Treating patients with colon cancer liver metastasis: a nationwide analysis of therapeutic decision making

Surgical Resection of Colorectal Liver Metastases: Attitudes and Practice Patterns in the Deep South

BACKGROUND

Metastatic disease is the leading cause of mortality in colorectal cancer. Resection of colorectal liver metastases, when possible, is associated with improved long-term survival and the possibility of cure. However, nationwide studies suggest that liver resection is under-utilized in the treatment of colorectal liver metastases. This study was undertaken to understand attitudes and practice patterns among medical oncologists in the Deep South.

METHODS

A survey of medical oncologists in the states of Alabama, Mississippi, and the Florida panhandle was performed. Respondents were queried regarding perceptions of resectability and attitudes towards surgical referral.

RESULTS

We received 63 responses (32% response rate). Fifty percent of respondents reported no liver surgeons in their practice area. Commonly perceived contraindications to liver resection included extrahepatic metastatic disease (72%), presence of > 4 metastases (72%), bilobar metastases (61%), and metastases > 5 cm (46%). Bilobar metastatic disease was perceived as a contraindication more frequently by non-academic medical oncologists (70% vs. 33%, p = 0.03).

CONCLUSIONS

Wide variations exist in perceptions of resectability and referral patterns for colorectal liver metastases among surveyed medical oncologists. There is a need for wider dissemination of resectability criteria and more liver surgeon involvement in the management of patients with colorectal liver metastases.

Public preferences for delayed or immediate antibiotic prescriptions in UK primary care: A choice experiment

BACKGROUND

Delayed (or "backup") antibiotic prescription, where the patient is given a prescription but advised to delay initiating antibiotics, has been shown to be effective in reducing antibiotic use in primary care. However, this strategy is not widely used in the United Kingdom. This study aimed to identify factors influencing preferences among the UK public for delayed prescription, and understand their relative importance, to help increase appropriate use of this prescribing option.

METHODS AND FINDINGS

We conducted an online choice experiment in 2 UK general population samples: adults and parents of children under 18 years. Respondents were presented with 12 scenarios in which they, or their child, might need antibiotics for a respiratory tract infection (RTI) and asked to choose either an immediate or a delayed prescription. Scenarios were described by 7 attributes. Data were collected between November 2018 and February 2019. Respondent preferences were modelled using mixed-effects logistic regression. The survey was completed by 802 adults and 801 parents (75% of those who opened the survey). The samples reflected the UK population in age, sex, ethnicity, and country of residence. The most important determinant of respondent choice was symptom severity, especially for cough-related symptoms. In the adult sample, the probability of choosing delayed prescription was 0.53 (95% confidence interval (CI) 0.50 to 0.56, p < 0.001) for a chesty cough and runny nose compared to 0.30 (0.28 to 0.33, p < 0.001) for a chesty cough with fever, 0.47 (0.44 to 0.50, p < 0.001) for sore throat with swollen glands, and 0.37 (0.34 to 0.39, p < 0.001) for sore throat, swollen glands, and fever. Respondents were less likely to choose delayed prescription with increasing duration of illness (odds ratio (OR) 0.94 (0.92 to 0.96, p < 0.001)). Probabilities of choosing delayed prescription were similar for parents considering treatment for a child (44% of choices versus 42% for adults, p = 0.04). However, parents differed from the adult sample in showing a more marked reduction in choice of the delayed prescription with increasing duration of illness (OR 0.83 (0.80 to 0.87) versus 0.94 (0.92 to 0.96) for adults, p for heterogeneity p < 0.001) and a smaller effect of disruption of usual activities (OR 0.96 (0.95 to 0.97) versus 0.93 (0.92 to 0.94) for adults, p for heterogeneity p < 0.001). Females were more likely to choose a delayed prescription than males for minor symptoms, particularly minor cough (probability 0.62 (0.58 to 0.66, p < 0.001) for females and 0.45 (0.41 to 0.48, p < 0.001) for males). Older people, those with a good understanding of antibiotics, and those who had not used antibiotics recently showed similar patterns of preferences. Study limitations include its hypothetical nature, which may not reflect real-life behaviour; the absence of a "no prescription" option; and the possibility that study respondents may not represent the views of population groups who are typically underrepresented in online surveys.

