Whole-liver radiotherapy for end-stage colorectal cancer patients with massive liver metastases and advanced hepatic dysfunction

Palliative radiotherapy for multiple liver metastases: a retrospective analysis of 73 cases

BACKGROUND

Whole-liver radiotherapy for diffuse liver metastases can improve symptoms and abnormal liver-related blood data. However, whole-liver radiotherapy is uncommonly used in clinical practice in Japan. Therefore, we aimed to clarify palliative radiotherapy outcomes in Japanese patients with liver metastases.

METHODS

We retrospectively reviewed databases in our institution to identify patients treated with radiotherapy (8 Gy in a single fraction) for multiple liver metastases between December 2014 and April 2021. The endpoints included pain response, liver-related blood data and adverse effects. We investigated aspartate transaminase, alanine transaminase, lactate dehydrogenase, alkaline phosphatase, γ-glutamyl transpeptidase and albumin. The mean values at whole-liver radiotherapy and after 2-4 weeks were compared using the Wilcoxon rank-sum test.

RESULTS

A total of 73 cases in 71 patients were included. The median clinical target volume was 2118 ml (range, 133-7867 ml). Fifty-seven patients (78%) had finished aggressive treatment at the time of radiotherapy. The median follow-up period was 6 weeks. The pain response rate was 64% (18/28). The mean values of five parameters significantly improved 2-4 weeks after radiotherapy compared to those at baseline: aspartate transaminase (118 vs. 83 U/l P < 0.01); alanine transaminase (84 vs. 61 U/l P < 0.01); lactate dehydrogenase (1351 vs. 1007 U/l P = 0.027); alkaline phosphatase (1624 vs. 1216 U/l P < 0.01) and γ-glutamyl transpeptidase (663 vs. 450 U/l P = 0.037). No patients experienced radiation-induced liver disease.

CONCLUSIONS

Palliative radiotherapy is efficient and safe in Japanese patients with liver metastases. These findings will help encourage whole-liver radiotherapy use in Japan.

Novel Use of Low-Dose Radiotherapy to Modulate the Tumor Microenvironment of Liver Metastases

Despite multiple therapeutic approaches, the presence of liver metastases carries a guarded prognosis, urgently necessitating further clinical and scientific research to develop curative interventions. The liver is an immunoprivileged organ that suppresses the effectiveness of immunotherapies in patients with hepatic metastases. Cancer immunotherapies have been successfully bolstered by low-dose radiotherapy (LDRT), which is capable of reprogramming the tumor microenvironment (TME) from an immunosuppressive to an immunostimulatory one. Likewise, LDRT may be able to revoke the immune privilege enjoyed by the liver, permitting successful immunotherapies there. Here, we first review challenges that face the treatment of liver metastases. We next outline emerging preclinical and clinical evidence supporting enhanced systemic tumor control of LDRT in the context of cancer immunotherapy. Finally, we will discuss the rationale of combining liver-directed LDRT with immunostimulatory strategies to overcome immune resistance and achieve better clinical response. This notion is supported by a recent case study in which a patient who had progressed following T cell therapy experienced a complete response after LDRT to the liver.

AMPKα2 knockout enhances tumour inflammation through exacerbated liver injury and energy deprivation-associated AMPKα1 activation

Tissue damage and its associated‐inflammation act as tumour initiators or propagators. AMP‐activated protein kinase (AMPK) is activated by environmental or nutritional stress factors, such as hypoxia, glucose deprivation, and other cell injury factors, to regulate cell energy balance and differentiation. We previously have reported that AMPKα2 deficiency resulted in the energy deprivation in tumour‐bearing liver and the enhanced‐hepatocyte death. In this study, AMPKα2 knockout mice and the liver metastasis model of colon cancer cells were used to address the role of AMPKα isoforms in tumour inflammation. First, we found that the AMPKα2 deficiency exacerbated the liver injury and recruitment of macrophages. Meanwhile, although compensatory expression of AMPKα1 was not significant after AMPKα2 knockout, AMPKα1 phosphorylation was elevated in remnant liver in AMPKα2 knockout mice, which was positively associated with the enhanced energy deprivation in the AMPKα2 deficient mice. Furthermore, the activated AMPKα1 in macrophage contributed to its polarizing to tumour‐associated phenotype. Thus, the enhanced tumour‐associated inflammation and activation of AMPKα1 in the AMPKα2 deficient mice may exacerbate the tumour development by affecting the tumour inflammatory microenvironment. Our study suggests that the two isoforms of AMPKα, AMPKα1 and AMPKα2 play different roles in controlling tumour development.

It is not clear whether and how the energy stress in tumour microenvironment contribute to macrophage polarization. In this study, the authors found that the AMPKα2 deficiency exacerbated the liver injury and recruitment of macrophages, and elevated AMPKα1 phosphorylation in remnant liver. The activated AMPKα1 in macrophages contributed to their polarizing to tumour‐associated phenotype. The finding provides new insights that the two isoforms of AMPKα, AMPKα1 and AMPKα2 play different roles in controlling tumour development.

Phase I trial of radiation therapy and sorafenib in unresectable liver metastases

BACKGROUND AND PURPOSE

To determine maximum tolerated dose (MTD) and toxicities of sorafenib combined with stereotactic radiotherapy (SBRT) or whole liver radiotherapy (WLRT) in patients with liver metastases.

