The Future of Medicine - Srianee Dias

 THE FUTURE OF MEDICINE

 By Srianee Dias

When I first began practising pathology our diagnoses were made pretty much on morphology alone. The history, the location of the lesion, the gross and microscopic appearance also contributed to the final diagnosis which was made using basic hematoxylin and eosin stains, as well as a few other special stains.  The treatment decisions depended on the pathologist’s diagnosis.  In those days (late 1970s) when the diagnosis was malignant, the treatment options were few. 

      As time went on, various techniques became available to identify the unique properties of the malignant cells, which assisted the oncologists in choosing the most appropriate treatments for their patients.  This is especially true in the case of haematological malignancies.  Surgical pathologists began to sub-specialize as gastro-intestinal pathologists, breast pathologists, gynaecological pathologists, cytopathologists, hematopathologists etc. 

    Nowadays when a surgical pathologist encounters a malignant tumour it is deemed inadequate to simply diagnose the tumor based on only routine hematoxylin and eosin stains. A myriad of molecular studies need to be done and hormone receptors need to be assayed before the final diagnosis is made, because all these tests will definitely influence the treatment.  As an example in 2004, we began performing a test called Oncotype DX on breast cancer tissue samples, where the tumours were given a certain score.  But, it was 2015 before it was determined that patients with a certain score do just as well with hormone therapy alone, as with the more toxic chemotherapy.  Women had been unnecessarily exposed to the more harmful chemotherapy. 

   There are more and more technologies looming on the horizon.  Perhaps the H&E slides that we studied as medical students will become obsolete in diagnostic pathology. 

  The genetic make-up of the tumour is also important.  It is increasingly apparent that our own individual genetic combinations will also influence therapy, and not just in oncology. In the future, our genomes will be sequenced, stored, and the information saved for treatments that have been demonstrated to have had good results on similar gene types and combinations that we have. 

    In 1990 when the Human Genome Project was launched it took 10 years to be completed and cost a few billion dollars.  Today it is possible to study an entire genome of about 25,000 genes in a few days on a portable DNA sequencer called a MinION.  It costs about $1000.00 and connects to a laptop.  The Oxford Nanopore, a portable device is capable of sequencing DNA in humans, plants and microbes.  In the present stage of its development, the DNA has to be extracted from blood or tissue involving a multistep process. This will have to be simplified before this technology is widely available. 

    Ethical and privacy issues arise with all this information gathering.  People will have to be willing to share their data, and privacy ground rules will have to be established before this kind of technology is able to reap any benefits. 

    Knowing a person’s genome will allow effective targeted therapy against diseases.  Knowing a pathogen’s genome will also lead to effective targeted therapy against the pathogen.  (Think of all the damage we’ve inflicted on society with the irresponsible use of broad-spectrum antibiotics resulting in resistant organisms).  We’ve known for years that if a person is a carrier for G6PD deficiency the ingestion of fava beans could be fatal.  Certain medications can also cause hemolysis in these people.  We all know patients and family members who develop serious side effects after beginning treatment with a particular medication.  In the future there will be tests to identify one’s genetic predisposition to such reactions so that doctors can make the correct choice in treating their patients. 

    Targeted therapy is being used in oncology today and the range of medications is ever-expanding.  Targeting the malignant cells specifically helps to avoid the toxic side effects of standard chemotherapeutic drugs. 

   One of the therapies in current use is Chimeric Antigen Receptor T cells (aka CAR T cells)  These are T lymphocytes that have been genetically engineered to produce an artificial T-cell receptor for use in immunotherapy.  It gives these T-cells the new ability to target a specific protein.  It works this way:

        a) The T lymphocytes are separated from the patient’s blood.

        b) These cells are genetically altered in the lab so that they will specifically attack an antigen on the patient’s malignant tumour, but not the patient’s healthy cells.

        c) These altered T-cells are then re-infused into the patient where they will seek out and attack the patient’s malignant cells.

CAR T cells can be autologous (patient’s own cells) or allogeneic (donor cells).  These were first approved by the FDA in 2017 and now about five such therapies have been approved, mainly for the treatment of leukaemias, lymphomas and multiple myeloma. 

  In the future, it will be possible to scan a blood sample for circulating cell-free DNA (cf DNA).  It will identify the type of cancer a patient has and what type of therapy will work.  That is a far cry from what we had to do many years ago when a patient’s chest had to opened to obtain a tissue sample from a lung tumour.  With genomic information, we won’t even have to wait for a patient to develop symptoms. 

   We already have smartphones and devices strapped to our wrists (I refuse to call them watches!) that monitor our movements, heart rate, heart rhythm and breathing.  If we stumble and fall they automatically dial for help!  (911 in the US) Skin patches and under the skin implants will evolve to monitor additional information.  These devices may monitor your activities and in the future, when something is amiss, even make an appointment with your physician on your behalf. 

   Modified ink-jet printers are being used to print layers of living cells such as skin cells which have great potential for skin grafting.  These are still in the stage of animal research but have great promise.  It is possible that a person’s stem cells could be harvested and used for this purpose as well. 

   The future of medicine is exciting and vastly different from what it looked like when we started on our journey.  I have listed only a few advances which are relevant to my speciality of pathology.  There is much more happening in other specialities as well. 

   The only concern I have is that with all these advanced technologies available to them, physicians will lose their human touch.  They still need to look the patients in the eye, answer their questions, reassure and comfort them when needed.  I hope those qualities will not be pushed aside. 

NOTE:  I got the idea for this article while I was in the middle of reading a book entitled “Lifespan: Why We Age and Why We Don’t Have To” by David Sinclair, PhD with Matthew D. LaPlant.  It is about longevity, and the author predicts that people will be living much longer in the years to come.  He gets into a lot of scientific details, some of which I skimmed, but he made me think about the changes we have gone through when he started discussing some of these technological advances which I have listed.  I am only halfway through the book!   It is an interesting book crammed with information.