Resection of PCNSL, if safely possible, seems to be better than biopsy: challenging a paradigm?

Primary Diffuse Large B-Cell Lymphoma of Central Nervous System: Is Still Surgery an Unorthodox Treatment?

Primary central nervous system lymphoma (PCNSL) is characterized as an extra-nodal non-Hodgkin lymphoma which develops from the neuraxis. The purpose was to report a case of a patient with a supra-tentorial tumor who underwent subtotal resection of his tumor as his biopsy was not indicative of a PCNSL tumor and had uneventful recovery until his last follow-up. A 42-year-old man was admitted to our department for generalized epileptic seizures. CT and MRI examinations revealed a tumor in his right parietal-occipital lobe that was surrounded by edema and was enhancing after gadolinium administration. The patient underwent a navigation-assisted parieto-occipital craniotomy and posterior parietal transcortical approach for tumor biopsy which was not indicative of PCNSL tumor. The surgical team decided to remove the tumor on site. Histological analysis of the resected specimen showed primary diffuse large B-cell lymphoma. Combined chemotherapy and radiation therapy was applied to the patient, and at his last follow-up (16 months), he is tumor free. In our case as in several other studies during the last decade, the outcome after the surgical resection of a PCNSL tumor in combination to radiation and chemotherapy was unexpectedly good. The role of surgery probably should be reconsidered for single lesion PCNSL tumors.

MicroRNAs as Potential Biomarkers for Diagnosing Cancers of Central Nervous System: a Meta-analysis

Recent studies have shown abnormal microRNA (miRNA) expression levels in the central nervous system (CNS) of cancer patients, suggesting that miRNAs may serve as promising biomarkers for cancers of CNS. However, other studies have arrived at conflicting results. Therefore, this meta-analysis aims to systematically measure the potential diagnostic value of miRNAs for CNS cancers. Electronic databases as well as other sources were searched until to April 12, 2014 for relevant articles. Data from different studies were pooled using the random-effects model. The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative LR (NLR), diagnostic odds ratio (DOR), together with the summary receiver operator characteristic (SROC) curve, and area under the SROC curve (AUC) value were used to estimate overall diagnostic performance. Twenty-three studies from 6 articles were included in the current meta-analysis with a total of 299 CNS cancer patients and 418 controls. The pooled sensitivity, specificity, PLR, NLR, DOR, and AUC were 0.85 (95% CI, 0.80-0.89), 0.83 (95% CI, 0.76-0.88), 5.1 (95% CI, 3.4-7.5), 0.18 (95% CI, 0.12-0.26), 28 (95% CI, 14-58), and 0.91 (95% CI, 0.88-0.93), respectively. Subgroup analyses showed that cerebrospinal fluid (CSF)-based miRNAs assays yielded more accurate results and seemed to be more sensitive in diagnosing of primary central nervous system lymphoma (PCNSL). In conclusion, miRNAs may be suitable for serving as noninvasive biomarkers for CNS cancers detection. However, further validation based on a larger sample of patients and controls is still required.

Serum miR-21 is a diagnostic and prognostic marker of primary central nervous system lymphoma

The standard of care for primary central nervous system lymphoma (PCNSL) is systemic chemotherapy with or without whole brain radiotherapy or intrathecal chemotherapy. In contrast to treatment for other brain tumors, efforts at resection are discouraged. However, it is difficult to distinguish PCNSL from other central nervous system tumors which need aggressive surgery in both CT and MRI images. In this study, we assessed whether measurement of miR-21 in the serum could improve diagnostic accuracy for PCNSL. We found that serum miR-21 significantly increased in PCNSL when compared with other brain tumors and normal controls in both test and validation cohort. Further, serum miR-21 could discriminate PCNSL from all controls with an area under the curve of 0.930 for the test cohort and 0.916 for the validation cohort in ROC analysis. Similar results were also obtained in the validation cohort. Besides, raised concentrations of miR-21 in serum could differentiate PCNSL from glioblastoma under the curve of 0.883 for the test cohort and 0.851 for the validation cohort in ROC analysis. Furthermore, Kaplan-Meier curve analysis (p = 0.03 for test cohort and 0.02 for validation cohort) and Multivariable Cox regression (p = 0.03 for test cohort and 0.01 for validation cohort) revealed serum miR-21 as an independent and powerful predictor of overall survival. Taken together, our results demonstrate that serum miR-21 may represent a diagnostic and prognostic marker for PCNSL.