Brief Summary: Phase II, single-arm, open-label single center study that assess clinical feasibility and safety of 3 cycles neoadjuvant Toripalimab plus chemotherapy in rare mutations stage IIB-IIIB NSCLC followed by optional adjuvant treatment upon investigators' decisions.

Detailed Description: 30 eligible patients will be enrolled and 3 cycles of Toripalimab 240mg + chemotherapy (Nab-paclitaxel + carboplatin, or pemetrexed + carboplatin) will be administered. Rare mutations include RET fusions, BRAF (V600E or non-V600E but confirmed driver mutations), ERBB2 exon20 insertion, MET amplification (FISH confirmed) or exon 14 skipping. Dynamic blood samples before, during or after neoadjuvant treatment will be obtained for exploratory analysis. Patients who showed inferior response to neoadjuvant treatment leading to unresectable disease will be scheduled for local radiation or other potential subsequent treatment regarding multidisciplinary discussion. After completion of local treatment (surgery or radiation), patients will be provided with optional adjuvant treatment including chemotherapy or/and rare mutations TKI upon investigators' consideration. The primary objective of the study is pathological complete response (pCR) defined as no residue tumor found in both primary lung cancer and metastatic lymph nodes.