Bronchopulmonary carcinoid tumor presenting with polymyositis

Area of Science:

• Neurology
• Oncology
• Pathology

Background:

• Bronchopulmonary carcinoid tumors are neuroendocrine neoplasms with variable clinical presentations.
• Paraneoplastic syndromes can manifest as the initial or sole sign of an underlying malignancy.
• Polymyositis is an idiopathic inflammatory myopathy characterized by proximal muscle weakness.

Observation:

• A patient presented with proximal muscle weakness, initially diagnosed as polymyositis via laboratory analysis and muscle biopsy.
• Chest imaging subsequently identified a typical bronchopulmonary carcinoid tumor.
• The patient's symptoms and laboratory abnormalities resolved completely following surgical resection of the tumor.

Findings:

• This case demonstrates a rare association between a typical carcinoid tumor and the paraneoplastic syndrome of polymyositis.
• The findings suggest that carcinoid tumors can induce autoimmune responses leading to inflammatory myopathy.
• Resolution of polymyositis after tumor removal strongly supports a paraneoplastic etiology.

Implications:

• This report expands the spectrum of paraneoplastic syndromes associated with bronchopulmonary carcinoid tumors.
• Early recognition of polymyositis in the context of unexplained muscle weakness may warrant investigation for underlying carcinoid tumors.
• Understanding this rare paraneoplastic link can improve diagnostic and therapeutic strategies for affected patients.