General Medical Information

Salivary Glands Cancer

Tumors of the salivary glands comprise those in the major glands (parotid, submandibular, and sublingual) or the minor glands (oral mucosa, palate, uvula, floor of mouth, posterior tongue, retromolar area and peritonsillar area, pharynx, larynx, and paranasal sinuses).[1] The parotid gland is the most common site of major salivary gland tumors, and the palate the most common site of minor salivary gland tumors. Approximately 20% to 25% of parotid tumors, 35% to 40% of submandibular tumors, 50% of palate tumors, and 95% to 100% of sublingual gland tumors are malignant.[2]

Early stage low-grade salivary gland tumors are usually curable by adequate surgical resection alone. The prognosis is more favorable when the tumors are in the major salivary glands, particularly the parotid; less favorable when in the submandibular gland; and least favorable when in the sublingual or a minor salivary gland. Large bulky tumors or high-grade tumors carry a poorer prognosis and may best be treated by surgical resection combined with postoperative irradiation.[3] The prognosis also depends on the gland in which they arise; histology; grade (degree of malignancy); extent of primary tumor (stage); and whether the tumor involves the facial nerve, has fixation to the skin or deep structures, or has spread to lymph nodes or distant sites.[4] Perineural invasion can also occur, particularly in the high-grade adenoid cystic carcinoma, and should be specifically identified and treated.[5] Radiation therapy may provide local control and increased survival benefits when adequate margins cannot be achieved.[6][Level of evidence: 3iiiDi] Unresectable or recurrent tumors may respond to chemotherapy.[7-9] Fast neutron beam radiation therapy or accelerated hyperfractionated photon beam schedules have been shown to be effective in the treatment of inoperable, unresectable, and recurrent tumors.[10-12]

There is a definite association between radiation to the head and neck area and the development of salivary gland tumors. Tobacco use may have a role in causing epidermoid cancer.[13]

References

1. Spiro RH, Thaler HT, Hicks WF, et al.: The importance of clinical staging of minor salivary gland carcinoma. Am J Surg 162 (4): 330-6, 1991.

2. Theriault C, Fitzpatrick PJ: Malignant parotid tumors. Prognostic factors and optimum treatment. Am J Clin Oncol 9 (6): 510-6, 1986.

3. Parsons JT, Mendenhall WM, Stringer SP, et al.: Management of minor salivary gland carcinomas. Int J Radiat Oncol Biol Phys 35 (3): 443-54, 1996.

4. Vander Poorten VL, Balm AJ, Hilgers FJ, et al.: The development of a prognostic score for patients with parotid carcinoma. Cancer 85 (9): 2057-67, 1999.

5. Gormley WB, Sekhar LN, Wright DC, et al.: Management and long-term outcome of adenoid cystic carcinoma with intracranial extension: a neurosurgical perspective. Neurosurgery 38 (6): 1105-12; discussion 1112-3, 1996.
6. Hosokawa Y, Shirato H, Kagei K, et al.: Role of radiotherapy for mucoepidermoid carcinoma of salivary gland. Oral Oncol 35 (1): 105-11, 1999.

7. Borthne A, Kjellevold K, Kaalhus O, et al.: Salivary gland malignant neoplasms: treatment and prognosis. Int J Radiat Oncol Biol Phys 12 (5): 747-54, 1986.

8. Spiro RH: Salivary neoplasms: overview of a 35-year experience with 2,807 patients. Head Neck Surg 8 (3): 177-84, 1986 Jan-Feb.

9. Licitra L, Cavina R, Grandi C, et al.: Cisplatin, doxorubicin and cyclophosphamide in advanced salivary gland carcinoma. A phase II trial of 22 patients. Ann Oncol 7 (6): 640-2, 1996.

10. Wang CC, Goodman M: Photon irradiation of unresectable carcinomas of salivary glands. Int J Radiat Oncol Biol Phys 21 (3): 569-76, 1991.

11. Buchholz TA, Laramore GE, Griffin BR, et al.: The role of fast neutron radiation therapy in the management of advanced salivary gland malignant neoplasms. Cancer 69 (11): 2779-88, 1992.

12. Krüll A, Schwarz R, Engenhart R, et al.: European results in neutron therapy of malignant salivary gland tumors. Bull Cancer Radiother 83 Suppl:125-9s, 1996.

13. Spitz MR, Batsakis JG: Major salivary gland carcinoma. Descriptive epidemiology and survival of 498 patients. Arch Otolaryngol 110 (1): 45-9, 1984.