Evaluation of practical experiences of German speaking radiation oncologists in combining radiation therapy with checkpoint blockade

Palliative Thoracic Radiotherapy in the Era of Modern Cancer Care for NSCLC

Palliative thoracic radiotherapy provides rapid and effective symptom relief in approximately two-thirds of NSCLC patients treated. In patients with poor performance status, the degree of palliation appears unrelated to the radiation dose or fractionation schedule. Conversely, in patients with good performance status, higher radiation doses administered over longer periods have shown modest survival benefits. These findings stem from studies conducted before the advent of immunotherapy and targeted therapy in clinical practice. Currently, there are no large prospective studies specifically dedicated to palliative radiotherapy conducted in this new treatment era. Modern radiotherapy technologies are now widely available and are increasingly used for palliative purposes in selected patients, reflecting the expanded array of therapeutic options for disseminated NSCLC and improved prognosis. Some traditional tenets of palliative thoracic radiotherapy, such as the improvement of overall survival with a protracted radiation schedule and the use of simple, cost-effective radiation techniques for palliative purposes, may no longer hold true for patients receiving immunotherapy or targeted therapy. The application of IMRT or SBRT in the context of palliative radiotherapy for NSCLC is not yet sufficiently explored, and this is addressed in this review. Moreover, new risks associated with combining palliative radiotherapy with these systemic treatments are being explored and are discussed within the context of palliative care. The optimal timing, doses, fractionation schedules, and treatment volumes for radiotherapy combined with immunotherapy or targeted therapy are currently subjects of investigation. In emergencies, radiotherapy should be used as a life-saving measure without delay. However, for other indications of palliative thoracic radiotherapy, decisions regarding doses, timing relative to systemic treatments, and treatment volumes should be made in a multidisciplinary context, considering the patient's prognosis, anticipated outcomes, and access to potentially effective treatments. We still lack robust data from prospective studies on this matter. This review examines and discusses available evidence on the use of palliative thoracic radiotherapy within the framework of modern treatment strategies for NSCLC.

Immune checkpoint inhibitor-related adverse events: Real-world experience from a single veterans' affairs medical center

BACKGROUND

Immune checkpoint inhibitors (ICIs) are antineoplastic agents associated with a multitude of immune-related adverse events (irAEs). Available data from clinical trials include highly selective patient populations which may limit their applicability to real-world clinical practice.

METHODS

We present a retrospective cohort study of cancer patients treated with ICI therapy at the Zablocki VA Medical Center between 2014 and 2021. Information on demographics, cancer diagnosis, type of therapy, treatment duration, comorbidities, irAE type, and overall survival were collected.

RESULTS

We identified 187 patients who received at least one dose of ICI. About half the patients experienced at least one irAE, the most common categories being fatigue, pulmonary, and endocrine irAEs. Approximately half of the irAEs were diagnosed within the first three months of starting ICI therapy, and 60.38% of those who experienced irAEs discontinued ICI therapy. Patients who experienced endocrine or intestinal irAEs had a significantly longer overall survival.

CONCLUSION

Immune-related complications due to ICI therapy are common and can frequently lead to treatment discontinuation in the real-world setting. Endocrine and intestinal irAEs may correlate with improved survival. The ICI-treated patients who received palliative radiation therapy to the bone had less irAEs, possibly due to immunogenic cell death.

Optimal management of radiation pneumonitis: Findings of an international Delphi consensus study

PURPOSE

Radiation pneumonitis (RP) is a dose-limiting toxicity for patients undergoing radiotherapy (RT) for lung cancer, however, the optimal practice for diagnosis, management, and follow-up for RP remains unclear. We thus sought to establish expert consensus recommendations through a Delphi Consensus study.

METHODS

In Round 1, open questions were distributed to 31 expert clinicians treating thoracic malignancies. In Round 2, participants rated agreement/disagreement with statements derived from Round 1 answers using a 5-point Likert scale. Consensus was defined as ≥ 75 % agreement. Statements that did not achieve consensus were modified and re-tested in Round 3.

RESULTS

Response rate was 74 % in Round 1 (n = 23/31; 17 oncologists, 6 pulmonologists); 82 % in Round 2 (n = 19/23; 15 oncologists, 4 pulmonologists); and 100 % in Round 3 (n = 19/19). Thirty-nine of 65 Round 2 statements achieved consensus; a further 10 of 26 statements achieved consensus in Round 3. In Round 2, there was agreement that risk stratification/mitigation includes patient factors; optimal treatment planning; the basis for diagnosis of RP; and that oncologists and pulmonologists should be involved in treatment. For uncomplicated radiation pneumonitis, an equivalent to 60 mg oral prednisone per day, with consideration of gastroprotection, is a typical initial regimen. However, in this study, no consensus was achieved for dosing recommendation. Initial steroid dose should be administered for a duration of 2 weeks, followed by a gradual, weekly taper (equivalent to 10 mg prednisone decrease per week). For severe pneumonitis, IV methylprednisolone is recommended for 3 days prior to initiating oral corticosteroids. Final consensus statements included that the treatment of RP should be multidisciplinary, the uncertainty of whether pneumonitis is drug versus radiation-induced, and the importance risk stratification, especially in the scenario of interstitial lung disease.

CONCLUSIONS

This Delphi study achieved consensus recommendations and provides practical guidance on diagnosis and management of RP.

