Functional preservation is critical in @entity11 surgery, and the extent of resection influences survival outcome. Neoadjuvant chemotherapy is a promising option because of its potential to facilitate @entity5 shrinkage and maximum @entity5 resection. The object of this study was to assess the utility of the neoadjuvant strategy in a prospective series of @entity11 with favorable molecular status. Twenty-six consecutive cases of @entity11 of WHO grade II or III with either 1p19q codeletion or @entity8724 methylation were treated with upfront chemotherapy following maximal safe removal. In cases of incomplete initial surgery, second-look resection was intended after @entity5 volume decrease by chemotherapy. Among 22 evaluable cases, chemotherapy led to a median change in the sum of the product of perpendicular diameters of -35  %, and 14 out of the 22 cases (64  %) showed objective response. Second-look resection after @entity5 volume decrease was performed in 12 out of 19 cases of incomplete initial surgery (GTR/STR 9, removal of residual methionine PET uptake 3). The median progression-free survival among the 22 @entity1 with grade II @entity5 was 57  months, with some cases showing durable progression-free survival after second-look resection. @entity1758 indices of the second-look resected @entity5 were lower than those of the @entity5 , and the methylation status of the @entity8724 gene was unchanged. Neoadjuvant chemotherapy based on molecular guidance often produces significant volume decrease of incompletely resected @entity11 . Radical second-look resection is an optional advantage of upfront chemotherapy for chemosensitive @entity11 compared with initial radiotherapy.

Upfront chemotherapy and subsequent resection for molecularly defined XXXX .

@entity1 :: ('9606', 'Species') :: ['patients'] @entity5 :: ('MESH:D009369', 'Disease') :: ['tumor', 'initial tumors', 'tumors'] @entity11 :: ('MESH:D005910', 'Disease') :: ['diffuse gliomas', 'glioma', 'gliomas'] @entity8724 :: ('4255', 'Gene') :: ['MGMT'] @entity1758 :: ('57534', 'Gene') :: ['MIB-1']
@entity11 :: (MESH:D005910,Disease) :: ['gliomas']
