MET alterations as resistance mechanisms of dabrafenib-trametinib in BRAF p.V600E mutated non-small cell lung cancer patient.

The combination of BRAF and MEK inhibitors demonstrated significant clinical benefit in patients with BRAF-mutant non-small cell lung cancer (NSCLC). However, the molecular mechanisms of acquired resistance to BRAF and MEK inhibition in NSCLC are still unknown. Herein, we report a case of a 76-year-old man with a history of smoking who was diagnosed with BRAF V600E-mutant lung adenocarcinoma (PD-L1 > 50%) and subsequently candidate to first-line therapy with pembrolizumab. After 18 months since the start of immunotherapy, computed tomography scan showed disease progression and a second-line therapy with dabrafenib and trametinib was initiated. Seven months later, due to a suspect disease progression, a left supraclavicular lymphadenectomy was performed and next-generation sequencing analysis revealed the appearance of MET exon 14 skipping mutation, while fluorescence in situ hybridization analysis showed MET amplification. The patient is still on BRAF and MEK inhibitor treatment. Our case highlights the relevance of performing tumor tissue rebiopsy at the time of progression during treatment with BRAF/MEK inhibition with the aim of identifying putative mechanisms of resistance.

Is Lobectomy Actually Worse Than Segmentectomy for All Stage I Non-Small Cell Lung Cancer?

INTRODUCTION: The recent results of the JCOG 0802 and CALGB 140503 studies suggest that segmentectomy should be considered instead of lobectomy for patients with peripheral <2 cm node-negative non-small cell lung cancer (NSCLC). This study aimed to test this hypothesis in a retrospective analysis of a larger dataset of patients with stage I NSCLC recorded in the Surveillance, Epidemiology, and End Results database. METHODS: Patients with all stage I NSCLC (≤4 cm in size) who underwent either segmentectomy or lobectomy from 2000 to 2017 were analyzed. The primary endpoints were overall survival and lung cancer-specific survival, while the secondary endpoints were the 30-day and 90-day mortality. RESULTS: Overall, 32,673 patients treated by lobectomy and 2166 patients treated by segmentectomy were included in the initial data collection. After 1:1 propensity score matching (PSM), 2016 patients in each group were enrolled in the final analysis with well-balanced baseline characteristics. After PSM, there was no difference between segmentectomy and lobectomy for all stage IA NSCLC (≤3 cm in size) in both overall survival and lung cancer-specific survival (hazard ratio: 0.87 [0.74-1.02], P value: 0.09 and hazard ratio: 0.81 [0.4-1.03], P value: 0.09, respectively). Furthermore, lobectomy had higher 30-day mortality than segmentectomy: 1.1% versus 2.1%, P value: 0.01. However, this difference was not significant for 90-day mortality, even after PSM (3.9% versus 3.0%, P value: 0.17). CONCLUSIONS: We found no evidence to support the use of lobectomy rather than segmentectomy in stage IA NSCLC in terms of either overall or lung cancer-specific long-term survival. The choice of lobectomy may also be detrimental to early postoperative recovery.

CD26 Is Differentially Expressed throughout the Life Cycle of Infantile Hemangiomas and Characterizes the Proliferative Phase.

Infantile hemangiomas (IHs) are benign vascular neoplasms of childhood (prevalence 5-10%) due to the abnormal proliferation of endothelial cells. IHs are characterized by a peculiar natural life cycle enclosing three phases: proliferative (≤12 months), involuting (≥13 months), and involuted (up to 4-7 years). The mechanisms underlying this neoplastic disease still remain uncovered. Twenty-seven IH tissue specimens (15 proliferative and 12 involuting) were subjected to hematoxylin and eosin staining and a panel of diagnostic markers by immunohistochemistry. WT1, nestin, CD133, and CD26 were also analyzed. Moreover, CD31pos/CD26pos proliferative hemangioma-derived endothelial cells (Hem-ECs) were freshly isolated, exposed to vildagliptin (a DPP-IV/CD26 inhibitor), and tested for cell survival and proliferation by MTT assay, FACS analysis, and Western blot assay. All IHs displayed positive CD31, GLUT1, WT1, and nestin immunostaining but were negative for D2-40. Increased endothelial cell proliferation in IH samples was documented by ki67 labeling. All endothelia of proliferative IHs were positive for CD26 (100%), while only 10 expressed CD133 (66.6%). Surprisingly, seven involuting IH samples (58.3%) exhibited coexisting proliferative and involuting aspects in the same hemangiomatous lesion. Importantly, proliferative areas were characterized by CD26 immunolabeling, at variance from involuting sites that were always CD26 negative. Finally, in vitro DPP-IV pharmacological inhibition by vildagliptin significantly reduced Hem-ECs proliferation through the modulation of ki67 and induced cell cycle arrest associated with the upregulation of p21 protein expression. Taken together, our findings suggest that CD26 might represent a reliable biomarker to detect proliferative sites and unveil non-regressive IHs after a 12-month life cycle.

