Colorectal cancer--tuberculosis connection.
Tuberculosis is common in countries with a low incidence of colorectal cancer. A survey was made to determine whether there was any difference in mortality from colorectal cancer in Australia between matched groups with, and without, tuberculous disease. Four hundred consecutively decreased tuberculous patients were compared with a similar number proved not to have contracted any tuberculous infection, and were matched by age, sex, year of death, and socioeconomic ethnic status. There was a statistical significance (P less than 0.01) for colorectal and other gastrointestinal cancers, but not for other cancers. In the non-tuberculous group, there were 21 deaths from colorectal and 24 deaths from other gastrointestinal cancer compared to seven deaths from colorectal and seven from other gastrointestinal cancers in tuberculous patients. Increased immunity against the tubercle bacillus may have played a part in these findings.