Changes in pulmonary function and influencing factors after high-dose intrathoracic radio(chemo)therapy

Understanding changes in pulmonary function and functional status in breast cancer patients after systemic chemotherapy and radiotherapy: a prospective study

BACKGROUND

Respiratory complications in breast cancer (BC) patients after chemotherapy (CT) and radiotherapy (RT) have been well acquainted and these complications should be investigated to prevent secondary problems and/or improve BC patients' clinical outcomes. Therefore, this study aimed to assess the potential acute effect of systemic chemotherapy and radiotherapy on respiratory function and functional status of patients with breast cancer.

METHODS

A total of 25 BC patients who were candidates for systemic chemotherapy and radiotherapy were recruited after oncological examination and included in this study. Respiratory function and functional status were assessed with the Pulmonary Function Test (PFT) and the Six-Minute Walk Test (6MWT), respectively. Patients were assessed before CT (c0), after CT (c1), and after RT (r1).

RESULTS

25 BC patients were assessed in c0 and c1 while only 15 out of 25 patients (60%) were assessed in r1. The actual values of Forced vital capacity (FVC) (t = 2.338, p =.028), Forced expiratory volume in 1s (FEV1 (t = 2.708, p =.012), and the forced expiratory flow of between 25% and 75% of vital capacity (FEF25-75%) (t = 2.200, p =.038) were found significantly different after systemic CT. Inspiratory (MIP) and expiratory (MEP) muscle strength also did not show a significant change from c0 to c1. A significant effect of the type of surgery was found (Wilks' lambda, F [1, 19] = 6.561, p =.019, ηp2 = 0.25) between c0 and c1 in actual FVC value. The main effect of time was found significant in FVC (F [2, 28] = 4.840, p =.016, ηp2 = 0.25) from c0 to r1. Pairwise comparisons with Bonferroni correction showed that there was a significant difference between c0 and r1 (p =.037).

DISCUSSION

The present study showed decreased FVC and FEV1 actual values and percent predicted rates from baseline to the completion of treatment. Since the interactional effect of the type of surgery was significant, we suggest that clinical and demographic factors such as age should be considered when interpreting the early changes in PFT. In addition, the significant linear trend of decreasing in some specific outcomes in respiratory function also highlighted the need for continuous monitoring of potential respiratory problems in patients with BC from baseline to the completion of chemotherapy and radiotherapy.

The evaluation of DLCO changes in patients with relatively higher lung shunt fractions receiving TARE

OBJECTIVE

Transarterial radioembolization (TARE) with Yttrium-90 (⁹⁰Y) labeled microspheres is an effective locoregional treatment option for patients with primary and metastatic liver cancer. However, TARE is also associated with radiation-induced lung injury due to hepatopulmonary shunting. If a large proportion of the injected radionuclide microspheres (more than 15%) is shunted, a rare but lethal complication may develop: radiation-induced pneumonitis (RP). Diffusion capacity of the lungs for carbon monoxide (DLCO) is a valuable test to assess lung function and a decrease in DLCO may indicate an impairment in gas exchange caused by the lung injury. Some previous researches have been reported the most consistent changes in pulmonary function tests after external beam radiotherapy are recorded with DLCO. This study aimed to examine the changes in DLCO after TARE with glass microspheres in newly treated and retreated patients with relatively higher lung shunt fractions.

METHODS

We prospectively analyzed forty consecutive patients with liver malignancies who underwent lobar or superselective TARE with ⁹⁰Y glass microspheres. DLCO tests were performed at baseline and on days 15, 30, and 60 after the treatment. All patients were followed up clinically and radiologically for the development of RP.

RESULTS

A statistically significant decrease was found in the DLCO after the first treatment (81.4 ± 13.66 vs. 75.25 ± 13.22, p = 0.003). The frequency of the patients with impaired DLCO at baseline was significantly increased after the first treatment (37.5 vs 57.5% p < 0.05). In the retreated group (n = 8), neither the DLCO (71.5 ± 10.82 vs. 67.50 ± 11.24, p = 0.115) nor the frequency of patients with impaired DLCO (25 vs 25%, p = 1) did not significantly change. Also, the change in DLCO values did not significantly correlate with lung shunt fraction, administered radiation dose, and absorbed lung dose after the first and second treatments (p > 0.05 for all). None of the patients developed RP.

CONCLUSION

Our study showed that a significant reduction in DLCO after TARE may occur in patients with relatively higher lung shunt fractions. Further studies with larger sample sizes are needed to better investigate the changes in DLCO in patients with high lung shunt fractions.

Impact of Low-Dose Irradiation of the Lung and Heart on Toxicity and Pulmonary Function Parameters after Thoracic Radiotherapy

Simple Summary

To assess the impact of thoracic (low) dose irradiation on pulmonary function changes after thoracic radiotherapy (RT) data of 62 patients were analyzed. There were several significant correlations between pulmonary function and dose parameters of the lung and heart, most of which remained significant in the multivariate analysis.

