A 58-year-old male smoker presents with a 3-month history of progressive hoarseness and throat pain. He denies dysphagia or dyspnea. On laryngoscopy, a unilateral, irregular, ulcerated lesion is seen on the left vocal cord with extension to the anterior commissure. Biopsy confirms squamous cell carcinoma. CT neck shows a 2 cm lesion confined to the larynx with no cervical lymph node involvement. What is the TNM stage of this tumor?

Explanation

## TNM Staging of Laryngeal Carcinoma (AJCC 8th Edition) ### Tumor (T) Classification for Glottic Larynx **Key Point:** TNM staging of glottic laryngeal cancer depends critically on the extent of vocal cord involvement and mobility status. | T Stage | Criteria | | --- | --- | | T1a | Tumor confined to one vocal cord with normal mobility | | T1b | Tumor involves both vocal cords with normal mobility | | T2 | Tumor extends to supraglottis and/or subglottis, and/or with impaired vocal cord mobility; OR extends to anterior commissure with normal or impaired mobility | | T3 | Tumor confined to larynx with **vocal cord fixation** OR involves postcricoid area, pre-epiglottic space, paraglottic space, or inner cortex of thyroid cartilage | | T4a | Tumor invades through thyroid cartilage and/or extends beyond larynx | | T4b | Tumor invades prevertebral space, mediastinum, or encases carotid artery | ### Analysis of This Case **High-Yield:** The critical discriminator between T2 and T3 in glottic carcinoma is **vocal cord fixation**. Without fixation, anterior commissure involvement places the tumor at T2. 1. **Lesion location**: Left vocal cord with extension to the anterior commissure 2. **Anterior commissure involvement**: Represents extension beyond a single vocal cord subsite → upgrades from T1 to T2 3. **Vocal cord mobility**: The stem does **not** describe vocal cord fixation or impaired mobility; no fixation = no T3 4. **Cartilage/extralaryngeal invasion**: Absent → rules out T4a 5. **Conclusion**: A 2 cm glottic lesion extending to the anterior commissure **without vocal cord fixation** = **T2** **Clinical Pearl:** Per AJCC 8th Edition (and as referenced in Cummings Otolaryngology), anterior commissure involvement alone does NOT mandate T3 staging. T3 requires documented vocal cord fixation. In the absence of fixation, this lesion is correctly staged as T2 N0 M0. ### Node (N) and Metastasis (M) Status - **N0**: No cervical lymph node involvement (explicitly stated on CT neck) - **M0**: No distant metastasis (no systemic disease mentioned) **Correct Stage: T2 N0 M0** *Reference: AJCC Cancer Staging Manual, 8th Edition; Cummings Otolaryngology – Head and Neck Surgery, 7th Edition, Chapter on Laryngeal Carcinoma.*