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© BMJ Publishing Group Limited 2023. No commercial reuse. See rights and permissions. Published by BMJ. DESCRIPTION A female patient in her early 50s with left renal mass was treated with complete nephrectomy. Pathology revealed pT2N0 clear cell renal cell carcinoma (ccRCC) and there was no evidence of any distant metastasis at the baseline staging CT scan. The surveillance CT scan in 12month time revealed two small pulmonary nodules in the lower lobes (figure 1A,B). A percutaneous CTguided biopsy of the largest pulmonary nodule in the left lower lobe was performed, confirming lung metastasis from renal cell carcinoma. The patient was admitted in our hospital for further management. The patient with ECOG performance status of 0 was discussed in our local multidisciplinary team (MDT) with the decision of locoregional treatment of the two pulmonary metastases in order for the patient as an M1 with no evidence of disease to receive adjuvant pembrolizumab as the standard for care treatment. The lung metastasis with more central location in the left lower lobe was ablated with microwave technique under CT guidance and the peripheral subpleural metastatic lesion in the right lower lobe was treated with surgical wedge resection (figure 1C–E). The followup CT scans in 3, 6 and 12 months did not show any signs of recurrence at the sites of thermal ablation and surgical resection or new sites of disease. Approximately 30% of patients with RCC have metastatic disease at the time of the diagnosis with lung parenchyma being the most common site of metastasis. 2 Oligometastatic disease is defined as a metastatic disease that is limited up to five metastatic lesions where all metastatic sites can be safely treated. 4 Treatment options in oligometastatic disease include systemic therapy and metastasectomy with or without stereotactic body radiation therapy or ablative techniques. Pulmonary metastasectomy is the established treatment that can provide improved longterm survival in patients with metastatic lung disease. MDT discussion is necessary to guide individualised surgical management of pulmonary metastasis in view of surgical extent and pulmonary resources. Surgical wedge or sublobar resection represents the treatment of choice for the excision of small metastatic lesions. However, complete surgical metastasectomy in bilateral disease is not always feasible, especially in more centrally located lung lesions which require more extensive surgical resection compromising pulmonary function. As cumulative parenchymal loss should be considered, metastasectomy with lung parenchyma sparing techniques is preferable to preserve pulmonary tissue, pulmonary function and especially in case of future pulmonary lesions and resections. Percutaneous CTguided ablation of lung metastasis has been demonstrated as a safe and Figure 1 (A,B) Axial CT images show two small metastatic lung nodules in the left and right lower lobes with deep and subpleural location measuring 7 and 4 mm, respectively (circles), that is, deep and subpleural location of the left and right lower lobe metastatic nodules, respectively. (C) Microwave ablation of the left lower lobe metastasis. Intraprocedural axial CT image with maximum intensity projection reconstruction demonstrates the correct probe position. (D) Twentyfour hours post ablation. Axial CT image shows the expected postablation changes with increase in size of the treated area at the site of the metastatic nodule with a reverse halo sign pattern. (E) Postsurgical axial CT image shows focal atelectatic changes in the right lower lobe following wedge resection and decrease in size of the ablation zone in the left lower lobe 3 months following thermal ablation.