Association of PD-L1 expression with driver gene mutations and clinicopathological characteristics in non-small cell lung cancer: A real-world study of 10 441 patients.

BACKGROUND: Programmed death ligand-1 (PD-L1) expression is a well-known predictive biomarker of response to immune checkpoint blockade in non-small cell lung cancer (NSCLC). However, there is limited evidence of the relationship between PD-L1 expression, clinicopathological features, and their association with major driver mutations in NSCLC patients in Latin America. METHODS: This retrospective study included patients from Argentina with advanced NSCLC, and centralized evaluation of PD-L1 expression concurrently with genomic alterations in the driver genes EGFR, ALK, ROS1, BRAF, and/or KRAS G12C in FFPE tissue samples. RESULTS: A total of 10 441 patients with advanced NSCLC were analyzed. Adenocarcinoma was the most frequent histological subtype (71.1%). PD-L1 expression was categorized as PD-L1 negative (45.1%), PD-L1 positive low-expression 1%-49% (32.3%), and PD-L1 positive high-expression ≥50% (22.6%). Notably, current smokers and males were more likely to have tumors with PD-L1 tumor proportion score (TPS) ≥50% and ≥ 80% expression, respectively (p < 0.001 and p = 0.013). Tumors with non-adenocarcinoma histology had a significantly higher median PD-L1 expression (p < 0.001). Additionally, PD-L1 in distant nodes was more likely ≥50% (OR 1.60 [95% CI: 1.14-2.25, p < 0.01]). In the multivariate analysis, EGFR-positive tumors were more commonly associated with PD-L1 low expression (OR 0.62 [95% CI: 0.51-0.75], p < 0.01), while ALK-positive tumors had a significant risk of being PD-L1 positive (OR 1.81 [95% CI: 1.30-2.52], p < 0.01). CONCLUSIONS: PD-L1 expression was associated with well-defined clinicopathological and genomic features. These findings provide a comprehensive view of the expression of PD-L1 in patients with advanced NSCLC in a large Latin American cohort.

Impact of Lung Cancer on Health-Related Quality of Life, Financial Toxicity, and Household Economics in Patients From the Public and the Private Healthcare Sector in Argentina.

OBJECTIVES: Non-small cell lung cancer (NSCLC) is Argentina's first cause of cancer death. Most patients have an advanced stage at diagnosis, with poor expected survival. This study aimed to characterize the health-related quality of life (HRQOL) and economic impact of patients treated in the private healthcare sector and compare it with that of the public sector. METHODS: We undertook an observational cross-sectional study that extended a previous study to a referral private center in Argentina. Outcomes included the EuroQol EQ-5D-3L (to assess HRQOL), Comprehensive Score for Financial Toxicity (financial toxicity instrument), Work Productivity and Activity Impairment - General Health (to assess productivity loss), and out-of-pocket expenses in adults diagnosed of NSCLC. RESULTS: We included 30 consecutive patients from a private healthcare center (July 2021 to March 2022), totaling 131 patients (n = 101 from previous public study). The whole sample had low quality of life and relevant economic impact. Patients in the private healthcare sector showed lower disease severity and higher educational level and household income. In addition, private healthcare system patients showed higher utility (0.77 vs 0.73; P < .05) and lower impairment of daily activities (41% vs 59%; P = .01). Private health system patients also showed lower financial toxicity as measured by the Comprehensive Score for Financial Toxicity score (23.9 vs 20.14; P < .05) but showed no differences when financial toxicity was assessed as a dichotomic variable. CONCLUSIONS: Although patients with NSCLC treated in a private healthcare center in Argentina showed a relevant HRQOL and economic impact, this impact was smaller than the one observed in publicly funded hospitals.

Overcoming Resistance to Osimertinib by T790M Loss and C797S Acquisition Using Gefitinib in a Patient With EGFR-Mutant NSCLC: A Case Report.

Limited strategies are available at disease progression on osimertinib for patients with EGFR-mutant NSCLC. The emergence of the on-target EGFR C797S mutation has been described as one of the most common mechanisms of resistance. In addition, loss of the EGFR T790M mutation has been mainly investigated as a resistance phenomenon to second-line osimertinib exposure. Remarkably, by studying the molecular profile at progression, it has been reported that the presence of the EGFR-sensitizing mutation, concurrently with the T790M, and C797S resulted in resistance to the current available EGFR tyrosine kinase inhibitors. Here, we report the first clinical evidence of gefitinib efficacy at EGFR exon 19 deletion/C797S mutation/T790M loss-mediated resistance to first-line osimertinib. Our findings highlight that dynamic genetic monitoring is a crucial approach in the evolution of EGFR-mutant NSCLC to understand the acquired molecular mechanisms for driving the best treatment strategy.

