Rajesh Dikshit

Bio: Rajesh Dikshit is an academic researcher from Homi Bhabha National Institute. The author has contributed to research in topics: Population & Cancer. The author has an hindex of 32, co-authored 91 publications receiving 26879 citations. Previous affiliations of Rajesh Dikshit include Tata Memorial Hospital & International Agency for Research on Cancer.

Prevalence of human papillomavirus types in head and neck cancer sub-sites in the Indian population

Abstract: Although a subset of head and neck cancers (HNC) has been associated worldwide with mucosal high-risk human papillomaviruses (HPV), information on the prevalence of HPV-positive HNC in India is limited. In this study, we examined the prevalence of 21 subtypes of HPV in sub-sites of HNC (n = 175) in the western region of India. Type-specific multiplex genotyping assay was conducted at the Centre for Cancer Epidemiology, Tata Memorial Centre, to determine the prevalence of HPV subtypes. The HPV prevalence was observed to be 28.43%, 41.67%, 38.89% and 15.79% in the oral cavity, oropharynx, hypopharynx and larynx tumour tissues, respectively. The HPV 16 genotype was most common in all HNC tumour tissues (30.29%), followed by HPV 58 (0.57%).

Mortality Associated with Ambient PM2.5 Exposure in India: Results from the Million Death Study

Abstract: Background: Studies on the extent to which long-term exposure to ambient particulate matter (PM) with aerodynamic diameter ≤2.5μm (PM2.5) contributes to adult mortality in India are few, despite over 99% of Indians being exposed to levels that the World Health Organization (WHO) considers unsafe. Objective: We conducted a retrospective cohort study within the Million Death Study (MDS) to provide the first-ever quantification of national mortality from exposure to PM2.5 in India from 1999 to 2014. Methods: We calculated relative risks (RRs) by linking a total of ten 3-y intervals of satellite-based estimated PM2.5 exposure to deaths 3 to 5 y later in over 7,400 small villages or urban blocks covering a total population of 6.8 million. We applied using a model-based geostatistical model, adjusted for individual age, sex, and year of death; smoking prevalence, rural/urban residency, area-level female illiteracy, languages, and spatial clustering and unit-level variation. Results: PM2.5 exposure levels increased from 1999 to 2014, particularly in central and eastern India. Among 212,573 deaths at ages 15–69 y, after spatial adjustment, we found a significant RR of 1.09 [95% credible interval (CI): 1.04, 1.14] for stroke deaths per 10-μg/m3 increase in PM2.5 exposure, but no significant excess for deaths from chronic respiratory disease and ischemic heart disease (IHD), all nonaccidental causes, and total mortality (after excluding stroke). Spatial adjustment attenuated the RRs for chronic respiratory disease and IHD but raised those for stroke. The RRs were consistent in various sensitivity analyses with spatial adjustment, including stratifying by levels of solid fuel exposure, by sex, and by age group, addition of climatic variables, and in supplementary case–control analyses using injury deaths as controls. Discussion: Direct epidemiological measurements, despite inherent limitations, yielded associations between mortality and long-term PM2.5 inconsistent with those reported in earlier models used by the WHO to derive estimates of PM2.5 mortality in India. The modest RRs in our study are consistent with near or null mortality effects. They suggest suitable caution in estimating deaths from PM2.5 exposure based on MDS results and even more caution in extrapolating model-based associations of risk derived mostly from high-income countries to India. https://doi.org/10.1289/EHP9538

Do cervical cancer data justify human papillomavirus vaccination in India? Epidemiological data sources and comprehensiveness

Abstract: In their paper, Mattheij et al.1 propose that current epidemiological data do not justify human papillomavirus (HPV) vaccination in India. They state ‘current data on HPV type and cervical cancer incidence do not support [the] claim that India has a large burden of cervical cancer’. As the source of many of these data, we strongly contest this viewpoint. Our GLOBOCAN 2008 estimates of the burden of cervical cancer in India indicate that the incidence rates are substantially in excess of those observed in, for example, the UK, where the authors are based and where there is a school-based vaccination programme (age standardized rates of 27 and 7 per 100,000, respectively).2 The national estimates for India have a complex derivation due to the need to adequately balance rural/urban populations in different geographical regions, but the methods are clear and reproducible.2 Cervical cancer is the most common or the second most common female cancer in data from the seven highest-quality Indian cancer registries.3 Our recent nationally representative mortality study based on verbal autopsies showed that, in 2010, cervical cancer was the leading fatal cancer among women aged 30–69 years in both rural and urban areas.4 Overall we estimate that over a quarter of the world's cervical cancer cases and over a third of the cervical cancer deaths occur in India.2 While we agree with Mattheij et al. that incidence rates are declining over time in some urban regions,3 this is mainly due to the impact of multiple social factors (family planning, education and socioeconomic improvement)5,6 combined with the developing programmes for screening and early detection.7 What is known about HPV and high-risk HPV prevalence in India would indicate that, rates are at the higher end of a global scale (exactly as for cervical cancer incidence) and, unlike in many other populations, tend to stay high in middle-age women.8 More than elsewhere, high-risk HPV types 16 and 18 predominate in invasive cancer9 indicating current vaccines would be very effective. Cancer surveillance in India is incomplete and faces uncertainties in estimation. However, there are a large number of cancer registries and more data are available than for many other countries at a similar developmental level. The surveillance data that we have, indicate quite clearly that HPV infection and associated cervical cancer risk in India is a substantive burden and clear health priority which can be addressed now by a combination of screening and vaccination.

