Successful management and technical aspects of major liver resection in children: A retrospective cohort study

Liver Late Effects in Childhood Cancer Survivors Treated With Radiation Therapy: A PENTEC Comprehensive Review

PURPOSE

A pediatric normal tissue effects in the clinic (PENTEC) comprehensive review of patients with childhood cancer who received radiation therapy (RT) to the liver was performed to develop models that may inform RT dose constraints for the liver and improve risk forecasting of toxicities.

METHODS AND MATERIALS

A systematic literature search was performed to identify published data on hepatic toxicities in children. Treatment and outcome data were extracted and used to generate normal tissue complication probability (NTCP) models. Complications from both whole and partial liver irradiation were considered. For whole liver irradiation, total body irradiation and non-total body irradiation treatments were considered, but it was assumed that the entire liver received the prescribed dose. For partial liver irradiation, only Wilms tumor flank field RT could be analyzed. However, a prescribed dose assumption could not be applied, and there was a paucity of analyzable liver dosimetry data. To associate the dose-volume exposures with the partial volume complication data from flank irradiation, liver dose-volume metrics were reconstructed for Wilms tumor flank RT using age-specific computational phantoms as a function of field laterality and superior extent of the field.

RESULTS

The literature search identified 2103 investigations pertaining to hepatic sinusoidal obstructive syndrome (SOS) and liver failure in pediatric patients. All abstracts were screened, and 241 articles were reviewed in full by the study team. A model was developed to calculate the risk of developing SOS after whole liver RT. RT dose (P = .006) and receipt of nonalkylating chemotherapy (P = .01) were significant. Age <20 years at time of RT was borderline significant (P = .058). The model predicted a 2% risk of SOS with zero RT dose, 6.1% following 10 Gy, and 14.5% following 20 Gy to the whole liver (modeled as the linear-quadratic equivalent dose in 2-Gy fractions [α/β = 3 Gy]). Patients with Wilms tumor treated with right flank RT had a higher observed rate of SOS than patients receiving left flank RT, but data were insufficient to generate an NTCP model for partial liver irradiation. From the phantom-based dose reconstructions, mean liver dose was estimated to be 2.16 ± 1.15 Gy and 6.54 ± 2.50 Gy for left and right flank RT, respectively, using T10-T11 as the superior field border and a prescription dose of 10.8 Gy (based on dose reconstruction). Data were sparse regarding rates of late liver injury after RT, which suggests low rates of severe toxicity after treatment for common pediatric malignancies.

CONCLUSIONS

This pediatric normal tissue effects in the clinic (PENTEC) review provides an NTCP model to estimate the risk of hepatic SOS as a function of RT dose following whole liver RT and quantifies the range of mean liver doses from typical Wilms tumor flank irradiation fields. Patients treated with right flank RT had higher rates of SOS than patients treated with left flank RT, but data were insufficient to develop a model for partial liver irradiation. Risk of SOS was estimated to be approximately ≤6% in pediatric patients receiving whole liver doses of <10 Gy.

Parenchyma Sparing Anatomic Liver Resections (Bi- and Uni-Segmentectomies) for Liver Tumours in Children-A Single-Centre Experience

Purpose: To present a single-centre experience in bi- and uni-segmentectomies for primary liver tumours in children.

METHODS

This study included 23 patients that underwent (bi)segmentectomy. There were 15 malignant tumours (hepatoblastoma-13 patients), 7 benign tumours, and 1 calcifying nested stromal epithelial tumour.

RESULTS

The median tumour diameter was 52 mm (range 15-170 mm). Bisegmentectomy 2-3 was most frequently performed (seven patients), followed by bisegmentectomy 5-6 (four patients). The median operative time was 225 min (range 95-643 min). Intraoperative complications occurred in two patients-small bowel perforation in one and an injury of the small peripheral bile duct resulting in biloma in the other. The median resection margin in patients with hepatoblastoma was 3 mm (range 1-15 mm). Microscopically negative margin status was achieved in 12 out of 13 patients. There were two recurrences. After a median follow-up time of 38 months (range 12-144 months), all 13 patients with HB were alive with no evidence of disease. Two relapsed patients were alive with no evidence of disease.

CONCLUSIONS

From the available literature and data presented here, we propose that (bi)segmentectomy can become a viable surgical option in carefully selected paediatric patients and is sufficient to achieve a cure. Further studies evaluating the impact of parenchymal preservation surgery on surgical and oncological outcome should be conducted with a larger dataset.

Evidence on Indications and Techniques to Increase the Future Liver Remnant in Children Undergoing Extended Hepatectomy: A Systematic Review and Meta-Analysis of Individual Patient Data

BACKGROUND

Techniques to increase the future liver remnant (FLR) have fundamentally changed the indications and criteria of resectability in adult liver surgery. In pediatric patients however, these procedures have rarely been applied and the potential benefit or harm as well as suited indications are unclear.

METHODS

A systematic literature search of MEDLINE, Web of Science, and CENTRAL was conducted. Based on a PRISMA-compliant, predefined methodology, all studies reporting pediatric patients (< 18y) undergoing liver resection with either associating liver partition and portal vein ligation for stages hepatectomy (ALPPS) or preoperative portal vein embolization or ligation (PVE/PVL) were included. Baseline data, periinterventional morbidity, increase of FLR and outcomes were analyzed.

RESULTS

15 studies reporting on 21 pediatric patients with a mean age of 4 years and 7 months (range 1.8 months - 17 years) were included. 12 ALPPS procedures, 8 PVE and 1 PVL were performed. The applied criteria for performing ALPPS or PVE were heterogenous and thresholds for minimally acceptable FLR varied. Mean FLR [% of total liver volume] before the intervention was 23.6% (range 15.0 - 39.3%) in the ALPPS group and 31.4% (range 21.5 - 56.0%) in the PVE group. Mean increase of FLR before stage 2 resection was 69.4% (range 19.0 - 103.8%) for ALPPS and 62.8% (range 25.0 - 108.0%) after PVE. No postoperative death occurred, one early intrahepatic recurrence after an ALPPS procedure was reported. Overall postoperative morbidity was 23.8%.

CONCLUSION

Validated criteria for minimal FLR in pediatric liver resection are lacking and so are clear indications for ALPPS or PVE. In special cases, ALPPS and PVE can be valuable techniques to achieve complete resection of pediatric liver tumors. However, more data are needed, and future studies should focus on a definition and validation of posthepatectomy liver failure as well as the minimally needed FLR in pediatric patients undergoing extended hepatectomy.

SYSTEMATIC REVIEW REGISTRATION

[www.clinicaltrials.gov], identifier [PROSPERO 2021 CRD42021274848].