Prophylactic CNS directed therapy in systemic diffuse large B cell lymphoma

Patient selection and tolerability of high-dose methotrexate as central nervous system prophylaxis in diffuse large B-cell lymphoma

INTRODUCTION

Central nervous system (CNS) relapse in diffuse large B-cell lymphoma (DLBCL) is usually fatal. Risk stratification of patients has historically been poorly defined, and CNS prophylaxis with high-dose methotrexate (HDMTX) can be associated with multiple toxicities. The CNS International Prognostic Index (IPI) defines three patient risk groups for CNS disease. The aims of this study were to evaluate the toxicity of HDMTX and describe outcomes in HDMTX and non-HDMTX patients according to the CNS-IPI.

METHODS

205 patients diagnosed with DLBCL between 2004 and 2014, initially treated with RCHOP-like chemotherapy and considered for HDMTX CNS prophylaxis were identified by pharmacy records at two teaching hospitals. Patient records were retrospectively reviewed for HDMTX toxicity, CNS-IPI calculation and CNS relapse.

RESULTS

28 patients with DLBCL were selected for two doses of HDMTX. Two of 28 patients received only one dose, and three had their second dose reduced due to renal impairment. 28% of patients experienced nephrotoxicity. 24 HDMTX and 122 non-HDMTX patients were evaluable for the CNS-IPI. No significant difference in the CNS-IPI distribution between the two groups was identified (p = 0.695). Five patients had CNS relapse, two who received HDMTX and three who did not. No significant difference in CNS relapse rate was identified between 24 HDMTX patients propensity-matched to 24 non-HDMTX patients.

CONCLUSIONS

HDMTX was well-tolerated by patients. Application of the CNS-IPI identifies a different population of candidates for CNS prophylaxis compared to traditional criteria.

Cerebrospinal fluid biomarkers of malignancies located in the central nervous system

CNS malignancies include primary tumors that originate within the CNS as well as secondary tumors that develop as a result of metastatic cancer. The delicate nature of the nervous systems makes tumors located in the CNS notoriously difficult to reach, which poses several problems during diagnosis and treatment. CSF can be acquired relatively easy through lumbar puncture and offers an important compartment for analysis of cells and molecules that carry information about the malignant process. Such techniques have opened up a new field of research focused on the identification of specific biomarkers for several types of CNS malignancies, which may help in diagnosis and monitoring of tumor progression or treatment response. Biomarkers are sought in DNA, (micro)RNA, proteins, exosomes and circulating tumor cells in the CSF. Techniques are rapidly progressing to assess these markers with increasing sensitivity and specificity, and correlations with clinical parameters are being investigated. It is expected that these efforts will, in the near future, yield clinically relevant markers that aid in diagnosis, monitoring and (tailored) treatment of patients bearing CNS tumors. This chapter provides a summary of the current state of affairs of the field of biomarkers of different types of CNS tumors.

Central Nervous System Prophylaxis for Aggressive B-cell Lymphoma: Who, What, and When?

Central nervous system (CNS) relapse of aggressive B-cell lymphoma is a rare but serious complication with poor survival. Different approaches have been used to define risks factors for CNS relapse and establish prophylactic measures. Although patients with low or intermediate risk of CNS relapse should not undergo special diagnostic or therapeutic measures, CNS MRI as well as cytology and flow cytometry of the cerebrospinal fluid are suggested for high-risk patients (and patients with testicular involvement) at diagnosis, and prophylactic high-dose methotrexate in patients without proven CNS involvement. Future risk and treatment models may include molecular features and new treatment options.

FDG-Avid Intrathecal Inflammation Following Administration of Intrathecal Methotrexate

Intrathecal methotrexate is a standard option for central nervous system-directed therapy in patients with stage III and IV diffuse large B-cell lymphoma. We present a case of a 50-year-old man with stage IV diffuse large B-cell lymphoma with widespread lymphomatous involvement including the central nervous system, who received 7 doses of intrathecal methotrexate via Ommaya catheter. Posttherapy F-FDG-PET/CT imaging demonstrated diffuse, intense intrathecal FDG avidity, without correlative findings on MR spinal imaging. FDG avidity resolved on follow-up. These PET/CT findings are most consistent with methotrexate-induced thecal inflammation, which needs to be distinguished from intrathecal malignancy.

