title: The oligometastatic state - separating truth from wishful thinking.
abstract: The oligometastatic paradigm implies that patients who develop a small number of metastatic lesions might achieve long-term survival if all these lesions are ablated with surgery or stereotactic radiotherapy. Clinical data indicate that the number of patients with oligometastatic disease receiving aggressive treatment is increasing rapidly. We examine the key evidence supporting or refuting the existence of an oligometastatic state. Numerous single-arm studies suggest that long-term survival is 'better-than-expected' after ablative treatment. However, the few studies with adequate controls raise the possibility that this long-term survival might not be due to the treatments themselves, but rather to the selection of patients based on favourable inclusion criteria. Furthermore, ablative treatments carry a risk of harming healthy tissue, yet the risk-benefit ratio cannot be quantified if the benefits are unmeasured. If the strategy of treating oligometastases is to gain widespread acceptance as routine clinical practice, there should be stronger evidence supporting its efficacy.
authors: Division of Radiation Oncology, London Health Sciences Centre, 790 Commissioners Road East, London, ON N6A 4L6, Canada.
authors: David A
authors: DA
authors: Palma
authors: Department of Radiation Oncology, Duke University School of Medicine, 508 Fulton Street, Durham, NC 27705, USA.
authors: Joseph K
authors: JK
authors: Salama
authors: Department of Radiation Oncology, University Hospitals Seidman Cancer Center, Case Comprehensive Cancer Center, 11100 Euclid Avenue, Cleveland, OH 44106, USA.
authors: Simon S
authors: SS
authors: Lo
authors: Department of Radiation Oncology, VU University Medical Centre, De Boelelaan 1117, PO Box 7057, Amsterdam, 1007 MB, Netherlands.
authors: Suresh
authors: S
authors: Senan
authors: Clinical Operational Research Unit, University College London, 4 Taviton Street, London WC1H 0BT, UK.
authors: Tom
authors: T
authors: Treasure
authors: Washington University School of Medicine, 660 South Euclid Avenue, St Louis, MO 63110, USA.
authors: Ramaswamy
authors: R
authors: Govindan
authors: University of Chicago Medical Center, 5841 South Maryland Avenue, Chicago, IL 60637, USA.
authors: Ralph
authors: R
authors: Weichselbaum
mesh_terms: D000970:Antineoplastic Agents / Q000627:therapeutic use; D017115:Catheter Ablation; D006801:Humans; D008954:Models, Biological; D009362:Neoplasm Metastasis / Q000473:pathology* / Q000628:therapy*; D061206:Neoplasm Micrometastasis; D009369:Neoplasms / Q000473:pathology* / Q000601:surgery*; D018579:Patient Selection; D016634:Radiosurgery; D016032:Randomized Controlled Trials as Topic; D015996:Survival Rate; D047368:Tumor Burden
chemical_list: D000970:Antineoplastic Agents