Modes of spread and metastasis of esophageal cancer. In the early to mid-stages, the spread is mainly intramural, as the esophagus lacks a serosal layer, making it easy to directly invade adjacent organs. Lymphatic metastasis is also a major route of spread for esophageal cancer. In advanced stages, the cancer metastasizes through the bloodstream to the liver, lungs, kidneys, and even bones. In cases of bone metastasis, treatment options such as chemotherapy, radiotherapy, and anti-bone metastasis treatment can be chosen based on the patient's general condition. If the patient experiences significant pain, pain relief medication can be chosen according to the three-step ladder for cancer pain treatment to alleviate symptoms.