Clinical characteristics and management of immune checkpoint inhibitor-related pneumonitis: A single-institution retrospective study

Clinical Manifestation, Risk Factors, and Immune Checkpoint Inhibitor Rechallenge of Checkpoint Inhibitor-Associated Pneumonitis in Patients With Lung Cancer

SUMMARY

Immune-related adverse effects can lead to damage to various systems of the body, checkpoint inhibitor-associated pneumonitis (CIP) is one of the potentially lethal immune-related adverse effects. However, evidence regarding the risk factors associated with CIP is limited. To timely and accurate identification and prompt treatment of CIP, understanding the risk factors for multimorbidity among diverse study populations becomes crucial. We retrospectively analyzed the clinical data of 1131 patients with lung cancer receiving immunotherapy to identify 110 patients with CIP, the clinical characteristics and radiographic features of patients with CIP were analyzed. A case-control study was subsequently performed to identify the risk factors of CIP. The median treatment cycle was 5 cycles and the median time to onset of CIP was 4.2 months. CIP was mainly grade I or II. Most cases improved after discontinuation of immune checkpoint inhibitors (ICIs) or hormone therapy. Severe CIP tended to occur earlier in comparison to mild to moderate cases. The recurrence rate was 20.6% in ICI-rechallenged patients, and patients with relapsed CIP were usually accompanied by higher-grade adverse events than at first onset. Among the 7 patients with relapse, ICI-associated deaths occurred in 2 patients (28.6%). For rechallenging with ICIs after recovery from CIP, caution should be practiced. Male [odds ratio (OR): 2.067; 95% CI: 1.194-3.579; P= 0.009], history of chest radiation (OR: 1.642; 95% CI: 1.002-2.689; P= 0.049) and underlying lung disease (OR: 2.347; 95% CI: 1.008-5.464; P=0.048) was associated with a higher risk of CIP.

Anti‑PD‑1/PD‑L1 and anti‑CTLA‑4 associated checkpoint inhibitor pneumonitis in non‑small cell lung cancer: Occurrence, pathogenesis and risk factors (Review)

Immune checkpoint inhibitors (ICIs) play a significant anti‑tumor role in the management of non‑small cell lung cancer. The most broadly used ICIs are anti‑programmed death 1 (PD‑1), anti‑programmed cell death‑ligand 1, and anti‑cytotoxic T lymphocyte‑associated antigen‑4 monoclonal antibody. Compared with traditional chemotherapy, ICIs have the advantages of greater efficiency and more specific targeting. However, the resulting immune‑related adverse events limit the clinical application of ICIs, especially checkpoint inhibitor pneumonitis (CIP). CIP chiefly occurs within 6 months of administration of ICIs. Excessive activation and amplification of cytotoxic T lymphocytes, helper T cells, downregulation of regulatory T cells, and over‑secretion of pro‑inflammatory cytokines are the dominant mechanisms underlying the pathophysiology of CIP. The dysregulation of innate immune cells, such as an increase in inflammatory monocytes, dendritic cells, neutrophils and M1 polarization of macrophages, an increase in IL‑10 and IL‑35, and a decrease in eosinophils, may underlie CIP. Although contested, several factors may accelerate CIP, such as a history of previous respiratory disease, radiotherapy, chemotherapy, administration of epidermal growth factor receptor tyrosine kinase inhibitors, PD‑1 blockers, first‑line application of ICIs, and combined immunotherapy. Interestingly, first‑line ICIs plus chemotherapy may reduce CIP. Steroid hormones remain the primary treatment strategy against grade ≥2 CIP, although cytokine blockers are promising therapeutic agents. Herein, the current research on CIP occurrence, clinical and radiological characteristics, pathogenesis, risk factors, and management is summarized to further expand our understanding, clarify the prognosis, and guide treatment.

Clinical characteristics and therapeutic effects of checkpoint inhibitor-related pneumonitis in patients with non-small cell lung cancer

BACKGROUND

With the application of immune checkpoint inhibitors (ICIs) in cancer treatment, more and more attention has been paid to checkpoint inhibitor-related pneumonitis (CIP), which requires a better understanding of its clinical characteristics and therapeutic effects.

METHODS

The clinical and imaging data of 704 patients with non-small cell lung cancer (NSCLC) who received immunotherapy were analyzed retrospectively; the clinical characteristics of CIP were summarized, and the therapeutic regimens and effects of the patients were summarized.

