Diagnosis and Management of Multifocal Gliomas

Abstract

Patients who present with multiple cerebral tumors are usually considered as having metastatic disease. If they have a history of a primary cancer in another site, the brain tumors are considered metastases and are usually managed with standard whole-brain radiotherapy. If no primary cancer site is known, a diagnostic work-up is performed, but if no primary site is found, they are still considered as brain metastases from an unknown primary site. Thus, such patients can either have brain biopsy (recommended) for further diagnostic consideration or, occasionally, they can be treated with whole-brain radiotherapy, depending on the age, performance status and wish of the patient. However, in some of these patients the multiple brain tumors represent multifocal glioma rather than metastases, resulting in incorrect treatment. In such cases, various MRI characteristics may be helpful in directing towards the correct diagnosis. Thus, patients who present with multiple brain tumors should not always be considered to have metastatic disease even if they have a previous diagnosis of systemic cancer, and multifocal glioma should be ruled out.

Multifocal epithelial tumors and field cancerization: stroma as a primary determinant

“…The association of this process with pancreatic and ovarian cancer is less appreciated but probably equally important (5). Field effects have also been implicated in nonepithelial cancer types, such as melanoma (37) and brain tumors (38). Further, bone marrow field effects have been invoked to explain the development of secondary myelodysplastic syndrome and/or acute leukemia in patients initially diagnosed with severe aplastic anemia (39,40).…”

The management of incidental low-grade gliomas using magnetic resonance imaging: systematic review and optimal treatment paradigm

“…For example, if a meningioma necessitates surgical intervention, it may be prudent to resect a nearby incidental LGG in the same surgery. 5,7,13 Age-Dependent Classification When determining treatment for incidental LGG, the neurosurgeon may be compelled to alter his or her decisions based on the age of the patient at diagnosis. For example, younger patients may be more prone to receive surgery earlier due to parent's anxiety of "observing" children with incidental LGG.…”

Multifocal and multicentric glioblastoma: Improved characterisation with FLAIR imaging and prognostic implications

“…Our results demonstrate, however, that the majority of glioblastomas with multiple enhancing regions are multifocal rather than multicentric, with apparently true multicentricity being rare. Giannopoulos and Kyritsis have previously stated that ''a strict definition between multicentric and multifocal gliomas has no practical clinical value" [18]. This statement was likely influenced by the inaccuracies of older neuroimaging, but we nevertheless agree.…”