A comprehensive approach to assess the existing evidence and appropriateness of anticancer drugs on advanced cancer: the ASTAC project

Article type
Bracchiglione J1, Santero M2, Salazar J2, Rodríguez-Grijalva G2, Requeijo C2, Meade AG2, Selva A3, Savall O2, Merchan A2, Cantero Y2, Hernández E2, Meza N4, Acosta-Dighero R4, Quintana MJ2, Bonfill X1
1Iberoamerican Cochrane Centre, IIB Sant Pau, CIBERESP, UAB, Barcelona
2Iberoamerican Cochrane Centre IIB Sant Pau, Barcelona
3Clinical Epidemiology and Cancer Screening, Parc Taulí Hospital Universitari. Institut d’Investigació i Innovació Parc Taulí (I3PT_CERCA), Sabadell
4Interdisciplinary Centre for Health Studies (CIESAL), Universidad de Valparaíso, Viña del Mar
Background: Appropriateness of Systemic Treatments for Advanced Cancers (ASTAC) is a collaborative research project aiming to assess the appropriateness of anticancer drugs in advanced digestive non-intestinal cancers (ADNIC), contributing to reduce potential scenarios of misuse.

Objective: To describe the ASTAC approach for broad evidence synthesis.

Methods: We synthesised evidence on efficacy and safety through overviews, evidence gap maps (EGMs) and systematic reviews (SRs), according to the following steps:

1) We searched in MEDLINE, EMBASE, Cochrane, Epistemonikos and PROSPERO for SRs, randomised controlled trials (RCTs) and observational studies regarding our research questions.

2) We classified the identified SRs according to cancer location, and conducted three overviews. These overviews included all relevant SRs. We created matrices of evidence and de novo meta-analyses.

3) For conducting the EGMs, we used all the previously identified SRs (plus the RCT and observational studies already identified), and we ran a new and broader search strategy. We re-started the screening process, complementing the search with clinicaltrials.gov.

4) Once we had all the SRs, RCTs and observational studies identified, we conducted three EGMs. The EGMs informed which new SRs were more appropriate to conduct.

5) We used the RCTs included in the EGMs for the new SRs. At this stage, we also conducted a forward citation search to retrieve newer studies.

6) We conducted data extraction and analysis for the SRs, comparing our assessments with those made by authors of other SRs (identified by previous overviews).

In parallel, we conducted a multicenter retrospective cohort study to describe ADNIC patients’ treatments, for judging the appropriateness of these interventions.

Results: The project is in its final stage. At the moment of this submission, we have published three overviews and one EGM, and submitted other two EGMs. We are in the final phase of five SRs. In parallel, we are finishing data analysis for the cohort study.

Conclusions: ASTAC has managed to combine optimally different methodological approaches for synthesising evidence, contrasting them with current clinical practice. Evidence to treat ADNICs with anticancer drugs is sparse and, in consequence, treatments could be often considered inappropriate.

Patient, public and/or healthcare consumer involvement: None