Primary Central Nervous System Anaplastic Large Cell Lymphoma, ALK Positive

Anaplastic Lymphoma Kinase (ALK) in Posterior Cranial Fossa Tumors: A Scoping Review of Diagnostic, Prognostic, and Therapeutic Perspectives

Anaplastic Lymphoma Kinase (ALK) has been implicated in several human cancers. This review aims at mapping the available literature on the involvement of ALK in non-glial tumors localized in the posterior cranial fossa and at identifying diagnostic, prognostic, and therapeutic considerations. Following the PRISMA-ScR guidelines, studies were included if they investigated ALK's role in primary CNS, non-glial tumors located in the posterior cranial fossa. A total of 210 manuscripts were selected for full-text review and 16 finally met the inclusion criteria. The review included 55 cases of primary, intracranial neoplasms with ALK genetic alterations and/or protein expression, located in the posterior fossa, comprising of medulloblastoma, anaplastic large-cell lymphoma, histiocytosis, inflammatory myofibroblastic tumors, and intracranial myxoid mesenchymal tumors. ALK pathology was investigated via immunohistochemistry or genetic analysis. Several studies provided evidence for potential diagnostic and prognostic value for ALK assessment as well as therapeutic efficacy in its targeting. The available findings on ALK in posterior fossa tumors are limited. Nevertheless, previous findings suggest that ALK assessment is of diagnostic and prognostic value in medulloblastoma (WNT-activated). Interestingly, a substantial proportion of ALK-positive/altered CNS histiocytoses thus far identified have been localized in the posterior fossa. The therapeutic potential of ALK inhibition in histiocytosis warrants further investigation.

Primary Anaplastic-Lymphoma-Kinase-Positive Large-Cell Lymphoma of the Central Nervous System: Comprehensive Review of the Literature

BACKGROUND

Primary anaplastic-lymphoma-kinase (ALK)-positive large-cell lymphoma of the central nervous system (PCNS ALK-positive ALCL) is a rare entity, with a limited consensus reached regarding its management. While this pathology often presents as solitary lesions, the occurrence of multiple tumors within the brain is not uncommon. The lack of distinctive radiological features poses a diagnostic challenge, leading to delays in initiating targeted therapy.

METHODS

We conducted a comprehensive literature search, identifying seventeen publications for qualitative analysis.

RESULTS

The management options and reported patient outcomes in the literature varied significantly, emphasizing the need for a patient-specific approach. The emergence of ALK-specific inhibitors represents a new frontier in this field, demonstrating promising results.

CONCLUSION

PCNS ALK-positive ALCL necessitates a comprehensive understanding and optimized management strategies. A tailored therapeutic approach, integrating surgical intervention with radiotherapy and chemotherapy, appears pivotal in addressing this pathology. The implementation of a therapeutic protocol is anticipated for further advancement in this field.