Professor & Head of Nuclear Medicine Department of India’s premier institutions All India Institute Of Medical Science (AIIMS) CS Bal spoke to the Nuclear Asia about the progress of nuclear medicine in India and the challenges like shortage of manpower that contains the field from attaining its full potential. The seasoned doctor terms the nuclear medicine therapies as revolutionary in diagnosing and treating diseases like cancer.
If in India there is an authority of thyroid cancer it is you. As on this date how has the nuclear medicine progressed in the diagnostic aspect?
Nuclear medicine has undergone many significant changes not just in India but all over the world. The picture has totally changed post the year 2000. In an epic event in 2001 the PET (Positron Emission Tomography) scanner and CT (Computed Tomography) both merged and became one. So we had a combination of radiology and nuclear medicine. After that there has been a rise in PET scanner from one in 2000 to 160 in 2017.
Around 1600 patient are examined by PET scanner every day, which is a feat in itself. PET scanner is usually used for oncological applications. We have got variety of tracers while the most common is FDG (fluorodeoxyglucose). FDG is like the work horse of nuclear medicine now.
You need two things for PET, one is FDG which is produced by cyclotron and the other is the scanner. While the scanner is easy to procure but to establish a cyclotron is a difficult task, for that you need physicist, chemist, synthesize, quality control which in turn increases the cost of the dose. The yearly maintenance cost of cyclotron is INR 66,00,000. In standby mode a cyclotron consumes 5 KW of electricity which is 120 KW in a day. So you can see that it is a big white elephant.
Where does India stand when it comes to nuclear medicine?
We are the first in the world to have started the Doctor of Medicine programme in nuclear medicine therapy. For the last 60-70 years, Thyroid cancer, Thyrotoxicosis is going on and in such cases most of the patients die within few weeks or months. But if they are treated with radio nuclear therapy we can prolong their life. We have the longest surviving patient for 18 months. This can also replace joint surgery and anybody with joint disorders can get this treatment at a very nominal cost.
Recently a new kind of abdominal cancer have been diagnosed, the neuroendocrine tumour is becoming widespread. It’s already five times more in America. The best part is this can be treated with nuclear medicine.
Peptide Receptor Radionuclide Therapy (PRRT) is a very popular therapy to treat this form of cancer. For the last 10 years the horizon of therapy in nuclear medicine, which was previously limited to thyroid cancer only has been expanding in geometric progression. But unfortunately there is a lack of trained manpower.
We are now focusing on manpower, who will be trained exclusively on matters like how to handle the radioisotope. For eight years I tried and have finally got the approval from the government. They have realised now that therapy is going to be the next big thing like it happened when PET & CT scan merged after 2000.
Modern oncology i.e. treatment of cancer will change to a whole new level. It will be more of personalised in nature. Not like chemotherapy where the patient loses more than they gain.
What is the difference between nuclear medicine, chemotherapy and radiotherapy?
Nuclear medicine is a sub speciality of medical science which uses radio nuclides for diagnosis, treatment as well as for research.
Whereas radiotherapy is that branch of medical science which uses shield source. For example in the treatment of thyroid if radioactive iodine is administered then it will get concentrated on the thyroid and kill it. While in the case of radiotherapy, treatment is done through a cobalt source and expose the thyroid to the gamma rays which will eventually kill the thyroid cells. That’s why radiotherapy is called telecobalt (through a distance) therapy and nuclear medicine is called brachytherapy. In brachytherapy the radiation is administered in a closed circuit so that only the cells that are affected can be cured without affecting the surrounding organs and tissues.
Another type of therapy is called electron therapy. In this therapy an electron beam is used to cure certain areas where gamma rays cannot penetrate.
One has to understand that in radiotherapy the isotope does not touch the body whereas in nuclear medicine we use the isotope to touch the body.
Chemotherapy is totally different. Here we use chemicals for therapy. It originated in World War II when Adolf Hitler used it against the Jews. Then the scientists ideated that if it can cause death to humans then if administered in small quantity it could also cure cancerous cells in the human body.