Radiation therapy in modern era
of cancer management:
Radiation therapy is being used
successfully in cancer treatment for more than a century and is one of the
corner stone of success in fight against cancer. In early days, radium, caecium, radon
capsules, which are radioactive materials were inserted in cervix for
management of cervical cancer. Dramatic response in these tumours had resulted
in interest with radioactive material in cancer management. Initial euphoria
regarding the usage of radioactive materials attracted many researchers and
there was surge in the indications of it's usage. The potential of gamma rays
and x-rays in damaging the tumour cells were used to cancer. With gamma and
x-rays, the tumour cell DNA is damaged more than the normal cells, and hence
tumour cells are killed where as normal cells are relatively spared. After
invent of x-rays, deep x-rays were used to treat tumours. Several x-ray
machines were introduced and x-ray was being used to treat almost all diseases
including peptic ulcer, ankylosing spondylosis (bone problem), psoriasis (skin
problem). However, the progress was halted with evidences of reactions, second
malignancies and other toxicities. There was a lull period for few decades in
the development of radiation oncology specialty. And, during 1960s and 70s
after the discovery of artificial radioactive materials, there was again revival
of this specialty with 'tele-cobalt' machines. There was 'simulator' for
planning treatment, scientific dose calculation methods, and accurate treatment
delivery technology. 'Shields' and 'blocks' were being used to protect normal
tissues and deliver higher dose of radiation to the target- 'tumour'. Favourable
outcome with this modern radiation therapy gave the required confidence to the clinicians
and more and more cancer patients were treated with radiation therapy with
success. However, still there was lot of limitations in both treatment delivery
and planning. There was no imaging to see the target, no proper computer
assisted planning tools and there was visible scope of improvement of treatment
delivery technology.
Modern day radiation therapy
coincided with the advent of computers, imaging and mechanical revolution and
also incorporation of technology in medical science. In 1990s, with advent of
computers, CT and MRI scan and most importantly active involvement of
technologists in research and development has revolutionized radiation therapy
speciality. Modern radiation therapy is one of the 'most sort after' and 'high
tech' medical specialty. Computer guided planning enables us to deliver high
dose of radiation to the tumour and spare normal tissues. Intensity modulated
radiation therapy and Image guided radiation therapy is the advanced radiation
therapy delivery technology with most modern techniques. Now, robotic
radiosurgery has enabled us to deliver high dose of radiation in very short
time and complete radiation therapy in less than one-week time. Side effects of
radiation have dramatically reduced and now radiation therapy is more
acceptable to the patients. Radiation therapy is the standard of care in early
head & neck cancer, cervical cancer and an important component of organ
preserving procedures such as breast conservation. After surgery, majority of
advanced cancers are treated with radiation therapy. Stereotactic radiosurgery
is now the alternative to surgery in deep-seated 'difficult to do surgery'
cases. There are numerous randomized studies with level-I evidences showing
survival (mainly loco-regional control and also over all survival) benefit of
radiation therapy in brain tumours, head & neck cancers, breast cancer,
cervical cancer and other cancers.
Radiation therapy is a
cost-effective option in management of metastatic diseases and palliative
situations such as bone metastasis and brain metastasis. In developing
countries like India with resource constraints radiation therapy should be used
in most of the clinical situations, especially in palliative and management of
pain.
In future, proton beam therapy,
intra-operative radiation therapy and shorter course of radiation therapy
(fractionated radiosurgery) will be the one of the main ammonium to fight
against cancer. However, there are still many challenges in radiation oncology
that needs to be addressed.
More than 70% of cancers need
radiation therapy at some point of time. In 2020, India will have one of the
largest numbers of cancer patients in the world and there will be two times
than the present cancer burden. Unfortunately, there are in a severe scarcity
of radiation therapy facilities in developing countries like India. At present
situation, with available radiation facility in India only 30% of patients who
require radiation treatment can avail radiation therapy. Majority of the
patients need to travel far from their native place for treatment, only a small
proportion of patients who need treatment receive radiation therapy, there is
lack of awareness and cost of the treatment (facility) is also an issue. There
is a need for more number of cancer facility including radiation therapy
machines in different small cities and towns in India.
The author of this article is Dr.Debnarayan Dutta, consultant, Apollo Speciality Hospital
For More information feel free to blog your comments or write to lakshmipriya_b@apollohospitals.com or I can be reached @9940675877
