Pathogenesis and prevention of postoperative recurrence and metastasis of non-small cell lung cancer based on the "combination of latent and new pathogens causes disease" theory

The risk of recurrence and metastasis after surgery for non-small cell lung cancer remains is a major clinical challenge. Traditional Chinese medicine shows therapeutic potential in preventing recurrence and metastasis as well as improving the quality of life, particularly for patients who do not require adjuvant therapy postoperatively or those who have poor tolerance to its adverse effects. This study explores the pathogenesis of postoperative recurrence and metastasis in non-small cell lung cancer based on the theory of "combination of latent and new pathogens causes disease" in the Inner Canon of Yellow Emperor. It posits that new and latent pathogens combine, resulting in recurrence and metastasis. After non-small cell lung cancer surgery, phlegm, stasis, and cancer toxins remain in the body as latent pathogens. New pathogenic factors, including the six external evils and internal damage caused by emotional disturbance, can activate these latent pathogens by disrupting qi movement or weakening the body′s foundation by depleting healthy qi. Consequently, the treatment principle is centered on "clearing the latent pathogen, restoring healthy qi, and preventing the new pathogen." For patients with syndromes characterized by cancer toxins obstructing the lung and intermingled phlegm and blood stasis, the therapeutic strategy aims to dissipate phlegm, eliminate blood stasis, detoxify, and have anticancer effects. Prescriptions are modified Erchen Decoction and Suzi Jiangqi Decoction, with a concerted application of herbs that remove toxicity. For patients with healthy qi deficiency after surgery, the strategy emphasizes invigorating the spleen and kidney, benefiting qi, and nourishing yin. Modified Sijunzi Decoction and Qidong Bufei Decoction prescriptions are used to benefit qi. This approach involves regulating qi movement and maintaining health in accordance with nature to prevent the emergence of new pathogenic factors. Non-pharmacological therapies, including emotional regulation and dietary modification, are used to prevent recurrence and metastasis. Guided by the theory of "combination of latent and new pathogens causes disease," this study explores the pathogenesis of postoperative recurrence and metastasis in non-small cell lung cancer. Integrating our team′s clinical experience, we propose preventive and therapeutic strategies to provide novel insights for the prevention and treatment of postoperative recurrence and metastasis of non-small cell lung cancer using traditional Chinese medicine.