We present four cases of intravascular large B-cell lymphoma (IVLBCL), a rare malignancy with poor outcomes. The exclusive presence of lymphoma cells in blood vessels leads to a heterogenous presentation and poor diagnostic yield with traditional initial diagnostic tools. Timely diagnosis and treatment can lead to improved outcomes.

We report a rare case of monoclonal gammopathy of renal significance with immunotactoid glomerulopathy and severe nephrotic syndrome. The patient was diagnosed with a B-cell IgM κ clone and her nephrotic syndrome is responding well to bortezomib, dexamethasone, and rituximab.