A case of hyperprogressive disease following atezolizumab therapy for pulmonary pleomorphic carcinoma with epidermal growth factor receptor mutation

Biological characteristics and clinical treatment of pulmonary sarcomatoid carcinoma: a narrative review

Background and Objective

Pulmonary sarcomatoid carcinoma (PSC) is a subset of non-small cell lung cancer (NSCLC) with highly malignant, aggressive, and heterogeneous features. Patients with this disease account for approximately 0.1-0.4% of lung cancer cases. The absence of comprehensive summaries on the basic biology and clinical treatments for PSC means there is limited systematic awareness and understanding of this rare disease. This paper provides an overview of the biological characteristics of PSC and systematically summarizes various treatment strategies available for patients with this disease.

Methods

For this narrative review, we have searched literature related to the basic biology and clinical treatment approaches of PSC by searching the PubMed database for articles published from July 16, 1990 to August 29, 2023. The following keywords were used: "pulmonary sarcomatoid carcinoma", "genetic mutations", "immune microenvironment", "hypoxia", "angiogenesis", "overall survival", "surgery", "radiotherapy", "chemotherapy", and "immune checkpoint inhibitors".

Key Content and Findings

Classical PSC comprises epithelial and sarcomatoid components, with most studies suggesting a common origin. PSC exhibits a higher tumor mutational burden (TMB) and mutation frequency than other types of NSCLC. The tumor microenvironment (TME) of PSC is characterized by hypoxia, hypermetabolism, elevated programmed cell death protein 1/programmed cell death-ligand 1 expression, and high immune cell infiltration. Treatment strategies for advanced PSC are mainly based on traditional NSCLC treatments, but PSC exhibits resistance to chemotherapy and radiotherapy. The advancement of genome sequencing has introduced targeted therapies as an option for mutation-positive PSC cases. Moreover, due to the characteristics of the immune microenvironment of PSC, many patients positively respond to immunotherapy, demonstrating its potential for the management of PSC.

Conclusions

Although several studies have examined and assessed the TME of PSC, these are limited in quantity and quality, presenting challenges for research into the clinical treatment strategies for PSC. With the emergence of new technologies and the advancement of clinical research, for example, savolitinib's clinical study for MET exon 14 skipping mutations positive PSC patients have shown promising outcomes, more in-depth studies on PSC are eagerly anticipated.

Extremely high infiltration of CD8+PD-L1+ cells detected in a stage III non-small cell lung cancer patient exhibiting hyperprogression during anti-PD-L1 immunotherapy after chemoradiation: A case report

In recent years, immune checkpoint inhibitors (ICIs), represented by PD-1/PD-L1 monoclonal antibodies, have become a research hotspot in the field of oncology treatment. Immunotherapy has shown significant survival advantages in a variety of solid tumors. However, the phenomenon of hyperprogressive disease (HPD) in some patients treated with immunotherapy is gradually getting more attention and focus. An early understanding of the characteristics of HPD is crucial to optimize the treatment strategy. We report a patient with unresectable stage III lung adenocarcinoma who developed HPD with metastasis during consolidation therapy with durvalumab after chemoradiation. To further investigate the potential mechanism of HPD after anti-PD-L1 treatment, primary lung baseline tissue, baseline plasma, post-immunotherapy plasma, and liver metastasis samples of the patient were detected via next-generation sequencing (NGS). Then, multiplex immunohistochemistry (mIHC) was performed on primary lung baseline tissue and liver metastasis samples. KRAS and p.G12C were identified as the major driver mutation genes. With a low tumor mutation burden (TMB) value, the patient presented a very high percentage of CD8+PD-L1+ T cells that infiltrated in the baseline tissue, with 95.5% of all CD8+ cells expressing PD-L1 and a low percentage of CD8+ T cells expressing PD-1. After the emergence of HPD from immunotherapy, liver metastases were similarly infiltrated with an extremely high proportion of CD8+PD-L1+ T cells, with 85.6% of all CD8+ cells expressing PD-L1 and almost no CD8+ T cells expressing PD-1. The extreme infiltration of PD-L1+CD8+ T cells in the tumor microenvironment of baseline tissue might be associated with the aggressive tumor growth observed in anti-PD-L1 treatment for related HPD and could be a potential biomarker for HPD development.

