What you need to know about esophageal cancer: What are the methods and effects of neoadjuvant therapy?

Author: Chen Keneng, Chief Physician, Peking University Cancer Hospital

Reviewer: Yao Shukun, Chief Physician, China-Japan Friendship Hospital

Esophageal cancer is a malignant tumor that occurs in the esophageal epithelium. It is a common disease in our country. The main symptom is difficulty in swallowing, but it is not easy to detect in the early stages. Many patients are already in the late stage when the disease is discovered, which is locally advanced esophageal cancer.

In order to make the surgery more effective, we usually give the patient induction therapy first, which is the so-called neoadjuvant therapy, which is to push the tumor to an earlier stage and reduce the tumor burden.

Adjuvant therapy is relative to surgery. Esophageal cancer is a disease that uses surgery as the main treatment method. Adjuvant therapy includes systemic therapy, which is chemotherapy and local radiotherapy. If it is done before surgery, it is called neoadjuvant therapy, and if it is done after surgery, it is called adjuvant therapy.

1. What are the benefits of neoadjuvant therapy for patients with esophageal cancer?

There are many benefits of neoadjuvant therapy for patients with esophageal cancer.

First, at this time, the patient has not undergone surgery, his physical condition is relatively good, and his ability to tolerate treatment before surgery is relatively strong.

In addition, through neoadjuvant therapy, the tumor can be downstaged, the tumor burden can be reduced, and it can be easily removed.

At the same time, before the operation, the blood circulation around the tumor and the esophagus is good, so the drugs can easily reach the tumor and take effect.

There is another advantage. After using drug treatment before surgery, we can know whether it is effective or not. For those patients who are ineffective after using the drug, we should not use this drug treatment after surgery.

So neoadjuvant therapy has many benefits.

2. If the tumor disappears after radiotherapy and chemotherapy for esophageal cancer, is surgery still necessary?

Theoretically, it is possible that esophageal cancer does not need surgery after radiotherapy and chemotherapy. However, there are several drawbacks, such as the inability to determine whether there is really no tumor.

For example, compared with the lungs, the esophagus is a hollow organ, and the judgment of hollow organs is very inaccurate.

Lung cancer is very clear. The size of the tumor is related to the prognosis. The smaller the tumor, the better the prognosis. Conversely, the larger the tumor, the worse the prognosis. Lymph nodes are also very clear and easy to biopsy. In imaging, if the short diameter of a lymph node exceeds 1 cm, we suspect that it has metastasized. Then we take a biopsy under ultrasound guidance through a bronchoscope or esophagoscopy. We can take out the lymph node and take a piece of tissue, and we can distinguish it very clearly.

But esophageal cancer is different. For example, ultrasound gastroscopy, CT, MRI, PET/CT, etc., these tests have only a certain sensitivity and accuracy, and are not 100% accurate. So after the preoperative neoadjuvant chemoradiotherapy, the patient feels that his symptoms are completely relieved, and the examination also finds that the tumor has disappeared, but in fact, there is a high possibility that the tumor still exists, but we cannot find it through the existing technical means.

So after neoadjuvant chemoradiotherapy for esophageal cancer, if the tumor disappears, should surgery be performed? At present, it is still recommended that patients undergo surgery.

Figure 1 Original copyright image, no permission to reprint

For some patients, the tumors are truly gone after induction therapy. These patients do not need surgery, but the proportion is very small and we cannot tell the difference clearly yet.

3. How long does it usually take for esophageal cancer patients to undergo surgery after neoadjuvant chemoradiotherapy?

It will take at least three weeks. How is the three weeks determined?

We all know that cells have a certain cycle. Especially for chemotherapy, after three cycles of chemotherapy, the side effects will be alleviated or basically disappear.

After radiotherapy, the time is a little longer, so after the simultaneous treatment of chemotherapy and radiotherapy, surgery will be performed about 6-8 weeks later.

At this time, the tumor has shrunk but has not grown back. At the same time, the patient's symptoms have been relieved and the toxic side effects have disappeared. In addition, at this time, the patient's tolerance, physical strength, and cardiopulmonary function are better, so it is generally more appropriate to perform surgery after 6-8 weeks.

Figure 2 Original copyright image, no permission to reprint

Of course, each patient's situation is different. For example, if a patient has a more severe reaction after radiotherapy, such as esophageal pain and radiation pneumonia, the treatment time will be postponed accordingly. Conversely, if the chemotherapy reaction is more severe, the patient's bone marrow suppression has not been alleviated, the white blood cell count is very low, the patient feels obvious fatigue, has poor appetite and digestion, the treatment time will also be postponed accordingly.

In short, the timing of surgery after induction therapy is not only based on theoretical cell cycle judgment, but also depends on the patient's recovery and oncological judgment of tumor growth, remission, and maintenance in order to make a comprehensive judgment.