Professor Zhang Xiaotian | CSCO Gastric Cancer Diagnosis and Treatment Guidelines 2021: An updated interpretation of non-metastatic gastric cancer

The 2021 CSCO Guide Conference kicked off in Beijing on April 23 with a combination of online and offline methods.

In the gastrointestinal tumor special session on the morning of the 24th, Professor Zhang Xiaotian from Peking University Cancer Hospital interpreted the updated part of the non-metastatic gastric cancer in the 2021 version of the CSCO gastric cancer diagnosis and treatment guidelines.

Non-metastatic gastric cancer can be divided into resectable gastric cancer, potentially resectable gastric cancer and unresectable gastric cancer.

 1.
Imaging endoscopic diagnosis of gastric cancer "replacement" recommends abdominal MRI as a means of further examination when CT suspects liver metastasis.
It is recommended to use hepatocyte-specific contrast agents for those with conditions, which can improve the sensitivity of liver metastasis diagnosis.

" is "clinical or CT" When liver metastasis is suspected, it is recommended to choose liver MRI plain scan+enhanced examination, according to clinical needs, hepatocyte-specific contrast agent can be used"; add "the curative effect evaluation of immunotherapy can refer to iRECIST standard"; replace "imaging functional imaging parameters" as "Imaging volume measurement and functional imaging parameters"; in terms of pathological diagnosis, new pathological diagnosis specifications for specimens after EMR/ESD have been added.

 2.
Comprehensive treatment of resectable gastric cancer (1) The overall treatment strategy is based on the results of the RESOLVE study.
For patients with stage III non-esophagogastric junction cancer and suitable for surgery, neoadjuvant chemotherapy + gastrectomy D2 + adjuvant chemotherapy, recommended by level II (Type 1B evidence) is promoted to level I recommendation (Type 1A evidence).

 Added notes: marking operations for early gastric cancer CLASS02, advanced gastric cancer KLASS-02, robotic surgery, and laparoscopic exploration.

(2) Neoadjuvant therapy is based on the RESOLVE study.
Neoadjuvant chemotherapy SOX (3 cycles of SOX before operation, 5 cycles of SOX and 3 cycles of S-1 monotherapy) was upgraded from level II recommendation (type 1B evidence) to level I recommendation (Class 1A evidence).For stage III non-esophageal gastric junction cancer, delete the ECF (epirubicin + cisplatin + 5-fluorouracil) and its improvement in the grade III recommendation.

 For stage III esophagogastric junction cancer, the newly added FLOT4 (docetaxel + oxaliplatin + leucovorin + 5-fluorouracil) regimen is a level II recommendation (class 1B evidence).

Added note: For perioperative chemotherapy of advanced gastric cancer, add "HER2-positive gastric cancer is a special type of gastric cancer.
At present, there are also many anti-HER2 treatments explored in perioperative treatment, including two-drug or three-drug chemotherapy, combined Anti-HER2 monoclonal antibody or double antibody has shown initial results, but it has not yet become a standard treatment strategy.

” (3) Postoperative adjuvant treatment For patients with stage III, delete the postoperative adjuvant chemoradiation and chemotherapy in the level III recommendation: DT45~50.
4Gy (at the same time) Fluorouracil).

 3.
Comprehensive treatment of unresectable gastric cancer For unresectable, non-metastatic gastric cancer, conversion therapy is required.

The new version of the guidelines adds a new note to this: For patients with unresectable tumors and generally in good condition, if the tumors are still limited, the radiotherapist assesses those who are feasible for radiotherapy and recommends concurrent radiotherapy and chemotherapy.

Studies have confirmed that concurrent chemoradiation is superior to chemotherapy alone or radiotherapy alone in terms of tumor downgrading rate and pathological remission rate.

If the tumor shrinks well after radiotherapy and chemotherapy, reassess the possibility of surgery and strive for radical resection.

Some literature reports that for patients with locally advanced gastric cancer who can tolerate surgery and have good general conditions, either radical or palliative resection can bring survival benefits.

Retrospective studies have shown that even for patients who cannot be surgically removed, chemotherapy and radiotherapy have a survival benefit over chemotherapy alone.

 Radiotherapy radiation field design: For patients with the possibility of surgery, in addition to the visible tumors (primary, metastatic tumors or metastatic lymph nodes, etc.
) determined by pre-treatment imaging must be included, it can be appropriately expanded to include high-risk lymph node drainage areas.

Radiotherapy dose: DT45~50.
4Gy, after evaluating the curative effect, it is decided to operate or continue systemic treatment.

For patients who are expected to be unresectable, the dose of radical radiotherapy: DT50-60Gy.

Those who are frail and have extensive tumors do not consider surgery.
It is recommended that only visible tumors be included, and preventive irradiation of lymph node areas is not performed.

Palliative radiotherapy dose: DT30~40Gy/10~20 times.

The specific scope and dose of radiotherapy are considered based on the general condition of the patient, the size of the irradiation field, the expected survival period, and the possible radiation damage to normal tissues and organs.

 Finally, Professor Zhang Xiaotian pointed out that the progress in the treatment of non-metastatic gastric cancer mainly depends on the advancement of advanced gastric cancer drug treatment and the advancement of perioperative precision clinical staging.

In this way, we can focus on surgery to prolong and improve the survival of patients with non-metastatic gastric cancer.