Dr. Kallur is the director of molecular imaging and nuclear medicine at HCG Cancer Centre.

Dr. Kallur's expertise lies in general nuclear medicine, PET CT imaging, and his special areas of interest include theranostics and radiopharmacy. 

Dr. Kallur established the Nuclear Medicine Department at HCG in 1996 and he has been serving as the director of the department since then.

Dr. Kallur played a significant role in establishing India’s first FDA-compliant Cyclotron and PET radiopharmaceutical unit.

Dr. Kallur is a member of the Society of Nuclear Medicine (India) and the Association of Nuclear Cardiology Society of India.            

 He is also a founder member of the Association of Nuclear Medicine Physicians of India (ANMPI).

He has authored several national and international publications and presented papers at various conferences around the world.