Hepatic Resection for Disappearing Liver Metastasis: a Cost-Utility Analysis

Disappearing liver metastases: A systematic review of the current evidence

Advances in systemic chemotherapy have resulted in a significant increase in the reported response rates of colorectal liver metastases (CRLM) over time. Although radiologic response is usually prognostic of favorable outcomes, complete shrinkage of CRLM after chemotherapy, namely "disappearing liver metastases" (DLMs) poses significant therapeutic dilemmas. A systematic review of the literature was conducted to evaluate the existing evidence on the imaging and management of patients with DLMs using the PubMed (Medline), Embase and Cochrane library through December 21st, 2018. The following algorithm was used: "(disappearing OR vanishing OR missing OR (residual tiny)) AND ((liver OR hepatic) AND (metastasis OR metastases OR metastatic OR secondary))." From the 225 records retrieved, 15 studies were finally deemed eligible. A total of 479 patients with DLMs with a median age of 59.5 years (range, 30-83) were identified. Median number of DLM per patient ranged from 1 to 8.8. Median size of LMs prior to chemotherapy was 1.07 cm (range 0.3-3.5). The systemic treatment used to achieve DLMs included systemic chemotherapy alone (only 2 studies) or in combination with targeted agents (11 studies). The median number of chemotherapy cycles in the included studies was 7.8 (range 6-12). Identified factors predisposing to the development of DLM were small size (<2 cm), increased number of treatment cycles, oxaliplatin-based therapy, increased number of CRLM (≥3) and synchronous CRLM. Baseline and preoperative MRI with iv contrast showed the highest sensitivity for DLM detection. Fiducial placement facilitated pre- and intra-operative identification of DLM. Although resection of DLM decreased the local recurrence risk, there was no clearly demonstrated survival benefit after resecting all sites of disappearing lesions. Future randomized clinical trials are highly encouraged to provide strict, evidence-based recommendations for the treatment of patients with DLM.

Predictive factors for bile leakage after hepatectomy for hepatic tumors: a retrospective multicenter study with 631 cases at Yokohama Clinical Oncology Group (YCOG)

BACKGROUND

International Study Group of Liver Surgery (ISGLS) proposed the standardized definition for bile leakage (BL) after hepatectomy (Hx) at 2011 to precisely perceive incidence and predictive factors of this critical condition.

METHODS

We conducted a multicenter retrospective study using the ISGLS definition of BL after Hx.

RESULTS

Perioperative data regarding 631 patients undergoing elective Hx for hepatic tumors without biliary reconstruction performed between January 2009 and December 2011 were analyzed. BL was observed in 30 patients (4.8%). (Grade A, 8 (1.3%); B, 21(3.3%); C, 1 (0.2%)). Five independent predictors (diagnosis of liver metastases, prolonged operation, high risk procedures defined as Hx with broad exposure of the hilar Glissonean sheath, low platelet count and high serum total bilirubin on postoperative day 1) for grade B/C BL were elucidated by the multivariate analysis. When the study cohorts were divided into groups by number of accompanying these predictors, the more the accompanying independent predictors, the higher the incidence of BL. Notably, incidence of BL exceeded 40% in patients with four or more of these predictors.

CONCLUSIONS

Risk stratification for BL after Hx can be achievable using independent predictors clarified in this study. However, proper management for high risk patients remains to be elucidated.

Liver Resection for Breast Cancer Liver Metastases: A Cost-utility Analysis

OBJECTIVE

To estimate the cost-effectiveness of liver resection followed by adjuvant systemic therapy relative to systemic therapy alone for patients with breast cancer liver metastasis.

BACKGROUND

Data on cost-effectiveness of liver resection for advanced breast cancer with liver metastasis are lacking.

METHODS

A decision-analytic Markov model was constructed to evaluate the cost-effectiveness of liver resection followed by postoperative conventional systemic therapy (strategy A) versus conventional therapy alone (strategy B) versus newer targeted therapy alone (strategy C). The implications of using different chemotherapeutic regimens based on estrogen receptor and human epidermal growth factor receptor 2 status was also assessed. Outcomes included quality-adjusted life months (QALMs), incremental cost-effectiveness ratio, and net health benefit (NHB).

