The Relationship between Annual Airborne Pollen Levels and Occurrence of All Cancers, and Lung, Stomach, Colorectal, Pancreatic and Breast Cancers: A Retrospective Study from the National Registry Database of Cancer Incidence in Japan, 1975-2015

Abstract

Suppression of risk factors including smoking, overdrinking and infections by human papilloma and hepatitis B and C viruses has been recommended for cancer prevention; however, identification of other environmental risk factors has not been enough. Besides the 2003 report that Kawasaki disease may be triggered by pollen exposure, 40 Japanese specific intractable diseases have recently been reported as "pollen diseases," also potentially triggered by pollen exposure．Various human organs are affected by pollen exposure, leading to systemic vasculitis; autoimmune connective tissue diseases, inflammatory bowel diseases and intractable neuromuscular and bone diseases, suggesting the common effects of pollen exposure on fundamental functions of vital metabolism. In this context, cancer and malignant tumors may be another group of intractable diseases triggered by epigenetic pollen exposure. Thus, this study compared the number of newly registered patients with 24 types of cancer and airborne pollen levels measured from 1975 to 2015. We searched for statistical correlations with Bonferroni correction between the annual number of newly registered patients for all cancers or for each of lung, stomach, colorectal, pancreatic and breast cancers in the patient-registry year "x", and annual airborne pollen levels measured in the same year as "x", or 1-7 years prior to the year "x". The number of newly registered patients for lung, and pancreatic cancers in the patient-registry year "x" was highly correlated with airborne pollen levels measured 2 years prior to "x". That for breast cancer was correlated with pollen levels measured 2 and 5 years prior to "x". To our knowledge, this is the first rapid communication of the association between pollen levels and cancer incidence.

Keywords: Kawasaki disease; airborne pollen exposure; breast cancer; cancer incidence; lung cancer; pancreatic cancer; pollen diseases; specific intractable diseases.

Figure 1

The current number of Japanese males and females (presently registered patients) registered for all cancers at the year diagnosed, its year-on-year increase (newly registered patients), and the amount of air borne pollen scatter in 3 areas during the period from 1975 to 2015. The line graphs for all cancers representing numbers of presently and newly registered patients in each year, as well as the amount of pollen scattered in Bunkyo-City area of Tokyo, the whole Tokyo Metropolitan area and Sagamihara City during the period from 1975 to 2015. Orange arrows indicate phasic increments of newly registered patients occurring six years after phasic increments of airborne pollen scatter. Numbers of patients are shown on the left axis whose scales consist of red numbers for newly registered patients and black numbers for presently registered patients. Pollen numbers in counts/cm² are shown on the right axis.

Figure 2

The current number of Japanese males and females (presently registered patients) registered for cancer of the lung and the trachea at the year diagnosed, its year-on-year increase (newly registered patients), and the amount of air borne pollen scatter in 3 areas during the period from 1975 to 2015. The line graphs for males and females with cancer of the lung and the trachea representing numbers of presently and newly registered patients in each year, as well as the amount of pollen scattered during the period from 1975 to 2015. Violet arrows indicate phasic increments of newly registered patients occurring two years after phasic increments of airborne pollen scatter.

Figure 3

The current number of Japanese males (presently registered patients) registered for cancer of the lung and the trachea at the year diagnosed, its year-on-year increase (newly registered patients), and the amount of air borne pollen scatter in 3 areas during the period from 1975 to 2015. The line graphs for males with cancer of the lung and the trachea representing numbers of presently and newly registered patients in each year, as well as the amount of pollen scattered during the period from 1975 to 2015. Violet arrows indicate phasic increments of newly registered patients occurring two years after phasic increments of airborne pollen scatter.

Figure 4

The current number of Japanese females (presently registered patients) registered for cancer of the lung and the trachea at the year diagnosed, its year-on-year increase (newly registered patients), and the amount of air borne pollen scatter in 3 areas during the period from 1975 to 2015. The line graphs for females with cancer of the lung and the trachea representing numbers of presently and newly registered patients in each year, as well as the amount of pollen scattered during the period from 1975 to 2015. Violet or orange arrows indicate phasic increments of newly registered patients occurring two or six years after phasic increments of airborne pollen scatter, respectively.

Figure 5

The current number of Japanese males and females (presently registered patients) registered for stomach cancer at the year diagnosed, its year-on-year increase (newly registered patients), and the amount of air borne pollen scatter in 3 areas during the period from 1975 to 2015. The line graphs for males and females with stomach cancer representing numbers of presently and newly registered patients in each year, as well as the amount of pollen scattered during the period from 1975 to 2015. No relationship was noted between phasic increments of newly registered patients and phasic increments of airborne pollen scatter.

Figure 6

The current number of Japanese males and females (presently registered patients) registered for colorectal cancer at the year diagnosed, its year-on-year increase (newly registered patients), and the amount of air borne pollen scatter in 3 areas during the period from 1975 to 2015. The line graphs for males and females with colorectal cancer representing numbers of presently and newly registered patients in each year, as well as the amount of pollen scattered during the period from 1975 to 2015. No relationship was noted between phasic increments of newly registered patients and phasic increments of airborne pollen scatter.

Figure 7

The current number of Japanese males and females (presently registered patients) registered for pancreatic cancer at the year diagnosed, its year-on-year increase (newly registered patients), and the amount of air borne pollen scatter in 3 areas during the period from 1975 to 2015. The line graphs for males and females with pancreas cancer representing numbers of presently and newly registered patients in each year, as well as the amount of pollen scattered during the period from 1975 to 2015. Violet or orange arrows indicate phasic increments of newly registered patients occurring two or seven years after phasic increments of airborne pollen scatter, respectively.

Figure 8

The current number of Japanese females (presently registered patients) registered for breast cancer at the year diagnosed, its year-on-year increase (newly registered patients) and the amount of air borne pollen scatter in 3 areas during the period from 1975 to 2015. The line graphs for females with breast cancer representing numbers of presently and newly registered patients in each year, as well as the amount of pollen scattered during the period from 1975 to 2015. Violet or orange arrows indicate phasic increments of newly registered patients occurring two or five years after phasic increments of airborne pollen scatter, respectively.