Abstract

Objective: To assess the impact of (low) dose irradiation to the lungs and heart on the incidence of pneumonitis and pulmonary function changes after thoracic radiotherapy (RT). Methods/Material: Data of 62 patients treated with curative thoracic radiotherapy were analyzed. Toxicity data and pulmonary function tests (PFTs) were obtained before RT and at 6 weeks, at 12 weeks, and at 6 months after RT. PFTs included ventilation (e.g., vital capacity) and diffusion parameters (e.g., diffusion capacity for carbon monoxide (DL_CO)). Dosimetric data of the lung and heart were extracted to assess the impact of dose on PFT changes and radiation pneumonitis (RP). Results: No statistically significant correlations between dose parameters and changes in ventilation parameters were found. There were statistically significant correlations between DL_CO and low-dose parameters of the lungs (V_5Gy–V_30Gy (%)) and irradiation of the heart during the follow-up up to 6 months after RT, as well as a temporary correlation of the V_60Gy (%) on the blood gas parameters at 12 weeks after RT. On multivariate analysis, both heart and lung parameters had a significant impact on DL_CO. There was no statistically significant influence of any patient or treatment-related (including dose parameters) factors on the incidence of ≥G2 pneumonitis. Conclusion: There seems to be a lasting impact of low dose irradiation to the lung as well as irradiation to the heart on the DL_CO after thoracic radiotherapy. No influence on RP was found in this analysis.

Radiation-induced lung toxicity - cellular and molecular mechanisms of pathogenesis, management, and literature review

Lung, breast, and esophageal cancer represent three common malignancies with high incidence and mortality worldwide. The management of these tumors critically relies on radiotherapy as a major part of multi-modality care, and treatment-related toxicities, such as radiation-induced pneumonitis and/or lung fibrosis, are important dose limiting factors with direct impact on patient outcomes and quality of life. In this review, we summarize the current understanding of radiation-induced pneumonitis and pulmonary fibrosis, present predictive factors as well as recent diagnostic and therapeutic advances. Novel candidates for molecularly targeted approaches to prevent and/or treat radiation-induced pneumonitis and pulmonary fibrosis are discussed.

Effects of neoadjuvant chemotherapy on respiratory function in patients with breast cancer

Objective

To evaluate changes in chest X-rays, pulmonary function tests (PFTs) and quality of life in female breast cancer patients who had been treated with four cycles of neoadjuvant chemotherapy consisting of a regimen of cyclophosphamide, epirubicin and 5-fluorouracil (CEF regimen), and to determine the correlation between pulmonary function parameters and declined quality of life.

Methods

Twenty-nine eligible female patients diagnosed with breast cancer at the first visit who were 20−60 years old, were classified as the American Society of Anesthesiologists (ASA) I−II and patients whose body mass index (BMI) <30 kg/m² were recruited and subjected to chest X-ray examinations, PFTs and the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30 (EORTC QLQ-C30) questionnaire before and after receiving 4 cycles of the CEF regimen.

Results

In this study, chest X-rays showed no abnormal changes after chemotherapy, but significant decreases in carbon monoxide diffusing capacity (DLCO) and percentage of the DLCO predicted value (DLCO%) (P<0.001). A significant increase in maximal ventilatory volume (MVV) (P=0.004) was observed, and most patients experienced dyspnea (P=0.031) and fatigue (P<0.001). However, there was no significant correlation between the changes in these PFTs parameters and the results of the EORTC QLQ-C30 (P>0.05).

Conclusions

Neoadjuvant chemotherapy can reduce lung diffusion function and quality of life in females with breast cancer.

Acute severe radiation pneumonitis among non-small cell lung cancer (NSCLC) patients with moderate pulmonary dysfunction receiving definitive concurrent chemoradiotherapy: Impact of pre-treatment pulmonary function parameters

PURPOSE

Severe acute radiation pneumonitis (SARP) is a life-threatening complication of thoracic radiotherapy. Pre-treatment pulmonary function (PF) may influence its incidence. We have previously reported on the incidence of SARP among patients with moderate pulmonary dysfunction who received definitive concurrent chemoradiotherapy (dCCRT) for non-small cell lung cancer (NSCLC).

METHODS

The clinical outcomes, dose-volume histograms (DVH), and PF parameters of 122 patients (forced expiratory volume in 1 s [FEV1%]: 60-69%) receiving dCCRT between 2013 and 2019 were recorded. SARP was defined as grade ≥3 RP occurring during or within 3 months after CCRT. Logistic regression, receiver operating characteristics curves (ROC), and hazard ratio (HR) analyses were performed to evaluate the predictive value of each factor for SARP.

