Whole body magnetic resonance in indolent lymphomas under watchful waiting: The time is now

Abstract

The indolent non-Hodgkin lymphomas (i-NHLs) are characterised by 'indolent' clinical behaviour with slow growth and prolonged natural history. The watchful waiting (WW) strategy is a frequently employed treatment option in these patients. This implies a strict monitoring by imaging examinations, including 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG-PET/CT) and CT. A major concern is radiation exposure due to regularly monitoring by conventional imaging procedures. Several studies have demonstrated the reliability of whole-body magnetic resonance imaging (WB-MRI) for lymphoma staging. WB-MRI could be useful for active surveillance in iNHLs providing the suspect of disease progression that can be then confirmed by additional diagnostic procedures, including 18F-FDG-PET/CT. The directive 2013/59 by the European Union claims that if a radiation-free imaging technique allows obtaining the same diagnostic results, it should be invariably used.In this setting, WB-MRI may be considered a reasonable option in i-NHLs under WW, replacing imaging modalities that cause exposure to ionising radiations. This will help to reduce the cancer risk in i-NHL patients for whom chemo-/radiotherapy remain the usual treatment options following the usually long WW phase. The scientific community should raise the awareness of the risk of ionising radiations in i-NHLs and the emphasise the need for establishing the proper place of WB-MRI in lymphoma imaging. Key Points• Watchful waiting is a reasonable option in patients with indolent non-Hodgkin lymphomas.• Imaging is crucial to monitor patients with indolent nonHodgkin lymphomas.• CT and 18 F-FDG-PET/CT are commonly used, implying a substantial radiation exposure.• WB-MRI is highly reliable in lymphoma staging.• WB-MRI may be considered to monitor indolent nonHodgkin lymphomas under watchful waiting.

Diagnostic accuracy of diffusion‐weighted imaging‐ magnetic resonance imaging compared to positron emission tomography/computed tomography in evaluating and assessing pathological response to treatment in adult patients with lymphoma: A systematic review

“…38 MRI has been shown to be of benefit in assessing local disease and recurrent disease in other malignancy, but PET/CT may have advantages in assessing diffuse or distant disease. The heterogenicity of the lymphoma subtypes, many of which have different clinical courses, 40 as well as the varying protocols for DW-MRI also makes interpretation of the result more challenging. Firstly, we excluded studies in which paediatric patients were included.…”

“…However, the exclusion of this group reduced the overall power of the study. The heterogenicity of the lymphoma subtypes, many of which have different clinical courses, 40 as well as the varying protocols for DW-MRI also makes interpretation of the result more challenging.…”

MRI and PET/MRI in hematologic malignancies

“…However, while it is generally recognized that ADCs reflect treatment response per se, no ADC cutoff values are presently established for separating partial from complete response, which is of high clinical significance, and there is also no MRI‐based scoring system comparable to the Deauville score (ie, no reference tissue definitions). Therefore, since [ 18 F]FDG‐PET/CT is currently so well established as the imaging technique of choice for response assessment, WB‐MRI may need to establish its role in clinical situations where PET/CT is currently not recommended in clinical routine, such as in the monitoring of lymphoma patients who have achieved complete remission, or in patients with indolent NHL subtypes that undergo "watchful waiting"—a recent publication showed that WB‐MRI seems to be well suited for this task …”

Renal endometriosis mimicking complicated cysts of kidney: report of two cases

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