CONCLUSIONS

This study found that delayed prescription appears to be an acceptable approach to reducing antibiotic consumption. Certain groups appear to be more amenable to delayed prescription, suggesting particular opportunities for increased use of this strategy. Prescribing choices for sore throat may need additional explanation to ensure patient acceptance, and parents in particular may benefit from reassurance about the usual duration of these illnesses.

Impact of Neoadjuvant Chemotherapy on the Postoperative Outcomes of Patients Undergoing Liver Resection for Colorectal Liver Metastases: A Population-Based Propensity-Matched Analysis

BACKGROUND

The role of neoadjuvant chemotherapy in the management of colorectal liver metastases remains controversial. We sought to investigate whether neoadjuvant systemic chemotherapy contributes to clinically significant increases in postoperative morbidity and mortality using a population-based cohort.

STUDY DESIGN

The American College of Surgeons NSQIP Targeted Hepatectomy Participant Use Files were queried from 2014 to 2016 to identify patients with colorectal liver metastases who underwent liver resection. Patients were stratified by receipt of neoadjuvant chemotherapy using propensity score matching. Univariate and multivariable analyses were used to characterize the effect of neoadjuvant chemotherapy on perioperative morbidity and mortality.

RESULTS

After propensity score matching, 1,416 (50%) patients received neoadjuvant chemotherapy before hepatectomy and 1,416 (50%) underwent liver resection without neoadjuvant chemotherapy. There were no differences in age (60 vs 61 years), maximum tumor size (≤5 cm: 79% vs 80%, >5 cm: 21% vs 20%), resection type (partial hepatectomy: 69% vs 70%), simultaneous colectomy (9% vs 9%), or use of preoperative portal vein embolization (5% vs 5%) in those undergoing neoadjuvant chemotherapy compared with those who did not (all, p > 0.05). Overall 30-day postoperative morbidity (34% vs 33%), including rates of biliary fistula (6% vs 5%), post-hepatectomy liver failure (5% vs 5%), and mortality rates (0.8% vs 0.7%), were similar among patients who received neoadjuvant chemotherapy vs those who did not (all, p > 0.05). On multivariable analysis, receipt of neoadjuvant chemotherapy was not associated with increased morbidity (odds ratio 1.07; 95% CI 0.90 to 1.27; p = 0.43) or mortality (odds ratio 1.09; 95% CI 0.44 to 2.72; p = 0.85).

CONCLUSIONS

In this propensity-matched population-based cohort study, the use of neoadjuvant systemic chemotherapy was not associated with higher rates of complications, biliary fistula, post-hepatectomy liver failure, or mortality among patients with colorectal liver metastases undergoing liver resection.

Assessing resectability of colorectal liver metastases: How do different subspecialties interpret the same data?

BACKGROUND

Multimodal treatment of colorectal liver metastases (CRLMs) relies on precise upfront assessment of resectability. Variability in the definition of resectable disease and the importance of early consultation by a liver surgeon have been reported. In this pilot study we investigated the initial resectability assessment and patterns of referral of patients with CRLMs.

METHODS

Surgeons and medical oncologists involved in the management of colorectal cancer at 2 academic institutions and affiliated community hospitals were surveyed. Opinions were sought regarding resectability of CRLMs and the type of initial specialty referral (hepatobiliary surgery, medical oncology, palliative care or other) in 6 clinical cases derived from actual cases of successfully performed 1- or 2-stage resection/ablation of hepatic disease. Case scenarios were selected to illustrate critical aspects of assessment of resectability, best therapeutic approaches and specialty referral. Standard statistical analyses were performed.

RESULTS

Of the 75 surgeons contacted, 64 responded (response rate 85%; 372 resectability assessments completed). Hepatic metastases were more often considered resectable by hepatobiliary surgeons than all other respondents (92% v. 57%, p < 0.001). Upfront systemic therapy was most commonly prioritized by surgical oncologists (p = 0.01). Hepatobiliary referral was still considered in 73% of "unresectable" assessments by colorectal surgeons, 59% of those by general surgeons, 57% of those by medical oncologists and 33% of those by surgical oncologists (p = 0.1).

CONCLUSION

Assessment of resectability varied significantly between specialties, and resectability was often underestimated by nonhepatobiliary surgeons. Hepatobiliary referral was not considered in a substantial proportion of cases erroneously deemed unresectable. These disparities result largely from an imprecise understanding of modern surgical indications for resection of CRLMs.

