Limited efficacy of high-dose methotrexate in patients with neurolymphomatosis

Recurrence of diffuse large B-cell lymphoma in sciatic and tibial nerves: A case report

Infiltration of peripheral or cranial nerves with lymphatic cells is a rare condition that is known as neurolymphomatosis (NL). The involvement could be primary or secondary and mostly occurs in patients with a history of B-cell lymphoma. The most common peripheral nerve involved is the sciatic nerve. Patients may present with painful or painless mononeuropathy or polyneuropathy, and MRI is the perfect modality to evaluate the suspicious clinical findings that may demonstrate enlargement, thickening, and enhancement of the involved nerve or an enhancing mass lesion in the course of the nerve. Biopsy can be safely performed to confirm the diagnosis. Few articles have reported the cases of peripheral nerve involvement by lymphoma as well as MRI features of this diagnosis. In this article, we report a case of NL using MRI, ultrasound, and pathologic features and also present a brief review of relevant literature.

Thiotepa-based high-dose chemotherapy with autologous stem cell transplantation for neurolymphomatosis

Neurolymphomatosis (NL) is a rare clinical entity characterized by lymphomatous infiltration of the peripheral nervous system. According to recent retrospective data, consolidative high-dose chemotherapy (HDC) with autologous stem cell transplantation (ASCT) may be beneficial for NL. However, few reports to date have discussed optimal conditioning regimens. Herein, we report two cases of NL in patients with relapsed intravascular large B-cell lymphoma who received consolidative thiotepa-containing HDC-ASCT. Case 1: A 56-year-old woman who relapsed 2 months after the first complete remission (CR) and underwent ASCT. Case 2: A 65-year-old woman who relapsed 8 months after the first CR and underwent ASCT. Both patients engrafted. Time to neutrophil engraftment was 10 and 12 days after HDC-ASCT, and CR was sustained for 26 and 18 months, respectively, as of the last follow-up. Although there is little evidence supporting the utility of thiotepa-based HDC-ASCT in patients with NL, the results of this case report suggest that further studies are warranted to determine its efficacy in this setting.

Limited efficacy of high-dose methotrexate to prevent the central nervous system relapse in patients with IVLBCL

To evaluate the efficacy of high-dose methotrexate (HD-MTX, ≥1 g/m²) for the prevention of central nervous system (CNS) recurrence in patients with intravascular large B-cell lymphoma (IVLBCL), we reviewed 51 patients with pathologically diagnosed untreated IVLBCL. In total, there were five cases of CNS relapse (9.8%), and the 12-month CNS relapse rate was 9.2%. No statistical difference in CNS relapse rate (p = 0.86) was observed between patients with and without HD-MTX (n = 20 and 31, respectively). Furthermore, the composite endpoint defined as either CNS and/or neurolymphomatosis relapse was not significant in terms of the administration of HD-MTX (p = 0.25). No significant predictor of CNS relapse was found. In conclusion, patients with IVLBCL are at high risk of CNS recurrence; however, HD-MTX administration may not be effective for CNS recurrence prophylaxis. Key pointsThe administration of HD-MTX for patients with untreated IVLBCL may not be effective for preventing CNS relapse.

Neoplastic nerve lesions

Though metastasis and malignant infiltration of the peripheral nervous system is relatively rare, physicians should have a familiarity with their presentations to allow for prompt diagnosis and initiation of treatment. This article will review the clinical presentations, diagnostic evaluation, and treatment of neoplastic involvement of the cranial nerves, nerve roots, peripheral nerves, and muscle. Due to the proximity of the neural structure traversing the skull base, metastasis to this region results in distinctive syndromes, most often associated with breast, lung, and prostate cancer. Metastatic involvement of the nerve roots is uncommon, apart from leptomeningeal carcinomatosis and bony metastasis with resultant nerve root damage, and is characterized by significant pain, weakness, and numbness of an extremity. Neoplasms may metastasize or infiltrate the brachial and lumbosacral plexuses resulting in progressive and painful sensory and motor deficits. Differentiating neoplastic involvement from radiation-induced injury is of paramount importance as it dictates treatment and prognosis. Neurolymphomatosis, due to malignant lymphocytic infiltration of the cranial nerves, nerve roots, plexuses, and peripheral nerves, deserves special attention given its myriad presentations, often mimicking acquired demyelinating neuropathies.