Testicular metastasis of prostate adenocarcinoma: the other side of orchiepididymitis.

Background: Metastatic prostate adenocarcinoma is a rare event and there are few references to this topic. We report an unusual case of prostate cancer metastasis and review of contemporary literature. Moreover, we discuss the pathogenesis and the clinical aspects of this event. Case presentation: A 70-year-old patient was admitted to the hospital for right scrotal pain. The ultrasound examination described an increase in testicular size, suggesting the possibility of orchiepididymitis. Past medical history reported a previous prostate adenocarcinoma. Inflammatory blood tests were normal. Importantly, PSA was 3.3 ng/ml. PET scan positivity in the scrotum raised suspicion of a relapse. Therefore, he underwent right orchiectomy. Conclusion: Although metastatic prostate adenocarcinoma is rare, a correct diagnosis is of paramount importance because the therapy changes accordingly. Patients who complain of scrotal pain need to be examined accurately. Although the most common cause behind this symptom is infectious, the patient's past medical history should be reviewed to exclude previous malignancies.

Impact of High-Grade Patterns in Early-Stage Lung Adenocarcinoma: A Multicentric Analysis.

OBJECTIVE: The presence of micropapillary and solid adenocarcinoma patterns leads to a worse survival and a significantly higher tendency to recur. This study aims to assess the impact of pT descriptor combined with the presence of high-grade components on long-term outcomes in early-stage lung adenocarcinomas. METHODS: We retrospectively collected data of consecutive resected pT1-T3N0 lung adenocarcinoma from nine European Thoracic Centers. All patients who underwent a radical resection with lymph-node dissection between 2014 and 2017 were included. Differences in Overall Survival (OS) and Disease-Free Survival (DFS) and possible prognostic factors associated with outcomes were evaluated also after performing a propensity score matching to compare tumors containing non-high-grade and high-grade patterns. RESULTS: Among 607 patients, the majority were male and received a lobectomy. At least one high-grade histological pattern was seen in 230 cases (37.9%), of which 169 solid and 75 micropapillary. T1a-b-c without high-grade pattern had a significant better prognosis compared to T1a-b-c with high-grade pattern (p = 0.020), but the latter had similar OS compared to T2a (p = 0.277). Concurrently, T1a-b-c without micropapillary or solid patterns had a significantly better DFS compared to those with high-grade patterns (p = 0.034), and it was similar to T2a (p = 0.839). Multivariable analysis confirms the role of T descriptor according to high-grade pattern both for OS (p = 0.024; HR 1.285 95% CI 1.033-1.599) and DFS (p = 0.003; HR 1.196, 95% CI 1.054-1.344, respectively). These results were confirmed after the propensity score matching analysis. CONCLUSIONS: pT1 lung adenocarcinomas with a high-grade component have similar prognosis of pT2a tumors.

KRAS: A Druggable Target in Colon Cancer Patients.

Mutations in KRAS are among the most frequent aberrations in cancer, including colon cancer. KRAS direct targeting is daunting due to KRAS protein resistance to small molecule inhibition. Moreover, its elevated affinity to cellular guanosine triphosphate (GTP) has made the design of specific drugs challenging. Indeed, KRAS was considered 'undruggable'. KRASG12C is the most commonly mutated variant of KRAS in non-small cell lung cancer. Currently, the achievements obtained with covalent inhibitors of this variant have given the possibility to assess the best therapeutic approach to KRAS-driven tumors. Mutation-related biochemical assets and the tissue of origin are expected to influence responses to treatment. Further attempts to obtain mutant-specific KRAS (KRASG12C) switch-II covalent inhibitors are ongoing and the results are promising. Drugs targeted to block KRAS effector pathways could be combined with direct KRAS inhibitors, immunotherapy or T cell-targeting approaches in KRAS-mutant tumors. The development of valuable combination regimens will be essential against potential mechanisms of resistance that may arise during treatment.

