After diagnosing a patient with cancer of the larynx, a doctor will need to determine what type of cancer it is, the grade of the tumor, and the stage of the cancer. Doctors often establish a preliminary disease stage based on physical exam and findings on imaging that help to identify the extent of disease. In patients who undergo surgery, a more well-defined disease stage is determined based on pathology after surgery.
Type
The most common type of subglottic cancer is squamous cell carcinoma, making up 95% of all laryngeal cancers. Squamous cell carcinoma is a cancer that starts from abnormal cells that line the larynx. In more rare cases, other types of possible diagnoses are:
- Salivary gland cancers: There are minor salivary glands located under the lining of the throat. This is why cancers that we typically see in salivary glands can arise in this region and they include diagnoses such as mucoepidermoid carcinomas, adenocarcinomas and adenoid cystic carcinomas, to name a few. See Salivary Gland Cancer for more information.
- Lymphoma: The throat is lined with lymphoid cells. Some major sites of lymphoid tissue include the adenoids in the nasopharynx (part of the throat behind the nose) and tonsils in the oropharynx. However, small amounts of lymphoid tissue lines the larynx as well, and rarely a lymphoma can arise from the subglottis.
- Mucosal melanoma: These cancers come from skin cells that give skin its color. The cells are also present in the lining (mucosa) of the aerodigestive tract. Overall, mucosal melanoma of the larynx is rare, and it occurs in the supraglottis more commonly than in the glottis or subglottis.
Less common types of benign and malignant subglottic tumors
- Sarcomas such as chondrosarcoma, liposarcoma, synovial sarcoma, and malignant fibrous histiocytoma. Low grade chondrosarcomas are quite commonly seen arising from the cricoid cartilage and can grow slowly in this location leading to changes in breathing and voice.
- Neuroendocrine tumors such as neuroendocrine carcinoma, paraganglioma, carcinoma tumors, and small cell carcinoma.
- Cancer spread (metastasis) from another site. One of the more common tumors to spread to the subglottis and trachea is thyroid cancer, which can extend to this region by invasion of the cartilage. These types of cancer are often associated with vocal cord paralysis as well.
- Benign tumors such as lipoma, neurofibroma, adenoma, chondroma, and granular cell tumors.
