Liquid biopsy in clinical outcomes and detection of T790M mutation in metastatic non-small cell lung cancer after progression to EGFR-TKI

BACKGROUND

Liquid biopsy (LB) is used to detect epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC) and has been demonstrated to have prognostic and predictive value.

OBJECTIVE

To associate the rates of EGFR and T790M mutations detected by LB during disease progression after first- or second-generation EGFR-TKIs with clinical characteristics and survival outcomes.

METHODS

From January 2018 to December 2021, 295 patients with advanced EGFR mutant (EGFRm) NSCLC treated with first- or second-generation EGFR-TKIs were retrospectively analyzed. LB was collected at the time of progression. The frequency of EGFRT790M mutations, overall survival (OS), and the clinical characteristics associated with LB positivity were determined.

RESULTS

The prevalence of EGFRT790M mutation detected using LB was 44%. In patients with negative vs. positive LB, the median OS was 45.0 months vs. 25.0 months (p= 0.0001), respectively. Patients with a T790M mutation receiving osimertinib had a median OS of 44 months (95% CI [33.05-54.99]). Clinical characteristics associated with positive LB at progression extra-thoracic involvement, > 3 metastatic sites, and bone metastases.

CONCLUSIONS

Our findings showed that LB positivity was associated with worse survival outcomes and specific clinical characteristics. This study also confirmed the feasibility and detection rate of T790M mutation in a Latin American population.

A high number of co-occurring genomic alterations detected by NGS is associated with worse clinical outcomes in advanced EGFR-mutant lung adenocarcinoma: Data from LATAM population

BACKGROUND

Co-occurring genomic alterations identified downstream main oncogenic drivers have become more evident since the introduction of next-generation sequencing (NGS) analyses at diagnosis and progression. Emerging evidence has stated that co-occurring genomic alterations at diagnosis might represent de novo and primary resistance mechanisms to tyrosine kinase inhibitors (TKIs) in advanced EGFR-mutant (EGFRm) non-small lung cancer (NSCLC). In this study, we assessed the prognostic role of co-occurring genomic alterations in advanced EGFRm NSCLC.

METHODS

A cohort of 111 patients with advanced NSCLC harboring EGFR-sensitive mutations detected by PCR was analyzed in 5 Latin American oncological centers from January 2019 to December 2020. All eligible patients received upfront therapy with EGFR-TKI. Co-occurring genomic alterations were determined at diagnosis in every patient by the NGS (FoundationOneCDx) comprehensive platform, which evaluates 324 known cancer-related genes.

RESULTS

EGFR exon19 deletion was the most frequent oncogenic driver mutation (60.4 %) detected by NGS. According to the NGS assay, 31 % and 68.3 % of patients had 1-2 and ≥ 3 co-occurring genomic alterations, respectively. The most frequent co-occurring genomic alterations were TP53 mutations (64.9 %) followed by CDKN2AB alterations (13.6 %), BRCA2 (13.6 %), and PTEN (12.7 %) mutations. Baseline central nervous system disease was present in 42.7 % of patients. First- or second-generation EGFR TKIs (gefitinib, afatinib, or erlotinib) were the most common treatment in 67.5 % of patients, while osimertinib was administered in 27.9 % of cases. The median PFS in all evaluated patients was 13.63 months (95 %CI: 11.79-15.52). Using ≥ 3 co-occurring alterations as the cut-off point, patients with ≥ 3 co-occurring genomic alterations showed a median PFS, of 12.7 months (95 %CI: 9.92-15.5) vs 21.3 months (95 %CI: 13.93-NR) in patients with 2 or less co-occurring genomic alterations [HR 3.06, (95 %CI: 1.55-5.48) p = 0.0001]. Also, patients with a TP53 mutation had a shorter PFS, 13.6 (95 %CI: 10.7-15.5) vs 19.2 months (95 %CI: 12.8-NR); in wild type TP53 [HR 2.01 (95 %CI: 1.18-3.74) p = 0.12]. In the multivariate analysis, the number (≥3) of concurrent genomic alterations and ECOG PS of 2 or more were related to a significant risk factor for progression [HR 2.79 (95 %CI: 1.49-5.23) p = 0.001 and HR 2.42 (95 %CI: 1.22-4.80) p = 0.011 respectively].

CONCLUSION

EGFR-mutant NSCLC is not a single oncogene-driven disease in the majority of cases, harboring a higher number of co-occurring genomic alterations. This study finds the number of co-occurring genomic alterations and the presence of TP53 mutations as negative prognostic biomarkers, which confers potentially earlier resistance mechanisms to target therapy.