Palliative extracranial radiotherapy in patients receiving immunotherapy for non-small cell lung cancer: a narrative review

Background and Objective

Role of radiotherapy (RT) in the era of immuno-oncology (IO) in advanced non-small cell lung cancer (NSCLC) is rapidly changing. RT is not only intended for addressing palliation symptoms but also is considered as a potential tool potentializing an immunogenic effect of given drugs. However, the best timing, techniques, doses, volumes, and its use for asymptomatic patients is a subject of research. We performed a review on the role of palliative RT schedules in combination with IO for advanced NSCLC. Indications in symptomatic and asymptomatic patients, outcomes, toxicity, and possible developments are discussed.

Methods

A literature search was conducted in MEDLINE and PubMed databases and clinicaltrials.gov using the keywords 'lung cancer' AND "immunotherapy" AND 'radiotherapy' OR "palliative radiotherapy".

Key Content and Findings

Body of evidence indicate that palliative RT used in combination with IO is effective in terms of symptom management and safe; does not increase the risk of serious side effects, including serious pulmonary toxicity. We have limited data evidencing improvement of survival by addition of short ablative RT dose to one site of the disease to IO in oligometastatic NSCLC. Some data indicate that short ablative doses of stereotactic body radiation therapy (SBRT) are more effective with regard to treatment response and survival than protracted RT schedule with lower fractional doses. However, this may be a selection bias of better prognostic patients who underwent SBRT. The use of steroids being a potential concern during IO should not be prohibited if clinically indicated during palliative RT. Its detrimental effect shown in some studies may also be a result of selection bias, because steroids given for not cancer-related causes during IO did not decrease survival.

Conclusions

RT for symptom management may be used during, directly before or after IO. This has a potential to ease symptom burdens and improve performance status (PS). However, still more studies are needed to establish optimal guidelines in asymptomatic patients for appropriate timing, volumes, dose, and fractionation schedules of palliative RT use in combination with IO.

Experimental investigation of skin toxicity after immune checkpoint inhibition in combination with radiation therapy

Immune checkpoint inhibitors (ICIs) have revolutionized cancer therapy. However, structured knowledge to mitigate a patient's specific risk of developing adverse events are limited. Nevertheless, there is an exponential growth of clinical studies combining conventional therapies such as radiation therapy (RT) with ICIs. Cutaneous reactions are amongst the most common adverse events after monotherapy with either ICIs or RT. So far, little is known about inter-individual differences in the risk of developing severe tissue toxicity after the combination of RT with ICIs, and the underlying biological mechanisms are ill defined. We used experimental models of RT-induced skin injury to analyze skin toxicity after simultaneous application of ICIs. We compared different RT regimens such as fractionated or stereotactic RT with varying dose intensity. Strikingly, we found that simultaneous application of RT and ICIs did not significantly aggravate acute skin injury in two different mouse strains. Detailed examination of long-term tissue damage of the skin revealed similar signs of epidermal hyperplasia, dermal fibrosis, and adnexal atrophy. In summary, we here present the first experimental study demonstrating excellent safety profiles of concurrent treatment with RT and ICIs. These findings will help to interpret the development of adverse events of the skin after radioimmunotherapy and guide the design of new clinical trials and clinical decision making in individual cases. This article is protected by copyright. All rights reserved.

Hypofractionated radiotherapy combined with targeted therapy or immunotherapy: Dutch survey on current practice, knowledge and challenges

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Radiotherapy referral during targeted therapy or immunotherapy occurs regularly.

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There is a knowledge gap regarding the implications of combined therapy.

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There is no consensus on expected toxicity of combined therapy.

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Multidisciplinary protocols regarding combined therapy are often not available.

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The application of radiotherapy treatment adaptations varies widely when combined with different systemic treatments.

Introduction

With the introduction of tyrosine kinase inhibitors and systemic antibodies, including immune checkpoint inhibitors, the survival of advanced-stage cancer patients has improved for many tumor types. These patients are increasingly referred for radiotherapy, but it is unclear whether radiotherapy combined with these drugs is safe. No international guidelines exist on whether or how to combine these drugs with radiotherapy. Therefore, we investigated the current clinical practice in the Netherlands regarding hypofractionated radiotherapy in patients using targeted drugs and immunotherapy.

Materials and methods

We sent a survey to all 21 Dutch radiotherapy institutes. Dedicated radiation oncologists, medical oncologists and pulmonologists were asked to fill out the survey. The questions explored their familiarity with the combination of targeted drugs and immunotherapy with radiotherapy, the encountered clinical difficulties and factors influencing treatment decisions.

Results

The survey was filled out by 54 respondents from 19 different institutes. The median annual number of patients per radiation oncologist referred for radiotherapy when using targeted drugs or immunotherapy was 10 and 15, respectively. Despite this high number, only 11% of the radiation oncologists stated that they had sufficient information (resources) for adequate treatment decision making. Among all physicians, 44% stated that there was insufficient knowledge within their institute regarding this topic. Only 17% stated that there was a multidisciplinary protocol available. The application of radiotherapy treatment adaptations (technique, dose, fractionation, field size) varied widely. Generally, there seemed to be no consensus regarding the expected toxicity of combined drug-radiotherapy treatments and the expected risk of tumor flare upon temporary drug discontinuation.

Conclusion

There is no consensus amongst involved medical specialties on expected toxicity. Consequently, it is necessary to perform clinical studies examining the safety of combined drug-radiotherapy treatments, to add radiotherapy to phase I-III clinical trials for new drugs and to incorporate outcomes into multidisciplinary, evidence-based guidelines.