Characteristics and outcomes of thymomas in Latin America: Results from over 10 years of experience (CLICaP-LATimus).

BACKGROUND: Thymomas are a group of rare neoplasms of the anterior mediastinum. The objective of this study was to describe the demographics, clinical characteristics and treatment approaches in Latin America. METHODS: This was a retrospective multicenter cohort study including patients with histologically proven thymomas diagnosed between 1997 and 2018. Demographics, clinicopathological characteristics and therapeutic outcomes were collected locally and analyzed in a centralized manner. RESULTS: A total of 135 patients were included. Median age at diagnosis was 53 years old (19-84), 53.3% (n = 72) of patients were female and 87.4% had an ECOG performance score ranging from 0-1. A total of 47 patients (34.8%) had metastatic disease at diagnosis. Concurrent myasthenia gravis occurred in 21.5% of patients. Surgery was performed in 74 patients (54.8%), comprising 27 (20%) tumorectomies and 47 (34.8%) thymectomies. According to the Masaoka-Koga system, overall survival (OS) at five-years was 73.4%, 63.8% and 51%, at stages I-II, III-IVA and IVB, respectively (p = 0.005). Furthermore, patients with low lactate dehydrogenase (LDH) (≤373 IU/L) at baseline and myasthenia gravis concurrence showed significantly better OS (p = 0.001 and p = 0.008, respectively). In multivariate analysis, high LDH levels (HR 2.8 [95% confidence interval [CI]: 1.1-7.8]; p = 0.036) at baseline and not performing a surgical resection (HR 4.1 [95% CI: 1.3-12.7]; p = 0.016) were significantly associated with increased risk of death. CONCLUSIONS: Our data provides the largest insight into the clinical characteristics and outcomes of patients with thymomas in Latin America. Survival in patients with thymomas continues to be very favorable, especially when subjected to adequate local control.

Implementation of a molecular tumour board in LATAM: the impact on treatment decisions for patients evaluated at Instituto Alexander Fleming, Argentina.

BACKGROUND: The role of the molecular tumour board (MTB) is to recommend personalised therapy for patients with cancer beyond standard-of-care treatment. A comprehensive molecular analysis of the tumour in a molecular pathology laboratory is important for all targeted therapies approaches. Here we report the 1-year experience of the Instituto Alexander Fleming Molecular Tumour Board. PATIENTS AND METHODS: The MTB of the Instituto Alexander Fleming was launched in December 2019 in a monthly meeting. In each interactive monthly session, five cases were presented and discussed by the members. These cases were referred by the treating oncologists. The MTB recommendations were sent to each physician individually, and to the rest of the meeting participants. This was discussed with the patients/families by the treating oncologist. The final decision to choose therapy was left to the treating physicians. Of the 32 patients presented at MTB, 28 (87.5%) had potentially actionable alterations and only 4 (12.5%) had no actionable mutation. Six (19%) patients received a local regulatory agency approved drug recommendation, nine (28%) patients received an off-label approval treatment recommendation and three (9%) patients did not receive the treatment due to access and reimbursement of the drug. CONCLUSION: In most of the cases evaluated, the MTB was able to provide treatment recommendations based on targetable genetic alterations. Molecular-guided extended personalised patient care is effective for a small but clinically significant proportion of patients in challenging clinical situations. We believe that the implementation of a MTB is feasible in the Latin America (LATAM) region.

Efficacy and Safety of Nivolumab in Previously Treated Patients With Non-Small-cell Lung Cancer: Real World Experience in Argentina.

BACKGROUND: Nivolumab was the first anti-programmed cell death 1 drug approved in Argentina for non-small-cell lung cancer treatment in the second-line setting. MATERIALS AND METHODS: The present study was a multicenter, observational, retrospective study of patients with progression to stage IV NSCLC during platinum-based chemotherapy who had received nivolumab monotherapy in a drug-expanded access program in Argentina. RESULTS: The data from 109 patients were assessed retrospectively for safety and clinical outcomes. The follow-up period was 8.83 months (interquartile range, 3.4-12.67); 57.8% were men, 29.4% were current smokers, and 78.0% had a diagnosis of nonsquamous cell cancer. The median number of chemotherapy lines before nivolumab was 2 (range, 1-4). Also, 59.6% had received radiotherapy and 89% had received platinum-based chemotherapy. The drug-related toxicity rate was 78.9%, the grade 2-3 toxicity rate was 28.4%, and 33.9% of patients had required corticosteroids. The treatment response was evaluated in 104 patients. The best response was a complete response in 2 (2%), partial response in 28 (27%), stable disease in 33 (32%), and progressive disease in 41 (39%). Univariate analysis revealed that the absence of corticosteroid use (P = .034), toxicity grade 1-3 (P = .0025), and performance status of ≤ 1 (P = .049) were associated with longer disease-free survival, performance status of ≤ 1 (P < .001), and toxicity grade 1-3 (P = .001) were associated with longer overall survival. On multivariate Cox regression analysis, toxicity grade 1-3 (hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.24-0.81; P = .008) and age ≤ 50 years (HR, 0.28; 95% CI, 0.13-0.61; P = .001) were associated with longer progression-free survival and corticosteroid use was associated with shorter progression-free survival (HR, 2.06; 95% CI, 1.22-3.48; P = .007). CONCLUSIONS: The use of nivolumab in the real world setting in patients with heavily pretreated NSCLC was well tolerated and showed promising clinical efficacy. The performance status, use of corticosteroids, and immune-mediated toxicity seem to be the conditions that can affect the clinical outcomes.

