Does adjuvant radiotherapy suppress liver regeneration after partial hepatectomy?

A Prospective Study of Liver Regeneration After Radiotherapy Based on a New (Su'S) Target Area Delineation

Background

In this study, we designed a new (Su’S) target area delineation to protect the normal liver during liver regeneration and prospectively evaluate liver regeneration after radiotherapy, as well as to explore the clinical factors of liver regeneration and established a model and nomogram.

Methods

Thirty patients treated with preoperative downstaging radiotherapy were prospectively included in the training cohort, and 21 patients treated with postoperative adjuvant radiotherapy were included in the validation cohort. The cut-off points of each optimal predictor were obtained using receiver-operating characteristic analysis. A model and nomogram for liver regeneration after radiotherapy were developed and validated.

Results

After radiotherapy, 12 (40%) and 13 (61.9%) patients in the training and validation cohorts experienced liver regeneration, respectively. The risk stratification model based on the cutoffs of standard residual liver volume spared from at least 20 Gy (SVs20 = 303.4 mL/m²) and alanine aminotransferase (ALT=43 u/L) was able to effectively discriminate the probability of liver regeneration. The model and nomogram of liver regeneration based on SVs20 and ALT showed good prediction performance (AUC=0.759) in the training cohort and performed well (AUC=0.808) in the validation cohort.

Conclusions

SVs20 and ALT were optimal predictors of liver regeneration. This model may be beneficial to the constraints of the normal liver outside the radiotherapy-targeted areas.

Locoregional recurrence after curative intent resection for intrahepatic cholangiocarcinoma: implications for adjuvant radiotherapy

BACKGROUNDS

As for intrahepatic cholangiocarcinoma, the most frequent site of failure after curative intent resection is the liver. We identified the risk factors for locoregional recurrence after curative intent resection for intrahepatic cholangiocarcinoma.

METHODS

Medical records of 115 patients treated with surgical resection alone for intrahepatic cholangiocarcinoma from November 2000 to December 2010 were retrospectively reviewed. Locoregional failure was defined as recurrence within 20 mm from resection margin or regional lymph node. Overall survival and locoregional recurrence rates were analyzed using Kaplan-Meier methods, and the prognostic factors were analyzed using Cox proportional hazards model.

RESULTS

Median follow-up duration of surviving patients was 61 months (range 8-139). Sixty-six patients had recurrence, and 45 of 66 patients (68 %) had locoregional recurrence. The 5-year overall survival and locoregional control rates were 49.1 and 51.6 %, respectively. ≥ T2b disease and R1 resection were associated with locoregional recurrence in multivariate analysis. Patients were divided into two groups whether these risk factors exist or not. The 5-year locoregional control rates of low (no risk factor n = 64) and high (1 or 2 risk factors n = 51) risk groups were 62.5 and 34.7 %, respectively (P = 0.001).

CONCLUSIONS

After curative intent resection, locoregional control and survival of patients with intrahepatic cholangiocarcinoma were far from satisfactory. Further studies are needed to evaluate the potential benefit of adjuvant locoregional treatment such as radiotherapy for patients with high-risk factors (≥ T2b disease or R1 resection).

Changes of the liver volume and the Child-Pugh score after high dose hypofractionated radiotherapy in patients with small hepatocellular carcinoma

Purpose

To investigate the safety of high dose hypofractionated radiotherapy (RT) in patients with small hepatocellular carcinoma (HCC) in terms of liver volumetric changes and clinical liver function.

Materials and Methods

We retrospectively reviewed 16 patients with small HCC who were treated with high dose hypofractionated RT between 2006 and 2009. The serial changes of the liver volumetric parameter were analyzed from pre-RT and follow-up (FU) computed tomography (CT) scans. We estimated linear time trends of whole liver volume using a linear mixed model. The serial changes of the Child-Pugh (CP) scores were also analyzed in relation to the volumetric changes.

Results

Mean pre-RT volume of entire liver was 1,192.2 mL (range, 502.6 to 1,310.2 mL) and mean clinical target volume was 14.7 mL (range, 1.56 to 70.07 mL). Fourteen (87.5%) patients had 4 FU CT sets and 2 (12.5%) patients had 3 FU CT sets. Mean interval between FU CT acquisition was 2.5 months. After considering age, gender and the irradiated liver volume as a fixed effects, the mixed model analysis confirmed that the change in liver volume is not significant throughout the time course of FU periods. Majority of patients had a CP score change less than 2 except in 1 patient who had CP score change more than 3.

Conclusion

The high dose hypofractionated RT for small HCC is relatively safe and feasible in terms of liver volumetric changes and clinical liver function.