Presurgical Identification of Primary Central Nervous System Lymphoma with Normalized Time-Intensity Curve: A Pilot Study of a New Method to Analyze DSC-PWI

Normalized mean tumor curves for each type (PCNSL, glioblastoma, anaplastic astrocytoma, metastasis, and meningioma) obtained in the training subset (A). The curves are superimposable and comparable in a single graphic. This format provides a user-friendly tool for visual comparison of curves. Paired comparisons of normalized mean tumor curves for PCNSL against glioblastoma (B), anaplastic astrocytoma (C), metastasis (D), and meningioma (E), as well as representation of the 5 stepwise selected discriminatory TTP-TTA time points per pair (black dots).

Example of clinical applicability on a “real” problem case. Axial CE-T1WI of 2 different patients (A and D) depicting 2 subcortical right frontal, solid enhancing tumors. PCNSL and anaplastic astrocytoma may be diagnostic possibilities to consider. Tumor normalized curves of each case overlapped to PCNSL, and anaplastic astrocytoma mean curves for visual assessment (B and E) show that the case in the upper row has similarities with PCNSL while in contrast, the case in the lower row has similarities with anaplastic astrocytoma. Representation of the classifier results on a scatterplot (C and F) demonstrates that the case in the upper row remains on the inferior side and may likely be a PCNSL, while the case in the lower row is more likely to be an anaplastic astrocytoma. We pathologically confirmed both diagnoses: case in the upper row, PCNSL; case in the lower row, anaplastic astrocytoma.