Peripheral changes in immune cell populations and soluble mediators after anti-PD-1 therapy in non-small cell lung cancer and renal cell carcinoma patients.

Patients with non-small cell lung cancer (NSCLC) and renal cell carcinoma (RCC) have shown benefit from anti-PD-1 therapies. However, not all patients experience tumor shrinkage, durable responses or prolonged survival, demonstrating the need to find response markers. In blood samples from NSCLC and RCC patients obtained before and after anti-PD-1 treatment, we studied leukocytes by complete blood cell count, lymphocyte subsets using flow cytometry and plasma concentration of nine soluble mediators, in order to find predictive biomarkers of response and to study changes produced after anti-PD-1 therapy. In baseline samples, discriminant analysis revealed a combination of four variables that helped differentiate stable disease-response (SD-R) from progressive disease (PD) patients: augmented frequency of central memory CD4+ T cells and leukocyte count was associated with response while increased percentage of PD-L1+ natural killer cells and naïve CD4+ T cells was associated with lack of response. After therapy, differential changes between responders and non-responders were found in leukocytes, T cells and TIM-3+ T cells. Patients with progressive disease showed an increase in the frequency of TIM-3 expressing CD4+ and CD8+ T cells, whereas SD-R patients showed a decrease in these subsets. Our findings indicate that a combination of immune variables from peripheral blood (PB) could be useful to distinguish response groups in NSCLC and RCC patients treated with anti-PD-1 therapy. Frequency of TIM-3+ T cells showed differential changes after treatment in PD vs SD-R patients, suggesting that it may be an interesting marker for monitoring progression during therapy.

Uso de inhibidores de tirosina quinasa en carcinoma medular de tiroides. Experiencia Institucional / Use of tyrosine kinase inhibitors in medullary thyroid carcinoma. Institutional Experience

El cáncer medular de tiroides (CMT) correspondeal 5% de los tumores de la glándula tiroides. El único tratamiento curativo es la cirugía. En pacientes con compromiso locorregional o a distancia, la enfermedad puede evolucionar en forma indolente o bien con una rápida progresión de síntomas, requiriendo tratamiento sistémico. Si bien el CMT se caracteriza por tener escasa respuesta a la quimioterapia (QT), la evidencia actual en estudios aleatorizados demostró que los inhibidores de tirosina quinasa (ITQ) han demostrado beneficio en supervivencia libre de progresión (SLP). Se analizaron 6 pacientes con un seguimiento mediano de 29 meses. Todos presentaron más de dos sitios metastásicos. Dos requirieron tratamientos locorregionales (quimioembolización y RT). Los ITQ más utilizados fueron: vandetanib (3), sorafenib (2) y sunitinib (1). Un 50% inició tratamiento con dosis plenas y 3 requirieron reducción de dosis debido a toxicidad G3-G4. El intervalo libre de progresión (ILP) mediano, luego del inicio con ITQ, fue de 4.1 meses (AU)

Medullary thyroid cancer (CMT) accounts for 5% of thyroid tumors. The only curative treatment is surgery. In patients with locally or distal involvement, the disease may evolve indolently or with rapid progression of symptoms, requiring systemic treatment. Although CMT is characterized by a poor response to chemotherapy, current evidence in randomized trials has shown that tyrosine kinase inhibitors (ITKs) have demonstrated benefit in progressionfree survival. Six patients with a median follow-up of 29 months were analyzed. All had more than two metastatic sites. Two patients required locoregional treatments (chemoembolization and radio therapy). The most commonly used ITKs were: vandetanib (3), sorafenib (2) and sunitinib (1). The 50% initiated treatment with full dose and 3 required reduction of the dose due to G3- G4 toxicity. The median progression-free interval after initiation with ITK was 4.1 months (AU)