Iacovelli et al. explore the importance of tumour burden as a prognostic factor in metastatic RCC (mRCC). Although intuitively obvious, it has rarely been shown that the more extensively metastatic a patient's disease, the more negative is his/her prognosis. Indeed, there is probably more information to be extracted from tumour size and burden than has been done up until now.

With the chronicization of mRCC through the development of multiple therapeutic drugs, different profiles of patients are emerging. Some patients progress rapidly despite therapy, others are stable for a long time without treatment [1]. It is also being discussed whether to treat asymptomatic patients at all. Nevertheless, we lack the ability to predict to which category each patient will belong, and tumour burden might be one of the factors influencing their outcome, although the present study does not correlate tumour burden to response to therapy.

Overall, measuring tumours remains the simplest way to estimate the severity of disease and predict response or, conversely, progression. Despite extensive literature on the potential of functional imaging [2–4], only tumour size is universally applicable and reliable [5,6]. The focus must be on finding clinically relevant criteria, which will help guide the oncologist in terms of therapeutic choices. Thus, collaboration must continue between oncologists and radiologists, to better understand when and how patients should be treated, or when they would not benefit from further therapy.


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  • 1
    Rini BI, Flaherty K. Clinical effect and future considerations for molecularly-targeted therapy in renal cell carcinoma. Urol Oncol 2008; 26: 5439
  • 2
    Fournier LS, Oudard S, Thiam R et al. Metastatic renal carcinoma: evaluation of antiangiogenic therapy with dynamic contrast-enhanced CT. Radiology 2010; 256: 5118
  • 3
    Harry VN, Semple SI, Parkin DE, Gilbert FJ. Use of new imaging techniques to predict tumour response to therapy. Lancet Oncol 2010; 11: 92102
  • 4
    Lassau N, Koscielny S, Albiges L et al. Metastatic renal cell carcinoma treated with sunitinib: early evaluation of treatment response using dynamic contrast-enhanced ultrasonography. Clin Cancer Res 2010; 16: 121625
  • 5
    Krajewski KM, Guo M, Van den Abbeele AD et al. Comparison of four early posttherapy imaging changes (EPTIC; RECIST 1.0, tumor shrinkage, computed tomography tumor density, Choi criteria) in assessing outcome to vascular endothelial growth factor-targeted therapy in patients with advanced renal cell carcinoma. Eur Urol 2011; 59: 85662
  • 6
    Thiam R, Fournier LS, Trinquart L et al. Optimizing the size variation threshold for the CT evaluation of response in metastatic renal cell carcinoma treated with sunitinib. Ann Oncol 2010; 21: 93641