Lymphadenectomy for Intrahepatic Cholangiocarcinoma: Has Nodal Evaluation Been Increasingly Adopted by Surgeons over Time?A National Database Analysis

BACKGROUND

Surgical management of intrahepatic cholangiocarcinoma routinely includes resection of the hepatic parenchyma, yet the role of lymphadenectomy (LND) is more controversial. The objective of the current study was to define overall utilization, as well as temporal trends, in the utilization of LND among patients undergoing curative-intent hepatectomy for ICC using a nationwide database.

MATERIALS AND METHODS

One thousand four hundred ninety-six patients who underwent curative-intent resection for ICC were identified using the SEER database from 2000 to 2013. The utilization of LND was assessed over time and by geographic region. LND utilization and the incidence of lymph node metastasis (LNM) were evaluated relative to AJCC T categories.

RESULTS

At the time of surgery, slightly over one-half of patients (n = 784, 52.4%) had at least one LN evaluated. Specifically, 613 (41.0%) patients had 1-5 LNs evaluated, whereas 171 (11.4%) patients had ≥ 6 LNs evaluated. The proportion of patients who had at least one LN evaluated at the time of surgery did not change with time (2000-2004: 50.5% vs. 2005-2009: 52.0% vs. 2010-2013: 53.7%) (p = 0.636). In contrast, the proportion of patients who had ≥ 6 LNs examined did increase (2000-2004: 6.9% vs. 2005-2009: 10.6% vs. 2009-2013: 14.3%) (p = 0.003). The risk of LNM was higher among patients with advanced T category tumors (Referent T1; T2a: OR 4.2, 95% CI 2.0-8.8, p < 0.001; T2b: OR 2.4, 95% CI 1.1-4.9, p = 0.018; T3: OR 3.6, 95% CI 1.6-7.9, p = 0.001; T4: OR 2.2, 95% CI 1.0-4.9, p = 0.049). In addition, the portion of patients with LNM varied among the different T categories (T1, 23.2%, T2a, 55.3%, T2b, 42.0%, T3, 51.4%, and T4, 39.5%; p = 0.001).

CONCLUSIONS

Utilization of LND in the surgical management of ICC across the USA remained relatively low and did not change over the last decade. Selective utilization of LND may be problematic as T-stage was not a reliable predictor of nodal status with almost a quarter of patients with early stage disease having LNM.

Personalized treatment in patients with colorectal liver metastases

BACKGROUND

Precision Medicine Initiative is a new research effort aiming to offer personalized treatment in many diseases, including cancer. The aim of the present article is to offer novel insights about the role of personalized treatment in patients with colorectal liver metastases (CRLM).

METHODS

A review of the literature regarding personalized medicine and colorectal liver metastases was performed mainly in the MEDLINE/PubMed database.

RESULTS

Surgical resection remains the only hope for cure of CRLM. Improved surgical strategies to optimize remnant liver volume are recently introduced and gaining ground. Following resection of CRLM scoring systems have been developed by combining certain preoperative factors such as microsatellite instability KRAS expression and sensitivity to immunotherapy with Programmed Death-1 inhibitor.

CONCLUSIONS

Multidisciplinary management of patients with CRLM has markedly contributed to increased survival. While the last several decades have been characterized by these important developments, future advances for patients with CRLM will depend on a better understanding of genomics and molecular biology to facilitate characterization of a specific tumor "identity" so that individualized treatment for each CRLM patient becomes the rule, and not the exception.

Decision-making in rectal and colorectal cancer: systematic review and qualitative analysis of surgeons' preferences

Surgeons are experiencing difficulties implementing recommendations not only owing to incomplete, confusing or conflicting information but also to the increasing involvement of patients in decisions relating to their health. This study sought to establish which common factors including heuristic factors guide surgeons' decision-making in colon and rectal cancers. We conducted a systematic literature review of surgeons' decision-making factors related to colon and rectal cancer treatment. Eleven of 349 identified publications were eligible for data analyses. Using the IRaMuTeQ (Interface of R for the Multidimensional Analyses of Texts and Questionnaire), we carried out a qualitative analysis of the significant factors collected in the studies reviewed. Several validation procedures were applied to control the robustness of the findings. Five categories of factors (i.e. patient, surgeon, treatment, tumor and organizational cues) were found to influence surgeons' decision-making. Specifically, all decision criteria including biomedical (e.g. tumor information) and heuristic (e.g. surgeons' dispositional factors) criteria converged towards the factor 'age of patient' in the similarity analysis. In the light of the results, we propose an explanatory model showing the impact of heuristic criteria on medical issues (i.e. diagnosis, prognosis, treatment features, etc.) and thus on decision-making. Finally, the psychosocial complexity involved in decision-making is discussed and a medico-psycho-social grid for use in multidisciplinary meetings is proposed.

