Pulmonary function studies in children treated by chemoradiotherapy and stem cell transplantation

Pulmonary function as a continuum of risk: critical care utilization and survival after allogeneic hematopoietic stem cell transplantation - a multicenter cohort study

Abnormal pre-transplant pulmonary function tests (PFTs) are associated with reduced survival after allogeneic HCT. Existing scoring systems consider risk dichotomously, attributing risk only to those with abnormal lung function. In a multicenter cohort of 1717 allo-HCT recipients, we examined the association between pre-transplant PFT measures and need for ICU admission (120d), frequency of mechanical ventilation (120d) and overall survival (5 y). Predictive models were developed and validated using Cox proportional hazards, incorporating age, FEV1 (forced expiratory volume in 1-second) and diffusing capacity (DLCO). In univariate analysis, hazard ratios for each outcome (95% CI) were: mechanical ventilation (FEV1: 0.60 [0.52-0.69], DLCO: 0.69 [0.61-0.77], p < 0.001), ICU admission (FEV1: 0.74 [0.67-0.82], DLCO: 0.79 [0.72-0.86], p < 0.001) and overall survival (FEV1: HR 0.87 [0.81-0.94], DLCO: 0.83 [0.77-0.89], p < 0.001). A multivariable Cox model was developed and compared to the HCT-CI Pulmonary score in a validation cohort. This model was better at predicting need for ICU admission and mechanical ventilation, while both models predicted overall survival (p < 0.001). In conclusion, the risk conferred by pre-transplant pulmonary function should be considered in a continuous rather than dichotomous manner. A more granular prognostication system can better inform risk of critical care utilization in the early post-HCT period.

Adjusting diffusing capacity for anemia in patients undergoing allogeneic HCT: a comparison of two methodologies

BACKGROUND

Diffusing capacity (DLCO) measurements are affected by hemoglobin. Two adjustment equations are used: Cotes (recommended by ATS/ERS) and Dinakara (used in the hematopoietic stem cell transplantation comorbidity index [HCT-CI]). It is unknown how these methods compare, and which is better from a prognostication standpoint.

STUDY DESIGN

This is a retrospective cohort of 1273 adult patients who underwent allogeneic HCT, completed a pre-transplant DLCO and had a concurrent hemoglobin measurement. Non-relapse mortality was measured using competing risk analysis.

RESULTS

Patients had normal spirometry (FEV1 99.7% [IQR: 89.4-109.8%; FVC 100.1% [IQR: 91.0-109.6%] predicted), left ventricular ejection fraction (57.2[6.7]%) and right ventricular systolic pressure (30.1[7.0] mmHg). Cotes-DLCO was 85.6% (IQR: 76.5-95.7%) and Dinakara-DLCO was 103.6% (IQR: 90.7-117.2%) predicted. For anemic patients (Hb<10g/dL), Cotes-DLCO was 84.2% (IQR: 73.9-94.1%) while Dinakara-DLCO 111.0% (97.3-124.7%) predicted. Cotes-DLCO increased HCT-CI score for 323 (25.4%) and decreased for 4 (0.3%) patients. Cotes-DLCO was superior for predicting non-relapse mortality: for both mild (66-80% predicted, HR 1.55 [95%CI: 1.26-1.92, p < 0.001]) and moderate (<65% predicted, HR 2.11 [95%CI: 1.55-2.87, p<0.001]) impairment. In contrast, for Dinakara-DLCO, only mild impairment (HR 1.69 [95%CI 1.26-2.27, p < 0.001]) was associated with lower survival while moderate impairment was not (HR 1.44 [95%CI: 0.64-3.21, p = 0.4]). In multivariable analyses, after adjusting for demographics, hematologic variables, cardiac function and FEV1, Cotes-DLCO was predictive of overall survival at 1-year (OR 0.98 [95%CI: 0.97-1.00], p = 0.01), but Dinakara-DLCO was not (OR 1.00 [95%CI: 0.98-1.00], p = 0.20).

CONCLUSION

The ERS/ATS recommended Cotes method likely underestimates DLCO in patients with anemia, whereas the Dinakara (used in the HCT-CI score) overestimates DLCO. The Cotes method is superior to the Dinakara method score in predicting overall survival and relapse-free survival in patients undergoing allogeneic HCT.

