Very recently, the World Health Organization and International Agency for Research on Cancer have produced findings by over 800 different studies that show that there is a link between processed meats (including bacon) and cancer. Eating processed meats in large quantities have been linked to increasing your risk for colon and rectal cancer. 10 of these studies suggest that 50 grams of processed meat daily (approximately 2 slices of bacon) can increase your risk for colorectal cancer by about 18%. Some studies suggest an association between processed meats and stomach cancer, but this has not yet been proven or disproved.
Processed meat has been classified as a Group 1 carcinogen, meaning that there is a proven link between processed meat and cancer. According to Global Burden of Disease Project, approximately 34,000 cancer deaths per year may be attributed to high consumption of processed meat.
So yes, in large daily quantities, bacon can cause cancer. However, WHO notes the benefits of having meat in your diet and state that you don't necessarily need to entirely cut out bacon or other processed meat from your diet. Rather, you should monitor and moderate your intake to decrease your risk for colorectal cancer.