Clinical practice guidelines for the management of metastatic colorectal cancer: a consensus statement of the Hellenic Society of Medical Oncologists (HeSMO)

There is discrepancy and failure to adhere to current international guidelines for the management of metastatic colorectal cancer (CRC) in hospitals in Greece and Cyprus. The aim of the present document is to provide a consensus on the multidisciplinary management of metastastic CRC, considering both special characteristics of our Healthcare System and international guidelines. Following discussion and online communication among the members of an executive team chosen by the Hellenic Society of Medical Oncology (HeSMO), a consensus for metastastic CRC disease was developed. Statements were subjected to the Delphi methodology on two voting rounds by invited multidisciplinary international experts on CRC. Statements reaching level of agreement by ≥80% were considered as having achieved large consensus, whereas statements reaching 60-80% moderate consensus. One hundred and nine statements were developed. Ninety experts voted for those statements. The median rate of abstain per statement was 18.5% (range: 0-54%). In the end of the process, all statements achieved a large consensus. The importance of centralization, care by a multidisciplinary team, adherence to guidelines, and personalization is emphasized. R0 resection is the only intervention that may offer substantial improvement in the oncological outcomes.

Statistical Methods for the Analysis of Discrete Choice Experiments: A Report of the ISPOR Conjoint Analysis Good Research Practices Task Force

Conjoint analysis is a stated-preference survey method that can be used to elicit responses that reveal preferences, priorities, and the relative importance of individual features associated with health care interventions or services. Conjoint analysis methods, particularly discrete choice experiments (DCEs), have been increasingly used to quantify preferences of patients, caregivers, physicians, and other stakeholders. Recent consensus-based guidance on good research practices, including two recent task force reports from the International Society for Pharmacoeconomics and Outcomes Research, has aided in improving the quality of conjoint analyses and DCEs in outcomes research. Nevertheless, uncertainty regarding good research practices for the statistical analysis of data from DCEs persists. There are multiple methods for analyzing DCE data. Understanding the characteristics and appropriate use of different analysis methods is critical to conducting a well-designed DCE study. This report will assist researchers in evaluating and selecting among alternative approaches to conducting statistical analysis of DCE data. We first present a simplistic DCE example and a simple method for using the resulting data. We then present a pedagogical example of a DCE and one of the most common approaches to analyzing data from such a question format-conditional logit. We then describe some common alternative methods for analyzing these data and the strengths and weaknesses of each alternative. We present the ESTIMATE checklist, which includes a list of questions to consider when justifying the choice of analysis method, describing the analysis, and interpreting the results.

Time-to-Surgery and Survival Outcomes in Resectable Colorectal Liver Metastases: A Multi-Institutional Evaluation

BACKGROUND

Resection of colorectal liver metastases (CRLM) is associated with improved survival; however, the impact of time to resection on survival is unknown. The current multi-institutional study sought to evaluate the influence of time from diagnosis (Dx) to resection (Rx) on survival outcomes among patients with resectable, metachronous CRLM and to compare practice patterns across hospitals.

STUDY DESIGN

Medical records of patients with ≤4 metachronous CRLM treated with surgery were reviewed and analyzed retrospectively. Time from Dx to Rx was analyzed as a continuous variable and also dichotomized into 2 groups (group 1: Dx to Rx <3 months and group 2: Dx to Rx ≥3 months) for additional analysis. Survival time distributions after resection were estimated using the Kaplan-Meier method. Between-group univariate comparisons were based on the log-rank test and multivariable analysis was done using Cox proportional hazards model.