Modifying factors of PD-L1 expression on tumor cells in advanced non-small-cell lung cancer

BACKGROUND

Programmed death ligand-1 (PD-L1) expression predicts immunotherapy utility in nononcogenic addictive lung adenocarcinoma (ADC). However, its reproducibility and reliability may be compromised outside clinical trials. This study aimed to evaluate factors associated with PD-L1 expression in lung ADC.

METHODS

This observational study assessed 547 tumor samples with advanced lung ADC from January 2016 to December 2020 in a single cancer institution. Tumor samples were stained by at least one approved PD-L1 clone, SP263 (Ventana) or 22C3 (Dako), and stratified in tumor proportion score (TPS) <1%, 1-49%, or ≥50%.

RESULTS

Of all the tumor samples, positive PD-L1 staining was higher in poorly differentiated tumors (67.3% vs. 32.7%, p < 0.001). Analytical factors associated with a PD-L1 high expression (TPS ≥ 50%) were the SP263 clone (19.6% vs. 8.2%, p < 0.001), time of archival tumor tissue <12 months (15.3% vs. 3.8%, p = 0.024), whenever the analysis was performed in the most recent years (2019-2020) (19.0% vs. 8.3%, p < 0.001), and whenever the analysis was performed by pathologists in the academic setting (Instituto Nacional de Cancerologia, INCan) (19.9% vs. 11.9%, p = 0.001). In the molecular analysis, EGFR wild-type tumors had an increased proportion of PD-L1 positive and PD-L1 high cases (60.2% vs. 47.9%, p = 0.006 and 17.4% vs.8.5%, p = 0.004). A moderate correlation (r = 0.69) in the PD-L1 TPS% was observed between the two different settings (INCan vs. external laboratories).

CONCLUSION

Clinicopathological factors were associated with an increased PD-L1 positivity rate. These differences were significant in the PD-L1 high group and associated with the academic setting, the SPS263 clone, time of archival tumor tissue <12 months, and a more recent period in the PD-L1 analysis.

Clinical Impact of the COVID-19 Pandemic in Mexican Patients with Thoracic Malignancies

BACKGROUND

Accumulated evidence indicates that patients with lung cancer are a vulnerable population throughout the pandemic. Limited information is available in Latin America regarding the impact of the pandemic on medical care. The goal of this study was to describe the clinical and social effect of COVID-19 on patients with thoracic cancer and to ascertain outcomes in those with a confirmed diagnosis.

MATERIALS AND METHODS

This cohort study included patients with thoracic neoplasms within a single institution between March 1, 2020, and February 28, 2021. All variables of interest were extracted from electronic medical records. During this period, the Depression Anxiety and Stress Scale 21 (DASS-2) was applied to evaluate and identify more common psychological disorders.

RESULTS

The mean age for the total cohort (n = 548) was 61.5 ± 12.9 years; non-small cell lung cancer was the most frequent neoplasm (86.9%), advanced stages predominated (80%), and most patients were under active therapy (82.8%). Any change in treatment was reported in 23.9% of patients, of which 78.6% were due to the COVID-19 pandemic. Treatment delays (≥7 days) were the most frequent modifications in 41.9% of cases, followed by treatment suspension at 37.4%. Patients without treatment changes had a more prolonged progression-free survival and overall survival (hazard ratio [HR] 0.21, p < .001 and HR 0.28, p < .001, respectively). The mean DASS-21 score was 10.45 in 144 evaluated patients, with women being more affected than men (11.41 vs. 9.08, p < .001). Anxiety was reported in 30.5% of cases, followed by depression and distress in equal proportions (18%). Depressed and stressed patients had higher odds of experiencing delays in treatment than patients without depression (odds ratio [OR] 4.5, 95% confidence interval [CI] 1.53-13.23, p = .006 and OR 3.18, 95% CI 1.2-10.06, p = .006, respectively).

CONCLUSION

Treatment adjustments in patients with thoracic malignancies often occurred to avoid COVID-19 contagion with detrimental effects on survival. Psychological disorders could have a role in adherence to the original treatment regimen.

IMPLICATIONS FOR PRACTICE

The pandemic has placed an enormous strain on health care systems globally. Patients with thoracic cancers represent a vulnerable population, with increased morbidity and mortality rates. In Mexico, treatment modifications were common during the pandemic, and those who experienced delays had worse survival outcomes. Most treatment modifications were related to a patient decision rather than a lockdown of health care facilities in which mental health impairment plays an essential role. Moreover, the high case fatality rate highlights the importance of improving medical care access. Likewise, to develop strategies facing future threats that may compromise health care systems in non-developed countries.

