Discussion
Diagnosis With Brief Discussion
- Diagnosis
- Metastasis from thyroid cancer.
- Radiologic Findings
- Right thyroid lobectomy state is seen on CT (Figure 1). The prevascular LN is enlarged and heterogeneously enhanced (Figure 2). A lobular and elongate mass is involving both the lung parenchyma and right bronchus intermedius, which protrudes into bronchial lumen. In the collapsed right middle lobe, fluid-filled and dilated bronchi are seen (Figure 3-4).
- Brief Review
- Endobronchial metastases from nonpulmonary tumors are uncommon. The frequences of endobronchial metastasis are variable by definition, ranging from 2-50% of pulmonary metastases from extrathoracic neoplasm. One definition includes only direct metastasis to the tracheobronchial wall, and the other includes the secondary involvement as well as direct invasion.
A variety of tumors, breast, colorectal, renal, ovarian, thyroid, uterine, testicular, nasopharynx, prostate, and adrenal carcinomas; sarcomas; melanomas; and plasmacytomas has been associated with endorbonchial metastasis, although breast, colorectal, renal carcinomas predominate.
Patients histologically diagnosed as having endobronchial metastases were retrospectively evaluated and it was found that endobronchial metastases can be asymptomatic and diagnosed simultaneously, and that upper lobe involvement and lymphocytic inflammation predominate (1).
The metastases may occur directly onto the bronchial wall, or may occur initially in the lymph nodes or lung parenchyma around the bronchus and then invade through the bronchial wall.
The former occurrence is less frequent. Kiryu et al . (2) described four types of developmental modes for EBM: type I, direct metastases to the bronchus; type 2, bronchial invasion by a parenchymal lesion; type 3, bronchial invasion by mediastinal or hilar lymph nodes; and type 4, peripheral lesions extending along the proximal bronchus. Both direct (27.7%) and indirect involvement of bronchus were detected.
It is important to make a distinction between EBM and primary lung cancers and benign lesions, as treatment approaches will differ. An exact histological diagnosis needs to be established in each patient.
Some cases of endobronchial metastases from papillary or follicular thyroid cancer manifested with hemoptysis were reported (3, 4).
- References
- 1, Dursun AB, Demirag F, Bayiz H, Sertkaya D. Endobronchial metastases: a clinicopathological analysis. Respirology 2005;10:510-514.
2, Kiryu T, Hoshi H, Matsui E et al. Endotracheal/endobronchial metastases: clinicopathologic study with special reference to developmental modes. Chest 2001; 119:768-775.
3, Ulger Z, Karaman N, Piskinpasa SV, Niksarlioglu YO, Kilickap S, Erman M, et al . Endobronchial metastasis of thyroid follicular carcinoma. J Natl Med Assoc 2006;98: 803-806.
4, Nomori H, Horio H, Mimura T, Morinaga S. Massive hemoptysis from an endobronchial metastasis of thyroid papillary carcinoma. Thorac Cardiovasc Surg. 1997; 45:205-207.
- Keywords
- airway, malignant tumor, metastasis,