Lung cancer metastasis-induced distal esophageal segmental spasm confirmed by individualized peroral endoscopic myotomy: A case report.

Background: Peroral endoscopic myotomy (POEM) has been widely performed as a standard treatment for achalasia; however, its efficacy and safety for treating distal esophageal segmental spasms induced by cancer metastasis remain unknown.

Case summary: A 72-year-old male was referred to our hospital and complained of progressive dysphagia for two years. Endoscopy revealed a 2 cm long segment esophageal stenosis with intact mucosa and normal cardia. Computed tomography showed a right upper lung mass, and pathology of the right pleural effusion confirmed the diagnosis of right upper lung adenocarcinoma with multiple rib and mediastinal lymph node metastases and right malignant pleural effusion. Individualized POEM was performed first to alleviate dysphagia, and the final diagnosis was changed to esophageal muscle metastasis arising from lung adenocarcinoma. After treatment, the patient could eat soft solid food and received multiple rounds of pembrolizumab-combination chemotherapy. The patient's progression-free survival was approximately 16 months. Long stable disease was obtained during the 24-month follow-up.

Conclusion: The incidence of distal esophageal segmental spasms induced by muscular metastasis arising from lung adenocarcinoma is extremely low. Individualized POEM can effectively improve a patient's nutritional status before subsequent chemotherapy can be combined with immune checkpoint inhibitors.