RESULTS

From 2000 to 2010, six hundred and twenty-six patients were identified. Type of initial referral (p < 0.0001) and use of neoadjuvant (p = 0.04) and/or adjuvant (p < 0.0001) chemotherapy were significantly different among hospitals. Patients treated with neoadjuvant chemotherapy (n = 108) and those with unresectable disease at laparotomy (n = 5) were excluded from final evaluation. Median overall survival and recurrence-free survival were 74 months (range 63.8 to 84.2 months) and 29 months (range 23.9 to 34.1 months), respectively. For the entire cohort, longer time from Dx to Rx was independently associated with shorter overall survival (hazard ratio = 1.12; 95% CI, 1.06-1.18; p < 0.0001), but not recurrence-free survival. Median overall survival for group 1 was 76 months (range 62.0 to 89.2 months) vs 58 months (range 34.3 to 81.7 months) in group 2 (p = 0.10). Among patients with available data pertaining to adjuvant chemotherapy (N = 457; 318 treated and 139 untreated), overall survival (87 months [range 71.2 to 102.8 months] vs 48 months [range 25.3 to 70.7 months]; p <0.0001), and recurrence-free survival (33 months [range 25.3 to 40.7 months] vs 22 months [range 14.5 to 29.5 months]; p = 0.05) were improved significantly.

CONCLUSIONS

In select patients undergoing initial resection for CRLM, longer time from Dx to Rx is independently associated with worse overall survival. In addition, despite uniform disease characteristics, practice patterns related to definitely resectable CRLM vary significantly across hospitals.

Understanding surgeon decision making in the use of radiotherapy as neoadjuvant treatment in rectal cancer

BACKGROUND

Strong evidence supports the use of neoadjuvant radiotherapy in rectal cancer to improve local control. This randomised controlled trial aimed to determine the effect of clinical and non-clinical factors on decision making by colorectal surgeons in patients with rectal cancer.

METHODS

Two surveys comprising vignettes of alternating short (4) and long (12) cues identified previously as important in rectal cancer, were randomly assigned to all members of the CSSANZ. Respondents chose from three possible treatments: long course chemoradiotherapy (LC), short course radiotherapy (SC) or surgery alone to investigate the effects on surgeon decision and confidence in decisions. Choice data were analysed using multinomial logistic regression models.

RESULTS

106 of 165 (64%) surgeons responded. LC was the preferred treatment choice in 73% of vignettes. Surgeons were more likely to recommend LC over SC (OR 1.79) or surgery alone (OR 1.99) when presented with the shorter, four-cue scenarios. There was no significant difference in confidence in decisions made when surgeons were presented with long cue vignettes (P = 0.57). Significant effects on the choice between LC, SC and surgery alone were tumour stage (P < 0.001), nodal status (P < 0.001), tumour position in the rectum (P < 0.001) and the circumferential location of the tumour (P < 0.001). A T4 tumour was the factor most likely associated with a recommendation against surgery alone (OR 335.96) or SC (OR 61.73).

CONCLUSIONS

This study shows that clinical factors exert the greatest influence on surgeon decision making, which follows a "fast and frugal" heuristic decision making model.

Surgical Resection Preferences and Perceptions among Medical Oncologists Treating Liver Metastases from Colorectal Cancer

BACKGROUND

Liver resection is a key therapeutic strategy to improve survival in patients with colorectal cancer liver metastases. Underutilization may negatively affect outcomes. Using a Web-based survey and standardized imaging scenarios, this study assessed medical oncologists' (MOs) perceptions of resectability, preferences for chemotherapy sequencing, and referral for surgical consultation in a static patient profile of good performance status and no extrahepatic spread but varying bulk and distribution of disease.

METHODS

A total of 190 US-based MOs were surveyed. A single patient profile was created and combined with 10 different sets of liver computed tomographic images displaying a broad spectrum of metastases. Assessments of resectability and ranking were compared with the results obtained from an expert panel of 3 hepatic surgeons.

RESULTS

The expert hepatic surgeons designated 8 scans resectable, 1 borderline resectable/convertible, and 1 unresectable. In the 8 resectable cases, 34.4 % of MOS perceived the case to be initially resectable, 41.7 % potentially resectable after chemotherapy response, and 23.9 % unresectable. Increasing number of lesions, larger tumor diameter, and bilateral disease were associated with lower resectability perception (P < 0.01). Among those cases considered resectable by MOs, they preferred initial resection (54.2 %) over neoadjuvant chemotherapy (38.4 %). Initial referral for surgical consultation was generally favored only for cases considered initially resectable by MOs.