Guidelines for diagnosis, prevention and management of central nervous system involvement in diffuse large B-cell lymphoma patients by the Spanish Lymphoma Group (GELTAMO)

Diffuse large B-cell lymphoma patients have a 5% overall risk of central nervous system events (relapse or progression), which account for high morbidity and frequently fatal outcomes,¹ and shortened overall survival of <6 months.² Early diagnosis of central nervous system events is critical for successful treatment and improved prognosis. Identification of patients at risk of central nervous system disease is critical to accurately identify candidates for central nervous system prophylaxis vs.

THERAPY

^3-5 This report by the Spanish Lymphoma Group (GELTAMO) aims to provide useful guidelines and recommendations for the prevention, diagnosis, and treatment of central nervous system diffuse large B-cell lymphoma patients with, or at risk of, leptomeningeal and/or brain parenchyma lymphoma relapse. A panel of lymphoma experts working on behalf of GELTAMO reviewed all data published on these topics available in PubMed up to May 2016. Recommendations were classified according to the Grading of Recommendations Assessment Development and Evaluation (GRADE) approach.⁶ A practical algorithm based on the proposed recommendations was then developed (Figure 1). Initial discussions among experts were held in May 2014, and final consensus was reached in June 2016. The final manuscript was reviewed by all authors and the Scientific Committee of GELTAMO.

[A case of bilateral blephaloptosis resulting from midbrain lesions caused by diffuse large B-cell lymphoma]

We report the case of a patient with bilateral blephaloptosis associated with a recurrence of diffuse large B-cell lymphoma (DLBCL) in the midbrain. A 70-year-old man experienced acute onset bilateral blephaloptosis; the other ocular movements, except for medial rectus muscle in the right eye, were not impaired. Pupils were isocoric and light reflexes were prompt. Other cranial nerves were intact. Gadolinium-enhanced MRI revealed abnormal enhancement in the midbrain and peri-ventricular regions. FDG-PET revealed an abnormal positive signal in the midbrain, similar to the distribution seen in the MRI scan. Cytology of the cerebrospinal fluid showed large atypical lymphocytes. These findings suggest that the recurrence of DLBCL in the midbrain caused bilateral blephaloptosis. The oculomotor fascicle is localized in the paramedian ventral midbrain. The fascicular fibers are divided topographically into four regions; the lateral, medial, rostral and caudal regions. In three-dimensional arrangement of the oculomotor fascicle, the fibers to the levator palpebrae superioris muscle and medial rectus muscles are located adjacently in caudal regions. Thus, we speculate that recurrence of DLBCL in the midbrain involving the right oculomotor fascicle caused blephaloptosis in the right eye, and then, infiltration of DLBCL to the left oculomotor fascicle subsequently caused blephaloptosis in the left eye. This is a valuable case to be documented in which neurological site of lesions consistent with those are found in radiological study.

Influence of Rituximab on Central Nervous System Relapse in Diffuse Large B-Cell Lymphoma and Role of Prophylaxis--A Systematic Review of Prospective Studies

Despite the improvement in overall survival in patients with diffuse large B-cell lymphoma (DLBCL) in the rituximab era, the occurrence of central nervous system (CNS) relapse heralds a very poor prognosis. The evidence is conflicting on the incidence and pattern of CNS relapse in the rituximab era compared with before the rituximab era and on the role of CNS prophylaxis. We conducted a systematic analysis of the data from 7 prospective studies, studying the incidence and type of CNS relapse, the role of prophylaxis, and survival after CNS relapse, with and without rituximab-based chemotherapy. No statistically significant difference was found in the incidence of CNS relapse with the use of rituximab-based chemotherapy compared with CHOP (cyclophosphamide, doxorubicin, vincristine [Oncovin], prednisone) chemotherapy. Leptomeningeal disease was more common and the survival after CNS disease was better in the rituximab era. No difference was found in the incidence of isolated CNS relapse. Chemoprophylaxis significantly decreased the incidence of CNS recurrence. The use of rituximab has not influenced the incidence of CNS relapse compared with the use of CHOP. Chemoprophylaxis plays a significant role in high-risk patients with DLBCL in decreasing CNS recurrence. Large randomized clinical trials are warranted to differentiate between intrathecal and systemic chemoprophylaxis.