You are in: eMedicine Specialties > Otolaryngology and Facial Plastic Surgery > HEAD AND NECK ONCOLOGY Malignant Tumors of the TonsilArticle Last Updated: Feb 14, 2007AUTHOR AND EDITOR INFORMATIONSection 1 of 9
  Author: Gerard Domanowski, MD †, Former Associate Chair, Former Associate Professor in Pathology, Former Associate Professor of Otolaryngology and Oral Surgery, Department of Pathology, McGill University Health Center Editors: Terance (Terry) Ted Tsue, MD, Vice-Chairman for Administrative Affairs, Professor, Residency Program Director, Department of Otolaryngology-Head and Neck Surgery, University of Kansas School of Medicine; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Karen Hall Calhoun, MD, Chair, Professor, Department of Otolaryngology-Head and Neck Surgery, University of Missouri; Christopher L Slack, MD, Otolaryngology-Facial Plastic Surgery, Private Practice, Associated Coastal ENT; Medical Director, Treasure Coast Sleep Disorders; Arlen D Meyers, MD, MBA, Professor, Department of Otolaryngology-Head and Neck Surgery, University of Colorado School of Medicine Author and Editor Disclosure Synonyms and related keywords: cancer of the tonsil, head and neck metastatic carcinoma, tonsil cancer, palatine tonsil, faucial tonsil, tonsillar malignancy, cystic neck metastasis, squamous cell carcinoma, lymphoma of the tonsils INTRODUCTIONSection 2 of 9
  Many different types of malignancies can occur in tonsillar tissue, which is rich in lymphatics, blood vessels, muscle, nearby nerve fibers, and epithelium. All of these are potential sources of malignancy. However, only 2 primary tonsillar lesions are of any public health significance. The rarities are obviously important to the patient and the family and physicians who care for individuals with such conditions. Unfortunately, the rarity of these neoplasms precludes any meaningful data regarding behavior, treatment, risk factors, and prognostication. This being the reality, only the 2 most common primary tonsillar malignant neoplasms are discussed in this article, along with a brief discussion of metastatic lesions. FrequencyMalignancy of the tonsils is an uncommon entity that accounts for little more than 0.5% of new malignancies in the United States every year. The most important malignancies of the tonsils, from a numerical standpoint, include squamous cell carcinoma and lymphoma. Squamous cell carcinoma The Armed Forces Institute of Pathology (AFIP) registry from 1945-1976 determined that more than 70% of malignancies in this region are squamous cell carcinoma. Squamous cell carcinomas are about 3-4 times more common in men than in women, and they are largely tumors that develop in the fifth decade of life or later. Lymphoma Lymphomas of the tonsil are the second most frequent malignancy in this area. These account for roughly any malignant neoplasms that are not squamous cells. Of course, rarities exists, such as sarcomas and metastatic disease, but these are far down on the list of likely malignant tonsillar neoplasms. EtiologySquamous cell carcinoma According to the National Cancer Institute, accepted risk factors for squamous cell carcinoma include smoking and ethanol abuse. More recently, however, some indications show that viral etiology should also be considered. Although Epstein-Barr virus (EBV) is a major consideration in nasopharyngeal carcinoma, human papilloma virus (HPV) has been shown as more of a menace in this region. Some studies have identified indications of HPV presence in approximately 60% of tonsillar carcinomas. When the tonsils are included in studies of the entire oropharyngeal region, the risk factors include the following:
Lymphoma Currently, no general risk factors or causes of lymphoma are accepted. ClinicalPatients with tonsillar carcinomas may present with a neck mass. This is because carcinomas arise deep within the aforementioned crypts. These are deep epithelial invaginations of the surface epithelium. A squamous carcinoma may originate at 1 or more sites within the deep nests or branches within the tonsil. In addition, the tonsil can enlarge considerably, bulging into empty oral space before it causes alarm to the individual. Finally, the tonsils are lymphoid rich and contain abundant lymphatics that help the neoplasm access and metastasize to neck nodes. All of these factors, and perhaps other unknown ones, explain why patients may present with a neck mass. One of the unusual aspects of the neck node metastasis is the fact that a very large number of these are cystic. This has led to many being erroneously called branchial cleft carcinomas. In fact, the literature debates the existence of such an entity as a branchial cleft carcinoma (Soh, 1998). Many pathologists feel that branchial cleft carcinoma is actually either a metastasis or a direct extension from a tonsil squamous cell carcinoma. Regardless, cystic neck lymph node with an occult primary tumor must prompt an investigation of the tonsil. Occult primary squamous cell carcinomas that manifest as neck lymphadenopathy are a common problem faced by otolaryngologists. Although the hypopharynx and the nasopharynx are often suspected as being the seed area, the tonsil and the tongue