Oncological imaging: tumor surveillance in children

Abstract

As the need for accurate diagnostic imaging often continues throughout a cancer survivor’s life, imaging methods with the least toxicity must be used so as to provide needed information without contributing to long-term sequelae that might compound toxicities inherent with the primary disease and its treatment. In this regard, the costs, benefits and potential risks of post-therapy monitoring for disease recurrence warrant periodic review. Unfortunately, few analyses are available regarding the impact of surveillance imaging on the detection of disease recurrence, salvage rates of relapse disease and long-term survival outcomes for pediatric cancer survivors. This review will examine the role and limitations of surveillance imaging in pediatric oncology.

Surveillance imaging and radiation exposure in the detection of relapsed neuroblastoma

“…We also found that in addition to history/symptoms and UCats, MIBG scans detected the majority of recurrences. However, our study and several other reports of surveillance imaging for non‐NB pediatric cancers have not shown that early detection is associated with improved salvage rates or survival . Further support to decrease the use of CT specifically for pulmonary metastatic disease at recurrence was recently demonstrated in another single institution study.…”

“…It is also more user‐dependent, with greater variability in experience between imaging centers. Finally, for the majority of pediatric cancers, including NB, there is no evidence that early detection of recurrence on surveillance imaging is associated with improved salvage rates or impacts overall survival …”

Is routine pelvic surveillance imaging necessary in patients with Wilms tumor?

“…Because approximately 90% of children with Wilms tumor can be cured with contemporary therapy13 and a significant proportion of those who relapse can be salvaged,12‐14 the utility of routine, off‐therapy surveillance imaging is controversial 3‐6, 23. It is also unclear whether the use of imaging to detect clinically asymptomatic disease recurrence in the abdomen and pelvis has an impact on salvage rates or patient outcomes.…”

CT radiation dose reduction: can we do harm by doing good?

“…In September 2011, Pediatric Radiology published a supplement containing the contents of a recent ALARA conference [1][2][3][4][5][6][7][8][9][10]. One month later, Radiology published an editorial titled "CT radiation dose: trending in the right direction" [11].…”

“…Better methods for estimating actual patient dose are being suggested, as the limitations of indices such as CTDI and DLP are being taught [1,3,5,6]. Population dose is being decreased with reduction of inappropriate studies and formulation of appropriateness criteria [1,4,7,9,10]. Further dose reductions occur from optimizing CT techniques [1,4,7,8].…”