About 15% of people with mutated NF1 gene the benign tumors convert into aggressive cancer form known as malignant peripheral nerve sheath tumor
. The patients with MPNST have poor prognosis as the cancer spreads quickly and becomes resistant to radiation and chemotherapy.
‘The blood test is a highly effective and inexpensive approach to detect cancer in people with NF1 (neurofibromatosis type 1).’
According to Jack F. Shern, co-author of the study “Imagine going through life with a cancer predisposition syndrome like NF1. It’s kind of like a ticking bomb.” “The doctors are going to be watching for cancerous tumors, and you’re going to be watching for them, but you really want to discover that transformation to cancer as early as possible.”
Biopsies, MRI scan and PET scan are used to identify whether the benign plexiform neurofibromas are converted into MPNST. The biopsy findings are not always accurate and the procedure is highly painful as the tumors grow along the nerves. The imaging tests are very expensive and not accurate.
A simple blood test was developed by the scientists to identify whether the non-cancerous form is converted to cancerous form. Blood samples of 23 people with plexiform neurofibromas ,14 people with non-treated MPNST and 16 healthy people without NF1 were collected from young adults. The cell-free DNA (DNA shed from cells into the blood) was isolated and gene sequences to see the difference between the genetic material among the three groups.
The results showed that:
The cell free DNA in patients with MPNST was different compared to other two groups. It had shorter pieces of DNA compared to the other two groups of people. The plasma tumor fraction (a proportion of cell-free DNA that comes from tumors) was high.
The test was 86% accurate. The study also showed how well the MPNST responded to the treatment. If the plasma tumor fraction reduces the size and the number of tumors gets reduced and if the plasma tumor fraction increases then it is associated with metastatic recurrence.
Dr. Shern says “You can imagine treating a patient with a chemotherapy regimen. This blood test could easily and rapidly allow us to determine whether the disease is going down or maybe even going away entirely, “And if you had done surgery and taken out an MPNST, and the blood test was negative, you could use that to monitor the patient going forward to see if the tumor returns.”
The blood test is a simple and inexpensive method for the early detection of cancer and it can be used in poor and developing countries.
Source: Medindia
