Complete remission of combined pulmonary large cell neuroendocrine carcinoma: a case report.

Pulmonary large cell neuroendocrine carcinoma (LCNEC), which accounts for approximately 1% of all lung cancers, is a rare and highly aggressive malignancy with a poor prognosis. Therefore, it is important to devise an effective treatment strategy. In the treatment of locally advanced complex LCNEC, it is unique to first administer radiotherapy combined with albumin-bound paclitaxel plus carboplatin, followed by durvalumab for immune maintenance treatment after concurrent radiotherapy and chemotherapy to achieve complete remission. We report a 54-year-old man who smoked and who felt chest tightness for 2 weeks and was diagnosed as having combined pulmonary LCNEC. For patients with locally advanced pulmonary LCNEC, chemoradiotherapy increases overall survival. After surgical resection and chemoradiotherapy, our patient achieved complete remission. Durvalumab was then started to consolidate the treatment. After six courses of immune maintenance therapy, the patient developed grade 2 immune-related pneumonitis and took prednisone orally until the symptoms resolved, and then reached complete remission again. The patient achieved complete remission, which was a challenge with this rare carcinoma, through albumin-bound paclitaxel plus platinum-based chemotherapy combined with radiotherapy and durvalumab for immune maintenance therapy. This approach may provide a treatment option for locally advanced combined pulmonary LCNEC.