A 58-year-old male smoker presents with progressive hoarseness for 3 months and persistent throat pain. He denies dysphagia or dyspnea. On laryngoscopy, a white, irregular lesion is seen on the left vocal cord. Biopsy confirms squamous cell carcinoma. CT chest shows no distant metastases. Laryngeal mobility is intact bilaterally. Which TNM stage best describes this tumor?

Explanation

## TNM Staging of Laryngeal Carcinoma **Key Point:** TNM staging in laryngeal cancer is based on tumor size, vocal cord involvement, and fixation status. ### T-Stage Classification for Glottic Laryngeal Cancer | T-Stage | Definition | |---------|------------| | T1 | Tumor limited to one vocal cord; normal mobility | | T2 | Tumor involves both vocal cords OR extends to supraglottis/subglottis; impaired mobility | | T3 | Tumor limited to larynx with vocal cord fixation | | T4a | Tumor invades thyroid cartilage and/or soft tissues outside larynx | | T4b | Tumor invades prevertebral space, mediastinum, or encases carotid artery | ### Clinical Analysis of This Case 1. **Lesion location:** Left vocal cord only (unilateral) 2. **Laryngeal mobility:** Intact bilaterally (no fixation) 3. **Extent:** No mention of supraglottic/subglottic extension 4. **Cartilage invasion:** No evidence on imaging **High-Yield:** A lesion confined to one vocal cord with preserved mobility = **T1 disease**, regardless of size. This is the earliest stage of glottic carcinoma. ### Prognostic Implications **Clinical Pearl:** T1 N0 M0 glottic carcinoma has excellent prognosis (>90% 5-year survival) with either radiation therapy or transoral laser microsurgery (TLM). Voice preservation is achievable with both modalities. ### Key Discriminators - **T1 vs T2:** T2 requires either bilateral cord involvement OR extension beyond the vocal cord (supraglottis/subglottis) - **T2 vs T3:** T3 specifically denotes vocal cord **fixation** (immobility), indicating cricoarytenoid joint involvement - **T3 vs T4a:** T4a crosses the laryngeal framework (thyroid cartilage breach)