Does pancreatic cancer need adjuvant radiotherapy after surgery? Lymphatic metastasis status is the key Background Pancreatic cancer is one of the common malignant tumors of the digestive system and is the fourth leading cause of death. In recent years, the morbidity and mortality of pancreatic cancer are also on the rise. Its malignant degree is high, and local infiltration and systemic metastasis can occur at an early stage. Although surgery is the only definite treatment to achieve long-term disease control, the surgical resection rate is only 15%-20% due to the invasive biological nature of pancreatic cancer, which has an insidious onset and few specific symptoms and signs. Local recurrence and distant metastasis are the main causes of postoperative treatment failure of pancreatic cancer, and if local recurrence and distant metastasis of pancreatic cancer can be improved, its survival prognosis will also be significantly improved. The pancreatic gland is very prone to metastasis because of its thin peritoneum and rich lymphatic content. Lymphatic metastasis is the most common route of metastasis. As one of the most important prognostic factors of pancreatic cancer, lymph node metastasis can significantly affect the local control rate and distant metastasis rate of pancreatic cancer. Patients with positive postoperative lymph nodes have a high rate of recurrence and metastasis and a poor survival prognosis. Therefore, the choice of treatment for these patients is particularly important. Adjuvant radiotherapy, as a local and distant treatment, was once considered to be a good choice for postoperative adjuvant therapy, but the findings of several large-scale prospective clinical trials abroad are inconsistent: some institutions found it to be effective; some institutions found it to be insignificant, and there was no difference even with patients who underwent surgery alone without any postoperative treatment. In the study, a research team led by Professor Yu Xian-F of the Department of Pancreatic Surgery, Fudan University Pancreatic Cancer Institute/Fudan University Cancer Hospital retrospectively analyzed the correlation between lymphatic metastasis status and postoperative adjuvant treatment strategy and prognosis in 280 patients with pancreatic cancer after pancreaticoduodenectomy, and confirmed the therapeutic value of adjuvant radiotherapy in patients with resectable pancreatic cancer, especially those with lymphatic metastasis. The paper was published recently in the International Journal of Pancreatic Cancer. The paper was recently published in Pancreatology, a leading international journal in the field of pancreas. The Institute of Pancreatic Oncology of Fudan University has conducted an in-depth exploration of the therapeutic significance of postoperative adjuvant radiotherapy based on the lymph node status of pancreatic cancer. A retrospective analysis of 280 patients with pancreatic cancer after pancreaticoduodenectomy was performed, of which 128 patients received postoperative adjuvant chemotherapy, 64 received concurrent radiotherapy, and 88 did not receive adjuvant therapy. Analysis of prognostic-related factors showed that patients who received postoperative adjuvant radiotherapy had significantly longer survival compared with surgery alone. Further analysis of patients with intraoperative lymph node metastasis showed that adjuvant radiotherapy was more relevant for patients with positive postoperative lymph nodes in pancreatic cancer. In patients with positive lymph nodes, postoperative adjuvant radiotherapy significantly prolonged overall survival compared with surgery alone. However, in lymph node-negative patients, there was no significant difference in survival prognosis between the two treatment options. In addition, our study confirmed that postoperative adjuvant radiotherapy in lymph node-positive patients can achieve similar results as surgery alone in lymph node-negative patients. Thus, the value of adjuvant radiotherapy in patients with resectable pancreatic cancer is evident; especially in lymph node-positive patients, adjuvant postoperative radiotherapy should be the first choice.