CONCLUSIONS

This study confirms both potential discrepancies between MOs' and hepatic surgeons' perception of resectability and underutilization of early surgical consultation for patients with potentially resectable colorectal cancer liver metastases and underscores the importance of an evaluation that includes an experienced hepatic surgeon.

Patterns of Care for Metastatic Colorectal Cancer in Appalachia, and the Clinical, Sociodemographic, and Service Provider Determinants

BACKGROUND

Appalachia has high colorectal cancer (CRC) incidence and mortality, at least in part due to screening disparities. This paper examines patterns and determinants of metastatic colorectal cancer care.

METHODS

CRC patients diagnosed in 2006-2008 from 4 cancer registries (Kentucky, Ohio, Pennsylvania, and North Carolina) were linked to Medicare claims (2005-2009.) The final sample after exclusions included 855 stage IV and 590 stages I-III patients with metachronous or synchronous metastases. We estimate bivariate and multivariate analyses for several surgical and chemotherapeutic strategies of care using clinical, sociodemographic, and contextual determinants.

RESULTS

Among 1,445 CRC patients, 84% had primary tumor resection and 44% received chemotherapy. Of the chemotherapy patients, 44% received newer systemic agents for at least 75% of the cycles. One year survivors with liver or lung metastases were more likely to have their primary tumor resected immediately (86.1% vs 69.5% for liver, and 78.2% vs 64.9% for lung) and have their metastases resected/ablated (15.7% vs 2.6% for liver and 15.0% vs 0.5% for lung). Patients with stages I-III primary tumors (versus IV) were much more likely to be resected, but they were less likely to receive chemotherapy. Patients with comorbidities (congestive heart failure, dementia, or respiratory disease) had lower odds of chemotherapy. Smaller hospital size and surgical volume had higher odds of immediate versus delayed surgery. The newer chemotherapeutic agents were more common with higher surgical volume.

CONCLUSIONS

Metastatic colorectal cancer has clinical, sociodemographic, and service provider determinants.

Lymphatic Invasion is an Independent Adverse Prognostic Factor in Patients with Colorectal Liver Metastasis

BACKGROUND

For a selection of patients with colorectal liver metastases (CRLM), liver resection is a curative option. In order to predict long-term survival, clinicopathologic risk scores have been developed, but little is known about histologic factors and their prognostic value for disease-free and overall survival. The objective of the present study was to assess possible prognostic histologic factors in patients with solitary CRLM treated with liver resection who did not receive neoadjuvant treatment.

METHODS

Patients with solitary CRLM who underwent liver resection between 1992 and 2011 were evaluated for clinical prognostic factors. Histologic analyses on tumor thickness at the tumor-normal interface, presence of a fibrotic capsule, intrahepatic vascular invasion, lymphatic invasion, or bile duct invasion and perineural growth were performed, using immunohistochemistry.

RESULTS

A total of 124 patients were analyzed with a median follow-up of 41 months (range 1-232 months). There was no association between histologic factors and disease-free survival in multivariate analysis. In multivariate analysis, intrahepatic lymphatic invasion was associated with a decreased overall survival (41.9 vs. 61.0 months; p = 0.041), especially in combination with vascular invasion (n = 15) (28.1 vs. 62.2 months; p < 0.0001). In addition, size over 50 mm (29.2 vs. 65.9 months; p = 0.004) and interval less than 12 months between resection of the primary tumor and diagnosis of liver metastasis (49.0 vs. 91.5 months: p = 0.019) were also independent adverse prognostic factors.

CONCLUSIONS

Intrahepatic lymphatic invasion, especially in combination with vascular invasion, is an important adverse prognostic factor for overall survival in patients with solitary CRLM after liver resection.

Variation in hospital treatment patterns for metastatic colorectal cancer

BACKGROUND

There are many treatment options for metastatic colorectal cancer (CRC). However, to the authors' knowledge, national treatment patterns for metastatic CRC, and the stability of hospital treatment patterns over time, have not been well described.

METHODS

Data from the 2006 through 2011 National Cancer Data Base were used to study adults with newly diagnosed metastatic CRC (84,161 patients from 1051 hospitals). Using hierarchical models, the authors characterized hospital volume in the use of different treatment modalities (primary site resection, metastatic site resection, chemotherapy, and palliative care). The authors then assessed variation in the receipt of treatment according to the hospitals' relative volume of services used. Finally, the extent to which hospital treatment patterns changed over the past decade was examined.