Afatinib therapy in case of EGFR G724S emergence as resistance mechanism to osimertinib.

Osimertinib is a third-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) used both as the first-line treatment of EGFR-mutated non-small cell lung cancer patients and in second-line after T790M-positive disease progression to first- or second-generation TKIs. Unfortunately, patients unavoidably experience disease progression to osimertinib and the current research is focused on resistance mechanisms and the relative therapeutic strategy. We report the case of a patient with advanced EGFR-mutated (exon 19 deletion and T790M-positive) non-small cell lung cancer who developed disease progression to osimertinib characterized by the loss of T790M concurrently with the emergence of G724S EGFR mutation, which was tackled by subsequent afatinib treatment. Next-generation sequencing molecular study of rebiopsy at time of progression to osimertinib revealed the persistence of EGFR exon 19 deletion, loss of T790M with a new G724S EGFR mutation; other concomitant mechanisms were excluded. Retrospective analysis of cell-free DNA revealed the emergence of G724S EGFR mutation four months before the radiologically-proven disease progression. The patient, after chemotherapy, was treated with afatinib with clinical and radiological benefit. Our case report contributes to increase the knowledge on acquired resistance mechanisms to osimertinib treatment, and it shows, for the first time, the efficacy of afatinib in the case of T790M loss and emergence of G724S EGFR mutation.

Prognostic impact of lung adenocarcinoma second predominant pattern from a large European database.

BACKGROUND AND OBJECTIVES: Adenocarcinoma patterns could be grouped based on clinical behaviors: low- (lepidic), intermediate- (papillary or acinar), and high-grade (micropapillary and solid). We analyzed the impact of the second predominant pattern (SPP) on disease-free survival (DFS). METHODS: We retrospectively collected data of surgically resected stage I and II adenocarcinoma. SELECTION CRITERIA: anatomical resection with lymphadenectomy and pathological N0. Pure adenocarcinomas and mucinous subtypes were excluded. Recurrence rate and factors affecting DFS were analyzed according to the SPP focusing on intermediate-grade predominant pattern adenocarcinomas. RESULTS: Among 270 patients, 55% were male. The mean age was 68.3 years. SPP pattern appeared as follows: lepidic 43.0%, papillary 23.0%, solid 14.4%, acinar 11.9%, and micropapillary 7.8%. The recurrence rate was 21.5% and 5-year DFS was 71.1%. No difference in DFS was found according to SPP (p = .522). In patients with high-grade SPP, the percentage of SPP, age, and tumor size significantly influenced DFS (p = .016). In patients with lepidic SPP, size, male gender, and lymph-node sampling (p = .005; p = .014; p = .038, respectively) significantly influenced DFS. CONCLUSIONS: The impact of SPP on DFS is not homogeneous in a subset of patients with the intermediate-grade predominant patterns. The influence of high-grade SPP on DFS is related to its proportion in the tumor.

The role of miRNA-221 and miRNA-126 in patients with benign metastasizing leiomyoma of the lung: an overview with new interesting scenarios.

Benign metastasizing leiomyoma (BML) is a rare disease characterized by extrauterine benign leiomyomatosis in patients with a previous or concomitant history of uterine leiomyoma. Currently, there are no specific criteria to predict the metastasizing ability of the uterine leiomyoma and the risk of malignant degeneration of pulmonary BML, and these are the aims of this study. We analyzed 10 uterine (three leiomyomas, four leiomyomas that gave rise to lung BML, three healthy tissues) and 11 pulmonary tissue samples (eight lung BML, three healthy tissues). Interestingly, one of the BML lesions exceptionally evolved into a leiomyosarcoma (case 2). Uterine leiomyoma microvascular density (MVD) was higher in the patients with uterine leiomyomas that gave rise to lung BML, reaching a peak in case 2. Strong positivity for the estrogen (ER) and progesterone (PR) receptors and a low proliferation index (Ki67 < 1%) were discovered both in patients with uterine leiomyoma and in patients with BML. Interestingly, in case 2, the last dedifferentiated leiomyosarcoma showed a weaker ER and PR positivity with a higher proliferation index (Ki67:30%). Regarding the uterine miRNA-126, a trend toward a hypo-expression between uterine leiomyoma and uterine leiomyoma that gave rise to lung BML was discovered, reaching the lowest level in case 2. Considering the pulmonary samples, we observed a higher miRNA-221 and a lower miRNA-126 expression in the leiomyosarcoma. We tried to better elucidate the biological behaviour of this rare disease. The analysis of the miRNA-221 and miRNA-126 could offer new diagnostic, prognostic and therapeutic perspectives.

