Management and Outcomes of Hematological Immune-related Adverse Events: Systematic Review and Meta-analysis

Data regarding clinical outcomes and management of hematological manifestations of immune checkpoint inhibition (ICI) is limited to case reports, series, and a few retrospective reviews. We aimed to determine the rate of response of hematological immune-related adverse events (irAEs) to immunosuppressive therapy. MEDLINE (OVID), EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) were searched from inception to the present day. Retrospective reports were included without language restrictions. The risk of bias was evaluated with the Cochrane Collaboration's tool. The primary outcome of this study was the rate of response to immunosuppression. Eighty studies (14 case series and 66 individual case reports) were analyzed with a total of 135 patients with ICI-related hematological irAEs. Data analysis showed an average proportional response rate to immunosuppression among hematological irAE entities of 50% (range: 25%-70%). The heterogeneity index (I2) was 0% among reports within each entity. There is a wide spectrum of hematological manifestations to ICI therapy, and to date there is no large randomized-controlled trial data to evaluate the efficacy of treatment strategies for hematological irAEs. We found a variable overall response rate to immunosuppression therapy of around 50%, without statistically significant heterogeneity among different irAE types but significant differences among the different countries of publication. Future studies evaluating the optimal dose and duration of immunosuppressive agents for patients with hematological irAEs should be undertaken.

Clinical features of drug-induced hypersensitivity syndrome to BRAF inhibitors with and without previous immune checkpoint inhibition: a review

PURPOSE

Cutaneous reactions to BRAF inhibitors are common, but severe reactions resembling or consistent with drug-induced hypersensitivity syndrome (DIHS)/drug reaction with eosinophilia and systemic symptoms (DRESS) are relatively rare. Several reports suggest that cutaneous reactions including DRESS/DIHS to BRAF inhibitors are more frequent and severe in the setting of previous immune checkpoint inhibition (ICI).

METHODS

To characterize existing literature on these reports, we queried the PubMed/MEDLINE database for cases of DIHS/DRESS to BRAF inhibitors.

RESULTS

We identified 23 cases of DIHS to BRAF inhibitors following checkpoint inhibition and 14 cases without prior checkpoint inhibitor therapy. In both cohorts, DIHS occurred relatively early, with median time to onset from drug exposure of 8-10 days. Patients who received prior ICI were less likely to have peripheral eosinophilia (26% vs 71%), atypical lymphocytes (9% vs 50%), renal involvement (61% vs 79%), hepatic involvement (52% vs 86%), and lymphadenopathy (9% vs 43%) compared to patients who did not receive prior ICI. Thrombocytopenia was more common with prior ICI (17% vs 7%). Only patients who received prior ICI experienced hypotension (26%) during the course of their DIHS. All cases of BRAF-induced DIHS generally improved on systemic steroids/supportive care, and no cases of death were identified.

CONCLUSION

Dermatologists should consider a diagnosis of DIHS following BRAF inhibitor initiation, particularly in the setting of past checkpoint inhibition, with atypical features including relatively rapid onset and steroid responsiveness, lack of peripheral eosinophilia, lymphocytosis, or lymphadenopathy, and increased risk of thrombocytopenia and hypotension.

Hemophagocytic lymphohistiocytosis in advanced melanoma treated with dabrafenib and trametinib combination: two cases

Hemophagocytic lymphohistiocytosis (HLH) has been only rarely reported in patients with BRAF-mutated advanced melanoma treated with targeted therapies and never with first-line dabrafenib/trametinib combination thus far. Two patients treated with first-line dabrafenib and trametinib combination therapy for metastatic melanoma presented with sudden occurrence of fever, cytopenia, rhabdomyolysis, hepatic cytolysis, hypertriglyceridemia and very high ferritin levels after few weeks of treatment, associated with concomitant epstein-barr virus (EBV) reactivation in one patient. In both cases, drug-induced HLH was primarily considered owing to a high H-score and the absence of other etiology. Patients rapidly improved after treatment discontinuation associated with oral steroids in one patient and did not relapse after subsequent treatment resumption with a concurrent anti-BRAF/anti-MEK combination. In metastatic melanoma HLH may occur either spontaneously in the absence of any treatment as a paraneoplastic condition, related to an intercurrent infection or drug-induced mainly with various immunotherapy or with dabrafenib and trametinib following immunotherapy. However, such observations are scarce and these are the first cases of HLH occurring during first-line treatment with dabrafenib and trametinib in advanced melanoma to our knowledge. Pathomechanisms remain to be elucidated since triggering factors may encompass the treatment itself but also other significant actors including viral reactivation along with the underlying disease. The liability of treatment should be considered in cases of HLH occurring in patients with advanced melanoma successfully treated with a combined targeted therapy. A rechallenge with a concurrent anti-BRAF/anti-MEK can be proposed in this setting.