MATERIAL AND METHODS

Eligible patients had unresectable liver metastases. Sorafenib dose was escalated in 2 strata: I - SBRT: effective liver volume irradiated (V_eff)<80% (30-60Gy in 6 fractions); II - WLRT: V_eff>80% (21.6Gy in 6 fractions). Four weeks of sorafenib, with radiotherapy during weeks 2-3, was delivered at 3 escalating dose levels (200-400mg twice daily). Dose limiting toxicity was defined as any grade 3+ liver toxicity, or grade 4+ treatment-related toxicity.

RESULTS

Thirty-three patients were treated: 18 in stratum I (median dose 42Gy), 15 in stratum II. The MTD was not reached. Grade 3+ toxicity was seen in 33% of patients, at a median of 10days. Two deaths from non-classic liver toxicity occurred post WLRT in stratum II. The median overall survival was 22.3 and 5.7months for strata I and II respectively.

CONCLUSIONS

Sorafenib and 21.6Gy in 6 fraction WLRT resulted in unacceptably high rates of liver toxicity. Although sorafenib combined with SBRT was tolerable, the observed efficacy does not merit further clinical evaluation.

Prospective phase II trial of regional hyperthermia and whole liver irradiation for numerous chemorefractory liver metastases from colorectal cancer

Purpose

A prospective phase II trial was conducted to evaluate the effectiveness and toxicity of regional hyperthermia and whole liver irradiation (WLI) for numerous chemorefractory liver metastases from colorectal cancer.

Materials and Methods

Enrolled patients had numerous chemorefractory hepatic metastases from colorectal cancer. Five sessions of hyperthermia and seven fractions of 3-gray WLI were planned. Health-related quality of life (HRQoL) was determined using the Korean version of the European Organization for Research and Treatment of Cancer quality of life questionnaire C-30 and the Functional Assessment of Cancer Therapy-Hepatobiliary version 4.0. Objective and pain response was evaluated.

Results

A total of 12 patients consented to the study and the 10 who received WLI and hyperthermia were analyzed. WLI was completed as planned in nine patients and hyperthermia in eight. Pain response was partial in four patients and stable in four. Partial objective response was achieved in three patients (30.0%) and stable disease was seen in four patients at the 1-month follow-up. One patient died 1 month after treatment because of respiratory failure related to pleural metastasis progression. Other grade III or higher toxicities were detected in three patients; however, all severe toxicities were related to disease progression rather than treatment. No significant difference in HRQoL was noted at the time of assessment for patients who were available for questionnaires.

Conclusion

Combined WLI and hyperthermia were well tolerated without severe treatment-related toxicity with a promising response from numerous chemorefractory hepatic metastases from colorectal cancer.

Microbial influences on hormesis, oncogenesis, and therapy: A review of the literature

Utilization of environmental stimuli for growth is the main factor contributing to the evolution of prokaryotes and eukaryotes, independently and mutualistically. Epigenetics describes an organism's ability to vary expression of certain genes based on their environmental stimuli. The diverse degree of dose-dependent responses based on their variances in expressed genetic profiles makes it difficult to ascertain whether hormesis or oncogenesis has or is occurring. In the medical field this is shown where survival curves used in determining radiotherapeutic doses have substantial uncertainties, some as large as 50% (Barendsen, 1990). Many in-vitro radiobiological studies have been limited by not taking into consideration the innate presence of microbes in biological systems, which have either grown symbiotically or pathogenically. Present in-vitro studies neglect to take into consideration the varied responses that commensal and opportunistic pathogens will have when exposed to the same stimuli and how such responses could act as stimuli for their macro/microenvironment. As a result many theories such as radiation carcinogenesis explain microscopic events but fail to describe macroscopic events (Cohen, 1995). As such, this review shows how microorganisms have the ability to perturb risks of cancer and enhance hormesis after irradiation. It will also look at bacterial significance in the microenvironment of the tumor before and during treatment. In addition, bacterial systemic communication after irradiation and the host's immune responses to infection could explain many of the phenomena associated with bystander effects. Therefore, the present literature review considers the paradigms of hormesis and oncogenesis in order to find a rationale that ties them all together. This relationship was thus characterized to be the microbiome.

Prognostic and predictive value of liver volume in colorectal cancer patients with unresectable liver metastases

PURPOSE

To determine the prognostic and predictive value of liver volume in colorectal cancer patients with unresectable liver metastases.

MATERIALS AND METHODS

Sixteen patients received whole liver radiotherapy (WLRT) between January 1997 and June 2013. A total dose of 21 Gy was delivered in 7 fractions.

RESULTS

The median survival time after WLRT was 9 weeks. In univariate analysis, performance status, serum albumin and total bilirubin level, liver volume and extrahepatic metastases were associated with survival. The mean liver volume was significantly different between subgroups with and without pain relief (3,097 and 4,739 mL, respectively; p = 0.002).

CONCLUSION

A larger liver volume is a poor prognostic factor for survival and also a negative predictive factor for response to WLRT. If patients who are referred for WLRT have large liver volume, they should be informed of the poor prognosis and should be closely observed during and after WLRT.