## Distinguishing Supraglottic from Transglottic Carcinoma **Key Point:** Transglottic carcinoma crosses the laryngeal ventricle to involve both supraglottic and glottic structures, fundamentally changing the tumor biology and prognosis compared to pure supraglottic disease. ### Supraglottic Carcinoma (False Vocal Cord Origin) - **Confined above the laryngeal ventricle** (epiglottis, aryepiglottic folds, false vocal cords) - **True vocal cords remain uninvolved** initially → vocal cord mobility preserved - No subglottic extension - Presents with dysphagia, throat pain, or neck mass (not hoarseness) - Rich lymphatic drainage → high rate of cervical metastasis (40–50%) - Laryngeal framework integrity maintained in early disease ### Transglottic Carcinoma (Crosses Laryngeal Ventricle) **High-Yield:** Transglottic tumors are defined by **crossing the laryngeal ventricle to involve BOTH supraglottic and glottic structures**, including the true vocal cords and often extending to the subglottis. - **True vocal cord involvement** with fixation or impaired mobility - **Subglottic extension** (by definition, crosses ventricle) - Hoarseness + dysphagia (combined glottic + supraglottic symptoms) - More aggressive behavior than pure supraglottic disease - Often T3–T4 at diagnosis - Worse prognosis than supraglottic alone - Requires more extensive surgery (total laryngectomy often needed) ### Comparison Table | Feature | Supraglottic | Transglottic | |---------|--------------|---------------| | **Anatomic extent** | Above ventricle only | Crosses ventricle | | **True vocal cord involvement** | No (early disease) | Yes | | **Subglottic extension** | Absent | Present | | **Vocal cord mobility** | Preserved | Fixed/impaired | | **Hoarseness** | Absent early | Present | | **Dysphagia** | Present | Present | | **Stage at Dx** | T1–T3 | T3–T4 | | **Laryngeal framework** | Intact | Often breached | **Clinical Pearl:** The patient in the stem has a false vocal cord tumor (supraglottic origin), but the question asks what **distinguishes** it from transglottic disease. The presence of true vocal cord involvement and subglottic extension would indicate transglottic disease, making option 0 the best discriminator. **Mnemonic:** **"TransGlottic = Glottic + Supraglottic"** — it crosses the ventricle, so it has features of both regions, including true cord involvement and subglottic spread. **Tip:** On imaging or laryngoscopy, if you see a supraglottic tumor that also involves the true vocal cords or extends below the ventricle, reclassify it as transglottic and expect worse prognosis and need for total laryngectomy. [cite:Harrison 21e Ch 183] 
Sign up free to access AI-powered MCQ practice with detailed explanations and adaptive learning.