A Multimodal Biomarker Predicts Dissemination of Bronchial Carcinoid

Area of Science:

• Pulmonology
• Oncology
• Pathology

Background:

• Bronchial carcinoid tumors have low metastatic potential after curative treatment.
• Current typical (TC) and atypical carcinoid (AC) grading has limited prognostic value.
• Yearly follow-up is standard for all patients due to grading limitations.

Purpose of the Study:

• To evaluate the prognostic value of novel immunohistochemical (IHC) markers.
• To enhance the current gradation of bronchial carcinoids for better risk stratification.
• To identify independent predictors of distant metastasis in bronchial carcinoids.

Main Methods:

• Retrospective study of 171 bronchial carcinoid patients with curative treatment.
• Evaluation of histopathological characteristics: Ki-67, p16, Rb, OTP, CD44, tumor diameter.
• Multivariate regression and Kaplan-Meier analysis to assess metastasis risk.

Main Results:

• Mitotic count, Ki-67, and OTP were identified as independent risk factors for distant metastases.
• A combination of risk predictors (AC, Ki-67 ≥ 5%, loss of OTP or CD44) significantly associated with metastasis risk (p < 0.0001).
• 86% of patients with all three risk factors developed distant metastasis.

Conclusions:

• Mitotic count, proliferation index (Ki-67), and OTP IHC are independent predictors of bronchial carcinoid dissemination.
• Comprehensive histopathological analysis (Ki-67, OTP, CD44) can improve distant metastasis risk determination.
• These markers can aid in refining follow-up strategies beyond current carcinoid classification.