03:00 PM Abstract No. 411 A slice of normal liver in pediatric liver tumors: do we need it?

Abstract

Histologic evaluation of focal liver disease and mass lesions can be challenging. In a pediatric population, inadequate sampling or unclear diagnosis can lead to repeat biopsies that require general anesthesia. Adding non-lesional liver tissue (NLT) or transitional liver tissue (TLT) to standard biopsy procedures may aid pathologists in reaching a diagnosis. We aim to evaluate the safety, outcomes, and utility of adding NLT/TLT to evaluate pediatric liver lesions. Chart review revealed 36 liver lesion biopsies occurred from January 2016 to July 2018 at a tertiary care children’s hospital. Results were screened for NLT and TLT cases with exclusion of transplant patients (n=14). TLT was defined as the interface between radiologically NLT and the lesion of concern. A non-lesional liver sample was obtained using a 16- or 18-gauge coaxial system, before positioning the needle into the lesion. Among 10 boys and 4 girls (mean age 9.0 years, range 1–19 years), fine-needle aspiration (FNA) (mean 2.1 FNAs per procedure), NLT core biopsy (mean 1.6 cores), TLT core biopsy (mean 2.0 cores), and lesional core biopsy (mean 5.9 cores) were performed. NLT/TLT sample utility was subjectively evaluated by a pathologist. NLT was abnormal in 3 patients and normal in 11 patients. The pathologist reviewing these patients found NLT/TLT helpful in all cases, even if the tissue was normal. Only a single case (7.1%) required 2 separate incisions to obtain NLT and lesional tissue. On average, 2.6 additional core biopsies were performed to obtain NLT or TLT. All biopsies led to a final diagnosis without further tissue sampling. Pre- and post-procedural hemoglobin demonstrated no significant changes over 24 hours (p>.05). No intraprocedural or post-procedural complications were observed. In one case, comparison of NLT to the lesion enabled pathologists to identify malignant features within the NLT, aiding in the diagnosis of early metastatic neuroendocrine tumor. Obtaining additional NLT/TLT during a liver mass biopsy is not only safe, but also beneficial in making an accurate diagnosis. However this study is limited due to the small sample size and possible subjective bias of pathologists.