Impact of detecting plasma EGFR mutations with ultrasensitive liquid biopsy in outcomes of NSCLC patients treated with first- or second-generation EGFR-TKIs

BACKGROUND

Few trials have evaluated the utility of liquid biopsies to detect epidermal growth factor receptor mutations (EGFRm) at the time of response evaluation and its association with the clinical characteristics and outcomes of non-small-cell lung cancer (NSCLC) patients.

OBJECTIVE

This study aimed to evaluate, in a real-world clinical setting, the prevalence of plasma EGFRm and its association with the clinical characteristics, response and survival outcomes of NSCLC patients under treatment with EGFR-tyrosine kinase inhibitors (EGFR-TKIs).

METHODS

This observational study enrolled advanced or metastatic NSCLC patients, with confirmed tumor EGFRm, receiving treatment with first- or second-generation EGFR-TKIs. Blood samples for the detection of plasma EGFRm were collected at the time of response evaluation and processed using the Target Selector™ assay. The main outcomes were the detection rate of plasma EGFRm, median Progression-Free Survival (PFS) and Overall Survival (OS) according to plasma EGFR mutational status.

RESULTS

Of 84 patients, 50 (59.5%) had an EGFRm detected in plasma. After a median follow-up of 21.1 months, 63 patients (75%) had disease progression. The detection rate of plasma EGFRm was significantly higher in patients with disease progression than in patients with partial response or stable disease (68.3% versus 33.3%; P< 0.01). PFS and OS were significantly longer in patients without plasma EGFRm than among patients with plasma EGFRm (14.3 months [95% CI, 9.25-19.39] vs 11.0 months [95% CI, 8.61-13.46]; P= 0.034) and (67.8 months [95% CI, 39.80-95.94] vs 32.0 months [95% CI, 17.12-46.93]; P= 0.006), respectively. A positive finding in LB was associated with the presence of ⩾ 3 more metastatic sites (P= 0.028), elevated serum carcinoembryonic (CEA) at disease progression (P= 0.015), and an increase in CEA with respect to baseline levels (P= 0.038).

CONCLUSIONS

In NSCLC patients receiving EGFR-TKIs, the detection of plasma EGFRm at the time of tumor response evaluation is associated with poor clinical outcomes.

Brigatinib in ALK-positive non-small cell lung cancer: real-world data in the Latin American population (Bri-world extend CLICaP)

Background: Brigatinib has demonstrated its efficacy as first-line therapy and in further lines for ALK-positive non-small cell lung cancer (NSCLC) patients; however, real-world data in Latin America are scarce. Methods: From January 2018 to March 2020, 46 patients with advanced ALK-positive NSCLC received brigatinib as second or further line of therapy in Mexico and Colombia. The primary end point was progression-free survival (PFS); secondary end point was time to treatment discontinuation (TTD). Results: At a median follow-up of 9.3 months, the median PFS was 15.2 months (95% CI: 11.6-18.8), and TTD was 18.46 months (95% CI: 9.54-27.38). The estimated overall survival at 12 months was 80%. Safety profile was consistent with previously published data. Conclusion: Brigatinib is an effective treatment for previously treated ALK-positive NSCLC patients in a real-world setting.

Recommendations for detection, prioritization, and treatment of thoracic oncology patients during the COVID-19 pandemic: the THOCOoP cooperative group

The world currently faces a pandemic due to SARS-CoV-2. Relevant information has emerged regarding the higher risk of poor outcomes in lung cancer patients. As such, lung cancer patients must be prioritized in terms of prevention, detection and treatment. On May 7th, 45 experts in thoracic cancers from 11 different countries were invited to participate. A core panel of experts regarding thoracic oncology care amidst the pandemic gathered virtually, and a total of 60 initial recommendations were drafted based on available evidence, 2 questions were deleted due to conflicting evidence. By May 16th, 44 experts had agreed to participate, and voted on each of the 58 recommendation using a Delphi panel on a live voting event. Consensus was reached regarding the recommendations (>66 % strongly agree/agree) for 56 questions. Strong consensus (>80 % strongly agree/agree) was reached for 44 questions. Patients with lung cancer represent a particularly vulnerable population during this time. Special care must be taken to maintain treatment while avoiding exposure.

