Unknown Case of the Month #95 |
| Findings: The esophogram show abrupt narrowing of the mid esophagus at the level of the subcarinal lymph nodes. There is also complete opacification of the right hemithorax from a prior pneumonectomy for lung cancer. A PET scan, shown below, demonstrates hypermetabolic activity in the subcarinal lymph nodal region as well as in metastasis in a left supraclavicular lymph node and the left upper lobe.
Diagnosis: Lung cancer with metastasis involving the esophagus Metastasis to the esophagus occurs in approximately 3% of patients dying from malignancy. This percentage is as high a 9% in women dying from breast cancer (mean age from mastectomy to dysphagia = 7.1 years). Three general mechanisms have been observed: direct invasion, contiguous involvement from regional lymph nodes, and hematogenous spread. Direct extension from malignancies of the stomach, lung, thyroid, hypopharynx and larynx usually simulates a primary esophageal carcinoma on an upper GI series. Malignant mediastinal nodes, especially in the subcarinal nodal area, are most commonly due to lung and breast carcinoma. Metastatic breast carcinoma often in particular often causes a fibrotic reaction that may result in a long smooth narrowing, similar to treated lymphoma or mediastinal fibrosis. Hematogenous spread is the most unusal form of metastasis to the esophagus and is may be secondary to melanoma or cancer of the liver, pancreas, prostate, and testes. Once again the metastasis may simulate a primary esophageal lesion. Similar to lymphoma, hematagenous metastasis are often much larger than one would surmise from the patients dysphagia. FDG PET has shown a significant improvement vs. CT in the staging of lung cancer, with a pooled sensitivity of 84% and a specificity of 89% (positive predictive value = 79%, negative predictive value = 93%). Endoscopic biopsy may be necessary to establish the correct diagnosis, but can be falsely negative if the underlying esophageal mucosa is preserved. References: Anderson MF, Harell GS. Secondary esophageal tumors. AJR 1980; 135:1243-1246. Fisher MS. Metastasis to the esophagus. Gastrointest Radiol 1976; 1:249-251.
Sharma A, Fidias P, Hayman LA, et al. Patterns of lymphadenopathy in
thoracic malignancies. Dr.
Lawrence C. Swayne, Attending Back to Case of the Month Archive |
