- Merkel cell carcinoma (MCC) has a high chance of recurrence in patients who have been cured of it.
- A new blood test will help detect the likelihood of recurrence of MCC.
- The test works by measuring an antibody against a cancer-driving protein from the virus that causes MCC.
A test that works by measuring the presence of a novel marker will help detect the possibility of recurrence of a deadly cancer-Merkel cell carcinoma (MCC).
MCC is a rare cancer that kills one among every three who develop it.
The recurrence rate of MCC is very high. It is several times more likely to recur than melanoma and hundreds of times more likely than basal cell carcinoma. Even if patients are diagnosed at a very early and lowest-risk stage of this cancer, it has a 20% risk of recurring.
The test works by measuring an antibody against a cancer-driving protein from the virus that causes MCC.
It is an easy, efficient and cost-effective method that helps to identify the risk of recurrence of MCC among patients who successfully undergo treatment.
Earlier research by Dr. Paul Nghiem and colleagues had stated that the immune system can be mobilized to effectively attack MCC.
The new blood test will make a major difference as detecting MCC early means that immunotherapy has a higher chance of working.
"Catching and treating the recurrence before it has a chance to grow large - the difference between a cancer the size of a grape and one the size of a grapefruit - enhances the chances that immune therapy will work," said Nghiem.
The prevailing method of detecting MCC is through radiological imaging.
In the latest study researchers recruited 219 patients who had initially been succefully treated for MCC with surgery and/or radiation.
The researchers then compared the new blood test with radiological imaging for MCC detection.
Benefits of Blood Test over Traditional Imaging
- the test was better at picking up small traces of the cancer when it first returns-in many cases well before tumors were visible by imaging.
- the test is also much less expensive.
- spares patients from exposure to the radiation and contrast dye associated with imaging.
The test is not practical for the initial diagnosis of MCC because the disease is so uncommon. Its main use is to detect recurrences earlier.
Nearly half of the study participants did not produce the antibodies which is a marker for the test. Such patients will not produce these antibodies even when the cancer returns.
Those who test negative are 42%t more likely to have a recurrence. So getting the test done is useful for all patients, including those found not to produce the antibodies.
If the recurrence of MCC is caught early, these patients may particularly benefit from immune therapy.
"The findings highlight how monitoring the robustness of the immune system provides key insights into cancer treatment, and they are emblematic of a broader shift in how physicians can track disease," said Nghiem. "It underscores a key tenet of immune therapy - that your immune system is naturally attuned to fighting cancer and the challenge is how best to harness that."
Dr. Paul Nghiem, is the senior author of the paper. He is a member of Fred Hutchinson Cancer Research Center, the head of the Division of Dermatology at the University of Washington medical school and a clinician at the Seattle Cancer Care Alliance. The paper is published on December 7th in the journal Cancer.