Resectability and Ablatability Criteria for the Treatment of Liver Only Colorectal Metastases:Multidisciplinary Consensus Document from the COLLISION Trial Group

The guidelines for metastatic colorectal cancer crudely state that the best local treatment should be selected from a 'toolbox' of techniques according to patient- and treatment-related factors. We created an interdisciplinary, consensus-based algorithm with specific resectability and ablatability criteria for the treatment of colorectal liver metastases (CRLM). To pursue consensus, members of the multidisciplinary COLLISION and COLDFIRE trial expert panel employed the RAND appropriateness method (RAM). Statements regarding patient, disease, tumor and treatment characteristics were categorized as appropriate, equipoise or inappropriate. Patients with ECOG≤2, ASA≤3 and Charlson comorbidity index ≤8 should be considered fit for curative-intent local therapy. When easily resectable and/or ablatable (stage IVa), (neo)adjuvant systemic therapy is not indicated. When requiring major hepatectomy (stage IVb), neo-adjuvant systemic therapy is appropriate for early metachronous disease and to reduce procedural risk. To downstage patients (stage IVc), downsizing induction systemic therapy and/or future remnant augmentation is advised. Disease can only be deemed permanently unsuitable for local therapy if downstaging failed (stage IVd). Liver resection remains the gold standard. Thermal ablation is reserved for unresectable CRLM, deep-seated resectable CRLM and can be considered when patients are in poor health. Irreversible electroporation and stereotactic body radiotherapy can be considered for unresectable perihilar and perivascular CRLM 0-5cm. This consensus document provides per-patient and per-tumor resectability and ablatability criteria for the treatment of CRLM. These criteria are intended to aid tumor board discussions, improve consistency when designing prospective trials and advance intersociety communications. Areas where consensus is lacking warrant future comparative studies.</p

Colorectal liver metastases: Surgery versus thermal ablation (COLLISION) - a phase III single-blind prospective randomized controlled trial

Background: Radiofrequency ablation (RFA) and microwave ablation (MWA) are widely accepted techniques to eliminate small unresectable colorectal liver metastases (CRLM). Although previous studies labelled thermal ablation inferior to surgical resection, the apparent selection bias when comparing patients with unresectable disease to surgical candidates, the superior safety profile, and the competitive overall survival results for the more recent reports mandate the setup of a randomized controlled trial. The objective of the COLLISION trial is to prove non-inferiority of thermal ablation compared to hepatic resection in patients with at least one resectable and ablatable CRLM and no extrahepatic disease. Methods: In this two-arm, single-blind multi-center phase-III clinical trial, six hundred and eighteen patients with at least one CRLM (≤3cm) will be included to undergo either surgical resection or thermal ablation of appointed target lesion(s) (≤3cm). Primary endpoint is OS (overall survival, intention-to-treat analysis). Main secondary endpoints are overall disease-free survival (DFS), time to progression (TTP), time to local progression (TTLP), primary and assisted technique efficacy (PTE, ATE), procedural morbidity and mortality, length of hospital stay, assessment of pain and quality of life (QoL), cost-effectiveness ratio (ICER) and quality-adjusted life years (QALY). Discussion: If thermal ablation proves to be non-inferior in treating lesions ≤3cm, a switch in treatment-method may lead to a reduction of the post-procedural morbidity and mortality, length of hospital stay and incremental costs without compromising oncological outcome for patients with CRLM. Trial registration:NCT03088150 , January 11th 2017

Metric Semantics and Full Abstractness for Action Refinement and Probabilistic Choice

This paper provides a case-study in the field of metric semantics for probabilistic programming. Both an operational and a denotational semantics are presented for an abstract process language L_pr, which features action refinement and probabilistic choice. The two models are constructed in the setting of complete ultrametric spaces, here based on probability measures of compact support over sequences of actions. It is shown that the standard toolkit for metric semantics works well in the probabilistic context of L_pr, e.g. in establishing the correctness of the denotational semantics with respect to the operational one. In addition, it is shown how the method of proving full abstraction --as proposed recently by the authors for a nondeterministic language with action refinement-- can be adapted to deal with the probabilistic language L_pr as well

Drug coated balloon supported Supera stent versus Supera stent in intermediate and long-segment lesions of the superficial femoral artery:2-year results of the RAPID Trial

BACKGROUND: Endovascular treatment of occlusive disease of the superficial femoral artery (SFA) has evolved from plain old balloon angioplasty (MBA) through primary stenting strategy to drug eluting technology-based approach. The RAPID Trial investigates the added value of drug coated balloons (DCB, Legflow) in a primary stenting strategy (Supera stent) for intermediate (5-15 cm) and long segment (&gt;15 cm) SFA lesions.METHODS: In this multicenter, patient-blinded trial, 160 patients with intermittent claudication, ischemic rest pain, or tissue loss due to intermediate or long SFA lesions were randomized (1:1) between Supera + DCB and Supera. Primary endpoint was primary patency at 2 years, defined as freedom from restenosis on duplex ultrasound (peak systolic velocity ratioRESULTS: At 2 years, primary patency was 55.1% (95% CI: 43.1-67.1%) in the Supera + DCB group versus 48.3% (95% CI: 35.6-61.0%) in the Supera group (P=0.957). Per protocol analysis showed a primary patency rate of 60.9% (95% CI: 48.6-73.2%) in the Supera + DCB group versus 49.8% (95% CI: 36.9-62.7%) in the Supera group (P=0.469). The overall mortality rate was 5% in both groups (P=0.975). Sustained functional improvement was similar in both groups.CONCLUSIONS: The 2-year results in the current trial of a primary Supera stenting strategy are consistent with other trials reporting on treatment of intermediate and long SFA lesions. A DCB supported Supera stent strategy did not improve patency rate compared to a Supera stent only strategy.</p