Which system contains classifications based on tumor grade and cell type rather than tumor size or location?

The classification system that focuses on tumor grade and cell type rather than size or location is indeed the classification for brain and spinal cord cancers. This approach is significant because brain tumors, in particular, have unique biological behavior and characteristics that are often more relevant to treatment and prognosis than the traditional staging systems, which typically emphasize size and extent of disease spread.

In brain and spinal cord cancers, classification is based on the specific type of cells involved (such as gliomas, meningiomas, or metastatic tumors) and their grading, which reflects how abnormal the tumor cells appear under a microscope and indicates how likely the tumor is to grow and spread. Because these tumors originate in specific tissues with their complex biology, their classification often prioritizes these cellular characteristics over the size of the tumor or its anatomical location.

The AJCC Staging System and the FIGO Staging System, on the other hand, are more focused on criteria such as tumor size, lymph node involvement, and metastasis, which make them less applicable in contexts where histology and cell type are the more crucial factors for prognosis and treatment planning. Thus, the correct answer relates directly to the specific method of classification applicable to brain and spinal cord cancers, highlighting the significant differences in how various cancers are categorized