Lung Function Predicts Outcome in Children With Obstructive Lung Disease After Hematopoietic Stem Cell Transplantation

Obstructive lung disease (OLD) that develops after hematopoietic stem cell transplantation (HSCT) has a significant impact on morbidity and mortality. We investigated the role of pulmonary function tests (PFTs) in the prediction of prognosis of OLD in children who have undergone HSCT. We retrospectively reviewed 538 patients who underwent allogenic HSCT in the Department of Pediatrics, Seoul St. Mary's Hospital, South Korea, from April 2009 to July 2017. OLD was identified on PFTs or chest computed tomography scans obtained from 3 months after HSCT onwards. OLD developed after HSCT in 46 patients (28 male individuals, median age: 11.2 y). The group that developed OLD with an unfavorable prognosis (n=23) had a lower forced vital capacity (FVC) (% of predicted, 78.53±24.00 vs. 97.71±16.96, P=0.01), forced expiratory volume in 1 second (FEV1) (% of predicted, 52.54±31.77 vs. 84.44±18.59, P=0.00), FEV1/FVC (%, 59.28±18.68 vs. 79.94±9.77, P=0.00), and forced expiratory flow at 25% to 75% of forced vital capacity (FEF25-75) (% of predicted, 30.95±39.92 vs. 57.82±25.71, P=0.00) at diagnosis than the group that developed OLD with a favorable prognosis (n=23). The group that developed OLD with an unfavorable prognosis had significant reductions in FVC, FEV1, FEV1/FVC, and FEF25-75 at 2 years after diagnosis. Children who develop OLD with an unfavorable prognosis after HSCT already have poor lung function at the time of diagnosis. Additional treatment should be considered in patients who develop OLD after HSCT according to their PFTs at diagnosis.

Assessment of pulmonary outcomes, exercise capacity, and longitudinal changes in lung function in pediatric survivors of high-risk neuroblastoma

BACKGROUND/OBJECTIVES

Survivors of high-risk neuroblastoma (NB) are exposed to multimodality therapies early in life and confront late therapy-related toxicities. This study assessed respiratory symptoms, exercise capacity, and longitudinal changes in pulmonary function tests (PFTs) among survivors.

DESIGN/METHODS

Survivors of high-risk NB followed in the long-term follow-up clinic at Memorial Sloan Kettering Cancer Center were enrolled. Symptom and physical activity questionnaires were completed. Medical records were reviewed for treatments and comorbidities. Participants completed spirometry, plethysmography, diffusion capacity of the lung for carbon monoxide, 6-minute walk tests (6MWTs), and cardiopulmonary exercise testing. Questionnaires and PFTs were repeated at least one year after enrollment.

RESULTS

Sixty-two survivors participated (median age at study: 10.92 years; median age at diagnosis: 2.75 years; median time since completion of therapy: 5.29 years). Thirty-two percent had chronic respiratory symptoms. Seventy-seven percent had PFT abnormalities, mostly mild to moderate severity. Thirty-three completed 6MWTs (median, 634.3 meters); eight completed cardiopulmonary exercise tests (mean VO₂ max: 63% predicted); 23 completed a second PFT revealing declines over a median 2.97 years (mean percent predicted forced vital capacity: 79.9 to 70.0; mean forced expiratory volume in 1 second: 81.6 to 69.9). Risks for abnormalities included thoracic surgery, chest radiation therapy (RT), thoracic surgery plus chest RT, and hematopoietic stem cell transplant.

CONCLUSIONS

In this cohort of survivors of high-risk NB, PFT abnormalities were common but mostly mild or moderate. Maximal exercise capacity may be affected by respiratory limitations and declines in lung function may occur over time. Continued pulmonary surveillance of this at-risk population is warranted.

Monitoring lung function in patients with chronic graft versus host disease: a pilot study

Bronchiolitis obliterans syndrome (BOS) following allogenic haematopoietic stem cell transplant is considered the manifestation of chronic graft versus host disease (cGvHD) in the lung, and affects about 14% of patients with cGvHD, mainly in the first 2 years after transplant. Despite advances in assessment, diagnosis and treatment, the clinical prognosis remains poor for patients with pulmonary manifestations of cGvHD. A pilot study of 50 patients was devised to establish whether a relationship exists between forced expiratory volume in 1 second (FEV1) via pulmonary function test (PFT) and the equivalent peak expiratory flow (PEF) via peak flow handheld spirometry in cGvHD patients receiving extracorporeal photopheresis (ECP). Only PEF observed within 2 days of PFT could be compared with data at month 3, 6, 9 and 12. This pilot study illustrated that monitoring via handheld peak flow readings has the potential to become an acceptable method of monitoring lung function longitudinally in cGvHD patients.

