Cancer: Scenario and Relationship of Different Geographical
Areas of the Globe with Special Reference to North East-India
Jagannath Dev Sharma1, Manoj Kalit1*, Tulika Nirmolia2, Sidhartha Protim
Saikia2, Arpita Sharma1, Debanjana Barman1
Background: Cancer is becoming the most important public health burden around the globe. As per the
GLOBOCAN 2008 estimates, about 12.7 million cancer cases and 7.6 million cancer deaths were estimated
to have occurred in 2008. The burden of cancer cases for India in the year 2020 is calculated to be 1,148,757
(male 534,353; female 614,404) compared to 979,786 in 2010. The pattern of cancer incidence is varying among
geographical regions, esophageal cancer for example being high in China, lung cancer in USA, and gallbladder
cancer in Chile. The question remains why? Is it due to the diversity in genome pool, food habits, risk factor
association and role of genetic susceptibility or some other factors associated with it? In India, the North East
(NE)-India region is seeing a marked increase in cancer incidence and deaths, with a very different cancer
incidence pattern compared to mainland India. The genome pool of the region is also quite distinct from the rest
of India. Northeastern tribes are quite distinct from other groups; they are more closely related to East Asians
than to other Indians. In this paper an attempt was made to see whether there is any similarity among the pattern
of cancer incidence cases for different sites of NE-India region to South or East-Asia. Materials and Methods:
Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), Pearson Correlation coefficient test
was assessed to evaluate the linkage of North-East India region to other regions. A p value <0.05 was considered
as statistically significant. Results: The results clearly shows that there are similarities in occurrence of cancer
incidence patterns for various cancer sites of NE-India with South and East-Asian regions, which may lead to
the conclusion that there might be a genetic linkage between these regions.
Keywords: Cancer - oesophagus - lung - stomach - hypopharynx - nasopharynx - TRC
Asian Pac J Cancer Prev, 15 (8), 3721-3729