Axel Grothey, MD, discusses left- versus right-sided tumors in colorectal cancer.
Axel Grothey, MD, a medical oncologist and director of Gastrointestinal Cancer Research at West Cancer Center and Research Institute, discusses left- versus right-sided tumors in colorectal cancer (CRC).
In CRC, the location of the primary tumor plays a major role in tumor biology and treatment selection, says Grothey; however, the definition of sidedness is still unclear.
Moreover, although Europe and the United States have different viewpoints regarding sidedness, it is widely understood that CRC, whether sigmoid or descending, is left-sided.
Studies have shown that right-sided tumors tend to be more aggressive, and patients have a shorter overall survival upon metastasis, explains Grothey.
Additionally, these studies demonstrated that right-sided tumors do not benefit from EGFR inhibitors, such as cetuximab (Erbitux) or panitumumab (Vectibix) in the first-line setting. Conversely, bevacizumab (Avastin) has shown benefit in right-sided tumors, Grothey concludes.