A new study, published in the journal Cell, found that classifying cancer tumors by their molecular structure instead of the tissue or organ may lead to more accurate diagnoses and potentially better treatments and outcomes for patients.

Through analyzing over 3,500 samples from 12 cancer types -such as breast, kidney and bladder,    researchers found at least 10% of tumors (possibly as high as 30 to 50 % ) would be identified differently if oncologists determined their diagnoses by a tumor’s molecular makeup.

Additionally , tumor samples on a molecular level appeared to look more like unrelated cancers. For an instance, a significant number of squamous head-and-neck cancers looked more like some squamous-cell cancers found in the lung.

They also found that in many of the cancer types, such as an aggressive form of brain tumor known as glioblastoma and a type of leukemia, the tumor samples matched up well with the tissue classifications, suggesting that a tumor’s location is still important for certain types of cancers.

Usage for New cancer classification system

Many cancers, which are yet sequenced, are added into the genomic “map”, including breast, kidney, bladder, brain, colon, endometrial and lung. It enable doctors to figure out whether an existing therapy for one cancer will work for a subtype of a seemingly different cancer.

The discovery that some tumors shared molecular similarities with tumors from other parts of the body was particularly striking in bladder cancer. It may help explain why some bladder cancer patients respond much differently to treatment than others.

Reference:

Multiplatform Analysis of 12 Cancer Types Reveals Molecular Classification within and across Tissues of Origin. Cell.2014.06.049