Long-term Pulmonary Outcomes in Pediatric Survivors of High-risk Neuroblastoma

BACKGROUND

Children with high-risk neuroblastoma are exposed to multimodality therapies early in life and survivors confront late therapy-related toxicities. This study assessed respiratory symptoms, pulmonary function tests (PFTs), and risk factors for abnormalities among survivors.

MATERIALS AND METHODS

High-risk neuroblastoma survivors followed in the long-term follow-up clinic at Memorial Sloan Kettering Cancer Center were enrolled. Self-administered symptom questionnaires were completed. Medical records were reviewed for treatment information and comorbidities. PFTs included spirometry, plethysmography, and diffusion capacity of the lung for carbon monoxide (DLCO).

RESULTS

Thirty-nine survivors participated (median age at study: 11.4 y; median age at diagnosis: 2.3 y; median time since completion of therapy: 5.5 y). Chronic respiratory symptoms were reported for 33%. PFT abnormalities were identified in 79% and included low forced expiratory volume in 1 second (38%), decreased total lung capacity (44%), and abnormal DLCO (67%). PFT abnormalities were mostly mild to moderate. Mean forced vital capacity, forced expiratory volume in 1 second, and total lung capacity were normal and mean DLCO was mildly abnormal. Risks included thoracic surgery, chest radiation therapy, thoracic surgery plus chest radiation therapy, and shorter time since completion of therapy (P<0.05).

CONCLUSIONS

Although respiratory abnormalities were common, they were mostly mild or moderate. Continued pulmonary surveillance of this at-risk population is warranted.

Recovery of Pulmonary Function after Allogeneic Hematopoietic Cell Transplantation in Children is Associated with Improved Survival

Abnormal pulmonary function is prevalent in survivors of allogeneic hematopoietic cell transplantation (HCT). Post-transplantation recovery of pulmonary function, and its effect on survival, in children are not known. This retrospective cohort study of 308 children followed for 10 years after HCT at a single institution included 2 groups of patients. Group 1 comprised 188 patients with 3 or more pulmonary function test (PFT) results, of which at least 1 was abnormal, and group 2 comprised 120 patients with 3 or more PFTs, all of which were normal. Pulmonary function normalized post-transplantation in 51 patients (27%) in group 1. Obstructive lung disease, restrictive lung disease, mixed lung disease, and normal pattern were seen in 43%, 25%, 5%, and 27% of patients, respectively, at a median of 5 years (range, 0.5 to 11.9 years) post-transplantation. Lung volumes recovered better than spirometric indices. Pulmonary complications were seen in 80 patients (43%) in group 1. Patients who recovered pulmonary function had better overall survival (P = .006), which did not differ significantly from that in patients in group 2 with normal lung function post-transplantation (P = .80). After adjusting for duration of follow-up, pulmonary complications (P = .01), and lower pretransplantation forced vital capacity z-scores (P = .01) were associated with poor recovery. T cell depletion (P < .001), lower pretransplantation forced expired volume in 1 second z-scores (P = .006), and chronic graft-versus-host disease (P < .001) increased the risk for pulmonary complications. Nonrecovery of lung function with pulmonary complications (P = .03), acute graft-versus-host disease (P = .004), and mechanical ventilation (P < .001) were risk factors for nonrelapse mortality. Normalization of pulmonary function is possible in long-term survivors of allogeneic HCT. Strategies to decrease the risk of pulmonary complications may improve outcomes.

Pre-hematopoietic stem cell transplant lung function and pulmonary complications in children

RATIONALE

Pulmonary complications are a significant cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation.

OBJECTIVES

The relationship between pretransplant pulmonary function tests (PFTs) and development of post-transplant pulmonary complications in children was studied.

METHODS

This is a retrospective single institution cohort study of 410 patients who underwent pretransplant PFT and were monitored to 10 years posttransplant.

MEASUREMENTS AND MAIN RESULTS

Pulmonary complications were observed in 174 (42%) patients. Children with pulmonary complications had significantly lower forced expiratory flow at 25-75% of vital capacity (P = 0.02) derived using conventional predicted equations for age, and the Global Lung Initiative-2012 predicted equations (P = 0.01). T-cell depletion (P = 0.001), acute grade 3-4 graft-versus-host disease (P = 0.008), and chronic graft-versus-host disease (P = 0.01) increased risk for pulmonary complications. Patients who had pulmonary complications had a 2.8-fold increased risk of mortality (P < 0.0001). The cumulative incidence of death due to pulmonary complications was significantly higher in children who had low lung volumes, FRC less than 50% (P = 0.005), TLC less than 50% (P = 0.0002), residual volume less than 50% (P = 0.007), and T-cell depletion (P = 0.01). Lower FEV1 (P = 0.0005), FVC (P = 0.0005), TLC (P  <  0.0001), residual volume less than 50% (P = 0.01), and restrictive lung disease (P = 0.01) predicted worse overall survival.

