Lymph Node Dissection Is a Risk Factor for Short-Term Cough after Pulmonary Resection

Cough is a common complication after pulmonary resection. However, the factors associated with cough that develop after pulmonary resection are still controversial. In this study, we used the Simplified Cough Score (SCS) and the Leicester Cough Questionnaire (LCQ) score to investigate potential risk factors for postoperative cough. Between January 2017 and June 2021, we collected the clinical data of 517 patients, the SCS at three days after surgery and the LCQ at two weeks and six weeks after surgery. Then, univariate and multivariate analyses were used to identify the independent risk factors for postoperative cough. The clinical baseline data of the cough group and the non-cough group were similar. However, the cough group had longer operation time and more blood loss. The patients who underwent lobectomy were more likely to develop postoperative cough than the patients who underwent segmentectomy and wedge resection, while the patients who underwent systematic lymph node dissection were more likely to develop postoperative cough than the patients who underwent lymph node sampling and those who did not undergo lymph node resection. When the same lymph node management method was applied, there was no difference in the LCQ scores between the patients who underwent wedge resection, lobectomy and segmentectomy. The lymph node resection method was an independent risk factor for postoperative cough (p < 0.001). Conclusions: Lymph node resection is an independent risk factor for short-term cough after pulmonary resection with video-assisted thoracoscopic surgery, and damage to the vagus nerve and its branches (particularly the pulmonary branches) is a possible cause of short-term cough. The mechanism of postoperative cough remains to be further studied.

676 NECESSITY OF EXTENDED LOWER PARATRACHEAL LYMPH NODE RESECTION DURING ESOPHAGECTOMY FOR CANCER

Objective To evaluate the impact of lower paratracheal lymph node resection on oncological radicality and complication rate during esophagectomy for cancer. Backround The ideal extend of lymphadenectomy (LAD) in esophageal surgery is debated. Until today, there has been no proof for improved survival after standardized paratracheal lymph node resection performing oncological esophagectomy. Methods Lymph nodes from the lower paratracheal station are not standardly resected during 2-field Ivor-Lewis esophagectomy for esophageal cancer. Retrospectively, we identified 200 patients operated in our center for esophageal cancer from January 2017—December 2019. Histopathologically, 143 patients suffered from adenocarcinoma, 53 patients from squamous cell carcinoma, two patients from neuroendocrine carcinoma, and one from melanoma of the esophagus. Patients with and without lower paratracheal LAD were compared to patients regarding demographic data, tumor characteristics, operative details, postoperative complications, tumor recurrence and overall survival. Results 103 of 200 patients received lower paratracheal lymph node resection. On average, six lymph nodes were resected in the paratracheal region with histopathological cancer positivity in two patients. Those two patients suffered from neuroendocrine carcinoma and melanoma, none of the AC or SCC patients were positive. There was no significant difference between both groups regarding age, gender, BMI, or comorbidity. Harvesting of lower paratracheal lymph nodes was associated with less postoperative overall complications (p-value 0,029). Regarding overall survival and recurrence rate no difference could be detected between both groups (p-value 0,168, respectively 0,371). Conclusion The resection of lower paratracheal lymph nodes during esophagectomy seems not mandatory for distal squamous cell carcinoma or adenocarcinoma of the esophagus. It may be necessary in NEC, Melanoma of the esophagus or on demand if suspicious LN are detected in the CT scan. No increase of morbidity was caused by paratracheal dissection.

Tumour draining lymph node-generated CD8 T cells play a role in controlling lung metastases after a primary tumour is removed but not when adjuvant immunotherapy is used

Surgical resection of cancer remains the frontline therapy for millions of patients annually, but post-operative recurrence is common, with a relapse rate of around 45% for non-small cell lung cancer. The tumour draining lymph nodes (dLN) are resected at the time of surgery for staging purposes, and this cannot be a null event for patient survival and future response to immune checkpoint blockade treatment. This project investigates cancer surgery, lymphadenectomy, onset of metastatic disease, and response to immunotherapy in a novel model that closely reflects the clinical setting. In a murine metastatic lung cancer model, primary subcutaneous tumours were resected with associated dLNs remaining intact, completely resected or partially resected. Median survival after surgery was significantly shorter with complete dLN resection at the time of surgery (49 days (95%CI)) compared to when lymph nodes remained intact (> 88 days; p < 0.05). Survival was partially restored with incomplete lymph node resection and CD8 T cell dependent. Treatment with aCTLA4 whilst effective against the primary tumour was ineffective for metastatic lung disease. Conversely, aPD-1/aCD40 treatment was effective in both the primary and metastatic disease settings and restored the detrimental effects of complete dLN resection on survival. In this pre-clinical lung metastatic disease model that closely reflects the clinical setting, we observe decreased frequency of survival after complete lymphadenectomy, which was ameliorated with partial lymph node removal or with early administration of aPD-1/aCD40 therapy. These findings have direct relevance to surgical lymph node resection and adjuvant immunotherapy in lung cancer, and perhaps other cancer, patients.