Sorafenib and hepatocellular carcinoma: is alpha-fetoprotein a biomarker predictive of tumor biology and primary resistance?

Background: Alpha-fetoprotein (AFP) is the only biomarker with proven prognostic value in advanced hepatocellular carcinoma. Preliminary data indicate crosstalk between AFP and VEGF signaling. Methods: The authors looked at 69 patients with advanced hepatocellular carcinoma who were previously tested for VEGFR2 expression, had available baseline AFP serum concentrations and were treated with sorafenib within clinical trials. Results: Shorter progression-free survival and overall survival were associated with increased AFP level and elevated VEGFR2 staining. At multivariate analysis of AFP level was the only independent prognostic factor for progression-free survival and overall survival. Conclusion: The authors' study confirms the adverse prognostic role of elevated baseline AFP and also suggests a possible role of AFP in primary resistance to sorafenib therapy.

Lay abstract Alpha-fetoprotein (AFP) is a plasma protein commonly used as a tumor marker for hepatocellular carcinoma. Sorafenib is a targeted therapy used to block the growth of cancer cells in several ways. It affects various proteins on the surface of cancer cells as well as targets inside the cell. Some of these targets are involved in tumor angiogenesis (growth of new blood vessels). In the present analysis, elevated AFP plasma levels before starting sorafenib therapy were correlated with inferior survival compared with patients with low AFP levels, thus suggesting a possible role of AFP in resistance to sorafenib therapy. Using a specific antibody, the authors also studied the expression on cancer cells of VEGFR2, which is a protein involved in angiogenesis and one of the targets of sorafenib. No correlation was found between AFP level and VEGFR2 expression. The underlying mechanisms involved in resistance to sorafenib therapy still need to be clarified and deserve further studies.

Modulating Tumor Microenvironment: A Review on STK11 Immune Properties and Predictive vs Prognostic Role for Non-small-cell Lung Cancer Immunotherapy.

OPINION STATEMENT: The quest for immunotherapy (IT) biomarkers is an element of highest clinical interest in both solid and hematologic tumors. In non-small-cell lung cancer (NSCLC) patients, besides PD-L1 expression evaluation with its intrinsic limitations, tissue and circulating parameters, likely portraying the tumor and its stromal/immune counterparts, have been proposed as potential predictors of IT responsiveness. STK11 mutations have been globally labeled as markers of IT resistance. After a thorough literature review, STK11 mutations condition the prognosis of NSCLC patients receiving ICI-containing regimens, implying a relevant biological and clinical significance. On the other hand, waiting for prospective and solid data, the putative negative predictive value of STK11 inactivation towards IT is sustained by less evidence. The physiologic regulation of multiple cellular pathways performed by STK11 likely explains the multifaceted modifications in tumor cells, stroma, and tumor immune microenvironment (TIME) observed in STK11 mutant lung cancer, particularly explored in the molecular subgroup of KRAS co-mutation. IT approaches available thus far in NSCLC, mainly represented by anti-PD-1/PD-L1 inhibitors, are not promising in the case of STK11 inactivation. Perceptive strategies aimed at modulating the TIME, regardless of STK11 status or specifically addressed to STK11-mutated cases, will hopefully provide valid therapeutic options to be adopted in the clinical practice.

Sarcoid-like reaction mimicking disease progression in an ALK-positive lung cancer patient receiving lorlatinib.

