Perioperative outcomes and lymph node assessment after induction therapy in patients with clinical N1 or N2 non-small cell lung cancer.

BACKGROUND

Induction therapy has been shown to benefit patients with resectable stage-2 or stage-3 non-small cell lung cancer (NSCLC). We aimed to determine if induction chemotherapy (CTx) with or without radiation therapy (± RT) for NSCLC with clinical lymph node (LN) involvement (cN1 or cN2) affects LN dissection or perioperative outcomes during robotic-assisted video thoracoscopic (RAVTS) lobectomy.

METHODS

We retrospectively analyzed patients who underwent RAVTS lobectomy for NSCLC over 45 months. We assessed clinical LN status by CT scan, PET scan, endobronchial ultrasound, and/or mediastinoscopy. We grouped patients with cN1 or cN2 as: "no induction therapy", "induction CTx alone" (ICTx), or "induction CTx + RT" (ICTx + RT). Intraoperative estimated blood loss (EBL), operative times, tumor size, LN status, and restaging were noted.

RESULTS

Of 256 NSCLC patients who had lobectomy, there were 52 cN1 or cN2 patients, of whom 39 patients had "no induction", 7 had ICTx, and 6 had ICTx + RT. Higher rates of recurrent laryngeal nerve (RLN) injury, tracheal/bronchial injury, and pulmonary embolism were observed with ICTx ± RT (P=0.02, 0.04, and 0.02, respectively). Total number of complications was not significantly different, nor were perioperative outcomes, such as EBL, operative time, and in-hospital mortality. Fewer N2 LN stations were assessed after ICTx ± RT (3.7±0.2 vs. 4.2±0.2 stations; P=0.04), but total number of LNs reported were not significantly different (13.0±2.3 vs. 16.2±1.0 LNs, P=0.22). Of "no induction" patients, 15.4% were upstaged pathologically; no patients were upstaged after induction therapy. While 30.8% of ICTx ± RT patients were downstaged, 38.5% of "no induction" patients were also downstaged on final pathology.

CONCLUSIONS

Induction CTx ± RT for cN1 or cN2 NSCLC patients did not affect EBL, operative times, or in-house mortality after RAVTS lobectomy. Patients undergoing RAVTS lobectomy after ICTx+ RT may be at greater risk for RLN injury, tracheal/bronchial injury, and pulmonary embolism. Fewer N2 LN stations, but not numbers of LNs, are assessed after ICTx ± RT. Induction therapy does not lead to increased downstaging.