base are also very likely (perhaps more likely) sites and should also be promptly investigated. In addition to a neck mass presentation, usually in the jugulodigastric region, other symptoms and signs may develop. These may be in conjunction with a neck mass or may be the only presentation. Sore throat, ear pain, foreign body or mass sensation, and bleeding are all possible. Trismus is an ominous sign because it probably indicates involvement of the parapharyngeal space. Such tumors may be large enough to involve or encase the carotid sheath. In addition, the tumor may extend to the skull or mediastinum. Even if the neck mass is not evident on casual inspection, careful palpation may reveal cervical lymphadenopathy. If the tumor has involved the tongue base, contralateral nodes may be involved. Primary tonsillar tumors may grow entirely beneath the surface. The clinician may therefore see nothing suspicious or may see only a slight increase in the size of the tonsil or the firmness of the area. Alternatively, an exophytic fungating mass with central ulceration and heaped-up edges may be present. It may be deep red to white. Cutting into the lesion during biopsy may demonstrate a gritty texture (a function of the degree of keratinization), a firm resistance (a function of the degree of fibrosis), and cystification (a function of necrosis). Obviously, these findings vary depending on the specifics of the tumor according to the parameters parenthetically described. The constitutional signs and symptoms of weight loss and fatigue are not uncommon with this neoplasm. RELEVANT ANATOMYSection 3 of 9
Although other anatomic sites also carry the term tonsil, including the lingual tonsil and pharyngeal tonsil (adenoid), this article focuses on the so-called faucial or palatine tonsil. The anatomy of the tonsillar area is responsible for the fact that the vast majority of malignant tumors in this region present in advanced stages. In addition, the tonsils themselves have ill-defined boundaries that merge with other anatomic landmarks. Often, tumors involve these areas by the time a tonsillar primary tumor is palpable. A primary tonsillar malignancy that involves the base of tongue or palate is not unusual. The anterior border of the tonsil is the anterior faucial pillar, which contains the palatoglossal muscle and is covered by squamous mucosa. The posterior border of the tonsil is the posterior faucial pillar, which contains the glossopharyngeal muscle and is covered by squamous epithelium. Occasionally, the ciliated columnar epithelium is also contained. Superiorly, these areas merge into the soft palate. Inferiorly, the pillars merge at the base of the tongue. No truly medial margin exists because this is an anatomic space at the junction of the oral cavity and pharynx. The lateral border is the pharyngeal soft tissue. The small indentation between the 2 pillar boundaries is the glossopharyngeal sulcus lined by squamous epithelium that dives deeply into the lymphocyte-rich tissue as deep crypts and tunnels. The arrangement of the epithelium with the lymphocytes in the tonsil is unusual. No clear-cut, sharply defined boundary of the epithelial cells and the lymphocytes exists. An admixture of the 2 cell types is found in many areas, with small ill-defined nests of epithelium with apparently percolating lymphocytes within these nests. This makes well-differentiated carcinoma difficult to determine because normal crypts have similar architectural appearances. Therefore, extreme caution in diagnosing well-differentiated squamous cell carcinoma of the tonsil is imperative. The cytology of the epithelial cells must be carefully considered. The crypt architecture may also be helpful, but only extremely experienced pathologists find this feature of much help. Another diagnostic error to avoid is the overcalling of mucoepidermoid carcinomas in this area. Small mucous-type glands are present in the tonsillar tissue and around its periphery. Because carcinoma arises deep in the crypts, they tend to grow extensively in a submucosal manner. Therefore, they often involve the mucus glands secondarily and appear as a neoplasm with both squamoid and glandular elements. In fact, most so-called mucoepidermoid carcinomas of this area are simply squamous cell carcinoma. CONTRAINDICATIONSSection 4 of 9
No contraindications exist. WORKUPSection 5 of 9
Lab Studies
Imaging Studies
Diagnostic Procedures
Histologic FindingsSquamous cell carcinoma Most palatine tonsil squamous cell carcinomas are moderately to poorly differentiated. The following variants, although essentially squamous cell carcinomas, in this area have been described with some frequency:
