Negating the impact of radiation in development of cancers.

Dear Editor,

Radiation is part of mans’ environment, and people are usually exposed to both natural (viz. cosmic rays, environmental - soil, water, vegetation, etc.) and man-made (viz. medical exposure, occupational exposure, nuclear fall-out, television, mobile, etc.) sources of radiation.[1] In the modern era, radiation is like a double-edged sword, with utilities in fields like medicine, industry, agriculture and research and, at the same time, being a serious potential health hazard if not properly used or contained.[12]

Exposure of humans to radiations beyond the maximal permissible limits has led to a wide range of complications such as acute events (viz. skin burns, dermatitis, acute radiation syndrome, local radiation injuries and blood dyscrasias), chronic events like malignancies (viz. lung cancer, leukemia, thyroid cancer, female breast cancer, basal cell carcinoma, squamous cell carcinoma, melanoma, etc.), birth defects (viz. exposure of pregnant women to radiation during antenatal period) and even death.[12] In addition, a high incidence of psychological distress and psychiatric disorders like posttraumatic stress disorder, anxiety disorders, depression and alcohol use disorder have been observed among the survivors, especially secondary to a nuclear accident.[34] However, the extent of radiation-induced damage is dependent upon parameters like age at the time of exposure, dose of radiation, duration of exposure, type of radiation and the sensitivity of different tissues and organs.[156]

Nevertheless, in most of the settings, the incidence of radiation-induced cancer/complications are still on the rise owing to the presentation of clinical manifestations after a prolonged period of exposure (lag period), poor awareness among the masses about the sources/side-effects of radiation exposure, minimal sensitization of the physicians regarding assessment of radiation exposure, unavailability or poor condition of personal protective equipments in different industries, nonutilization of the protective equipments despite their availability because of ignorance or poor awareness, noncompliance with the recommended environmental standards in different industries, absence of universal implementation of either preplacement examination or periodic medical examination, no guidelines to promote early diagnosis or initiate the process of referral of patients to higher centers, limited access to information about supportive care services and absence of standardized recommendations regarding different aspects of radiation.[1247] These are the key challenges that need to be sorted out for bringing about an improvement in the indicators of cancer.

In order to either prevent or reduce the incidence of radiation-associated cancer, there is an essential need that program managers and radiation experts realize the risk of radiation exposure and then plan evidence-based strategies in collaboration with different stakeholders.[14] This essentially involves ensuring comprehensive risk assessment (viz. based on the specific radiation sources, types of harmful effects that could result, exposure assessment to establish maximum permissible limits and estimation of lifetime risk of cancer),[3] adopting a specific model to empirically evaluate the influence of time since exposure and age at exposure on radiation-induced cancer,[6] implementing preventive strategies (viz. preplacement examination, use of protective equipments or dosimeter, periodic medical examination, compliance with the environmental recommended strategies) in industries or health care establishments,[2] creating awareness among physicians, populations and outreach workers regarding radiation-induced cancer,[2] formulating guidelines to adopt appropriate line of management based on the stage of cancer and patient-related factors,[8] extending support to cancer patients,[7] developing a mechanism to promote medical monitoring and follow-up of populations (viz. persons who developed clinical conditions requiring medical assistance during the emergency and asymptomatic persons known) to facilitate early detection and prompt initiation of treatment,[39] ensuring early management of mental health issues among the victims and their family members,[4] developing a strategic disaster plan to enable preparedness, evacuation and relocation at times of nuclear accidents[34] and building linkages with different international agencies[1] can be tried upon to reduce the incidence of radiation-induced cancers.

To conclude, radiation has been recognized as a key etiological factor in the development of multiple cancers. However, their role in natural history of malignancies can be nullified provided appropriate prevention and control strategies are implemented worldwide.