Hemophagocytic lymphohistiocytosis of a melanoma patient under BRAF/MEK-inhibitor therapy following anti-PD1 inhibitor treatment: a case report and review to the literature

Hemophagocytic lymphohistiocytosis (HLH) is a rare but life-threatening condition. HLH in infants and young children is usually inherited, which is then classified as primary HLH. Secondary HLH, in contrast, is caused by many different conditions such as infections, cancer or medication and affects mostly adults. HLH is a hyperinflammatory condition, which may mimic an acute septic shock. We report on a 68-year-old patient with malignant melanoma with lymph node metastases. Due to the lymphogenic progression, treatment was switched from nivolumab to dabrafenib and trametinib. Twenty-one days after initiation of BRAF/MEK inhibitor therapy, the patient presented to our emergency department with clinical signs of infection such as fever and fatigue. Laboratory tests showed excessive inflammation levels without identifying an underlying pathogen. Two days later, the patient developed an increasing pancytopenia. After extending the diagnosis, we found very high ferritin levels, hypertriglyceridemia, hypofibrinogenemia and a soluble CD25 receptor. Based on the laboratory results, prolonged fever and splenomegaly, we were able to diagnose HLH as the underlying condition. We immediately initiated treatment with intravenous prednisone, which remarkably improved the clinical symptoms. After full recovery, we reinitiated anti-tumor treatment with vemurafenib and cobimetinib, which was tolerated without side effects. Due to the relatively nonspecific nature of the clinical signs and symptoms and the significant overlap with other diseases such as sepsis, the diagnosis of HLH is often delayed. This explains, in part, the high morbidity and mortality rate. Our case shows that early treatment with steroids is effective. However, much work remains in order to raise awareness and improve the understanding of the pathophysiology of this condition.

Haematological immune-related adverse events with immune checkpoint inhibitors, how to manage?

Immune checkpoint inhibitors (ICIs) are changing the treatments of many patients with cancer. These immunotherapies are generally better tolerated than chemotherapy, and their adverse events are immune-related mimicking autoimmune or inflammatory conditions. Although these immune-related adverse events mainly affect the skin, endocrine glands, digestive tract, joints, liver or lungs, all the organs can be theoretically affected, and the haematopoietic system is not spared. This review of the literature will focus on the haematological immune-related adverse events (Haem-irAEs). By reviewing the largest clinical trials of ICIs, we estimate the frequency of Haem-irAEs at 3.6% for all grades and 0.7% for grades III-IV. Frequency of Haem-irAEs of all grades was found to be higher with anti-programmed cell death 1 (4.1%) or anti-programmed cell death ligand 1 (4.7%) than with anti-cytotoxic T-lymphocyte-associated protein 4 (0.5%) (p < 0.0001). From the 63 cases with Haem-irAEs reported in the literature, the mean time to the onset was found to be 10 weeks after ICI initiation, and the large range for occurrence (1-84 weeks) and the regular incidence suggest that Haem-irAEs could occur at any time after ICI therapy. Among the 63 reported cases with Haem-irAEs, the distribution was immune thrombocytopenia (n = 18, 29%), pancytopenia or immune aplastic anaemia (n = 12, 19%), neutropenia (n = 11, 17%), haemolytic anaemia (n = 10, 16%), cytokine release syndrome with haemophagocytic syndrome (n = 7, 11%) and other Haem-irAEs including bicytopenia or pure red cell aplasia (n = 5, 8%). Haem-irAEs are generally highly severe adverse reactions with a mortality rate of Haem-irAEs reported to be 14% (9 deaths among the 63 cases reported). The more severe and life-threatening Haem-irAEs were both cytokine release syndrome with haemophagocytic syndrome and pancytopenia or aplastic anaemia. Haem-irAEs induced by ICIs are potentially life-threatening. By discussing their pathophysiological aspects and clinical picture, we propose in this review clinical guidelines for management.

Cutaneous adverse reactions in B-RAF positive metastatic melanoma following sequential treatment with B-RAF/MEK inhibitors and immune checkpoint blockade or vice versa. A single-institutional case-series

BACKGROUND

With the advent of immune-checkpoint inhibitors and targeted treatments (TT), there have been unprecedented response rates and survival in advanced melanoma, but the optimal sequencing of these two treatments modalities is unknown. Combining or sequencing these agents could potentially result in unique toxicities. Cutaneous adverse events (CAE) after sequential exposure to these agents represents one toxicity that needs further description.

METHODS

After retrospectively reviewing charts of patients from 2015 to 2018, we identified six patients who experienced CAEs after recent exposure to sequential immunotherapy and TT or vice versa for the treatment for metastatic melanoma at the University of North Carolina, Chapel Hill. Skin biopsies were available in five patients.

RESULTS

Five patients received TT after immunotherapy, and one patient received immunotherapy after TT. TT consisted of vemurafenib/cobimetinib (V/C) in five patients with four patients starting V/C immediately before manifesting with a CAE. In patients receiving V/C after immunotherapy, the median time from beginning V/C to development of CAE was 14.5 days. The clinical presentation of diffuse morbilliform rash, fevers, hypotension, and end-organ damage raised concern for Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS) syndrome. Histopathological features of lympho-eosinophilic infiltrate were supportive of a drug eruption. Immunotherapy or TT were re-initiated in five patients within 1-8 weeks after resolution of the index CAE. This resulted in two patients re-experiencing the CAE. Both of these patients were off prednisone at the time of therapy re-initiation, whereas none of the patients who were restarted on targeted therapy with a steroid overlap had a rash recurrence.

CONCLUSIONS

Sequential treatment using immunotherapy and TT, especially the sequence of V/C after immunotherapy appears to be the most common trigger for CAE with a median time to onset of approximately 2 weeks. Although the clinical presentation of these CAEs can be dramatic, they respond well to prednisone therapy. This unique presentation suggests that it may be reasonably safe to re-challenge certain patients with a steroid overlap after rash resolution.