Durable response after discontinuation of pembrolizumab therapy for intrahepatic cholangiocarcinoma: a case report

Preclinical and clinical studies of immunotherapy for the treatment of cholangiocarcinoma

Cholangiocarcinoma (CCA) is a rare primary liver cancer associated with high mortality and few systemic treatment options. The behaviour of the immune system has come into focus as a potential treatment modality for many cancer types, but immunotherapy has yet to dramatically alter the treatment paradigm for CCA as it has for other diseases. Herein, we review recent studies describing the relevance of the tumour immune microenvironment (TIME) in CCA. Various non-parenchymal cell types are critically important in controlling CCA progression, prognosis, and response to systemic therapy. Knowledge of the behaviour of these leukocytes could help generate hypotheses to guide the development of potential immune-directed therapies. Recently, an immunotherapy-containing combination was approved for the treatment of advanced-stage CCA. However, despite level 1 evidence demonstrating the improved efficacy of this therapy, survival remained suboptimal. In the current manuscript, we provide a comprehensive review of the TIME in CCA, preclinical studies of immunotherapies against CCA, as well as ongoing clinical trials applying immunotherapies for the treatment of CCA. Particular emphasis is placed on microsatellite unstable tumours, a rare CCA subtype that demonstrates heightened sensitivity to approved immune checkpoint inhibitors. We also discuss the challenges involved in applying immunotherapies to the treatment of CCA and the importance of understanding the TIME.

Analysis of the clinical characteristics of pembrolizumab-induced bullous pemphigoid

Background

Pembrolizumab, a programmed cell death protein 1 checkpoint inhibitor, is a novel drug used to treat a variety of advanced malignancies. However, it can also result in many immune-related adverse events, with cutaneous toxicities being the most frequent. Regarding pembrolizumab-induced skin adverse reactions, bullous pemphigoid (BP) has the worst effects on quality of life. Recently, there have been more and more reports of BP incidents resulting from pembrolizumab therapy in patients with cancer. This study aimed to define the clinical characteristics, diagnosis and management of pembrolizumab-induced BP and identify potential differences between classical BP and pembrolizumab-induced BP.

Methods

Case reports, case series, and case analyses of pembrolizumab-induced BP up to 10 December 2022 were collected for retrospective analysis.

Results

Our study included 47 patients (33 males and 14 females) from 40 studies. The median age was 72 years (range 42-86 years). The median time to cutaneous toxicity was 4 months (range 0.7-28 months), and the median time to bullae formation was 7.35 months (range 0.7-32 months). The most common clinical features were tense bullae and blisters (85.11%), pruritus (72.34%), and erythema (63.83%) on the limbs and trunk. In 20 of the 22 cases tested, the serum anti-BP180 autoantibodies were positive. However, in 10 cases (91.90%, 10/11) the circulating autoantibodies of anti-BP230 were negative. 40 patients had skin biopsies and the skin biopsy revealed subepidermal bullae or blister eosinophil infiltration in 75.00% of patients with pembrolizumab-induced BP, 10.00% of patients with lymphocyte infiltration and 20.00% of patients with neutrophil infiltration. There were 20 patients (50%) with eosinophilic infiltration around the superficial dermis vessels, 8 patients (20.00%) with lymphocyte infiltration around the superficial dermis vessels, and 4 patients (10.00%) with neutrophil infiltration around the superficial dermis vessels. Direct immunofluorescence detected linear immunoglobulin G (IgG) IgG and/or complement C3 along the dermo-epidermal junction in 36 patients (94.74%) with BP. IgG positivity was detected by indirect immunofluorescence in 81.82% of patients with BP. All patients were in complete remission (95.65%,44/46) or partial remission (4.35%, 2/46) of BP, whereas 9/46 patients had a relapse or refractory. The majority of patients achieved BP remission after discontinuation of pembrolizumab with a combination of topically and systemically administered steroid treatments, or other medications. The median duration of BP remission was 2 months (range 0.3-15 months).