Toward early diagnosis of lung cancer

Our long term research goal is to develop a fully automated, image-based diagnostic system for early diagnosis of pulmonary nodules that may lead to lung cancer. In this paper, we focus on generating new probabilistic models for the estimated growth rate of the detected lung nodules from Low Dose Computed Tomography (LDCT). We propose a new methodology for 3D LDCT data registration which is non-rigid and involves two steps: (i) global target-to-prototype alignment of one scan to another using the learned prior appearance model followed by (ii) local alignment in order to correct for intricate relative deformations. Visual appearance of these chest images is described using a Markov-Gibbs random field (MGRF) model with multiple pairwise interaction. An affine transformation that globally registers a target to a prototype is estimated by the gradient ascent-based maximization of a special Gibbs energy function. To handle local deformations, we displace each voxel of the target over evolving closed equi-spaced surfaces (iso-surfaces) to closely match the prototype. The evolution of the iso-surfaces is guided by a speed function in the directions that minimize distances between the corresponding voxel pairs on the iso-surfaces in both the data sets. Preliminary results show that the proposed accurate registration could lead to precise diagnosis and identification of the development of the detected pulmonary nodules.

A novel 3D joint Markov-Gibbs model for extracting blood vessels from PC-MRA images

New techniques for more accurate segmentation of a 3D cerebrovascular system from phase contrast (PC) magnetic resonance angiography (MRA) data are proposed. In this paper, we describe PC-MRA images and desired maps of regions by a joint Markov-Gibbs random field model (MGRF) of independent image signals and interdependent region labels but focus on most accurate model identification. To better specify region borders, each empirical distribution of signals is precisely approximated by a Linear Combination of Discrete Gaussians (LCDG) with positive and negative components. We modified the conventional Expectation-Maximization (EM) algorithm to deal with the LCDG. The initial segmentation based on the LCDG-models is then iteratively refined using a MGRF model with analytically estimated potentials. Experiments with both the phantoms and real data sets confirm high accuracy of the proposed approach.

Paradoxical embolism and aortic occlusion: a case report

This is the case report of a 45-year-old woman who sustained a left popliteal artery embolism. Ten days after popliteal embolectomy, she developed sudden occlusion of the distal aorta. She required a bifemoral embolectomy. Transesophageal echocardiogram demonstrated an atrial septal aneurysm and a septal defect with a right to left shunt. A venogram showed deep venous thrombosis in the right leg as the potential source of the embolism. Paradoxical embolization should be considered when ever an unexplained arterial occlusion occurs, especially in younger patients.

Lactitol vs. lactulose in the treatment of chronic recurrent portal-systemic encephalopathy

To compare the efficacy and patient acceptability of lactitol vs. lactulose in chronic recurrent portal-systemic encephalopathy (PSE), 25 cirrhotic patients with a history of repeated episodes of hepatic encephalopathy who required chronic administration of lactulose were included in a controlled cross-over clinical trial in which patients received, at random, lactitol (at an initial dosage of 10 g/6 h) or lactulose (15 ml/6 h, 66% w/v, containing 10 g of lactulose) during a 3 month period and then crossed-over to the alternative treatment for the following 3 months. Doses were adjusted to obtain two bowel movements per day. During the study period the daily protein intake was 40-60 g. Clinical and analytical data (including ammonia levels) were obtained, an EEG and the number connection test were performed and the PSE index was determined before treatment and monthly until the end of the treatment. No significant differences were found between the effects of lactitol and lactulose on the neurological and biological parameters, suggesting that the two treatments could be considered as equally effective. Lactitol was significantly better tolerated than lactulose (P = 0.02), the taste of which was assessed as being too sweet and provoking nausea. In conclusion, lactitol is a good alternative to lactulose for patients with chronic recurrent PSE, especially in those who do not tolerate the excessive sweetness of lactulose.

Cyanamide hepatotoxicity. Incidence and clinico-pathological features

Ground-glass hepatocytes resembling those seen in HBsAg carriers on hematoxylin and eosin and on trichrome stained sections, but giving a negative reaction to orcein and a positive one to PAS, were found in liver biopsy specimens from nine asymptomatic former alcoholics who were on treatment with cyanamide, in one of four who had been treated with cyanamide several months before the liver biopsy procedure, in none of 15 treated with disulfiram, and in one of eight who had apparently not received aversive drugs. Portal and periportal inflammatory changes and fibrosis were more frequently observed in biopsy specimens containing PAS-positive ground-glass hepatocytes than in those without, but cirrhosis was found with a similar frequency. It is concluded that periportal PAS-positive ground-glass hepatocytes are a histological marker of cyanamide treatment.

