CHEST-X-RAY - ROUTINE INDICATION IN THE FOLLOW-UP OF DIFFERENTIATED THYROID-CANCER

Aim: This retrospective study sought to elucidate whether routine ches t x-ray is still useful for detection of pulmonary metastases in low r isk patients despite the high sensitivity of the tumor marker thyroglo bulin. Method: The hospital files of 609 patients with well-differenti ated thyroid cancer were analysed. Pulmonary formation of metastases w as diagnosed in 50 patients. The thyroglobulin value at the time of di agnosis was compared with the chest x-ray findings and, if present, ad ditional diagnostic information such as iodine-131 whole body scintigr aphy (WBS) and thorax CT. Results: The sensitivity of the chest x-ray to detect pulmonary metastases was at 52% lower than that of WBS (64%) , thorax CT (82%) and thyroglobulin during suppression therapy (86%). Among the patients with papillary carcinoma stage I and II (UICC 1987) , only 1 patient developed pulmonary metastases during follow up. In t his low risk group of patients, detection of lung metastases exclusive ly by chest x-ray, without elevation of thyroglobulin level is extreme ly rare (calculated probability 1/4000) and associated with considerab le costs. Conclusion: Routine, life long chest x-ray in low risk patie nts without a suspected recurrence (e.g. positive thyroglobulin) needs to be reconsidered.