Primary central nervous system lymphomas (PCNSL): MRI response criteria revised

Area of Science:

• Neuro-oncology
• Radiology
• Clinical trial methodology

Background:

• Primary CNS lymphoma (PCNSL) diagnosis and treatment response assessment are challenging.
• Current response criteria, like the Macdonald criteria, rely on imaging features such as contrast enhancement.
• The interpretation of residual contrast enhancement in PCNSL requires careful consideration.

Purpose of the Study:

• To evaluate the applicability of the Macdonald response criteria in patients with PCNSL.
• To determine if persisting contrast-enhancing lesions after primary therapy accurately predict tumor progression in PCNSL.
• To propose a modification to the Macdonald criteria based on observed outcomes.

Main Methods:

• Retrospective analysis of 68 patients with PCNSL.
• Assessment of contrast-enhancing lesions after primary therapy using imaging.
• Correlation of imaging findings with clinical outcomes, including tumor progression and survival.

Main Results:

• Four out of 68 patients with persistent contrast-enhancing lesions did not receive further treatment.
• None of these patients showed evidence of tumor progression during follow-up periods of up to 54 months.
• This suggests that contrast enhancement alone may not reliably indicate active lymphoma.

Conclusions:

• The Macdonald response criteria may require modification for PCNSL to avoid overestimating treatment response.
• Persistent contrast enhancement after primary therapy in PCNSL might not always signify residual disease.
• Further research and validation are needed for refined response assessment in PCNSL.