RESULTS

Univariate and multivariate analysis indicated that the ratio of carbon monoxide diffusing capacity (DLCO%; odds ratio [OR]: 0.934, 95% confidence interval [CI] 0.896-0.974, p = 0.001) and mean lung dose (MLD; OR: 1.002, 95% CI 1.001-1.003, p = 0.002) were independent predictors of SARP. The ROC AUC of combined DLCO%/MLD was 0.775 (95% confidence interval [CI]: 0.688-0.861, p = 0.001), with a sensitivity and specificity of 0.871 and 0.637, respectively; this was superior to DLCO% (0.656) or MLD (0.667) alone. Compared to the MLD-low/DLCO%-high group, the MLD-high/DLCO%-low group had the highest risk for SARP, with an HR of 9.346 (95% CI: 2.133-40.941, p = 0.003).

CONCLUSION

The DLCO% and MLD may predict the risk for SARP among patients with pre-treatment moderate pulmonary dysfunction who receive dCCRT for NSCLC. Prospective studies are needed to validate our findings.

Pulmonary function changes following helical tomotherapy in patients with inoperable, locally advanced non-small cell lung cancer

PURPOSE

To evaluate alterations in pulmonary function indices after helical tomotherapy and explore potential associations with biologically corrected dosimetric parameters.

PATIENTS AND METHODS

In 64 patients with inoperable locally advanced non-small cell lung cancer, pulmonary function tests before and within 6 months after radiotherapy were evaluated retrospectively. In the case of concurrent chemotherapy a total dose of 67.2 Gy was delivered, otherwise 70.5 Gy was provided. In 44 patients, late pulmonary function changes (≥6 months after radiotherapy) could also be assessed.

RESULTS

In the entire patient group, there were significant declines in forced expiratory volume in 1s (FEV₁) (average change -4.1% predicted; P = 0.007), in forced vital capacity (FVC) (-4.9% predicted; P = 0.002), total lung capacity (TLC) (-5.8% predicted; P = 0.0016) and DL_CO (diffusing capacity of the lung for carbon monoxide corrected for hemoglobin level) (-8.6% predicted; P < 0.001) during the first 6 months. Corresponding FEV₁, FVC, TLC and DL_CO declines in the subgroup with late measurements (after 11.3 months on average) were -5.7, -7.4, -7.0, -9.8% predicted. A multivariate analysis including V_5 Gy, V_10 Gy, V_20 Gy, V_40 Gy, V_60 Gy, mean lung dose (MLD), gross tumor volume (GTV) and planning target volume (PTV) as potential covariates showed that GTV was the most consistent contributor, being significant for ∆FEV₁ (P = 0.003), ∆FVC (P = 0.003), ∆TLC (P = 0.001) and ∆DL_CO (P = 0.01). V_5 Gy or V_10 Gy did not contribute to any of the lung function changes.

CONCLUSIONS

The decline in pulmonary function indices after helical tomotherapy was of similar magnitude to that observed in studies reporting the effect of conformal radiotherapy on lung function. Diffusion capacity was the parameter showing the largest decrease following radiation therapy as compared to baseline and correlated with gross tumor volume. None of the alterations in pulmonary function tests were associated with the lung volume receiving low-dose radiation.

Changes of lung parenchyma density following high dose radiation therapy for thoracic carcinomas - an automated analysis of follow up CT scans

Background

An objective way to qualify the effect of radiotherapy (RT) on lung tissue is the analysis of CT scans after RT. In this analysis we focused on the changes in Hounsfield units (ΔHU) and the correlation with the corresponding radiation dose after RT.

Methods

Pre- and post-RT CT scans were matched and ΔHU was calculated using customized research software. ΔHU was calculated in 5-Gy-intervals and the correlation between ΔHU and the corresponding dose was calculated as well as the regression coefficients. Additionally the mean ΔHU and ΔHU in 5-Gy-intervals were calculated for each tumor entity.

Results

The mean density changes at 12 weeks and 6 months post RT were 28,16 HU and 32,83 HU. The correlation coefficient between radiation dose and ΔHU at 12 weeks and 6 months were 0,166 (p = 0,000) and 0,158 (p = 0,000). The resulting regression coefficient were 1439 HU/Gy (p = 0,000) and 1612 HU/Gy (p = 0,000). The individual regression coefficients for each patient range from − 2,23 HU/Gy to 7,46 HU/Gy at 12 weeks and − 0,45 HU/Gy to 10,51 HU/Gy at 6 months. When looking at the three tumor entities individually the highest ΔHU at 12 weeks was seen in patients with SCLC (38,13 HU) and at 6 month in those with esophageal carcinomas (40,98 HU).

