Three digestive cancers that can be cured if detected early:

1. Stomach cancer:
   Stomach cancer can develop slowly and may not show clear symptoms in the early stages, so early detection is crucial. If detected at an early stage, the chances of a cure are high through surgery to remove the affected part of the stomach, or a combination of surgery, chemotherapy, and radiation therapy. When the cancer has spread, treatment becomes more complicated.

2. Colorectal cancer:
   Colorectal cancer often develops from benign polyps in the colon and can be easily detected through regular screening, such as colonoscopy. If detected early, the disease can be effectively treated with surgery to remove the tumor or the affected part of the colon, combined with chemotherapy or radiation therapy to prevent recurrence.

3. Liver cancer:
   Although liver cancer is one of the most dangerous cancers, it can be cured if detected early, especially in patients at high risk, such as those with chronic hepatitis (HBV, HCV) or cirrhosis. Early detection can allow for timely intervention with surgery to remove the tumor or liver transplantation, increasing the chance of survival for the patient.

Regular screenings and routine health check-ups are crucial for early detection of signs of digestive cancers, improving the chances of successful treatment.