Natriuretic peptides and mortality in community-acquired pneumonia.

We thank Dr Senthi and colleagues for their interest in our CHEST article. 1 We agree that the work by Haasbeek et al 2 should have been cited in our article. Although the median follow-up of 16.5 months is rather short, the results are impressive with no local failures and only two of 15  grade 3 lung-associated toxicities. We agree that stereotactic radiotherapy (SRT) is a less invasive procedure in comparison with cryoablation, particularly if it is done without the implantation of fi ducial markers. In terms of safety, pneumothorax after cryoablation can be suffi ciently managed by course observation, by chest tube insertion, or, if persistent, by medical pleurodesis. However, in single-lung patients, delayed pneumothorax may have serious consequences if access to medical facilities is limited. We have previously reported that the incidence of delayed pneumothorax after cryoablation occurred in 30 of 193 patients (16%), mostly at 3 days after cryoablation still during admission. However, the incidence could occur as late as 20 days after cryoablation, and eight of these patients were readmitted after being discharged. Therefore, if the incidence of pulmonary toxicities after SRT is actually as low as generally reported ( grade 2, 5%  10%), we agree that SRT should be offered as a primary treatment option even in single-lung patients. However, one concern remains. To date, SRT for lung cancer has been evaluated mostly in inoperable patients, many with COPD. A recent report suggests that radiation pneumonitis may be milder in patients with COPD in comparison to patients with normal lung function. 3 Another study shows that the decline in pulmonary function after SRT was less in patients with COPD in comparison to patients who underwent SRT primarily because of cardiac comorbidities. 4 In a study of SRT in medically operable patients with lung cancer, grade 3 pulmonary toxicity was noted in only one patient (1.1%), but this was a retrospective study, and 38 of 87 patients in this study had underlying chronic lung diseases. 5 The majority of patients in the study by Haasbeek et al 2 were also patients with COPD. Therefore, we consider that the incidence of pulmonary toxicities after SRT in patients with normal lung function is still unclear. Ongoing prospective studies on SRT in patients with operable lung cancer with normal lung function will provide answers to this issue.