Tracheobronchial chondritis as an immune-related adverse event occurring during the administration of nivolumab for recurrent hypopharyngeal squamous cell carcinoma.

Tracheobronchial chondritis is a rare immune-related adverse event (irAE) associated with immune checkpoint inhibitors. We report a case wherein tracheobronchial chondritis occurred while administering nivolumab for recurrent hypopharyngeal squamous cell carcinoma (SCC) in a man diagnosed with T2N3bM0 stage IVB hypopharyngeal SCC. After treatment with cisplatin and radiotherapy followed by left and right neck dissection, local recurrence was observed in the hypopharynx. Because of the difficulty of salvage surgery, we administered 240 mg/body of nivolumab. After 9 cycles of nivolumab, the patient was judged to have complete response. After 10 cycles, he had cough and sputum, for which prompting us to perform imaging tests. Computed tomography (CT) showed edematous thickening around the trachea and bilateral bronchi and elevated amounts of adjacent subcutaneous fat tissue. Positron emission tomography-CT showed diffuse fluorodeoxyglucose uptake in the trachea and bilateral bronchi, bronchial endoscopy showed redness and swelling throughout the bronchi, and biopsy showed partial mucosal erosion, inflammatory cell (lymphocyte) infiltration, interstitial edema, and desmoplasia. The patient was diagnosed with tracheobronchial chondritis as an irAE resulting from administering anti-programmed death-1 monoclonal antibody. After four-day prednisolone treatment, his cough and sputum disappeared; after two weeks, tracheobronchial chondritis no longer appeared on CT.

Laryngeal Cancer With Lung Metastases Showing Long-Term Complete Response and Delayed Immune-Related Adverse Event After Nivolumab Discontinuation.

We report a case of laryngeal cancer with multiple lung metastases that maintained a complete response (CR) for 18 months after discontinuing nivolumab treatment, with colitis developing 5 months after drug discontinuation. A 65-year-old man was diagnosed with T3N2cM0 stage IVA right supraglottic squamous cell carcinoma that progressed after 1 course of TPF (cisplatin, docetaxel, and 5-fluorouracil) as induction chemotherapy. He underwent total laryngectomy, bilateral neck dissection, pharyngeal reconstruction with anterolateral thigh flap, and creation of a permanent tracheostoma; extranodal extension was detected in the right cervical lymph node metastasis, and the patient underwent adjuvant radiotherapy. Multiple lung metastases occurred during radiotherapy, and the patient was deemed platinum refractory; nivolumab treatment was thus initiated. The tumor proportion score for programmed death-ligand 1-evaluated via antibody testing of the laryngeal tumor-was <1. The patient received 240 mg/body nivolumab every 2 weeks; a computed tomography performed after course 16 of nivolumab treatment confirmed a CR. He exhibited grade 2 thyroid dysfunction, grade 1 interstitial pneumonia, and grade 2 colitis after 6, 7, and 14 months of receiving nivolumab, respectively; treatment was discontinued as despite maintaining a CR, interstitial pneumonia occurred twice. Colitis appeared 5 months after nivolumab discontinuation; nevertheless, a CR was maintained after 18 months.