The administration of target inhibitors is paramount to grant the longest survival in patients with ALK-positive non-small cell lung cancer (NSCLC). The eventual resistance to tyrosine kinase inhibitors (TKI) is monitored clinically and radiologically for prompt molecule shift to further generation TKI, if available. However, the early radiological detection of progression pattern (e.g. nodule onset) should be regarded with caution because overlaps exist with non-tumor cell proliferation and/or accumulation. Here we report the case of a stage IV ALK-rearranged NSCLC patient exposed to serial crizotinib, brigatinib, ceritinib, and lorlatinib (this latter brought to complete brain and leptomeningeal disease response), in a period of more than five years. During lorlatinib, the appearance of solid pulmonary nodules was obviously interpreted as disease progression. However, surgical biopsies of the pulmonary nodules revealed features of sarcoid-like granulomatous lymphadenitis, namely without tumor cell. This invasive approach, besides documenting for the first time a sarcoid-like reaction to ALK inhibitors, allowed to revert the radiological diagnosis and maintain lorlatinib, for the best patient outcome. The pragmatic relevance of these findings suggests a careful attitude towards the interpretation of radiologic patterns of disease progression in patients under TKI.

Plasma exchange-sensitive syncytial glomerulopathy in a kidney transplant patient.

Microvascular inflammation (MVI), defined as the presence of glomerulitis and/or peritubular capillaritis, is the key histological lesion of anti-HLA donor-specific antibodies (DSA)-related antibody mediated rejection, but recently other possible mechanisms of MVI have emerged. However, except for peritubular capillary C4d deposition that is more frequently observed in the presence of anti-HLA-DSA, histological features are similar regardless of MVI origin. Therefore, accurately describing patterns of MVI may help differentiate etiologies and drive therapeutic choices. We describe the case of a kidney transplant recipient (primary nephropathy: autosomal dominant polycystic kidney disease) who underwent kidney biopsy for worsening renal function and new onset hypertension. Histologic findings showed severe microvascular inflammation with intense glomerulitis and presence of intracapillary multinucleated cells, positive on immunostaining for endothelial marker ETS-related gene (ERG). Focal intense peritubular capillaritis and early glomerular basement membrane reduplication, C4d negative, were observed, consistent with early chronic active ABMR. HLA-DSA were absent, but high level of anti-angiotensin II type-1 receptor (AT1R) antibodies (Ab) were detected (78 U/L, normal levels < 10 U/L). Two subsequent biopsies showed intense microvascular inflammation with diffuse peritubular capillaritis, and multinucleated, ERG-positive, endothelial cells were still seen in glomerular capillary loops. The patient was started on angiotensin receptor blockers (ARBs) and plasma exchange (PEX) sessions obtaining normalization of blood pressure and AT1R Ab and proteinuria reduction, but, after subsequent liver transplant, rituximab therapy failed to maintain remission and the patient remained PEX-dependent.

Immunomodulatory effects of antiangiogenic tyrosine kinase inhibitors in renal cell carcinoma models: Impact on following anti-PD-1 treatments.

The approval of immune checkpoint inhibitors (ICIs) has revolutionized the management of metastatic renal cell carcinoma (RCC), introducing several ICI-based combinations as the new standard of care for affected patients. Nonetheless, monotherapy with antiangiogenic tyrosine kinase inhibitors (TKIs), such as pazopanib or sunitinib, still represents a first-line treatment option for selected patients belonging to the favorable risk group according to the International mRCC Database Consortium (IMDC) model. After TKI monotherapy, the main second-line option is represented by ICI monotherapy with the anti-Programmed Death Receptor 1(PD-1) nivolumab. To date, the expected clinical outcomes are similar with pazopanib or sunitinib and there is no clear indication for selecting one TKI over the other. Moreover, their impact on subsequent ICI treatment outcomes is not well defined, yet. Based on these premises, we investigated the immunomodulatory activity of these drugs in vitro and in vivo.Both TKIs induced Programmed Cell Death Ligand-1 (PD-L1) expression and soluble PD-L1 release in RCC cells, and hampered T cell activation, reducing cytokine production and the proportion of activated T cells. Nevertheless, in a syngeneic co-culture system with peripheral blood mononuclear cells (PBMCs) and tumor cells, incubation with anti-PD-1 antibody following TKIs treatment significantly restored T cell function, potentiating the cytotoxic effects against tumor cells. Pazopanib and sunitinib followed by anti-PD-1 antibody produced a comparable inhibition of tumor growth in a RCC syngeneic mouse model. Our findings suggest that pazopanib and sunitinib, showing similar immunomodulatory effects, may have a comparable impact on the subsequent effectiveness of PD-1/PD-L1 blockade.

