CANCER remains to be one of the top three killer diseases in the country, next only to ischemic and cerebrovascular diseases. The difficult part for most cancers is that some are detected when it is at its more serious stage already, where treatment and recovery would be next to impossible for certain patients.
However, the future of early cancer detection in the Philippines remains to be bright through a new technology that will soon be available in the country to help fight cancer called Next Generation Sequencing (NGS).
ACCORDING to Dr. Eugene Odoño, Medical Specialist III at the Department of Laboratories of the UP Philippine General Hospital (UP-PGH), cancer is defined as the abnormal growth of cells that may lead to the formation of tumors. While the existence of a tumor does not necessarily mean it is cancer, most cancers, except those in the blood, can create tumors. Cancer may also deprive the body of nutrition and can also destroy other organs and muscles in the body.
Cancer may generally be formed when the DNA in the genes that guide the growth of cells experience changes that is called “mutation.” It then goes on a destructive stage when it goes to spread to other parts of the body or what is called “metastasis,” Dr. Odoño explained during the last Stop C.O.V.I.D. Deaths webinar titled “Labanan ang Kanser: Next Generation Sequencing (NGS) Parating Na!” a webinar organized by the University of the Philippines, the UP Manila NIH National Telehealth Center and in cooperation with UP-PGH.
He said there are at least three basic forms of providing cure for cancer: surgery that aims to remove the tumor, chemotherapy where it strives to kill cancer cells and also includes immunotherapy and hormonal therapy, and lastly radiation or radiotherapy.
But how to determine what treatment would best suit a patient? Would it be just surgery, or would chemotherapy suffice? Dr. Odoño, however, believes that the appropriate treatment depends on the type of cancer, or on the “stage” or level of coverage of cancerous cells and how it has already spread throughout the body. “These will help you and your doctor decide which appropriate mode of treatment can be done. This will also help in informing the family of the patient on the chances of recovery or prognosis,” Dr. Odoño stressed.
Traditional or modern?
AT present, the way of determining the type and stage of cancer in a patient is through traditional means such as a histopathologic examination or “biopsy,” where cells are extracted from the patient’s tumor, or through “excision biopsy” where the tumor is removed then examined by a pathologist through a microscope. On the other hand, Dr. Odoño said the stage of a cancer is determined through x-rays, MRIs, CT scan, bone scan or PET scan.
But what if there is a way to read the DNA in the genes? Dr. Odoño said there is an existing technology called “molecular diagnostics” that is now used against cancer. This test checks the DNA or genes in the cells and blood that can help determine if cancer is present or not, the type of cancer it is, or what are its mutations. Through molecular diagnostics, knowing the mutations in cancer can help determine which type of cancer it is, which type of medicine will work or not, and know the chances of recovery.
One example of a molecular diagnostic test is eGFR or estimated glomerular filtration rate testing for lung cancer, which is done to check if there are mutations that can be treated by a particular type of medicine.
Unfortunately, there are only a few institutions that offer molecular diagnostic tests for cancer, Dr. Odoño pointed out, and mostly found in bigger hospitals in progressive cities, and many of them can only check one gene per testing to find out if there is mutation or not.
Hope for cancer testing through NGS
THIS is why in the Department of Laboratories of the UP-PGH, Dr. Odoño said, they are already trying if they can put up Next Generation Sequencing or NGS test, a type of molecular diagnostic test wherein several genes are examined and read simultaneously. “With NGS, we have what we call ‘panels,’ or a list of genes that is searched for and examined in each panel. Using modern and efficient technology, the genes in the list can be read simultaneously.”
One of the notable advantages of NGS is that it can search for mutations in dozens of genes in just a single test, and increases the possibility of finding more mutations. Results are known much faster because it can test several genes and not one at a time just like before, and only a small amount of tissue can be extracted to test as many genes as possible.
But just like any modern technology, NGS is quite expensive. But since cancers have so many mutations, testing through NGS will be worth every peso spent if more genes can be tested.
Still, Dr. Odoño said the best way is to ask your physician if NGS can be done based on your ailment since the doctor will be the one to explain the results, give advice on next steps to take, and how the test results can be used in the treatment of cancer.
“Because of its outstanding benefits, the UP-PGH is trying its best to help establish NGS by this year for the benefit of our fellow Filipinos and those who have cancer,” Dr. Odoño stressed.