Salivary gland tumor natural history, complications and prognosis
|
Salivary gland tumor Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Salivary gland tumor natural history, complications and prognosis On the Web |
|
American Roentgen Ray Society Images of Salivary gland tumor natural history, complications and prognosis |
|
FDA on Salivary gland tumor natural history, complications and prognosis |
|
CDC on Salivary gland tumor natural history, complications and prognosis |
|
Salivary gland tumor natural history, complications and prognosis in the news |
|
Blogs on Salivary gland tumor natural history, complications and prognosis |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]Associate Editor(s)-in-Chief: Simrat Sarai, M.D. [2]
Overview
If left untreated, patients with salivary gland tumors may progress to develop metastasis. Common complications of salivary gland tumors include metastasis, injury to the facial nerve, and Frey's syndrome. Prognosis is generally good, and the 5 year mortality rate of patients with salivary gland cancer that has not spread at the time of diagnosis is 91%.[1][2]
Natural history
The clinical presentation of a salivary gland neoplasm depends upon its specific site of origin and the extent of involvement of adjacent organs. The most common symptom of major salivary gland cancer is a painless lump in the affected gland, sometimes accompanied by paralysis of the facial nerve. Symptoms due to more advanced minor salivary gland tumors are a function of the location of the tumor and can include nasal obstruction, congestion, vision changes, or trismus when present in the nasal cavity or maxillary sinus. Minor salivary gland tumors involving the nasopharynx usually present at an advanced stage; invasion of the skull base, intracranial extension, or involvement of cranial nerves is common.[2] If left untreated, patients with salivary gland cancer may progress to develop metastasis. Distant metastases frequently localizes to the lung, followed by liver, and bone.The majority of salivary gland tumors are noncancerous and slow growing.[1]
Complications
Complications of salivary gland tumors include the following:[2]
- Metastasis
- Rarely, surgery to remove the tumor can injure the nerve that controls movement of the face.
- Frey's syndrome
Prognosis
Early-stage low-grade malignant salivary gland tumors are usually curable by adequate surgical resection alone. The prognosis is more favorable when the tumor is in a major salivary gland; the parotid gland is most favorable, then the submandibular gland; the least favorable primary sites are the sublingual and minor salivary glands. Large bulky tumors or high-grade tumors carry a poorer prognosis. The prognosis also depends on the following:[2]
- Gland in which they arise
- The prognosis is more favourable when the tumor is in a major salivary gland. Parotid gland cancers have the most favorable prognosis, than the submandibular gland and the least favourable primary sites are the sublingual and minor salivary glands. Minor salivary gland tumors tend to be more aggressive in nature than major salivary gland tumors.
- Grade of the tumor
- Both grade and tumor type are important prognostic factors. Low-grade tumors have a better prognosis than high-grade tumors. Some types of salivary gland cancers have a better prognosis than others.
- Stage of the salivary gland tumor
- Tumor stage is one of the most important prognostic factors. The survival rate decreases as the stage of the cancer increases.
- Whether the tumor involves the facial nerve, has fixation to the skin or deep structures, or has spread to lymph nodes or distant sites.
- A salivary gland cancer that causes a loss of facial muscle movement (facial nerve paralysis) is often associated with cancer that has spread to the lymph nodes and distant sites. It usually indicates a poor prognosis.
- Undifferentiated carcinoma, adenocarcinoma, adenoid cystic carcinoma and squamous cell carcinoma are the types of salivary gland cancers that most often affect the facial nerves. Patients with salivary gland cancer that has spread to the cervical lymph nodes have a poorer prognosis than those who have no metastasis. Some tumors are more likely to spread to the lymph nodes in the neck, while other tumors do not spread as often. Cancers that spread to distant sites within the body generally have a poor prognosis. The chances of having distant metastasis is greater with increased tumor size (T) and lymph node (N) involvement (T and N classifications).
- Salivary gland tumors with a high malignant potential are more likely to spread to regional lymph nodes and may result in a palpable mass. According to location of the salivary gland the lymphatic drainage varies: the first site of lymphatic spread is the intraparotid lymph nodes, for parotid malignancies followed by level I and level II cervical nodes. Submandibular gland tumors spread to perivascular nodes and then to the cervical region.
- The sublingual gland drains to the submandibular and submental nodes, and the minor salivary glands within the oropharynx drain to the retropharyngeal nodes. Adenoid cystic carcinoma is associated with a high risk of distant metastases that can occur as late as 10 to 20 years after diagnosis and treatment. Usually, removing the tumor with surgery cures the condition. In rare cases, the tumor is cancerous and further treatment is required.
- Gender
- Men seem to have poorer outcomes than women. The reasons for this are unknown at this time.
- Histology
- The prognosis of salivary gland tumors depends on the histological subtype. Histological subtypes of salivary gland tumors can be found here.
The five-year survival rate for people with salivary gland cancer that has not spread at the time of diagnosis is 91%. The five-year survival rate for people with salivary gland cancer that has spread to the surrounding lymph nodes and the five-year survival rate for people with salivary gland cancer that has spread to parts of the body far away from the salivary gland, is 75% and 39% respectively.
Survival rates for salivary gland cancer by stage
| Stage | 5-year Relative survival rate |
|---|---|
|
91% |
|
75% |
|
65% |
|
39% |
References
- ↑ 1.0 1.1 Licitra, L (2003). "Major and minor salivary glands tumours". Critical Reviews in Oncology/Hematology. 45 (2): 215–225. doi:10.1016/S1040-8428(02)00005-7. ISSN 1040-8428.
- ↑ 2.0 2.1 2.2 2.3 Salivary gland cancer. National cancer institute(2015) http://www.cancer.gov/types/head-and-neck/hp/salivary-gland-treatment-pdq#link/_413_toc Accessed on November 11, 2015