Intersecting Blood Cytokines With Cholesterol Parameters to Profile Patients With Advanced Solid Tumors Receiving Immune Checkpoint Inhibitors.

The study investigated the relationship between serum proinflammatory cytokine levels, cholesterol metabolism, and clinical outcome in cancer patients undergoing immune checkpoint inhibitors (ICIs). Peripheral blood was collected before therapy from ICI-treated advanced cancer patients. We retrospectively assessed plasma total cholesterol (TC), ABCA1- and ABCG1-mediated cholesterol efflux (CE), passive diffusion (PD), cholesterol loading capacity (CLC), and serum IL-6, IL-10, and TNF-α. The association between blood cholesterol parameters and inflammatory cytokines and their effect on overall survival (OS), progression-free survival (PFS), and clinical benefit (CB) from ICIs were statistically assessed. Among 70 consecutively enrolled patients (nonsmall cell lung cancer: 94%; renal cell carcinoma: 6%), TC, CLC, and cholesterol PD resulted significantly higher in IL-6 low and IL-10 low cases ( P <0.05), whereas ABCA1-mediated CE was increased in IL-10 high patients ( P =0.018). Uni- and multivariable analysis revealed meaningfully longer OS and PFS in IL-6 low (HR 2.13 and 2.97, respectively) and IL-10 low (HR 3.17 and 2.62) groups. At univariate analysis all cholesterol-related indices significantly correlated with OS and PFS, whereas at multivariate only high PD was validated as a protection factor (OS, HR 0.75; PFS, HR 0.84). Finally, uni- and multivariable showed a statistically significant inverse association of CB with ABCG1-CE (OR 0.62), as with IL-6 (OR 0.13) and IL-10 (OR 0.10). In-depth characterization of the interplay between blood cholesterol metabolism and immune-inflammatory cytokines might provide novel insights into the complex relationship among cancer, inflammation, lipids profile, and response to immunotherapy.

Liquid Biopsy and 18F-FDG PET/CT Derived Parameters as Predictive Factors of Osimertinib Treatment in Advanced EGFR-Mutated NSCLC.

OBJECTIVES: Despite the outstanding results achieved by osimertinib for the treatment of advanced EGFR-mutated NSCLC, the development of resistance is almost inevitable. While molecular mechanism responsible for osimertinib resistance are being mostly revealed, the definition of predictive biomarkers is crucial in order to identify patients at higher risk of progression and optimize treatment strategy. MATERIALS AND METHODS: This is a prospective single-center study aimed to assess the potential role of liquid biopsy and 18F-FDG PET/CT derived metabolic parameters as noninvasive predictive biomarkers of osimertinib outcomes in advanced EGFR-mutated NSCLC patients. Patients underwent blood samples for ctDNA analysis at baseline, after 15 days and 1 month (t1) of osimertinib. 18F-FDG PET/CT was performed at baseline and after 1 month of osimertinib. RESULTS: Seventy-two advanced EGFR-mutated NSCLC patients treated with osimertinib in first (n = 63) and in second-line (n = 9) were prospectively enrolled. Baseline positive shedding status was significantly associated with a shorter progression-free survival (PFS) (9.5 vs. 29.2 months, P = .031). Early metabolic response (MR) led to improved PFS (16.8 vs. 5.5 months, P = .038) and OS (35.2 vs. 15.3 months, P = .047). Early MR was significantly correlated with subsequent radiologic response (P = .010). All 18F-FDG PET/CT baseline parameters were significantly related to baseline EGFR activating mutation allele frequency. Both clearance and no detection of EGFR at t1 were significantly associated with MR (P = .001 and P = .004, respectively). CONCLUSION: Molecular and 18F-FDG PET/CT derived metabolic parameters might represent a useful tool to predict osimertinib outcome in advanced EGFR-mutated NSCLC patients.

Multiple targets, germline BRCA1 mutation and HRD in a lung cancer patient: Molecular considerations and treatment decision-making.

INTRODUCTION: Several biomarkers are currently available to address targeted treatments in cancer patients, with lung malignancies representing one of the best examples. CASE DESCRIPTION: We report the case of a patient affected by advanced non-small cell lung cancer with an uncommon histology and a complex biology. The use of a large next-generation sequencing (NGS) NGS panel allowed us to identify an extremely rare BRAF mutation (V600Q), a MET amplification, a high tumor mutational burden, a germline pathogenetic BRCA1 mutation and a homologous recombination deficiency through RAD51 assay. The treatment decision was driven by the abundance of molecular information. CONCLUSIONS: This case highlights that an attentive and critical evaluation of molecular reports is key for the tailoring of treatment algorithms at the patient-level scale.

