Efficacy of immune checkpoint inhibitors for the treatment of advanced melanoma in patients with concomitant chronic lymphocytic leukemia

Immunotherapy response in immunosuppressed patients with Merkel cell carcinoma: analysis of 183 patients

Objective

Merkel cell carcinoma (MCC) is an aggressive skin cancer with poor outcomes in immunosuppressed patients. While immune checkpoint inhibitors (ICIs) achieve ~60% response rates in immunocompetent MCC patients, their efficacy in immunosuppressed patients remains unclear due to exclusion from trials. This study compares ICI outcomes, safety and the impact of immunosuppression subtypes between these groups.

Methods and analysis

This retrospective study analysed 183 advanced MCC patients on first-line ICIs from a Seattle-based data repository. Of these, 147 were immunocompetent, and 36 were immunosuppressed (chronic lymphocytic leukaemia (CLL) n=10, autoimmune disorders n=10, other haematologic malignancies n=9, solid organ transplants n=4 and HIV/AIDS n=3). Outcomes included objective response rate, disease progression, MCC-specific and overall survival probability, adjusted for age, sex and stage at ICI initiation.

Results

Initial ICI response rates at 6 months were 50% in immunosuppressed and 61.5% in immunocompetent patients (HR=0.71, p=0.17). Immunosuppressed patients had higher risks of disease progression (2 years: 53.9% vs 42.1%, HR=1.65, p=0.05) and MCC-specific mortality (2 years: 38.7% vs 24.4%, HR=1.85, p=0.04). CLL patients (n=10) had a particularly low response rate (response rate: 20.0% vs 61.5%, HR=0.18, p=0.02) and high progression risk (2 years: 80.0% vs 42.1%, HR=4.09, p=0.01). Immunosuppressed patients faced higher rates of ICI toxicity (6-month risk: 51.6% vs 36.6%, HR=1.79, p=0.03).

Conclusions

ICIs provide meaningful benefits to immunosuppressed MCC patients, though their response rates are lower, and progression risk is higher compared with immunocompetent patients.

Recurrent Melanoma in a Patient with Chronic Lymphocytic Leukemia (CLL) Presenting with an Apparent Co-Existing NRAS and BRAF Mutation: A Diagnostic and Treatment Conundrum

Melanoma is the fifth most common cancer in the United States. The advent of immunotherapy and molecular targeted therapy has improved progression-free and overall survival in many patients with advanced disease. However, the selection of therapeutic choices requires a nuanced approach, especially when considering molecularly targeted agents. This case report highlights a diagnostic and therapeutic challenge in managing a patient with a history of chronic lymphocytic leukemia (CLL) and recurrent melanoma. Molecular testing suggested discordant BRAF V600E testing and a simultaneous NRAS G12D mutation. After a careful literature review, repetition of his molecular testing, and analysis of the timelines and results of all his molecular testing, we concluded that the BRAF V600E mutation result was falsely positive. The patient was treated with two cycles of ipilimumab (1 mg/kg) and nivolumab (3 mg/kg) as per the NADINA trial and had a complete radiographic response. He then underwent resection demonstrating a pathologic partial response ranging from 20% to 95% tumor necrosis, dependent on the satellite examined. This case report underscores the importance of precise molecular diagnostics in guiding melanoma treatment and demonstrates the complexities of managing a patient with a coexisting malignancy.

Clinical and histopathological features of advanced cutaneous squamous cell carcinoma with varying responses to cemiplimab

BACKGROUND

Most patients with unresectable locally advanced cutaneous squamous cell carcinoma (cSCC) benefit from cemiplimab, but some do not respond. Our study aims to identify clinical and histopathological features predicting response to cemiplimab.

PATIENTS AND METHODS

We analyzed 15 patients treated with cemiplimab, assessing clinical, demographic, histopathological, and immunohistochemical characteristics and correlating them with treatment response. Furthermore, effectiveness and safety were evaluated in our cohort.