Conclusion

A thorough diagnosis of pembrolizumab-induced BP should be made using clinical signs, biochemical markers, histopathological and immunopathological tests. Pembrolizumab-induced BP had similar clinical characteristics to classic BP. Temporary or permanent discontinuation of pembrolizumab therapy may be required in patients with perbolizumab-induced BP depending on the severity of BP and the response to medication. Pembrolizumab-induced BP may be effectively treated using topical and systemic steroid treatments in combination with other medications (e.g., doxycycline, niacinamide, dapsone, rituximab, intravenous immunoglobulins, dupilumab, cyclophosphamide, methotrexate, mycophenolate mofetil, and infliximab). Clinicians should provide better management to patients with BP receiving pembrolizumab to prevent progression and ensure continuous cancer treatment.

Association of Bullous Pemphigoid With Immune Checkpoint Inhibitor Therapy in Patients With Cancer: A Systematic Review

Importance

There is limited information on immune checkpoint inhibitor-induced bullous pemphigoid (ICI-BP) in patients with cancer, with most existing studies being case reports or small case series from a single institution. Prior review attempts have not approached the literature in a systematic manner and have focused only on ICI-BP secondary to anti-programmed cell death 1 (PD-1) or programmed cell death ligand 1 (PD-L1) therapy. The current knowledge base of all aspects of ICI-BP is limited.

Objective

To characterize the risk factors, clinical presentation, diagnostic findings, treatments, and outcomes of ICI-BP in patients with cancer as reported in the current literature.

Evidence Review

A systematic review was performed using PubMed, Embase, Web of Science, and the Cochrane Database of Systematic Reviews according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines. Articles reporting data on individual patients who met preestablished inclusion criteria were selected, and a predefined set of data was abstracted. When possible, study results were quantitatively combined.

Findings

In total, 70 studies reporting data on 127 individual patients undergoing ICI therapy for cancer (median [IQR] age, 71 [64-77] years; 27 women [21.3%]) were included. In pooled analyses, patients ranged in age from 35 to 90 years. Immune checkpoint inhibitor-induced bullous pemphigoid often occurred during the course of anti-PD-1, PD-L1, or cytotoxic T lymphocyte-associated antigen 4 therapy but was also found to develop up to several months after treatment cessation. Prodromal symptoms, such as pruritus or nonspecific skin eruptions, were found in approximately half of the patient population. Histopathologic or serologic testing, when undertaken, was a helpful adjunct in establishing diagnosis. Treatment with immunotherapy was discontinued after ICI-BP development in most patients. The most common treatments were systemic and topical corticosteroids. Steroid-sparing therapies, such as antibiotics and other systemic immunomodulators, were also used as adjuvant treatment modalities. Biologic and targeted agents, used predominantly in cases refractory to treatment with corticosteroids, were associated with marked symptomatic improvement in most patients.

Conclusions and Relevance

The results of this systematic review suggest that ICI-BP often poses a therapeutic challenge for patients with cancer who are receiving immunotherapy. Further research on the early recognition, diagnosis, and use of targeted treatment modalities will be essential in developing more personalized treatment options for affected patients while minimizing morbidity and mortality.

Durable response after the discontinuation of pembrolizumab treatment due to an adverse event in a patient with advanced endometrial cancer: A case report

The persistence of antitumor effects has been reported after the completion of treatment with immune checkpoint inhibitors (ICIs) for various types of carcinoma, such as malignant melanoma, exhibiting a durable response. A durable response has also been noted after the discontinuation of treatment at an early stage due to adverse events, including in renal pelvic cancer, pancreatic cancer and intrahepatic cholangiocarcinoma; however, to the best of our knowledge, a similar case report has not yet been published in the malignant gynecological tumor field. The present study described a patient with refractory advanced endometrial cancer in whom the administration of pembrolizumab was discontinued after the completion of the 7th course due to renal dysfunction; however, persistent tumor-reducing effects and decreases in the levels of tumor markers were noted for more than 18 months after the cessation of treatment. Pembrolizumab may be continuously administered to some patients for a long period, whereas a durable response is achieved by others even after its discontinuation at an early stage; therefore, difficulties are associated with selecting an appropriate duration of administration. Further studies are required to search for biomarkers that facilitate high-accuracy effect predictions, and to establish an optimal administration period in consideration of specific adverse reactions to ICIs and cost-effectiveness.