Intrinsic Resistance to Osimertinib in EGFR Mutated NSCLC Cell Lines Induced by Alteration in Cell-Cycle Regulators.

BACKGROUND: Cell-cycle regulators are mutated in approximately 40% of all cancer types and have already been linked to worse outcomes in non-small cell lung cancer adenocarcinomas treated with osimertinib. However, their exact role in osimertinib resistance has not been elucidated. OBJECTIVE: In this study, we aimed to evaluate how the CDK4/6-Rb axis may affect the sensitivity to osimertinib. METHODS: We genetically increased the level of CCND1 (Cyclin D1) and reduced the levels of CDKN2A (p16) in two different adenocarcinoma cell lines, PC9 and HCC827. We also retrospectively evaluated the outcome of patients with epidermal growth factor receptor-mutated advanced non-small cell lung cancer depending on their level of Cyclin D1 and p16. RESULTS: The modified clones showed higher proliferative capacity, modifications in cell-cycle phases, and higher migratory capacity than the parental cells. Cyclin D1-overexpressing clones were highly resistant to acute osimertinib treatment. CDKN2A knockdown conferred intrinsic resistance as well, although a longer time was required for adaption to the drug. In both cases, the resistant phenotype was epidermal growth factor receptor independent and associated with a higher level of Rb phosphorylation, which was unaffected by osimertinib treatment. Blocking the phosphorylation of Rb using abemaciclib, a CDK4/6 inhibitor, exerted an additive effect with osimertinib, increasing sensitivity to this drug and reverting the intrinsic resistant phenotype. In a group of 32 patients with epidermal growth factor receptor-mutated advanced non-small cell lung cancer, assessed for Cyclin D1 and p16 expression, we found that the p16-deleted group presented a lower overall response rate compared with the control group. CONCLUSIONS: We conclude that perturbation in cell-cycle regulators leads to intrinsic osimertinib resistance and worse patient outcomes.

Relationship Between the Diffusing Capacity of the Lung for Carbon Monoxide (DLCO) and Lung Adenocarcinoma Patterns: New Possible Insights.

INTRODUCTION: This study aimed to evaluate a potential relationship between the diffusing capacity of the lung for carbon monoxide (DLCO) and the aggressiveness of lung adenocarcinoma (ADC). METHODS: Patients who underwent radical surgery for lung ADC between 2001 and 2018 were retrospectively reviewed. DLCO values were dichotomized into DLCOlow (<80% of predicted) and DLCOnormal (≥80%). Relationships between DLCO and ADC histopathological features, clinical features, as well as with overall survival (OS), were evaluated. RESULTS: Four-hundred and sixty patients were enrolled, of which 193 (42%) were included in the DLCOlow group. DLCOlow was associated with smoking status, low FEV1, micropapillary and solid ADC, tumour grade 3, high tumour lymphoid infiltrate and presence of tumour desmoplasia. In addition, DLCO values were higher in low-grade ADC and progressively decreased in intermediate and high-grade ADC (p=0.024). After adjusting for clinical variables, at multivariable logistic regression analysis, DLCOlow still showed a significant correlation with high lymphoid infiltrate (p=0.017), presence of desmoplasia (p=0.065), tumour grade 3 (p=0.062), micropapillary and solid ADC subtypes (p=0.008). To exclude the association between non-smokers and well-differentiated ADC, the relationship between DLCO and histopathological ADC patterns was confirmed in the subset of 377 former and current smokers (p=0.021). At univariate analysis, gender, DLCO, FEV1, ADC histotype, tumour grade, stage, pleural invasion, tumour necrosis, tumour desmoplasia, lymphatic and blood invasion were significantly related with OS. At multivariate analysis, only gender (p<0.001), tumour stage (p<0.001) and DLCO (p=0.050) were significantly related with the OS. CONCLUSIONS: We found a relationship between DLCO and ADC patterns as well as with tumour grade, tumour lymphoid infiltrate and desmoplasia, suggesting that lung damage may be associated with tumour aggressiveness.