Staging of Supraglottic, Glottic & Subglottic Tumour

Staging of Supraglottic Tumours

• T1: Tumour limited to one subsite of supraglottis with normal vocal cord mobility.
• T2: Tumour invades the mucosa of more than one adjacent subsite of the supraglottis, glottis, or region outside the supraglottis.
• T3: Tumor limited to larynx with vocal-cord fixation or invades post-cricoid area, pre-epiglottis tissues, paraglottic space, thyroid cartilage erosion.
• T4a: Tumour spreads through thyroid cartilage, trachea, soft tissues of the neck, deep/extrinsic muscle of the tongue, strap muscles, and thyroid oesophagus.
• T4b: Tumor spreads prevertebral space, mediastinal structures, carotid artery.

T → 1 subsite of larynx/V.C. mobile 1

T2 → > 1 subsite of larynx

T3

• V.C fixed
• Involvement of larynx
• Involvement of inner Perichondrium of cartilage

T4a → Local spread

T4b → Distant spread

Also read: Acute Infections of the Larynx

Staging of Glottic Tumour

T1: Tumour limited to vocal cord(s) with normal mobility.

T1a: Tumour limited to one vocal cord.

T1b: Tumour involves both vocal cords.

T2: Tumour extends to supraglottis and/or subglottis and/or with impaired vocal cord mobility.

T3: Tumour limited to larynx with vocal-cord fixation, paraglottis space, thyroid cartilage erosion.

T4a: Tumour invades through thyroid cartilage, trachea, soft tissues of neck, deep/extrinsic muscle of tongue, strap muscles, thyroid, and oesophagus.

T4b: Prevertebral space, mediastinal structures, carotid artery

Staging of Subglottic Tumour

T1: Tumour limited to subglottis

T2: Tumour extends to vocal cord(s) with normal or impaired mobility.

T3: Tumour limited to the larynx with vocal-cord fixation.

T4a: Tumour invades through thyroid cartilage, trachea, soft tissues of neck, deep/extrinsic muscle of tongue, strap muscles, thyroid, oesophagus

T4b: Prevertebral space, mediastinal structures, carotid artery

Also read: Benign Lesions of the Larynx

Staging of Regional Lymph Nodes

• Nx: regional lymph nodes cannot be assessed.
• N0: No regional lymph node metastasis
• N1: Metastasis in a single ipsilateral lymph node 3 cm or less in greatest dimension.
• N2: metastasis in a single ipsilateral lymph node, more than 3-6 cm but not more than 6 cm in the greatest dimension, or in multiple ipsilateral lymph nodes, none more than 6 cm in
• greatest dimension, or in bilateral or contralateral lymph nodes, none more than 6 cm in greatest dimension.
• N2a: Metastasis in a single ipsilateral lymph node, more than 3 cm but not more than 6 cm in greatest dimension.
• N2b: Metastasis in multiple ipsilateral lymph nodes, none more than 6 cm in greatest dimension.
• N2c: metastasis in bilateral or contralateral lymph nodes, none more than 6 cm in greatest dimension.
• N3: metastasis in a lymph node, more than 6 cm in greatest dimension.
• N3a: no extra nodal involvement.
• N3b: extra nodal involvement.

Distant Metastasis

• Mx: Distant metastasis cannot be assessed.
• M0: No distant metastasis
• M1: Distant metastasis

Also read: Upper Airway Obstruction: Causes, Management

Laryngeal Premalignancy/Dysplasia

It is of clinical significance because it can undergo malignant transformation (11-25%). It is also known as laryngeal intraepithelial neoplasia. It can be high grade or low grade.

Excision Techniques

Cold steel or laser resection is recommended over monopolar cautery. A carbon dioxide laser is recommended owing to minimal penetration, which reduces collateral damage. Laser ablation is discouraged as no specimen will be available for diagnosis and there is a higher risk of damage to the voice. Vocal cord stripping is not recommended due to the high risk of damage to the vocal cord. Radiotherapy: Only in cases with very high risk or suspicion of conversion to malignancy and surgical resection is not possible owing to patient or tumour factors.

Management of Persistent or Recurrent Lesions

Localized mild or moderate local dysplasia should be offered re-excision. Widespread mild or moderate widespread dysplasia may be observed or excised. Recurrent focal severe dysplasia should be managed as a T1 laryngeal carcinoma with surgical resection where possible.

Radiotherapy may be considered. For persistent or recurrent widespread severe dysplasia, radiotherapy should be considered as an option.

Also read: Upper Airway Obstruction: Causes, Management

Management of Early Stage Laryngeal Cancer

• In early cancer I or II—surgery or radiotherapy—a single modality is used.
• It has an 85-95% cure rate.  Surgery is a single-step procedure.
• For the mid-cord lesions, transoral laser microsurgery (TLM) is used. Larger lesions are treated by radiotherapy for 6-7 weeks. The choice of treatment is based on patient choices and the likelihood of advantageous voice outcomes following the treatment.

Management of T3 Glottic Cancers

Primary non-surgical treatment with concurrent CRT remains the preferred treatment option in patients with: good performance status, minimal or no comorbidity. Disease is limited to the confines of the larynx with no cartilage invasion. Functioning larynx with no airway compromise

Standard concurrent CRT regimes include cisplatin 100 mg/m2 on days 1, 22, and 43 of RT and carboplatin/5FU on weeks 1 and 5 during radiotherapy. In patients where chemotherapy is contraindicated, cetuximab and monoclonal antibodies could be considered as an alternative.

Induction chemotherapy regimens that include a combination of cisplatin and 5FU given every 3 weeks to a total of 2-3 cycles may improve survival and reduce distant metastases in selected patients.

Also read: Larynx Inflammatory Lesions

Management of T4 Glottic Cancers 

Laryngeal cancer that extends outside the framework of the larynx should be treated by primary surgery. Usually total laryngectomy is performed, but for smaller selected tumors, open partial laryngectomy may be an option. All patients will need the neck addressed based on the extent of neck disease. N0 necks will need bilateral level II-IV neck dissection. Postoperative radiotherapy +/- concurrent chemotherapy improves locoregional control and survival.

Points to remember

Side effects of radiation therapy

• Inappropriate swallowing
• Xerostomia
• Necrosis of cartilage

Also read: Understanding Objective Voice Evaluation and Acoustic Analysis

Hope you found this blog helpful for your ENT residency Larynx preparation. For more informative and interesting posts like these, keep reading PrepLadder’s blogs.