RESULTS

NHB of strategy A was 10.9 QALMs compared with strategy B when letrozole was used as systemic therapy, whereas it was only 0.3 QALMs when docetaxel + trastuzumab was used as a systemic therapy. The addition of newer biological agents (strategy C) significantly decreased the cost-effectiveness of strategy B (conventional systemic therapy alone). The NHB of strategy A was 31.6 QALMs versus strategy C when palbociclib was included in strategy C; similarly, strategy A had a NHB of 13.8 QALMs versus strategy C when pertuzumab was included in strategy C. Monte-Carlo simulation demonstrated that the main factor influencing NHB of strategy A over strategy C was the cost of systemic therapy.

CONCLUSIONS

Liver resection in patients with breast cancer liver metastasis proved to be cost-effective when compared with systemic therapy alone, particularly in estrogen receptor-positive tumors or when newer agents were used.

Use of Intermediate Endpoints in the Economic Evaluation of New Treatments for Advanced Cancer and Methods Adopted When Suitable Overall Survival Data are Not Available

OBJECTIVES

This study assessed the use of intermediate endpoints in the economic evaluation of new treatments for advanced cancer and the methodological approaches adopted when overall survival (OS) data are unavailable or of limited use.

METHODS

A systematic literature review was conducted to identify economic evaluations of treatments for advanced cancer published between 2003 and 2013. Cost-effectiveness and cost-utility analyses expressed in cost per life-year gained and cost per quality-adjusted life-year using an intermediate endpoint as an outcome measure were eligible. Characteristics of selected studies were extracted and comprised population, treatment of interest, comparator, line of treatment, study perspective, and time horizon. Use of intermediate endpoints and methods adopted when OS data were lacking were analyzed.

RESULTS

In total, 7219 studies were identified and 100 fulfilled the eligibility criteria. Intermediate endpoints mostly used were progression-free survival and time to progression, accounting for 92 % of included studies. OS data were unavailable for analysis in nearly 25 % of economic evaluations. In the absence of OS data, studies most commonly assumed an equal risk of death for all treatment groups. Other methods included use of indirect comparison based on numerous assumptions, use of a proxy for OS, consultation with clinical experts, and use of published external information from different treatment settings.

CONCLUSION

Intermediate endpoints are widely used in the economic evaluation of new treatments for advanced cancer in order to estimate OS. Currently, different methods are used in the absence of suitable OS data and the choice of an appropriate method depends on many factors including the data availability.

Magnetic Resonance Imaging of Liver Metastasis

Liver magnetic resonance imaging (MRI) is becoming the gold standard in liver metastasis detection and treatment response assessment. The most sensitive magnetic resonance sequences are diffusion-weighted images and hepatobiliary phase images after Gd-EOB-DTPA. Peripheral ring enhancement, diffusion restriction, and hypointensity on hepatobiliary phase images are hallmarks of liver metastases. In patients with normal ultrasonography, computed tomography (CT), and positron emission tomography (PET)-CT findings and high clinical suspicion of metastasis, MRI should be performed for diagnosis of unseen metastasis. In melanoma, colon cancer, and neuroendocrine tumor metastases, MRI allows confident diagnosis of treatment-related changes in liver and enables differential diagnosis from primary liver tumors. Focal nodular hyperplasia-like nodules in patients who received platinum-based chemotherapy, hypersteatosis, and focal fat can mimic metastasis. In cancer patients with fatty liver, MRI should be preferred to CT. Although the first-line imaging for metastases is CT, MRI can be used as a problem-solving method. MRI may be used as the first-line method in patients who would undergo curative surgery or metastatectomy. Current limitation of MRI is low sensitivity for metastasis smaller than 3mm. MRI fingerprinting, glucoCEST MRI, and PET-MRI may allow simpler and more sensitive diagnosis of liver metastasis.