CONCLUSIONS

Abnormal pretransplant PFT significantly increased risk after transplant. These patients may benefit from modified transplant strategies to reduce morbidity and mortality.

Effectiveness of long-term routine pulmonary function surveillance following pediatric hematopoietic stem cell transplantation

INTRODUCTION

Pulmonary complications following hematopoietic stem cell transplantation (HSCT) are common and often subclinical. Thus, periodic pulmonary function testing (PFT) is mandatory. This study sought to evaluate the effectiveness of long-term PFT surveillance for children undergoing HSCT and identify potential risk factors.

METHODS

We reviewed long-term PFT for HSCT patients at a tertiary pediatric center. Inclusion criteria were PFT prior to and at least once following HSCT.

RESULTS

Fifty-seven patients performed 202 spirometry and 193 plethysmographic maneuvers; 41 were tested during the first year after HSCT, but only 29 were evaluated consistently long term (2-12 years). FVC and FEV(1) decreased gradually suggesting a restrictive ventilatory defect: FVC % predicted [mean ± SD] dropped from 91 ± 14% to 85 ± 17% after 0-24 months and 80 ± 19% beyond 2 years (P = 0.01) whereas FEV(1) dropped from 95 ± 16% to 88 ± 19% and 82 ± 20%, respectively (P = 0.002). A slight reduction in TLC was observed. Those undergoing allogeneic HSCT had a greater decline in FVC (P = 0.025) and FEV(1) (P = 0.025) as did those conditioned with radiation, regarding both FVC (P = 0.003) and FEV(1) (P = 0.002). Decline occurred earlier (≤2 years) after chemotherapy compared with radiation. Seven children had severe irreversible obstruction at >2 years despite therapeutic intervention.

CONCLUSIONS

Most survivors of childhood HSCT maintain almost normal pulmonary function although mild restrictive lung disease may develop, particularly following allogeneic HSCT and conditioning with radiation. Severe airways obstruction developed in a small minority. The surveillance protocol for PFT needs to be followed more stringently to enable intervention possibly before early subclinical changes progress and become irreversible.

Lung function after allogeneic hematopoietic stem cell transplantation in children: a longitudinal study in a population-based cohort

Reduction in pulmonary function (PF) has been reported in up to 85% of pediatric patients during the first year after hematopoietic stem cell transplantation (HSCT). Our understanding of the etiology for this decrease in lung function is, however, sparse. The aim of this study was to describe PF during follow-up in a population-based pediatric HSCT cohort and to investigate factors in the transplantation process associated with PF decline. A retrospective, population-based, single-center study of HSCT patients spanning 2 decades was performed. Longitudinal changes in PF over time and associations to transplantation-related factors were investigated using a mixed linear model. One hundred thirty patients were included in the longitudinal analysis and observed for a median (range) of 3.3 (.2 to 16.8) years, during which 1084 PF tests were performed. Sixty-two percent of the patients experienced a decline in lung function of more than 10% during the first 3 to 9 months after HSCT. The decline in forced expiratory volume in 1 second, forced expiratory volume in 1 second/forced vital capacity and diffusion capacity of the lung for carbon monoxide were strongly associated with acute graft-versus-host disease (GvHD). Other factors associated with PF decline were malignant diagnosis, busulfan-based conditioning, patient and donor age, female donor to male recipient, as well as chronic GvHD. Mild to moderate decline in PF is frequent and appears associated with acute GvHD and other parameters that are risk factors for chronic GvHD in children. This indicates that alloreactivity is central in pathogenesis of the decrease in PF that follows HSCT in children.

[Examination of late pulmonary toxicity in children treated for malignancies]

INTRODUCTION

The present investigation was based on a survey in 2005, in which the authors found pulmonary function abnormalities in survivors of childhood cancer, who were treated with anticancer therapy.

AIM

The purpose of the present study was to follow-up childhood cancer survivors and detect late pulmonary toxicity.

PATIENTS AND METHODS

Lung function test was performed with spirometry in 26 survivors participated in this study (10 females and 16 males; mean age, 19.4 years at the time of the second follow-up evaluation). The average time periods from treatment until the first and second follow-up evaluation were 4.5 and 10 years, respectively.