Global cancer statistics

Abstract: The global burden of cancer continues to increase largely because of the aging and growth of the world population alongside an increasing adoption of cancer-causing behaviors, particularly smoking, in economically developing countries. Based on the GLOBOCAN 2008 estimates, about 12.7 million cancer cases and 7.6 million cancer deaths are estimated to have occurred in 2008; of these, 56% of the cases and 64% of the deaths occurred in the economically developing world. Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer death among females, accounting for 23% of the total cancer cases and 14% of the cancer deaths. Lung cancer is the leading cancer site in males, comprising 17% of the total new cancer cases and 23% of the total cancer deaths. Breast cancer is now also the leading cause of cancer death among females in economically developing countries, a shift from the previous decade during which the most common cause of cancer death was cervical cancer. Further, the mortality burden for lung cancer among females in developing countries is as high as the burden for cervical cancer, with each accounting for 11% of the total female cancer deaths. Although overall cancer incidence rates in the developing world are half those seen in the developed world in both sexes, the overall cancer mortality rates are generally similar. Cancer survival tends to be poorer in developing countries, most likely because of a combination of a late stage at diagnosis and limited access to timely and standard treatment. A substantial proportion of the worldwide burden of cancer could be prevented through the application of existing cancer control knowledge and by implementing programs for tobacco control, vaccination (for liver and cervical cancers), and early detection and treatment, as well as public health campaigns promoting physical activity and a healthier dietary intake. Clinicians, public health professionals, and policy makers can play an active role in accelerating the application of such interventions globally.

Global cancer statistics, 2012

Abstract: Cancer constitutes an enormous burden on society in more and less economically developed countries alike. The occurrence of cancer is increasing because of the growth and aging of the population, as well as an increasing prevalence of established risk factors such as smoking, overweight, physical inactivity, and changing reproductive patterns associated with urbanization and economic development. Based on GLOBOCAN estimates, about 14.1 million new cancer cases and 8.2 million deaths occurred in 2012 worldwide. Over the years, the burden has shifted to less developed countries, which currently account for about 57% of cases and 65% of cancer deaths worldwide. Lung cancer is the leading cause of cancer death among males in both more and less developed countries, and has surpassed breast cancer as the leading cause of cancer death among females in more developed countries; breast cancer remains the leading cause of cancer death among females in less developed countries. Other leading causes of cancer death in more developed countries include colorectal cancer among males and females and prostate cancer among males. In less developed countries, liver and stomach cancer among males and cervical cancer among females are also leading causes of cancer death. Although incidence rates for all cancers combined are nearly twice as high in more developed than in less developed countries in both males and females, mortality rates are only 8% to 15% higher in more developed countries. This disparity reflects regional differences in the mix of cancers, which is affected by risk factors and detection practices, and/or the availability of treatment. Risk factors associated with the leading causes of cancer death include tobacco use (lung, colorectal, stomach, and liver cancer), overweight/obesity and physical inactivity (breast and colorectal cancer), and infection (liver, stomach, and cervical cancer). A substantial portion of cancer cases and deaths could be prevented by broadly applying effective prevention measures, such as tobacco control, vaccination, and the use of early detection tests.

Estimates of worldwide burden of cancer in 2008: GLOBOCAN 2008.

Abstract: Estimates of the worldwide incidence and mortality from 27 cancers in 2008 have been prepared for 182 countries as part of the GLOBOCAN series published by the International Agency for Research on Cancer. In this article, we present the results for 20 world regions, summarizing the global patterns for the eight most common cancers. Overall, an estimated 12.7 million new cancer cases and 7.6 million cancer deaths occur in 2008, with 56% of new cancer cases and 63% of the cancer deaths occurring in the less developed regions of the world. The most commonly diagnosed cancers worldwide are lung (1.61 million, 12.7% of the total), breast (1.38 million, 10.9%) and colorectal cancers (1.23 million, 9.7%). The most common causes of cancer death are lung cancer (1.38 million, 18.2% of the total), stomach cancer (738,000 deaths, 9.7%) and liver cancer (696,000 deaths, 9.2%). Cancer is neither rare anywhere in the world, nor mainly confined to high-resource countries. Striking differences in the patterns of cancer from region to region are observed.

Estimating the global cancer incidence and mortality in 2018: GLOBOCAN sources and methods

Abstract: Estimates of the worldwide incidence and mortality from 36 cancers and for all cancers combined for the year 2018 are now available in the GLOBOCAN 2018 database, compiled and disseminated by the International Agency for Research on Cancer (IARC). This paper reviews the sources and methods used in compiling the cancer statistics in 185 countries. The validity of the national estimates depends upon the representativeness of the source information, and to take into account possible sources of bias, uncertainty intervals are now provided for the estimated sex- and site-specific all-ages number of new cancer cases and cancer deaths. We briefly describe the key results globally and by world region. There were an estimated 18.1 million (95% UI: 17.5-18.7 million) new cases of cancer (17 million excluding non-melanoma skin cancer) and 9.6 million (95% UI: 9.3-9.8 million) deaths from cancer (9.5 million excluding non-melanoma skin cancer) worldwide in 2018.