RESULTS

Our cohort included 12 males and 3 females, with a mean age of 78.1 years. The majority of tumors, accounting for 66.7%, were located in the head and neck region. Treatment was well-tolerated, with only one grade 3 colitis. There was no correlation between immune-related adverse events and treatment response. Non-responders were younger (69.4 vs. 82.5 years). A history of hematological malignancy correlated with poorer response. High mitotic rate, poor tumor differentiation, high vimentin and p53, and low E-cadherin expression were associated with worse response. Conversely, higher intratumoral inflammatory infiltrate density, presence of necrotic areas, and lower mismatch repair-protein staining correlated with better response.

CONCLUSIONS

Cemiplimab is a safe and effective therapy, particularly in elderly patients. Well-differentiated tumors with low proliferative index, intratumoral inflammatory infiltrate, and tumor necrosis may predict better clinical response.

Immunophenotyping of Peripheral Blood Cells in Patients with Chronic Lymphocytic Leukemia Treated with Ibrutinib

Chronic lymphocytic leukemia (CLL) is a B-cell-derived hematologic malignancy whose progression depends on active B-cell receptor (BCR) signaling. Despite the spectacular efficacy of Ibrutinib, an irreversible inhibitor of Bruton tyrosine kinase (BTK), resistance can develop in CLL patients, and alternative therapeutic strategies are therefore required. Cancer immunotherapy has revolutionized cancer care and may be an attractive approach in this context. We speculated that characterizing the immune responses of CLL patients may highlight putative immunotherapeutic targets. Here, we used high-dimensional spectral flow cytometry to compare the distribution and phenotype of non-B-cell immune populations in the circulating blood of CLL patients treated with Ibrutinib displaying a complete response or secondary progression. Although no drastic changes were observed in the composition of their immune subsets, the Ibrutinib-resistant group showed increased cycling of CD8+ T cells, leading to their overabundance at the expense of dendritic cells. In addition, the expression of 11 different surface checkpoints was similar regardless of response status. Together, this suggests that CLL relapse upon Ibrutinib treatment may not lead to major alterations in the peripheral immune response.

A Retrospective Review and Comprehensive Tumour Profiling of Advanced Non-Melanomatous Cutaneous Spindle Cell Neoplasms Treated with Immune-Checkpoint Inhibitors

Non-melanomatous cutaneous spindle cell neoplasms are a rare group of malignancies that present a diagnostic challenge, and for which there is a lack of consensus on how to best manage patients with advanced disease and only limited reports of immune-checkpoint inhibitor (ICI) responses. In this study, we performed a single-center retrospective review of treatment outcomes for all advanced non-melanomatous cutaneous spindle cell neoplasms treated with ICIs. Blinded histopathology reviews occurred to confirm each diagnosis. Comprehensive tumour profiling included whole exome sequencing for tumour mutational burden (TMB) and ultraviolet(UV) signatures, and immunohistochemistry for immune-cell infiltration (CD4/CD3/CD8/CD103/CD20) and immune-checkpoint expression (PD-L1/LAG3/TIGIT). Seven patients were identified. The objective response rate was 86% (6/7) with five complete responses (CR). Responses were durable with two patients in CR > 30 months after ICI commencement. All patients had high TMB and UV signatures. One patient had PD-L1 100% (combined positive score) with abundant immune-cell infiltration and LAG3 expression. In advanced non-melanomatous cutaneous spindle cell neoplasms, excellent responses to ICIs with durable disease control were observed. ICIs are worthy of further exploration in these patients. UV signatures and high TMB could be used to help select patients for treatment.

Cutaneous malignancies in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is a common lymphoid malignancy that is associated with an increased risk of developing cutaneous malignancies. Clinical outcomes for these malignancies, including melanoma and keratinocyte cancers (KC), are worse for patients with CLL. Individuals with CLL develop an immunodeficiency of both the adaptive and innate immune system, which plays a role in the increased prevalence of skin cancers. This review focuses on the complex interplay between genetics, immunity, and pathogens that influence the cellular composition and biology of skin tumors and their microenvironment in CLL patients, and in comparison with other chronic hematological malignancies. It is paramount for dermatologists to be aware of the association between CLL (and chronic hematological malignancies more broadly) and cutaneous malignancies. This is a high-risk population who require regular and vigorous dermatologic follow-up.