A 58-year-old Indian male with a 35 pack-year smoking history presents with progressive dysphagia, odynophagia, and stridor for 2 weeks. He has lost 4 kg in the past month. Flexible laryngoscopy shows a large, infiltrative supraglottic mass involving the aryepiglottic fold and extending into the false vocal cords. The mass is mobile and there is no vocal cord fixation. CT neck with contrast reveals the tumor is confined within the laryngeal framework with no cartilage invasion, but there is a 2 cm ipsilateral level III lymph node. Biopsy confirms squamous cell carcinoma. What is the overall TNM stage of this tumor?

Explanation

## TNM Staging and Overall Stage Determination in Laryngeal Carcinoma ### Step 1: Determine T Stage (Supraglottic Tumor) **Key Point:** Supraglottic tumors are staged differently from glottic tumors. Supraglottic involvement is inherently considered more advanced. | T Stage | Supraglottic Definition | |---------|------------------------| | T1 | Tumor limited to one subsite of supraglottis with normal vocal cord mobility | | T2 | Tumor invades mucosa of more than one adjacent subsite of supraglottis or glottis, or tumor with impaired vocal cord mobility | | T3 | Tumor limited to larynx with vocal cord fixation and/or invasion of postcricoid area, medial wall of piriform sinus, or anterior commissure | | T4a | Tumor invades through thyroid cartilage and/or extends to soft tissues outside larynx | **Clinical Analysis:** - Tumor involves **aryepiglottic fold AND false vocal cords** = multiple subsites - **No vocal cord fixation** (mobility preserved) - **No cartilage invasion** - **Confined within laryngeal framework** → **T Stage = T2** (involves more than one adjacent subsite) ### Step 2: Determine N Stage (Lymph Node Involvement) **High-Yield:** Lymph node staging is based on size, number, and laterality, NOT location. | N Stage | Definition | |---------|------------| | N0 | No regional lymph node metastasis | | N1 | Metastasis in a single ipsilateral lymph node, ≤3 cm | | N2a | Metastasis in a single ipsilateral lymph node, 3–6 cm | | N2b | Metastasis in multiple ipsilateral lymph nodes, none >6 cm | | N2c | Metastasis in bilateral or contralateral lymph nodes, none >6 cm | | N3 | Metastasis in a lymph node >6 cm | **Clinical Analysis:** - Single ipsilateral level III lymph node - Size: 2 cm (≤3 cm) → **N Stage = N1** ### Step 3: Overall Stage Grouping **Mnemonic:** AJCC Stage Grouping for Laryngeal Cancer — **Remember: T + N + M → Overall Stage** | Overall Stage | T | N | M | |---------------|---|---|---| | Stage I | T1 | N0 | M0 | | Stage II | T2 | N0 | M0 | | Stage III | T1–T3 | N1 | M0 | | Stage III | T3 | N0 | M0 | | Stage IV A | T4a | Any N | M0 | | Stage IV B | T4b | Any N | M0 | | Stage IV C | Any T | Any N | M1 | **This Patient:** - T2 N1 M0 → **Stage III** **Clinical Pearl:** The presence of any N1 disease (single ipsilateral node ≤3 cm) automatically elevates a T1–T3 tumor to Stage III, regardless of T stage. This reflects the prognostic impact of nodal involvement on survival. **Warning:** Do not confuse level III lymph nodes (anatomical location: middle jugular chain) with N3 stage (size-based: >6 cm). The anatomical location does not determine N stage — only size, number, and laterality do.