No abstract

In the past decade active surveillance (AS) of men with localized prostate cancer has become an increasingly popular management option, and a range of clinical guidelines have been published on this topic. Existing guidelines regarding AS for prostate cancer vary widely, but predominantly state that the most suitable patients for AS are those with pretreatment clinical stage T1c or T2 tumours, serum PSA levels <10 ng/ml, biopsy Gleason scores of 6 or less, a maximum of one or two tumour-positive biopsy core samples and/or a maximum of 50% of cancer per core sample. Following initiation of an AS programme, most guidelines recommend serial serum PSA measurements, digital rectal examinations and surveillance biopsies to check for and identify pathological indications of tumour progression. Definitions of disease reclassification and progression differ among guidelines and multiple criteria for initiation of definitive treatment are proposed. The variety of descriptions of criteria for clinically insignificant prostate cancer indicates a lack of consensus on optimal AS and intervention thresholds. A single set of guidelines are needed in order to reduce variations in clinical practice and to optimize clinical decision-making. To enable truly evidence-based guidelines, further research that combines existing evidence, while also gathering information from more long-term studies is needed.

Minimally invasive interventional therapies are evolving rapidly and their use for the treatment of solid tumours is becoming more extensive. The in situ destruction of solid tumours by such therapies is thought to release antigens that can prime an antitumour immune response. In this review, we offer an overview of the current evidence for immune response activation associated with the utilisation of the main thermal and non-thermal ablation therapies currently in use today. This is followed by an assessment of the hypothesised mechanisms behind this immune response priming and by a discussion of potential methods of harnessing this specific response, which may subsequently be applicable in the treatment of cancer patients. References were identified through searches of PubMed/MEDLINE and Cochrane databases to identify peer-reviewed original articles, meta-analyses and reviews. Papers were searched from 1850 until October 2014. Articles were also identified through searches of the authors' files. Only papers published in English were reviewed. Thermal and non-thermal therapies have the potential to stimulate antitumour immunity although the current body of evidence is based mostly on murine trials or small-scale phase 1 human trials. The evidence for this immune-modulatory response is currently the strongest in relation to cryotherapy and radiotherapy, although data is accumulating for related ablative treatments such as high-intensity focused ultrasound, radiofrequency ablation and irreversible electroporation. This effect may be greatly enhanced by combining these therapies with other immunostimulatory interventions. Evidence is emerging into the immunomodulatory effect associated with thermal and non-thermal ablative therapies used in cancer treatment in addition to the mechanism behind this effect and how it may be harnessed for therapeutic use. A potential exists for treatment approaches that combine ablation of the primary tumour with control and possible eradication of persistent, locally recurrent and metastatic disease. However, more work is needed into each of these modalities, initially in further animal studies and then subsequently in large-scale prospective human studies.

Michele Scialpi, et al.; Biparametric magnetic resonance imaging in the surveillance of testicular tumors following radical orchiectomy.