RESULTS

The authors found 14 patients with pathological pulmonary function tests results at the time of the first follow-up evaluation, from which 7 patients had obstructive, 5 patients had mixed and 2 patients had restrictive abnormalities. However, there were only 6 patients who had abnormal pulmonary function at the time of the second follow-up evaluation (2 patients with obstructive and 4 patients with restrictive pulmonary function tests (p<0.05).

CONCLUSION

Restrictive pulmonary disorder was detected in only small part of the treated patients. The obstructive pulmonary abnormalities caused by the treatment showed an improving tendency over time.

Pulmonary outcomes in survivors of childhood cancer: a systematic review

BACKGROUND

The purpose of this article is to summarize the literature that documents the long-term impact of cancer treatment modalities on pulmonary function among survivors of cancer and to identify potential areas for further research.

METHODS

Systematic reviews of clinical trials, observational studies, case series, and review articles were conducted. Articles were limited to the studies that discussed pulmonary toxicity or late effects among pediatric cancer survivors and to follow-up investigations that were conducted a minimum of 2 years after completion of cancer-related treatment or 1 year after hematopoietic stem cell transplant.

RESULTS

Sixty publications (51 clinical studies/reports and nine reviews) published from January 1970 to June 2010 in PubMed met the inclusion criteria. Data showed an association between radiotherapy, alkylating agents, bleomycin, hematopoietic stem cell transplant, and thoracic surgery and pulmonary toxicity, as well as possible interactions among these modalities.

CONCLUSIONS

Pulmonary toxicity is a common long-term complication of exposure to certain anticancer therapies in childhood and can vary from subclinical to life threatening. Pulmonary function and associated loss of optimal exercise capacity may have adverse effects on long-term quality of life in survivors. Lung function diminishes as a function of normal aging, and the effects of early lung injury from cancer therapy may compound these changes. The information presented in this review is designed to provide a stimulus to promote both observational and interventional research that expands our knowledge and aids in the design of interventions to prevent or ameliorate pulmonary late effects among survivors of childhood cancer.

Diagnosis and treatment of pulmonary chronic GVHD: report from the consensus conference on clinical practice in chronic GVHD

This consensus statement established under the auspices of the German working group on BM and blood stem cell transplantation (DAG-KBT), the German Society of Hematology and Oncology (DGHO), the Austrian Stem Cell Transplant Working Group, the Swiss Blood Stem Cell Transplantation Group (SBST) and the German-Austrian Pediatric Working Group on SCT (Päd-Ag-KBT) summarizes current evidence for diagnosis, immunosuppressive and supportive therapy to provide practical guidelines for the care and treatment of patients with pulmonary manifestations of chronic GVHD (cGVHD). Pulmonary cGVHD can present with obstructive and/or restrictive changes. Disease severity ranges from subclinical pulmonary function test (PFT) impairment to respiratory insufficiency with bronchiolitis obliterans being the only pulmonary complication currently considered diagnostic of cGVHD. Early diagnosis may improve clinical outcome, and regular post-transplant follow-up PFTs are recommended. Diagnostic work-up includes high-resolution computed tomography, bronchoalveolar lavage and histology. Topical treatment is based on inhalative steroids plus beta-agonists. Early addition of azithromycin is suggested. Systemic first-line treatment consists of corticosteroids plus, if any, continuation of other immunosuppressive therapy. Second-line therapy and beyond includes extracorporeal photopheresis, mammalian target of rapamycin inhibitors, mycophenolate, etanercept, imatinib and TLI, but efficacy is limited. Clinical trials are urgently needed to improve understanding and treatment of this deleterious complication.

Lung function and late pulmonary complications among survivors of hematopoietic stem cell transplantation during childhood

Hematopoietic stem cell transplantation (HSCT) is used to treat an expanding array of malignant and non-malignant disorders. Pulmonary complications represent a significant source of morbidity and mortality in HSCT recipients. Young children, whose lungs are still developing and growing, may be especially susceptible to the insults of irradiation, drug toxicities, and recurrent infections associated with immunosuppression. Late pulmonary complications, those occurring more than three months after transplantation, are often noninfectious and present with nonspecific symptomatology. Pulmonary function testing (PFT) is a mainstay of monitoring pulmonary health in HSCT recipients. The pulmonologist should be familiar with common patterns seen on PFT in recipients of HSCT during childhood. In this review, we describe the findings in studies which have examined lung function over time in patients who underwent HSCT during childhood. We discuss patterns of PFT abnormalities, associated noninfectious syndromes and their clinical implications, as well as directions for future research.