Report of an International Workshop to Standardize Baseline Evaluation and Response Criteria for Primary CNS Lymphoma

Abstract

Standardized guidelines for the baseline evaluation and response assessment of primary CNS lymphoma (PCNSL) are critical to ensure comparability among clinical trials for newly diagnosed patients. The relative rarity of this tumor precludes rapid completion of large-scale phase III trials and, therefore, our reliance on the results of well-designed phase II trials is critical. To formulate this recommendation, an international group of experts representing hematologic oncology, medical oncology, neuro-oncology, neurology, radiation oncology, neurosurgery, and ophthalmology met to review current standards of reporting and to formulate a consensus opinion regarding minimum baseline evaluation and common standards for assessing response to therapy. The response guidelines were based on the results of neuroimaging, corticosteroid use, ophthalmologic examination, and CSF cytology. A critical issue that requires additional study is the optimal method to assess the neurocognitive impact of therapy and address the quality of life of PCNSL survivors. We hope that these guidelines will improve communication among investigators and comparability among clinical trials in a way that will allow us to develop better therapies for patients.

Patterns of response and relapse in primary CNS lymphomas after first-line chemotherapy: imaging analysis of the ANOCEF-GOELAMS prospective randomized trial

“…The response rates were analyzed using the IPCG criteria. 6 These response criteria define complete response (CR) as complete disappearance of contrast enhancement on MRI, no evidence of ocular lymphoma, negative CSF cytology, and discontinuation of corticosteroid use for at least 2 weeks prior to the evaluation of response. Unconfirmed CR (Cru) is used to characterize radiographic findings that fulfill criteria for a CR, but the patient remains on corticosteroids, or MRI that continues to show small but persistent enhancing abnormalities possibly related to biopsy or surgery.…”

“…The most commonly used response criteria are those published by the International PCNSL Collaborative Group (IPCG), which combines MRI findings, eye examination, cerebrospinal fluid (CSF) analysis, and steroid dose. 6 Of note, MRI response criteria rely on contrast enhancement measure changes and does not take into consideration non-enhancing lesions typically visualized on T2 fluid attenuated inversion recovery (FLAIR) MRI. Finally, neuroimaging features at relapse are poorly documented.…”

Systemic high-dose methotrexate plus ifosfamide is highly effective for central nervous system (CNS) involvement of lymphoma

“…In patients treated after August 2005, response of parenchymal lesions was evaluated according to the then published criteria of the International Primary CNS Lymphoma Collaborative Group (IPCG) [13]. Those included the specification of an unconfirmed complete remission (CRu) for cases with small but persisting enhancing abnormalities on brain imaging or patients fulfilling the criteria for complete remission (CR) but still receiving corticosteroids.…”

Primary central nervous system lymphoma: what a neurologist/neurosurgeon should know?

“…When this is the main hypothesis, and if patients are stable with no life-threatening edema, the use of corticosteroids should be limited. The use of corticosteroids may impair the acquirement of material and can even interfere in histopathologic diagnosis 13 . If patients are already on steroids, the interruption of therapy 7-10 days before biopsy should be considered in order to improve diagnosis, unless a MRI-confirmed progression on steroids is observed.…”