Introduction
Background
Primary esophageal lymphoma is a rare occurrence, with fewer than 25 cases reported in the past 25 years. In a series of 1467 cases of GI lymphoma, primary esophageal lymphoma accounted for only 3 cases. In general, involvement of the esophagus is most commonly a result of contiguous spread from the proximal stomach, adjacent mediastinal lymph nodes, or cervical lymph nodes. Persons with the disorder have varying presentations and relatively poor prognoses. Since the advent of HIV infection/AIDS, esophageal lymphoma has become an important, though still rare, part of the differential diagnosis in immunosuppressed patients presenting with symptoms referable to the esophagus.
Pathophysiology
The diagnosis of esophageal lymphoma is divided into 2 categories based upon site of origin. Most lymphomas involving the esophagus are thought to represent secondary involvement by an adjacent site. In most cases, esophageal lymphomas involving the distal esophagus represent extension from the proximal stomach. Lymphomas arising in the middle third of the esophagus may be secondary to mediastinal lymph node enlargement with involvement of the esophagus. A third site of involvement is the proximal esophagus, which may represent extension from adjacent cervical lymph nodes.
The etiology of primary esophageal lymphoma is unknown; however, HIV infection is a risk factor for its development. The initial site of lymphomatous involvement in primary esophageal lymphoma is submucosal lymphoid patches, which then extend to involve the mucosa. Additionally, prior exposure to Epstein-Barr virus (EBV) may play some role in the development of esophageal lymphoma.
Dawson et al developed the following 5 criteria needed to identify a primary GI lymphoma1 :
- No palpable superficial lymph nodes
- Normal chest radiograph findings with no evidence of lymphadenopathy
- Normal WBC count
- Predominant lesion within the GI tract with lymph node involvement confined to the lymph node chain involved in drainage of that specific GI segment
- No involvement of the liver or spleen
Frequency
United States
GI tract lymphoma is fairly common, comprising approximately 10% of all lymphomas. In non-Hodgkin lymphoma, the most common extranodal site is the GI tract, which is involved in 5-20% of patients during life and up to 50% of patients at autopsy. The most common GI sites for lymphoma are the stomach (48-50%), small bowel (30-37%), and ileocecal region (12-13%). The esophagus is the least common site of involvement, with less than 1% of patients with GI lymphoma presenting with esophageal involvement.
Mortality/Morbidity
The data regarding prognosis of GI lymphoma indicate a variable mortality rate. Prognosis depends on the stage of disease at diagnosis and the feasibility of surgery or chemotherapy. Mortality also depends on the underlying health of the patient, as demonstrated by the overall poor prognoses of patients who are infected with HIV. The presence of AIDS, a CD4 count of less than 100/µL, and a low Karnofsky score are associated with a poor prognosis. Better outcomes are associated with a good performance status, an absence of opportunistic infections, and a CD4 count of greater than 100/µL. Additionally, patients with T-cell lymphoma have higher rates of esophageal perforation and poorer overall survival rates as compared with those patients demonstrating a B-cell phenotype.
Sex
Because of the extreme rarity of esophageal lymphoma and the small number of reported cases, a trend cannot be established regarding which sex is most commonly affected. In one series, 12 of 17 patients were men. In another report of patients with HIV-associated esophageal lymphoma, the patients were typically 40-year-old men who were profoundly immunosuppressed. A final series of 6 cases of primary esophageal lymphoma included 5 men and 1 woman.
Age
The age at presentation of esophageal lymphoma is highly variable, with cases reported in patients as young as 17 years and as old as 86 years. One case series that evaluated 763 patients infected with HIV, 22 of whom presented with non-Hodgkin lymphoma, revealed a mean age of 38.8 years ± 7.8 (SD). Half of these patients had GI involvement, and 2 had esophageal involvement. In one series, patients with primary esophageal lymphoma not associated with HIV infection/AIDS tended to be older (mean age, 61 y) than those in the HIV infection/AIDS associated group (mean age, 40 y).
Clinical
History
Symptoms can include dysphagia (most common), odynophagia, weight loss, chest pain, fever, fatigue, abdominal pain, and hoarseness. Patients may present with a history consistent with secondary achalasia. Patients do not typically present with fever or night sweats (B symptoms).
- Invasion of the esophagus may result in hemorrhage, obstruction, or perforation with a tracheoesophageal fistula.
- Esophagotracheal fistulae most often result in death secondary to aspiration pneumonia. Even when surgically repaired, such fistulae are likely to recur.
- Patients with HIV/AIDS
- In patients with HIV, consider underlying esophageal lymphoma in a clinical presentation consistent with infectious esophagitis not responsive to adequate therapy. This is especially true when esophageal ulcerations are present.
- In patients with HIV, consider underlying esophageal lymphoma in a clinical setting consistent with idiopathic esophageal ulceration not responsive to oral steroid therapy.
- Most patients who are known to have AIDS prior to diagnosis of esophageal lymphoma have a history of opportunistic infections, such as those caused by Pneumocystis carinii (eg, P carinii pneumonia), Candida species, cytomegalovirus, and herpes simplex virus.
Physical
- Physical examination is generally not helpful in diagnosing esophageal lymphoma.
- Ten cases of esophageal lymphoma in patients without HIV have been reviewed.
- Nine of these 10 patients appeared to have primary esophageal lymphoma.
- One of these 9 patients was found to have mild anemia; otherwise, all physical examination findings were reported as normal.
- Cervical lymphadenopathy was a prominent finding of the physical examination of the sole patient who appeared to have esophageal involvement of a previously diagnosed non-Hodgkin lymphoma.
- Physical examination appears to be most useful in excluding generalized peripheral lymphadenopathy, which, by definition, should not be present in primary esophageal lymphoma.
Causes
The etiology of primary GI lymphoma is unknown.
- HIV infection/AIDS: HIV infection has been recognized as a risk factor for the development of primary GI lymphoma; the relative risk of developing non-Hodgkin lymphoma for persons infected with HIV is 104 times that of people who are not infected with the virus.
- Epstein-Barr virus
- Most of the GI tract lymphomas are of the B-cell type; however, the significance of the EBV as an etiologic factor is controversial.
- Although EBV is strongly related to B-cell proliferation in Burkitt lymphoma, its exact role in GI lymphoma is unknown.
- Oncogenes: DNA probes have found the proto-oncogene C-myc transcription in 75% of AIDS-associated lymphomas, which suggests a role for the C-myc oncogene.
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