RESULTS

Overall use of volume of services varied widely (5.0% in the hospitals with low volumes of service to 22.3% in the hospitals with high volumes of service). As hospitals' volumes of services increased, adjusted rates of metastatic site surgery (6.6% to 30.8%; P<.001) and multiagent chemotherapy (37.8% to 57.4%; P<.001) use increased, but primary site resection demonstrated little variation (56.8% vs 59.5%; P = .024). It is interesting to note that use of palliative care also increased (8.1% to 11.3%; P = .002). Hospital treatment patterns did not change over time, with hospitals with high volumes of service consistently using more metastatic site resection and multiagent chemotherapy than hospitals with low volumes of service.

CONCLUSIONS

There is wide variation in hospital treatment patterns for patients with metastatic CRC, and these patterns have been stable over time. It appears that much of the approach for metastatic CRC treatment depends on the hospital in which the patient presents.

Surgical Referral for Colorectal Liver Metastases: A Population-Based Survey

BACKGROUND

Surgical resection is underutilized for patients with colorectal liver metastases (CLM). Although the causes of underutilization are poorly understood, provider attitudes towards surgical referral may be contributory. We sought to understand medical oncologists' perspectives on referral for CLM.

METHODS

Medical oncologists who treat colorectal cancer in the US state of Michigan were surveyed. We characterized respondents' attitudes regarding clinical and tumor-related contraindications to liver resection for CLM, as well as referral and treatment preferences using case-based scenarios. We then evaluated practice characteristics and treatment preferences between physicians.

RESULTS

A total of 112 eligible responses were received (46 % response rate). Nearly 40 % of respondents reported having no liver surgeons in their practice area. Commonly perceived contraindications to liver resection included extrahepatic disease (80.3 %), poor performance status (77.7 %), the presence of >4 metastases (62.5 %), bilobar metastases (43.8 %), and metastasis size >5 cm (40.2 %). Compared with high-referring physicians, low-referring physicians were just as likely to refer a patient with very low recurrence risk (89.3 vs. 98.3 %; p = 0.099), but much less likely to refer a patient with moderate risk (0 vs. 82.8 %; p < 0.001). High-referring physicians were more likely to consider resection for scenarios consistent with higher recurrence risk (31.0 vs. 10.7 %; p = 0.05).

CONCLUSIONS

We found wide variation in surgical referral patterns for CLM. Many felt that bilobar disease and tumor size were contraindications to liver-directed therapy despite a lack of supporting data. These findings suggest an urgent need to increase dissemination of evidence and guidance regarding management for CLM, perhaps through increased specialist participation in tumor boards.

Discrete choice experiments in health economics: a review of the literature

BACKGROUND

Discrete choice experiments (DCEs) are increasingly used in health economics to address a wide range of health policy-related concerns.

OBJECTIVE

Broadly adopting the methodology of an earlier systematic review of health-related DCEs, which covered the period 2001-2008, we report whether earlier trends continued during 2009-2012.

METHODS

This paper systematically reviews health-related DCEs published between 2009 and 2012, using the same database as the earlier published review (PubMed) to obtain citations, and the same range of search terms.

RESULTS

A total of 179 health-related DCEs for 2009-2012 met the inclusion criteria for the review. We found a continuing trend towards conducting DCEs across a broader range of countries. However, the trend towards including fewer attributes was reversed, whilst the trend towards interview-based DCEs reversed because of increased computer administration. The trend towards using more flexible econometric models, including mixed logit and latent class, has also continued. Reporting of monetary values has fallen compared with earlier periods, but the proportion of studies estimating trade-offs between health outcomes and experience factors, or valuing outcomes in terms of utility scores, has increased, although use of odds ratios and probabilities has declined. The reassuring trend towards the use of more flexible and appropriate DCE designs and econometric methods has been reinforced by the increased use of qualitative methods to inform DCE processes and results. However, qualitative research methods are being used less often to inform attribute selection, which may make DCEs more susceptible to omitted variable bias if the decision framework is not known prior to the research project.