Clinical manifestations of, diagnostic approach to, and treatment of neurolymphomatosis in the rituximab era

Neurolymphomatosis (NL) is a rare manifestation of lymphoma, with limited evidence for optimal management. The largest patient series, 50 cases of lymphoma and leukemia, was published in 2010 with limited rituximab exposure. This study aims to evaluate the clinical presentation, diagnostic testing, and outcomes of NL in the rituximab era. Forty biopsy-proven cases of NL, in association with non-Hodgkin lymphoma (NHL), at the Mayo Clinic were retrospectively evaluated. B-cell NHL was associated with 97% of NL cases, of which diffuse large B-cell lymphoma (DLBCL) was the most common (68%). Primary NL, defined as neural involvement present at the time of diagnosis of lymphoma, was noted in 52% cases. Seventy percent of patients presented with sensorimotor weakness and neuropathic pain. Magnetic resonance imaging (MRI) was positive in 100% patients. Overall survival (OS) was significantly better for primary NL and NL associated with indolent lymphomas. Relapses were seen in 60% (24/40) of patients; 75% involved the peripheral or central nervous system at relapse. The use of rituximab in the frontline setting significantly impacted progression-free survival (PFS). Transplant consolidation was noted to be associated with improved OS. This study adds to the available literature on NL in the rituximab era. The overall outcomes have improved in recent years. In our experience, MRI and positron emission tomography/computed tomography may be required for accurate assessment of the extent of disease involvement and identification of an optimal biopsy site. The use of rituximab was associated with improvement in PFS, and autologous stem cell transplant was associated with OS.

Analysis of clinicopathological features and prognostic factors of non-Hodgkin's intravascular large B-cell lymphoma

Non-Hodgkin's intravascular large B-cell lymphoma is a highly invasive extranodal lymphoma. The proliferating tumor cells invade the small vessels and capillaries of different organs. The clinical symptoms are atypical, there is lack of specificity, and the molecular and biological behaviors are not clear, thus, the present study aimed to improve the current understanding of non-Hodgkin's intravascular large B-cell lymphoma (IVL) and provide an accurate basis for clinical treatment and prognosis, by retrospectively analyzing and summarizing the clinicopathological features, immunohistochemical findings and molecular characteristics of 17 patients with IVL. The Kaplan-Meier method and log rank test were implemented to determine survival outcomes. Fisher's exact test was used to determine the association between clinicopathological features and the expression levels of Ki-67, c-Myc, B-cell lymphoma 6 (Bcl-6) and B-cell lymphoma 2 (Bcl-2), while multivariate Cox regression analysis was performed to identify the independent risk factors that affect the survival rates of patients with IVL. P<0.05 was considered to indicate a statistically significant difference. Among the 17 patients with IVL, 13 cases (76.47%) occurred in the adrenal gland and four cases (23.53%) occurred on the skin demonstrated positive IgH gene rearrangement. FISH analysis indicated that cleavage of the c-Myc gene was closely associated with sex, hypertension status and tumor size, while cleavage of the Bcl-6 gene was closely associated with tumor size parameters. Overall, the results suggest that the Ki-67 proliferation index is an independent risk factor for the prognosis (survival time) of patients with IVL.

Molecular profiling of primary central nervous system lymphomas - predictive and prognostic value?

PURPOSE OF REVIEW

Primary central nervous system lymphoma (PCNSL) is a rare but aggressive variant of non-Hodgkin lymphoma. The diagnostic gold standard remains the pathologic review of tumor tissue mainly collected though biopsies. The majority of PCNSL are diffuse large B cell lymphoma (DLBCL). Biopsies are invasive procedures, and there have been efforts to develop minimally invasive diagnostic testing using serum and cerebral spinal fluid. This article reviews multiple markers that could potentially serve as future diagnostic tools and predictors of treatment response.

RECENT FINDINGS

Many studies have attempted to classify DLBCL into different subtypes for prognostic purposes using methods such as immunohistochemistry. PCNSL often falls under the activated B-cell-like subgroup, and further genomic sequencing has identified alterations in genes within the B-cell receptor signaling axis at increased frequencies. Two such genes, MYD88 and CD79B, implicate the involvement of the NF-kB (nuclear factor kappa-light-chain enhancer of activated B cells) pathway, and targeted agents to this pathway are currently being used in the treatment of relapsed/refractory PCNSL.

SUMMARY

Although recent genomic profiling of PCNSL has increased the understanding of drivers in this disease and has also led to the introduction of targeted inhibitors, these markers have not yet been used for diagnostic and/or prognostic purposes. Further studies will need to evaluate if they hold great diagnostic potential.