Because of the unique nature of these rare tumors, the ability to predict metastasis and recurrence could have "a very important impact on (patient) follow-up as well as treatment options," said Dr. Pacak, also of the NICHD.
The investigators are hopeful that the outcomes of ongoing prospective studies over the next 2-3 years – including possible studies in thyroid, ovarian, and kidney cancer, will lead to the use of CPE-delta N as a biomarker for metastasis in clinical practice in the next few years.
"This biomarker may be useful for many types of cancer, and I think that’s very important," said Dr. Loh, noting that no other accurate biomarker of this type currently exists.
Along with Dr. Pacak and Dr. Stephen M. Hewitt of the Center for Cancer Research in Bethesda, Md., who also spoke during the telebriefing, Dr. Loh stressed that this biomarker is unlike others that have been reported on in the past, but which proved disappointing in their ability to identity and improve prognosis in cancer, because it meets each of 20 criteria (REMARK Criteria) that have been set forth by various cancer societies for reporting on biomarkers, and as required for publication in the Journal of Clinical Investigation.
Indeed, they concluded in their article that "(CPE-delta N’s) assay provides a major breakthrough in biomarker discovery with invaluable utility in cancer prognosis for predicting future metastasis and recurrence in patients with HCC and PHEO/PGL, and potentially for other types of cancer as well."
Still, although CPE-delta N in this study "beats the current standard of care and grading," ... biomarker development – much like drug development – takes time, because outcomes must be determined, Dr. Hewitt said.
"We have a discovery and a very good result, and it’s time to validate this in other cohorts and expand these findings, including to other tumor types," he said.
This study was supported by the National Cancer Institute, the NICHD, the University of Hong Kong, and the Canadian government.