CONCLUSIONS

The use of DCEs in healthcare continues to grow dramatically, as does the scope of applications across an expanding range of countries. There is increasing evidence that more sophisticated approaches to DCE design and analytical techniques are improving the quality of final outputs. That said, recent evidence that the use of qualitative methods to inform attribute selection has declined is of concern.

Imaging in resectable colorectal liver metastasis patients with or without preoperative chemotherapy: results of the PROMETEO-01 study

Background:

The aim of the PROMETEO-01 Study was to define the diagnostic accuracy of imaging techniques in colorectal cancer liver metastasis (CRCLM) patients.

Methods:

Patients referred to Bologna S. Orsola-Malpighi Hospital performed a computed-tomography scan (CT), magnetic resonance (MR), 18F-FDG-PET/CTscan (PET/CT) and liver contrast-enhanced-ultrasound (CEUS); CEUS was also performed intraoperatively (i-CEUS). Every pathological lesion was compared with imaging data.

Results:

From December 2007 to August 2010, 84 patients were enrolled. A total of 51 (60.71%) resected patients were eligible for analysis. In the lesion-by-lesion analysis 175 resected lesions were evaluated: 67(38.3%) belonged to upfront resected patients (group-A) and 108 (61.7%) to chemotherapy-pretreated patients (group-B). In all patients the sensitivity of MR proved better than CT (91% vs 82% P=0.002), CEUS (91 vs 81% P=0.008) and PET/CT (91% vs 60% P=0.000), whereas PET/CT showed the lowest sensitivity. In group-A the sensitivity of i-CEUS, MR, CT, CEUS and PET/CT was 98%, 94%, 91%, 84% and 78%, respectively. In group-B the i-CEUS proved equivalent in sensitivity to MR (95% and 90%, respectively, P=0.227) and both were significantly more sensitive than other procedures. The CT sensitivity in group-B was lower than in group-A (77% vs 91%, P=0.024).

Conclusions:

A thoraco-abdominal CT provides an adequate baseline evaluation and guides judgment as to the resectability of CRCLM patients. In the subset of candidates for induction chemotherapy to increase the chance of liver resection, the most rational approach is to add MR for the staging and restaging of CRCLM.

Percutaneous radiofrequency ablation (RFA) or robotic radiosurgery (RRS) for salvage treatment of colorectal liver metastases

BACKGROUND

Stereotactic radiation therapy is an evolving modality to treat otherwise unresectable liver metastases. In this analysis, two local therapies: 1) single session robotic radiosurgery (RRS) and 2) percutaneous radiofrequency ablation (RFA) were compared in a total of 60 heavily pretreated colorectal cancer patients.

METHODS

Thirty patients with a total of 35 colorectal liver metastases not qualifying for surgery that were treated in curative intent with RRS were prospectively followed. To compare efficacy of both treatment modalities, patients treated with RFA during the same period of time were matched according to number and size of the treated lesions. Local tumor control, local disease free survival (DFS), and freedom from distant recurrence (FFDR) were analyzed for efficacy. Treatment-related side effects were recorded for comparison.

RESULTS

The median diameter of the treated lesions was 33 mm (7-53 mm). Baseline characteristics did not differ significantly between the groups. One- and two-year local control rates showed no significant difference but favored RRS (85% vs. 65% and 80% vs. 61%, respectively). A significantly longer local DFS of patients treated with RRS compared to RFA (34.4 months vs. 6.0 months; p < 0.001) was found. Both, median FFDR (11.4 months for RRS vs. 7.1 months for RFA p = 0.25) and the recurrence rate (67% for RRS and 63% for RFA, p > 0.99) were comparable.

CONCLUSION

Single session RRS is a safe and effective method to treat colorectal liver metastases. In this analysis, a trend towards longer DFS was seen in patients treated with RRS when compared to RFA.

VEGF levels and the angiogenic potential of the microenvironment can affect surgical strategy for colorectal liver metastasis

The hypotheses emerging from basic research on colorectal liver metastases must be tested in clinical situations for the adaptation of current treatment strategies. Pre-metastatic niches have been shown to exist in human colorectal synchronous metastases, with the liver parenchyma adjacent to the synchronous liver metastases providing a favorable, angiogenic environment for metastatic tumor growth. The role of the VEGF signaling pathway in liver regeneration and tumor growth remains unclear, but the use of antiangiogenic agents in combination with surgical treatment is almost certainly beneficial.