Is resection necessary in biopsy-proven asymptomatic pulmonary hamartomas?

A best evidence topic was written according to a structured protocol. The question addressed was: in surgically fit patients with biopsy-proven asymptomatic pulmonary hamartoma, is surgical resection superior to conservative watchful waiting in terms of outcome. A total of 460 papers were identified using the reported search, of which 9 represented the best evidence to answer the clinical question. The authors, date, journal, country, study type, population, outcomes and key results are tabulated. Three studies were observational following up biopsy-proven asymptomatic pulmonary hamartoma with no resection for a mean period up to 5 years (where mentioned). No patients developed new symptoms or malignant transformation. One of the three studies considered tumour growth in patients with pulmonary hamartoma to be slow with a mean expansion in transverse diameter of 3.2 ± 2.6 mm per year. There were five sizable retrospective studies and one observational study for resection of pulmonary hamartoma. Three of the six studies showed no postoperative mortality but there was an association with major resection (lobectomy/pneumonectomy) ranging from 10 to 14%. There was no tumour recurrence during a long follow-up period in the three studies. One other study had a 4% postoperative mortality rate and a 1.8% postoperative lung cancer developing rate during a follow-up period of 61 months with a consequent recommendation against surgery in asymptomatic patients. In another study, there was a 2.6% recurrence rate after surgical resection during a follow-up period of 7.3 years whereas in the final observational study, 3 patients developed a malignant lung lesion during a follow-up period of 2-10 years after resection and in the same area from where the hamartoma was excised. In conclusion, we would recommend surveillance, rather than resection, of patients with biopsy-proven asymptomatic pulmonary hamartomas, since there is no evidence of malignant transformation during follow-up in any study. Resection is usually safe but a significant number of patients need a major resection (lobectomy or pneumonectomy, 10-14%) for clearance. Diagnosis can be achieved by a combination of radiological evidence and fine needle biopsy (sensitivity 85-90%). Therefore, resection should be reserved for symptomatic patients, or where the diagnosis remains in doubt.