Lymphomas In terms of the frequency of primary malignancies, lymphomas are second to squamous cell carcinomas. Because of the richness of lymphoid tissue in this area, all of the Waldeyer ring, the lingual tonsil, the nasopharynx, and the tonsils are frequent sites of lymphoma. Most tonsillar lymphomas are diagnosed during the sixth and seventh decades of life; however, tonsillar lymphomas affect a wide age range, and tonsillar lymphoma should be in the differential diagnoses of tonsillar masses, regardless of age. Tonsillar lymphomas usually present as a painless mass in the tonsil, although sore throat is not uncommon. On occasion, otalgia is the presenting symptom. Lymphoma type determination is crucial and can be achieved only with the help of special studies obtained by the pathologist. The cell and tissue markers used to type lymphomas are quite sensitive. These require fresh frozen tissue and unusual fixatives, in addition to immunohistochemical stains. The quality of these studies is time dependent. Immediate examination of newly removed tissue by the pathologist is essential, if possible. The pathology staff should be alerted at least 24 hours in advance that a possible lymphoma is undergoing biopsy. Some fixatives may not be readily available, and liquid nitrogen for fresh frozen tissue should be made accessible. All of these may take some time. A one-day notice should ensure that proper handling is performed as soon as possible. All of these studies help in the crucial determination of lymphoma type. Many require fresh or frozen tissue for immunohistochemical studies. Most tonsillar carcinomas are diffuse non-Hodgkin large B-cell lymphomas. Mucosa-associated lymphoid tissue (MALT) low-grade B-cell lymphomas composed of small cells are uncommon in the tonsil. This is surprising because the tonsil consists of a very intimate intermingled arrangement of epithelium and lymphocytes, which, in theory, would make an ideal environment for the development of MALT lymphomas. In reality, they are so uncommon in this region that they are case reportable. Metastatic lesions to the tonsil Although the palatine tonsils are a rich source of lymphatics and lymphoid tissue, metastases to the palatine tonsils are rare. Case reports have described an extraordinarily wide spectrum of malignancies metastatic to this area. Breast, various lung primaries, renal carcinomas, and pancreatic and colorectal malignancies have been reported. Documented cases of Wilms tumor and choriocarcinoma metastasizing to this distant site also exist. StagingIn addition to cell typing and establishing a differentiation status of the tumor, both accomplished by the pathologist after biopsy, the extent or stage of the tumor is evaluated. Before any prognostication or treatment options are considered, including clinical trial eligibility, the American Joint Committee on Cancer (AJCC) guidelines should be checked through the National Cancer Institute. To establish the proper stage, the following checklist should be used to ensure that complete information is obtained efficiently:
The 4 main stages are I, II, III, and IV. Stage IV is subdivided into types A, B, and C. To obtain as much information as possible prior to therapy, a thorough clinical examination, physical examination, and appropriate imaging studies are necessary. Plain radiograph films are useful for the study of metastatic disease, especially to the lungs. CT scans, both with and without contrast, have a role, as does MRI. These are useful in the evaluation of the soft tissue extent of the tumor, as well as the assessment of the lymph node status. TREATMENTSection 6 of 9
Medical therapyThe treatment depends on the tumor stage. Surgery is a mainstay for resectable tumors; however, this is frequently followed by radiation. Treatment includes the neck for any tonsillar carcinoma. Depending on the radiologic findings, this may mean a neck dissection or radiation. Chemotherapeutic modalities should be strongly considered in unresectable tumors. In addition, many chemotherapeutic trials are in progress; searching out any that may apply to the individual patient is prudent. To summarize, treatment of tonsillar squamous cell carcinomas is complicated and must be individualized to the patient. The disease carries a 30% probability of the development of a second primary tumor. Therefore, follow-up is necessary, as is the careful consideration of initial therapy. The disease, as well as the treatment options, both carry considerable morbidity. Many experienced oncologists believe that tonsillar squamous cell carcinoma of any grade is more radiosensitive than comparable tumors in other head and neck locations. However, radiation should always be used with the knowledge that recurrence rules it out as a future option. Follow-upRoutine follow-up care of patients with tonsil cancer is important, particularly because the risk of developing a second primary tumor is highest in this group. Patients with head and neck cancers have a 20% overall risk of developing a second primary tumor, while patients with tonsil cancer have as high as a 30% risk. COMPLICATIONSSection 7 of 9
Complications of the various forms of current therapy include the following:
The family and patient should understand all of these in advance before committing to any therapy. OUTCOME AND PROGNOSISSection 8 of 9
The prognosis as determined by 5-year survival rate of treated squamous cell carcinoma of the tonsillar region is as follows:
Some data suggest that patients treated for exophytic lesions tend to do a little better than patients treated for sessile lesions. REFERENCESSection 9 of 9
Malignant Tumors of the Tonsil excerpt Article Last Updated: Feb 14, 2007 |
