High-Grade Neuroendocrine Carcinoma Within a Tracheal Polyp: A Case Report

Area of Science:

• Oncology
• Genomics
• Virology

Background:

• Primary tracheal carcinomas are exceptionally rare, affecting approximately one in a million individuals annually.
• This report describes a novel case of a polypoid, high-grade neuroendocrine carcinoma of the trachea.

Observation:

• The resected tumor showed superficial mucosal invasion without metastasis.
• Histological examination revealed high-grade features, necrosis, and a high mitotic index.
• Immunohistochemistry was positive for neuroendocrine markers, p16, and showed an elevated Ki-67 index.

Findings:

• Whole-genome sequencing identified a distinct mutational signature unrelated to other neuroendocrine carcinomas.
• No known driver or targetable mutations were detected.
• Analysis suggests human papillomavirus-18 integration plays a role in the tumor's pathogenesis.
• The patient experienced distal recurrence and widespread pulmonary dissemination, likely via aerogenous spread.

Implications:

• This is the first comprehensive characterization of this rare tracheal tumor, encompassing its genomic profile, pathogenesis, and clinical course.
• The findings highlight a potential link between human papillomavirus-18 and tracheal neuroendocrine carcinoma development.
• Understanding the unique mutational landscape and pathogenesis is crucial for future diagnostic and therapeutic strategies.