Non-imaged pulmonary nodules discovered during thoracotomy for metastasectomy by lung palpation

Video-assisted thoracoscopic surgery (VATS) is an increasingly used technique to treat patients with pulmonary metastases, but it does not usually afford lung palpation.

A retrospective study on patients with lesions defined as 'VATA-able' who underwent open metastasectomy via thoracotomy. All patients underwent 64-slice helical CT scan with intravenous contrast using 5mm cuts and integrated FDG-PET/CT. Unsuspected malignant pulmonary nodules that were palpitated and removed, and were not imaged pre operatively were defined as 'malignant nodules' and would have been missed by VATS metastasectomy.

From January 2004 to December 2005, 57 patients had 'VAT-able' metastatic pulmonary lesions that were resected via thoracotomy by one thoracic surgeon. Twenty-one (37%) patients had non-imaged pulmonary nodules that were discovered only by bi-manual palpation and would have been missed by VATS metastasectomy, but these nodules were only malignant in 10 (18%) patients. The median size of the non-imaged pulmonary nodule was 0.7cm (range, 0.4-0.8cm). Colorectal carcinoma was the most common tumor requiring metastasectomy. Non-imaged malignant pulmonary nodules were most frequently found in patients with leiyomyosarcoma and osteosarcoma (three of eight patients in both).

Metastasectomy via open thoracotomy, which affords bi-manual lung palpation of the entire ipsilateral lung, may discover non-imaged malignant pulmonary metastases in 18% of patients who have had a previously treated solid organ cancer and have at least one imaged metastatic lesion in the lung. The clinical impact of these findings is unknown. A prospective study to further examine this issue is underway.