EGFR mutations and high PD-L1 expression of lung squamous cell carcinoma patients achieving pCR following neoadjuvant immuno-chemotherapy: Case report

The treatment of lung cancer has fully entered the era of immunotherapy, which has significantly elevated the survival rate of patients with advanced non-small cell lung cancer (NSCLC), thus shedding light on resectable NSCLC. Previous clinical trial data suggested that neoadjuvant immuno-chemotherapy obtained a significant objective response rate (ORR) and disease control rate (DCR). Here, a case that achieved an excellent outcome following neoadjuvant immuno-chemotherapy was reported. The patient admitted to our hospital was 58 years old, female, with a rare case of stage IB lung squamous cell carcinoma (LUSC) harboring both epidermal growth factor receptor (EGFR) p.L858R mutations and high expression of programmed death ligand-1 (PD-L1) (tumor proportion score (TPS)=80%). Her tumor substantially shrunk following two cycles of neoadjuvant immuno-chemotherapy. The patient successively received single-port right upper thoracoscopic lobectomy + mediastinal lymph node dissection, which attained pathologic complete response (pCR). Additionally, the patient had grade 2 myelosuppression during the two cycles, which was treated with polyethylene glycol recombinant human granulocyte colony-stimulating factor (rhG-CSF). The patient was discharged uneventfully without any procedure-related complications. Two courses of adjuvant immuno-chemotherapy were administered postoperatively, leaving the patient in good physical condition at the 5-month follow-up visit. This case provided evidence for the feasibility and effectiveness of neoadjuvant immuno-chemotherapy in treating early-stage LUSC with EGFR mutations and high expression of PD-L1. However, randomized and multi-center controlled trials are required to validate the findings.

Features of patients with advanced EGFR-mutated non-small cell lung cancer benefiting from immune checkpoint inhibitors

Background

Although immune checkpoint inhibitors (ICIs) generally show poor therapeutic efficacy in patients with epidermal growth factor receptor (EGFR) mutations, certain research indicate that a small proportion of these patients do respond to ICIs. The present study sought to identify the features of patients with EGFR mutations who might benefit from ICIs from multiple studies and discussed the optimal treatment paradigm for advanced non-small cell lung cancer (NSCLC) patients with EGFR mutations.

Methods

The profiles of 114 advanced NSCLC patients with EGFR mutations who received ICIs treatment were retrospectively reviewed. EGFR subtypes, programmed cell death ligand 1 (PD-L1) expression, and clinical characteristics regarding their impact on the efficacy of ICIs were investigated.

Results

Patients with major EGFR mutations (L858R or 19Del) had a shorter progression-free survival (PFS) and a lower objective response rate (ORR) as compared to patients with rare (20ins or G719X) and other EGFR mutations. Although not statistically significant, median overall survival (OS) tended to be longer in patients with negative (<1%) PD-L1 expression than with positive (≥1%) PD-L1 expression (15.61 vs. 7.40 months, p = 0.138). Median PFS and OS were significantly shorter in heavily treated patients (prior lines of therapy ≥3 lines vs. <3 lines: mPFS, 1.80 vs. 2.50 months, p = 0.003; mOS, 6.70 vs. 14.00 months, p = 0.031). ORR was also lower in patients who had received ≥3 prior lines of therapy compared to in those <3 prior lines of therapy (0.00% vs. 21.67%, p = 0.002).

Conclusion

Patients with major EGFR mutations showed poorer responses to ICIs than those with rare EGFR mutations. EGFR-mutated patients with lower PD-L1 expression showed a trend towards a longer OS after receiving ICIs. ICIs should be administered as early as possible to previously treated EGFR-mutated NSCLC patients. ICI-based combined therapies may be a direction for treatment of these patient subtypes in the future.

Pulmonary Pleomorphic Carcinoma Harboring EGFR Mutation Successfully Treated with Osimertinib: A Case Report

Pulmonary pleomorphic carcinoma (PPC) is well-known for its aggressive nature that is usually resistant to platinum-based chemotherapy. On the other hand, the efficacy of an immune checkpoint inhibitor-based regimen in PPC has been elucidated. PPCs harboring epidermal growth factor receptor (EGFR) mutations are extremely rare, and the efficacy of EGFR-tyrosine kinase inhibitors in PPC is limited compared to their efficacy in EGFR-mutated adenocarcinoma. A 43-year-old female patient presenting with a lung mass with multiple brain metastases, carcinomatous pericarditis, and multiple bone metastases was referred to our department. Transbronchial biopsy confirmed the diagnosis of PPC harboring an EGFR mutation with exon 19 deletion. Subsequently, she was treated with osimertinib, a third-generation EGFR-tyrosine kinase inhibitor, which resulted in partial response with shrinkage of the primary lesion and brain metastases. This partial response remained durable for 11 months with an ongoing regimen. The current case suggests that osimertinib would show promising effects as a first-line treatment for PPCs harboring EGFR mutations, as well as a reasonable sequence of therapy followed by immune checkpoint inhibitor-based regimens.