Conclusion

For most dose intervals there was an increase of ΔHU with an increased radiation dose. This is reflected by a statistically significant, although low correlation coefficient. The regression coefficients of all patients show large interindividual differences.

Temporal and spatial dose distribution of radiation pneumonitis after concurrent radiochemotherapy in stage III non-small cell cancer patients

Background and purpose

Radiation pneumonitis (RP) is the most common subacute side effect after concurrent chemoradiotherapy (CRT) for locally advanced non-small cell lung cancer. Several clinical and dose-volume (DV) parameters are associated with a distinct risk of symptomatic RP. The aim of this study was to assess the spatial dose distribution of the RP volume from first occurence to maximum volume expansion of RP.

Material and methods

Between 2007 and 2015, 732 patients with lung cancer were treated in an institution. Thirty-three patients met the following inclusion criteria: an RP grade II after CRT and a radiation dose ≥60 Gy and no prior medical history of cardiopulmonary comorbidities. The images of the first chest computed tomography (CT) confirming the diagnosis of RP and the CT images showing the maximum expansion of RP were merged with the treatment plan. The RP volume was delineated within the treatment plan, and a DV analysis was performed to evaluate the lung dose volume areas in which the RP manifested over time and whether dose volume changes within the RP volume occurred.

Results

A change from clinical diagnosis to maximum expansion of RP was observed as the RP at clinical appearance mainly manifested in the lower dose areas of the lung, whereas the RP volume at maximum expansion manifested in the higher dose areas, resulting in a significant shift of the assessed relative mean dose volume proportions within the RP volume. The mean relative dose volume proportion 0- ≤ 20 Gy decreased from 30.2% (range, 0–100) to 21.9% (range, 0–100; p = 0.04) at the expense of the dose volume > 40 Gy which increased from 39.2% (range, 0–100) to 49.8% (range, 0–100; p = 0.02), whereas the dose relative volume proportion > 20- ≤ 40 Gy showed no relevant change and slightly decreased from 30.6% (range, 0–85.7) to 28.3%, (range, 0–85.7; p = 0.34).

Conclusion

We observed a considerable increase in the relative dose proportions within the RP volume from diagnosis to maximum volume extent from low dose zones below 20 Gy to zones above 40 Gy. Although the clinical impact on RP remains unknown, a reduction of healthy healthy lung tissue receiving >40 Gy (V40) might be an additional parameter for irradiation planning in lung cancer patients.

Outcome and prognostic factors in single brain metastases from small-cell lung cancer

PURPOSE

Whole brain radiation therapy (WBRT) is historically the standard of care for patients with brain metastases (BM) from small-cell lung cancer (SCLC), although locally ablative treatments are the standard of care for patients with 1-4 BM from other solid tumors. The objective of this analysis was to find prognostic factors influencing overall survival (OS) and intracranial progression-free survival (iPFS) in SCLC patients with single BM (SBM) treated with WBRT.

METHODS

A total of 52 patients were identified in the authors' cancer center database with histologically confirmed SCLC and contrast-enhanced magnet resonance imaging (MRI) or computed tomography (CT), which confirmed SBM between 2006 and 2015 and were therefore treated with WBRT. A Kaplan-Meier survival analysis was performed for OS analyses. The log-rank (Mantel-Cox) test was used to compare survival curves. Univariate Cox proportional-hazards ratios (HRs) were used to assess the influence of cofactors on OS and iPFS.

RESULTS

The median OS after WBRT was 5 months and the median iPFS after WBRT 16 months. Patients that received surgery prior to WBRT had a significantly longer median OS of 19 months compared to 5 months in the group receiving only WBRT (p = 0.03; HR 2.24; 95% confidence interval [CI] 1.06-4.73). Patients with synchronous disease had a significantly longer OS compared to patients with metachronous BM (6 months vs. 3 months, p = 0.005; HR 0.27; 95% CI 0.11-0.68). Univariate analysis for OS revealed a statistically significant effect for metachronous disease (HR 2.25; 95% CI 1.14-4.46; p = 0.019), initial response to first-line chemotherapy (HR 0.58; 95% CI 0.35-0.97; p = 0.04), and surgical resection (HR 0.36; 95% CI 0.15-0.88; p = 0.026). OS was significantly affected by metachronous disease in multivariate analysis (HR 2.20; 95% CI 1.09-4.45; p = 0.028).

CONCLUSIONS

Univariate analysis revealed that surgery followed by WBRT can improve OS in patients with SBM in SCLC. Furthermore, synchronous disease and response to initial chemotherapy appeared to be major prognostic factors. Multivariate analysis revealed metachronous disease as a significantly negative prognostic factor on OS. The value of WBRT, stereotactic radiosurgery (SRS), or surgery alone or in combination for patients with a limited number of BM in SCLC should be evaluated in further prospective clinical trials.