Clinical relevance of radiation pneumonitis in breast cancers

Impact of adjuvant radiotherapy on patient-reported shortness of breath in patients with breast cancer using the ESAS

BACKGROUND AND PURPOSE

As breast cancer radiotherapy (RT) has been shown to give rise to adverse pulmonary outcomes, such as radiation pneumonitis, trends in patient-reported shortness of breath (SOB) associated with RT were investigated. Adjuvant RT is commonly administered for local and/or regional control of breast cancer and was therefore included.

METHODS

The Edmonton Symptom Assessment System (ESAS) was used to observe changes in SOB during RT, up to 6 weeks after RT completion, and one to three months post-RT. Patients with at least one completed ESAS were included in the analysis. Generalized linear regression analysis was performed to identify associations between demographic factors and SOB.

RESULTS

A total of 781 patients were included in the analysis. There was a significant association between ESAS SOB scores and adjuvant chemotherapy when compared to neoadjuvant chemotherapy (p=0.0012). Meanwhile, loco-regional RT had no significant impact on ESAS SOB scores in comparison to local RT. SOB scores were stable over time (p>0.05) from baseline to follow-up appointments.

CONCLUSION

The findings of this study suggest that RT was not associated with changes in SOB from baseline to 3 months post-RT. However, patients who underwent adjuvant chemotherapy reported significant higher SOB scores over time. Additional research is recommended to analyze the lasting effects of adjuvant breast cancer RT on SOB during physical activity.

Conventional versus hypofractionated postmastectomy radiotherapy: a report on long-term outcomes and late toxicity

Objective

We evaluated the long-term outcomes and late toxicity of conventional fractionated (CF) and hypofractionated (HF) postmastectomy radiotherapy (PMRT) in terms of locoregional recurrence-free survival (LRRFS), disease-free survival (DFS), overall survival (OS), and late toxicity.

Methods

A cohort of 1640 of breast cancer patients receiving PMRT between January 2004 and December 2014 were enrolled. Nine hundred eighty patients were treated with HF-PMRT: 2.65 Gy/fraction to a total of 42.4–53 Gy and 660 patients were treated with CF-PMRT: 2 Gy/fraction to a total of 50–60 Gy.

Results

The median follow-up time was 71.8 months (range 41.5–115.9 months). No significant difference was found in the rates of 5-year LRRFS, DFS, and OS of HF-PMRT vs CF-PMRT; 96% vs. 94% (p = 0.373), 70% vs. 72% (p = 0.849), and 73% vs. 74% (p = 0.463), respectively. We identified a cohort of 937 eligible breast cancer patients who could receive late toxicities assessment. With a median follow-up time of this patient cohort of 106.3 months (range 76–134 months), there was a significant higher incidence of grade 2 or more late skin (4% vs 1%) and subcutaneous (7% vs 2%) toxicity in patients treated with HF-PMRT vs CF-PMRT. Patients who received additional radiation boost were significantly higher in the HF-PMRT group. Grade 2 or more late RTOG/EORTC lung toxicity was significant lesser in HF-PMRT vs CF-PMRT (9% vs 16%). Grade 1 brachial plexopathy was also significant lesser in HF-PMRT vs CF-PMRT (2% vs 8%). Heart toxicity and lymphedema were similar in both groups.

Conclusions

HF-PMRT is feasible to deliver with comparable long-term efficacy to CF-PMRT. HF-PMRT had higher grade 2 or more skin and subcutaneous toxicity but less lung and brachial plexus toxicity.

Dosimetric evaluation and systematic review of radiation therapy techniques for early stage node-negative breast cancer treatment

Radiation therapy (RT) is essential in treating women with early stage breast cancer. Early stage node-negative breast cancer (ESNNBC) offers a good prognosis; hence, late effects of breast RT becomes increasingly important. Recent literature suggests a potential for an increase in cardiac and pulmonary events after RT. However, these studies have not taken into account the impact of newer and current RT techniques that are now available. Hence, this review aimed to evaluate the clinical evidence for each technique and determine the optimal radiation technique for ESNNBC treatment. Currently, six RT techniques are consistently used and studied: 1) prone positioning, 2) proton beam RT, 3) intensity-modulated RT, 4) breath-hold, 5) partial breast irradiation, and 6) intraoperative RT. These techniques show dosimetric promise. However, limited data on late cardiac and pulmonary events exist due to challenges in long-term follow-up. Moving forward, future studies are needed to validate the efficacy and clinical outcomes of these current techniques.

18F-FDG PET/CT in Patients with Parenchymal Changes Attributed to Radiation Pneumonitis

Objectives:

Radiation pneumonitis (RP) can be an adverse complication of radiotherapy (RT) and can limit the application of the already planned radiation dose. It is often associated with RT of lung carcinoma and is occasionally caused by radiation therapy of breast carcinoma and lymphomas located in the mediastinum. Positron emission tomography/computed tomography (PET/CT) emerges lately as a prospective modality for early diagnostics of RP. The aim of this study was to summarize the initial data from diagnostic application of PET/CT in patients suspicious of RP and to derive criteria, which can help differentiate RP from early recurrence of the disease and/or residual tumor.

Methods:

The current study included 23 patients who had metabolic (PET) and anatomical (CT) changes consistent with RP. We additionally defined metabolic activity (SUV_max) in the lung parenchyma of 20 patients without RT.

Results:

All patients had increased metabolic activity in the lung parenchyma involved in the irradiated area with a mean SUV_max 3.45 (ranging between 1 and 7.1). The control group had a physiological background metabolic activity-SUV_max 0.61 +/- 0.11.

Conclusion:

Metabolic changes in patients suspicious of RP involved diffusely increased metabolic activity coinciding with the anatomical changes in the irradiated area. Three out of 23 patients had a proven recurrence of the primary neoplastic process in the irradiated area. The metabolic changes in those patients involved an increase in metabolic activity at follow-up or lack of tendency towards normalization after chemotherapy, which implied the existence of viable tumor cells. Our initial experience in the diagnostic application of ¹⁸F-FDG PET/CT in patients suspicious of RP allows us to summarize the following: PET/CT is a reliable imaging modality in the diagnostics of RP. Through its sequential use, we can differentiate inflammatory changes related to RP from early recurrence of the primary neoplastic process.