Comments on National guidelines for diagnosis and treatment of gastric cancer 2022 in China (English version)

Jiahui Chen ,Zhaode Bu ,Jiafu Ji

1Department of Gastric Surgery,the Cancer Hospital of the University of Chinese Academy of Sciences (Zhejiang Cancer Hospital),Institute of Basic Medicine and Cancer (IBMC),Chinese Academy of Sciences,Hangzhou 310022,China;2 Key Laboratory of Prevention,Diagnosis and Therapy of Upper Gastrointestinal Cancer of Zhejiang Province,Hangzhou 310022,China;3Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing),Center of Gastrointestinal Surgery,Peking University Cancer Hospital＆Institute,Beijing 100142,China

Gastric cancer is one of the most common malignancies in China.According to the latest statistics in 2020,the incidence and mortality of gastric cancer all rank the third among all cancers,which have brought a huge burden to people’s health and social economy.Besides the high morbidity and mortality,the low early diagnosis rate is another dilemma of gastric cancer in China.Early gastric cancer accounts for only 20% of new gastric cancer cases in China.Most cases are already in the advanced stage when discovered,and the overall 5-year survival rate is less than 50% (1,2).Over the past decades,China has made great progress in the prevention and treatment of gastric cancer,but it is still a relatively prominent health problem.

There are significant geographic differences in gastric cancer.Globally,the incidence and mortality of gastric cancer are the highest in East Asia,while lower in North America and Northern Europe.In China,the areas with high incidence of gastric cancer are mainly distributed in the eastern coastal areas and the middle and upper reaches of the Yellow River.The differences in genetics,diet,and hygiene conditions are important factors for the regional distribution differences of gastric cancer.In the past few decades,the National Comprehensive Cancer Network(NCCN) guidelines on gastric cancer and Japanese gastric cancer treatment guidelines and classification have been important basis for Chinese doctors and researchers in the diagnosis and treatment of gastric cancer.However,simply copying the experience of the United States and Japan is not entirely suitable for China’s situation.Under this circumstance,the Chinese Ministry of Health compiled the first edition of “Guidelines for Diagnosis and Treatment of Gastric Cancer in China” in 2011 and has updated several editions.It has played an important role in the diagnosis and treatment of gastric cancer in China over the past decade.To further improve the diagnosis and treatment of gastric cancer,the National Health Commission of the People’s Republic of China updated the 2022 version of the Chinese guidelines for diagnosis and treatment of gastric cancer based on the 2018 version guideline (3,4).

In order to meet the current needs for diagnosis and treatment of gastric cancer in China,the 2022 version guideline follows the international frontier and has been updated both in diagnosis and treatment.With the promotion of gastric cancer screening by the government,the proportion of early gastric cancer is increasing year by year.In order to further reduce the false negative rate of diagnosis and prevent more patients from being missed,the new guideline reduces the original PG I/PG II diagnostic criteria from 7.0 to 3.0 so as to indicate the existence of gastric cancer at an earlier stage.However,the new guidelines have become more cautious about the absolute indications for endoscopic treatment of early gastric cancer.The absolute indications for cT1a tumors larger than 2 cm without ulceration or cT1a tumors smaller than 3 cm with ulceration specified in old version of guidelines have changed from absolute indications to relative indications in the new guidelines.

Surgery is still the cornerstone of gastric cancer treatment.With the publication of results of a number of clinical studies related to laparoscopic surgery for gastric cancer in recent years,the new guideline expands indications for laparoscopic surgery.The 2018 version guideline only recommended laparoscopic surgery as a routine treatment for patients with clinical stage I,while in the 2022 version guideline,it was expanded to include those with depth of invasion within T2.In addition,the new guideline also encourages researchers to further explore the application of laparoscopic surgery in the treatment of gastric cancer.In the drug treatment of gastric cancer,the success of Checkmate 649 (5) and Attraction-2(6) studies has established an important position of immunotherapy in the drug treatment of gastric cancer.Furthermore,with the introduction of a new generation of chemotherapy drugs such as nab-paclitaxel into the clinic,the incidence of drug allergy has been effectively controlled.Unfortunately,the new guidelines do not include immunotherapy in the first-line adjuvant therapy for gastric cancer.Likewise,emerging antibody-drug conjugates,such as DS-8201,have also not been recommended.We look forward to more clinical studies in the future to continue to promote the precise treatment of gastric cancer.In terms of palliative care,for patients with advanced gastric cancer in good physical condition,the new guideline provides multiple 3-drug combination regimens.For patients with poor performance status or advanced age,the new guidelines recommend single-agent chemotherapy with oral fluorouracils or taxanes.For radiotherapy,the new guidelines emphasize that preoperative concurrent chemoradiotherapy can improve the success rate of conversion therapy.By irradiating the location of the primary tumor and the area of lymphatic drainage,the risk of local and regional recurrence can be reduced.

In all,we are gratified to see that in the past few years,great progress has been made in both surgical treatment of gastric cancer and therapeutic drugs.Researchers,physicians,and pathologists around the world have contributed tremendously to the development of this guideline.However,the pathogenesis of gastric cancer is extremely complex.Compared with other malignant tumors,the high heterogeneity of gastric cancer has brought great challenges to the treatment and research.Our understanding of gastric cancer is gradually accumulating.Although there are still many controversies,regrets and unknowns in this guideline,we sincerely hope that the controversies and uncertainties contained in the 2022 guideline can guide future gastric cancer research and further improve guidelines,ultimately benefiting gastric cancer patients in China.

Acknowledgements

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Footnote

Conflicts of Interest: The authors have no conflicts of interest to declare.