lesion was diagnosed in nine. Patients with TIR 4/5 cytology were operated and in all cases thyroid cancer diagnosis was confirmed. The nine patients with TIR 3 cytology also underwent surgery and a carcinoma was diagnosed in three of them. Prevalence of thyroid cancer was 7.1%. Tumour size ranged between 4 and 25 mm, but six (43%) were classified T3 because of extra-thyroidal extension. Six patients had nodal metastases; in eight patients the tumour was multifocal. At the time of the study all patients are disease free, without evidence of surgery complications. CONCLUSION: Applying our US surveillance protocol, the prevalence of radiation-induced thyroid cancer is high. Histological features of the thyroid cancers diagnosed in our cohort suggest that most of them were clinically relevant tumours.

Utilility of flow cytometry as ancillary study to improve the cytologic diagnosis of thyroid lymphomas.

BACKGROUND: To evaluate the efficacy of the use of flow cytometry (FC) immunophenotyping together with fine-needle aspiration cytology (FNAC) in the diagnosis of thyroid lymphoma. METHODS: FC was performed in parallel with FNAC in 35 samples of suspected thyroid lymphoma over a 12 years period. Results were correlated with histological or molecular findings and follow-up, when available. RESULTS: A final diagnosis of lymphoma was given in 13 of 35 (37.1%) specimens. Among the 22 cases considered negative for lymphoma by FC, 11 were diagnosed as thyroiditis by cytology, 7 as reactive, 2 were anaplastic carcinoma, and 2 cases were considered cytologically suspicious for lymphoma but were not confirmed by further investigations. Histology on core biopsy or molecular analysis was available in 12 of 13 lymphoma cases (92.3%). Data obtained by the combination cytology/FC were confirmed in all cases on histology biopsies. Correlation with histology showed a sensitivity and a specificity of 100% for the combination cytology/FC. CONCLUSIONS: FC is an important additional test that can contribute with cytology to the identification of lymphomas of the thyroid. FC can detect the presence of small neoplastic lymphocyte populations and may contribute to the diagnosis of cases in which the lymphoid infiltrate is difficult to interpret on cytology alone.

Percutaneous US-guided RF thermal ablation for malignant renal tumors: preliminary results in 13 patients.

Minimally invasive treatment for small renal cell carcinoma (RCC) can be necessary in selected patients and, anyway, is desirable. In situ ablation techniques, including RFA, have been developed. The aim of this study is to evaluate the feasibility, safety and short-term local effectiveness of percutaneous US-guided RFA in a small series, as well as mid-term patient outcome. Thirteen patients with a total of 18 tumors (17 small lesions, 35 mm in size or less, and a larger one, 75 mm in size) underwent 19 RFA sessions. Seven patients had a solitary kidney, and three suffered from VHL disease, too. We treated four lesions in a patient with a bilateral tumor. In another patient, three lesions were ablated. Seventeen tumors were RCC; one was a metastasis from lung cancer. Eight lesions were parenchymal, six exophytic, two parenchymal/exophytic, one parenchymal/central and one central. A monopolar RF system with multitined expandable electrode needles was used. The 35-mm lesion underwent two sessions; the 75-mm lesion was treated with transcatheter arterial embolization before RFA. Tumors with complete loss of contrast enhancement at short-term CT (or MR) were considered successfully treated. Percutaneous US-guided RFA was always feasible without major complications. The success rate after a single treatment in tumors less than 35 mm in size was 88.2% (15/17) and rose to 94.1% (16/17) after the second treatment of the largest lesion. After a mean 14-month follow-up, no successfully treated lesions recurred locally. Only the patient with metastasis from lung cancer died from disease progression in a further location, while all other patients are alive, with renal function still sufficient to avoid dialysis. US guidance allows an easy and safe percutaneous approach for RFA of small non-parahilar RCC. The treatment is locally effective and can be proposed as a minimally invasive therapy for patients with contraindications to surgery or to those expressing an informed consent. Based on the results of this study and of the literature, mid-term results on the clinical usefulness are very encouraging.