METASTATIC PAPILLARY THYROID-CARCINOMA TO LUNG DIAGNOSED BY BRONCHOALVEOLAR LAVAGE

The diagnosis of papillary carcinoma of the thyroid metastatic to the lung frequently requires a battery of noninvasive tests. Occasionally, invasive procedures such as open lung biopsy, transthoracic needle bi opsy, and transbronchial lung biopsy are employed to confirm the diagn osis. A 31-yr-old woman with papillary thyroid carcinoma treated previ ously by a near-total thyroidectomy and I-131 ablation presented to ou r clinic with shortness of breath and a clear chest roentgenogram. A p ost-I-131 treatment whole body scan revealed widespread I-131 pulmonar y uptake, and the presence of papillary thyroid cancer was confirmed b y bronchoalveolar lavage. We conclude that bronchoalveolar lavage shou ld be considered when tissue confirmation of metastatic papillary carc inoma to the lung is needed. During the evaluation and follow-up of th is patient, we were able to determine that metastatic papillary carcin oma to the lung may cause a methacholine bronchoprovocation test to be falsely positive for asthma.