Chest wall implantation of thymic cancer after computed tomography-guided core needle biopsy.

Percutaneous core needle biopsy is a useful procedure for diagnosing lung and mediastinal tumors. However, it has the potential to spread malignant cells from the tumor to the chest wall and pleural cavity. We report the case of a patient with thymic cancer who developed a metastatic tumor at the transthoracic needle biopsy site following a curative resection. The patient underwent an additional chest wall resection, but she developed recurrence in the pleural cavity 1 month after the second operation. The risk of tumor implantation and the related complications that can occur with transthoracic needle biopsy should be considered in patients with a malignant tumor. The indications for transthoracic needle biopsy should be restricted.