RESULTS

36 CIP patients were included in the research. The most common clinical symptoms were cough, shortness of breath and fever. The CT manifestations were summarized as follows: Organizing pneumonia (OP) in 14 cases (38.9%), nonspecific interstitial pneumonia (NSIP) in 14 cases (38.9%), hypersensitiviy pneumonitis(HP) in 2 cases (6.3%), diffuse alveolar damage in 1 case (3.1%) and atypical imaging manifestations in 5 cases (13.9%). 35 cases received glucocorticoid therapy, 6 patients were treated with gamma globulin and 1 patient was treated with tocilizumab. There were no deaths in CIP G1-2 patients and 7 deaths occured in CIP G3-4 patients. 4 patients were treated again with ICIs.

CONCLUSION

We found that glucocorticoid 1-2 mg/kg was effective for most patients with moderate to severe CIP, and a few patients with hormone insensitivity needed early immunosuppressive therapy. A few patients can be rechallenged with ICIs, but CIP recurrence needs to be closely monitored.

Association of Clinical and Radiological Features with Disease Severity of Symptomatic Immune Checkpoint Inhibitor-Related Pneumonitis

OBJECTIVES

To investigate the predictive ability of clinical and chest computed tomography (CT) features to predict the severity of symptomatic immune checkpoint inhibitor-related pneumonitis (CIP).

METHODS

This study included 34 patients diagnosed with symptomatic CIP (grades 2-5) and divided into mild (grade 2) and severe CIP (grades 3-5) groups. The groups' clinical and chest CT features were analyzed. Three manual scores (extent, image finding, and clinical symptom scores) were conducted to evaluate the diagnostic performance alone and in combination.

RESULTS

There were 20 cases of mild CIP and 14 cases of severe CIP. More severe CIP occurred within 3 months than after 3 months (11 vs. 3 cases, p = 0.038). Severe CIP was significantly associated with fever (p < 0.001) and the acute interstitial pneumonia/acute respiratory distress syndrome pattern (p = 0.001). The diagnostic performance of chest CT scores (extent score and image finding score) was better than that of clinical symptom score. The combination of the three scores demonstrated the best diagnostic value, with an area under the receiver operating characteristic curve of 0.948.

CONCLUSIONS

The clinical and chest CT features have important application value in assessing the disease severity of symptomatic CIP. We recommend the routine use of chest CT in a comprehensive clinical evaluation.

Risk Factors for Refractory Immune Checkpoint Inhibitor-related Pneumonitis in Patients With Lung Cancer

Checkpoint inhibitor-related pneumonitis (CIP) is one of the most important immune checkpoint inhibitors side effects, and it is rare but fatal. Identifying patients at risk of refractory CIP before the start of CIP therapy is important for controlling CIP. We retrospectively analyzed the clinical data of 60 patients with lung cancer who developed CIP. Refractory CIP was defined as CIP with poor response to corticosteroid treatment, including CIP not relieved with corticosteroid administration or CIP recurrence during the corticosteroid tapering period. We analyzed clinical characteristics, peripheral blood biomarkers, treatment, and outcomes in nonrefractory and refractory CIP. Risk factors associated with refractory CIP were assessed. Among 60 patients with CIP, 16 (26.7%) had refractory CIP. The median onset time for patients with nonrefractory and those with refractory CIP was 16.57 (interquartile range [IQR], 6.82-28.14) weeks and 7.43 (IQR, 2.71-19.1) weeks, respectively. The level of lactate dehydrogenase (LDH) was significantly higher in the refractory CIP group at baseline (255 [222, 418] vs. 216 [183, 252], P =0.031) and at CIP onset (321.5 [216.75, 487.5] vs. 219 [198. 241], P =0.019). An LDH level >320 U/L at CIP onset was an independent risk factor of refractory CIP (odds ratio [OR], 8.889; 95% confidence interval [CI]: 1.294-61.058; P =0.026). The incidence of refractory CIP is high among patients with CIP. An increased LDH level at CIP onset is independently associated with refractory CIP. Monitoring LDH levels during immune checkpoint inhibitors treatment is recommended.

Immune Checkpoint Inhibitor Rechallenge and Resumption: a Systematic Review

PURPOSE OF THE REVIEW

The reintroduction of immune checkpoint inhibitors (ICIs) after disease progression (rechallenge) or immune-related adverse events (irAEs) recovering (resumption) raises questions in terms of efficacy and safety.

RECENT FINDINGS

Here, we reviewed literature data about ICIs rechallenge/resumption in cancer patients along with their clinical characteristics to explore those factors associated with better outcomes. Heterogenous results were pointed out across rechallenge studies with an overall response rate between 0 and 54%, and a progression free survival ranged from 1.5 to 12.9 months and an overall survival between 6.5 and 23.8 months. Better outcomes have been recorded in patients with good ECOG PS, longer duration of initial ICI, discontinuation reason of initial ICI other than progression, and those who received ICI sequence other than the switch between anti-PD1 and anti-PDL1. Studies about ICI resumption highlighted that certain types of irAEs were more likely to relapse at retreatment. These results suggest that ICI rechallenge/resumption can be an interesting strategy for selected patients.