Lactitol versus lactulose in the treatment of acute portal systemic encephalopathy (PSE). A controlled trial

Preliminary data suggest that lactitol (beta-galactoside-sorbitol), a new synthetic non-absorbable disaccharide, has beneficial effects on chronic portal systemic encephalopathy. To compare the efficacy of lactitol vs. lactulose in the treatment of acute portal systemic encephalopathy (PSE), 40 cirrhotic patients with an acute episode of PSE were randomly allocated to one of two groups: group A (20 patients) received lactulose (30 ml/6 h) and group B (20 patients) lactitol (12 g/6 h). These doses were adjusted daily to obtain two bowel movements per day. The duration of treatment was 5 days. Age, sex, hepatic and renal function, precipitating factors and level of PSE measured by clinical examination, EEG and number connection test were similar in the two groups. A complete clinical resolution of PSE occurred in 11 patients in each group. In 5 patients of the lactulose group and in 6 of the lactitol group there was a moderate improvement of PSE during the study. Finally, 4 patients in the lactulose group and 3 in the lactitol group did not respond to treatment. No side effects attributable to therapy were observed in either group. These results indicate that lactitol is as effective as lactulose in the management of patients with cirrhosis and acute PSE.

Serum procollagen type III peptide as a marker of hepatic fibrogenesis in alcoholic hepatitis

To evaluate if serum procollagen type III peptide levels reflect the extent of liver fibrosis and hepatic collagen synthesis, we have studied 19 patients with histologically proven alcoholic hepatitis and 9 chronic alcoholics with normal liver histology or minimal steatosis. Serum procollagen peptide type III was measured at the time of liver biopsy, and determination of hepatic prolyl-hydroxylase activity, as an index of collagen synthesis, was performed in all liver samples. Hepatic prolyl-hydroxylase activity and serum procollagen peptide levels were significantly higher in patients with alcoholic hepatitis (959 +/- 115 cpm/mg and 33.2 +/- 5.3 ng/ml, respectively) than in alcoholics from the control group (537 +/- 62 cpm/mg and 10.9 +/- 1.5 ng/ml, respectively) (p less than 0.05 and p less than 0.01, respectively). All patients with alcoholic hepatitis had fibrosis (10 mild and 9 severe). Prolyl-hydroxylase activity and procollagen peptide levels were significantly higher in alcoholic hepatitis patients with severe fibrosis than in those with mild fibrosis (1208 +/- 154 cpm/mg vs. 734 +/- 138 cpm/mg, p less than 0.05 and 49.1 +/- 8.8 ng/ml vs. 20.4 +/- 2.6 ng/ml, p less than 0.01). Furthermore, a close correlation was found between the hepatic prolyl-hydroxylase activity and the serum level of procollagen peptide (r = 0.76, p less than 0.001). We conclude that the serum procollagen peptide level is a good marker of hepatic fibrogenesis in alcoholic hepatitis; thus, its serial measurement could be useful in identifying patients in progress to cirrhosis and in assessing the therapeutic efficiency of antifibrogenic drugs.

Measurement of fibrosis in needle liver biopsies: evaluation of a colorimetric method

Collagen content was measured in 38 needle liver biopsies (8 steatosis, 8 chronic hepatitis, 7 fibrosis and 15 cirrhosis) by a new colorimetric method based on the selective capacity of Sirius red and Fast green to bind to collagen and noncollagenous proteins, respectively. The values were compared with those obtained after determination of the degree of fibrosis by morphometry in the same tissue. In biopsies with cirrhosis and fibrosis, there was a higher amount of collagen than in biopsies with chronic hepatitis and steatosis. Furthermore, there was a highly significant direct correlation between the collagen content measured colorimetrically and the degree of fibrosis determined morphometrically (r = 0.77, p less than 0.001), suggesting that this new colorimetric method is useful in measuring the degree of fibrosis in needle liver biopsies.

[Alterations of systolic and electrocardiographic time intervals in normal patients by Ro 11-1781, a new calcium-antagonist (author's transl)]

Five minutes following intravenous application of calcium antagonist Ro 11-1781 (1 mg/kg BDW) PQ duration increased significantly in 10 healthy volunteers without more severe atrioventricular conduction disturbances. Both, systolic and diastolic blood pressure decreased and heart rate increased significantly. Left ventricular ejection time (LVET) and the time from the beginning of QRS to the first sound (QS1) did not change in contrast to a significant decrease of the electromechanical systolic interval (QS2) and of the total pre-ejection-period (PEP). The decrease in PEP is explained by a decrease in isovolumic contraction time (IVCT). This can be regarded in connection with a decreased PEP/LVET-ratio, an expression of better heart performance. In spite of the negative inotropic effect of the calcium antagonist Ro 11-1781, our results point to an increase in left ventricular performance and in heart rate caused by an exaggerated sympathic reaction to a fall in blood pressure.