Gene-Expression Profiling to Understand Cancers of Unknown Origins
/Phase 2 Trial Examines Gene-Expression Profiling for Cancer of Unknown Primary Site
A randomized phase 2 trial examining the assignment of treatment based on gene-expression profiling compared with standard chemotherapy for patients with cancer of unknown primary site showed no improvement in the 1-year survival rate with the more tailored approach. However, several caveats may limit the relevance of the findings. A report of this study was published in the Journal of Clinical Oncology.1
Cancer of unknown primary site (CUP) refers to malignancies in which the originating tumor type cannot be identified. As a result, determining the best treatment for this cancer, diagnosed in approximately 31,000 people in the US each year, is extremely difficult.2 In recent years, oncologists have looked to genetic testing to identify the cancer type as a way to improve care.
In the current study, a molecular analysis of biopsied tissue predicted the originating cancer site for all of the 101 patients treated. The analysis identified a total of 16 sites; cancers of the pancreas (21% of participants), gastric system (21% of participants), and malignant lymphomas (20% of patients) were the 3 most common sites to be predicted as the primary site of malignancy. The Japan-based researchers then randomized the patients to receive therapy appropriate to the predicted site of origin (50 patients) or the standard, empiric treatment of paclitaxel plus carboplatin (51 patients).