Safety of Immune Checkpoint Inhibitor Resumption after Interruption for Immune-Related Adverse Events, a Narrative Review

Immune checkpoint inhibitors (ICIs) have become the standard of care for several types of cancer due to their superiority in terms of survival benefits in first- and second-line treatments compared to conventional therapies, and they present a better safety profile (lower absolute number of grade 1-5 adverse events), especially if used in monotherapy. However, the pattern of ICI-related adverse events is totally different, as they are characterized by the development of specific immune-related adverse events (irAEs) that are unique in terms of the organs involved, onset patterns, and severity. The decision to resume ICI treatment after its interruption due to irAEs is challenged by the need for tumor control versus the risk of occurrence of the same or different irAEs. Studies that specifically assess this point remain scarce, heterogenous and mostly based on small samples of patients or focused only on the recurrence rate of the same irAE after ICI resumption. Moreover, patients with grade ≥3 irAEs were excluded from many of these studies. Herein, we provide a narrative review on the field of safety of ICI resumption after interruption due to irAE(s).

Tocilizumab for the treatment of immune-related adverse events: a systematic literature review and a multicentre case series

OBJECTIVE

Research is moving towards a more personalized management of immune-related adverse events (irAEs) due to immune checkpoint inhibitors (ICI). Our objective was to evaluate the efficacy and safety of tocilizumab in the treatment of these clinical manifestations.

METHODS

A systematic literature review was performed to retrieve data about the use of tocilizumab in the treatment of irAEs. Additionally, data from cancer patients referred to our Immune-related Adverse Event Clinic and treated with tocilizumab were collected.

RESULTS

Our literature review identified 20 articles and 11 meeting abstracts. Data about 91 cancer patients who received tocilizumab for the treatment of irAEs were collected. In 85% of cases, this therapy was associated with clinical benefit and no case of disease progression was reported. ICI therapy was continued following irAE onset and biologic therapy initiation in only three patients. Five patients developed irAEs upon ICI initiation and were subsequently treated with tocilizumab at our Centre. At a median follow-up of eight months, tocilizumab was safely continued along with ICI in three out of five patients, and an adequate control of irAE was obtained in all cases. No significant adverse reactions to tocilizumab were reported. Only one patient experienced a disease progression 18 months after ICI discontinuation.

CONCLUSION

Both our systematic literature review and case series highlight the efficacy and safety of tocilizumab in the treatment of irAEs. Furthermore, they both support the possibility of a combined approach with tocilizumab and ICI, to guarantee an effective irAEs management without losing the oncologic response.

Pulmonary Toxicities Associated With the Use of Immune Checkpoint Inhibitors: An Update From the Immuno-Oncology Subgroup of the Neutropenia, Infection & Myelosuppression Study Group of the Multinational Association for Supportive Care in Cancer

The development of immune checkpoint inhibitors (ICIs) has revolutionized cancer treatment, with agents such as nivolumab, pembrolizumab, and cemiplimab targeting programmed cell death protein-1 (PD-1) and durvalumab, avelumab, and atezolizumab targeting PD-ligand 1 (PD-L1). Ipilimumab targets cytotoxic T lymphocyte-associated antigen-4 (CTLA-4). These inhibitors have shown remarkable efficacy in melanoma, lung cancer, urothelial cancer, and a variety of solid tumors, either as single agents or in combination with other anticancer modalities. Additional indications are continuing to evolve. Checkpoint inhibitors are associated with less toxicity when compared to chemotherapy. These agents enhance the antitumor immune response and produce side- effects known as immune-related adverse events (irAEs). Although the incidence of immune checkpoint inhibitor pneumonitis (ICI-Pneumonitis) is relatively low, this complication is likely to cause the delay or cessation of immunotherapy and, in severe cases, may be associated with treatment-related mortality. The primary mechanism of ICI-Pneumonitis remains unclear, but it is believed to be associated with the immune dysregulation caused by ICIs. The development of irAEs may be related to increased T cell activity against cross-antigens expressed in tumor and normal tissues. Treatment with ICIs is associated with an increased number of activated alveolar T cells and reduced activity of the anti-inflammatory Treg phenotype, leading to dysregulation of T cell activity. This review discusses the pathogenesis of alveolar pneumonitis and the incidence, diagnosis, and clinical management of pulmonary toxicity, as well as the pulmonary complications of ICIs, either as monotherapy or in combination with other anticancer modalities, such as thoracic radiotherapy.