Pulmonary Metastases
Criteria for pulmonary metastatectomy, operative approach, and outcomes by tumour histology.
Overview
The lung is the most common site of haematogenous metastasis. Up to 30% of all cancer patients develop pulmonary metastases during the course of their disease. Pulmonary metastatectomy — surgical removal of lung metastases — can offer long-term survival or even cure in highly selected patients.
Criteria for pulmonary metastatectomy
Patient selection is the critical determinant of outcome. All criteria must be met simultaneously:
- Primary tumour completely controlled (resected or in remission)
- No extrapulmonary metastases (or extrapulmonary disease also resectable)
- Complete resection of all pulmonary metastases technically feasible
- Adequate cardiopulmonary reserve to tolerate planned resection
- No superior alternative systemic therapy available
Complete (R0) resection of all pulmonary metastases is the primary determinant of survival after metastatectomy — more important than number of metastases, laterality, or histology. A technically complete resection should not be compromised for any of these factors.
Pre-operative workup
- CT chest — characterise all lesions; thin-section CT is more sensitive than PET for small nodules
- PET-CT — exclude occult extrapulmonary disease
- Tissue diagnosis of at least one lesion — where primary is uncertain or long disease-free interval makes recurrence less certain
- Pulmonary function tests and functional assessment
- Multidisciplinary team review — essential; systemic therapy options must be considered alongside surgical candidacy
Operative approach
Preferred for peripheral lesions amenable to wedge resection. Reduced morbidity. May miss small nodules not visible on pre-operative CT — manual palpation of the deflated lung is not possible.
Allows bimanual palpation of the deflated lung — detects nodules not visible on CT. Preferred when complete resection requires manual palpation to find all disease.
For bilateral synchronous metastases. Allows bilateral exploration and resection at one sitting. Limited access to lower lobes and posterior segments.
Resection type: Parenchyma-preserving wedge excision is preferred — lobectomy only if the metastasis involves the hilum or wedge excision cannot achieve clear margins. Pneumonectomy for metastases carries very high morbidity and poor survival — rarely indicated.
Repeat pulmonary metastatectomy is appropriate in patients who satisfy the same criteria as initial surgery — controlled primary, no extrapulmonary disease, complete resection feasible, and adequate reserve. Outcomes are comparable to initial metastatectomy in well-selected patients.
Prognostic factors and outcomes
| Favourable | Equivocal | No significant impact |
|---|---|---|
| Complete R0 resection*** | Number of nodules | Age / sex |
| Longer disease-free interval | Histology | Unilateral vs bilateral |
| N stage | Wedge vs lobectomy |
| Primary tumour | 5-year survival after metastatectomy |
|---|---|
| All histologies | 25–40% |
| Colorectal carcinoma | 40–45% |
| Renal cell carcinoma | 13–54% |
| Breast | 35–50% |
| Germ cell tumour | 68% |
| Soft tissue sarcoma | 20–40% |
All clinical content should be verified against current guidelines before clinical application. This resource is intended for revision and educational purposes only.
Standard textbooks
- Shields TW, LoCicero J, Reed CE, Feins RH. General Thoracic Surgery. 7th ed. Lippincott Williams & Wilkins.
- Sellke FW, del Nido PJ, Swanson SJ. Sabiston & Spencer Surgery of the Chest. 9th ed. Elsevier.
- Pearson FG, et al. Thoracic Surgery. 3rd ed. Churchill Livingstone.