Spiral CT of the lung in children with malignant extra-thoracic tumors: distribution of benign vs malignant pulmonary nodules

The purpose of this paper is to clarify the distribution of benign vs malig nant pulmonary nodules which are seen on spiral CT in children with maligna nt extra-thoracic solid tumors. Seventy-four children with known solid, ext ra-thoracic tumors underwent spiral CT of the chest. According to the initi al and follow-up (interval 9.2 +/- 4.7 months) findings, the children were graded into four groups: I = normal; II = solitary nodule unchanged at foll ow-up; III = multiple nodules with one or more than one unchanged at follow -up, and IV = solitary or multiple nodules all changed at follow-up. Nodule s without change at follow-up were regarded as benign. Forty-nine children did present with normal pulmonary CT exams. In 7 cases solitary pulmonary n odules were found unchanged (group TI) at follow-up and in 2 cases (group I II) some of the nodules were stationary. Thus, 12% (9 of 74) presented with at least one pulmonary nodule that did not change at follow-up. Solitary n odules (in groups II and IV) with a diameter < 5 mm were in 70 % (7 of 10) unchanged at follow-up and regarded as benign. In children with known solid extra-thoracic turners at initial presentation, 70 % of solitary nodules ( < 5 mm) may be benign. 70 avoid overstaging, smaller solitary nodules must not automatically be regarded as metastases.