Noëlle Weingertner

Microscopic N2 disease exhibits a better prognosis in resected non-small-cell lung cancer

OBJECTIVES The management of pIIIA-N2 non-small-cell lung cancer (NSCLC) is still controversial. In particular, there are wide variations in overall survival (OS), suggesting the existence of subgroups among N2 patients. We aimed to evaluate the prognostic value of microscopic pN2 in NSCLC. METHODS Between 1996 and 2015, the data from all 982 pathologically stage IIIA-N2 patients who underwent surgery with curative intent for NSCLC were retrospectively reviewed. Microscopic pN2 disease was defined as a nodal metastasis ranging from 0.2 to 2 mm in size. RESULTS With a median follow-up of 17 months (2-101), the 5-year OS for the whole cohort was 31%. Microscopic N2 was observed in 309 (31.5%) patients. Microscopic N2 was associated with better median OS compared with macroscopic N2 [42 months (95% CI 36.85-47.15) vs 23 months (95% CI 19.7-26.29), P < 0.0001, with a corresponding 5-year OS rate of 39 and 21%, respectively]. In multivariate analysis, microscopic N2 remained a favourable independent prognostic factor [HR 0.681 (95% CI 0.481-0.967), P = 0.03]. The median OS of microscopic N2 patients who benefitted from simple follow-up was significantly better than those who underwent chemotherapy, radiation therapy or both [43 months (95% CI 24.22-61.78) vs 22 months (95% CI 17.43-26.47) vs 31 months (95% CI 27.66-34.34) vs 16 months (95% CI 14.6-17.4), P = 0.008]. CONCLUSION Microscopic N2 seems to be associated with better prognosis in patients with pIIIA-N2 NSCLC and these could benefit from a simple follow-up. Prospective cohort studies are necessary to confirm these preliminary results.

Germ-line exon 21 EGFR mutations, V843I and P848L, in nonsmall cell lung cancer patients

To the Editor: Somatic epidermal growth factor receptor ( EGFR ) mutations are now routinely integrated in the molecular diagnosis of nonsmall cell lung cancers (NSCLC) [1, 2]. Thus, germ-line EGFR mutations are rarely mentioned or looked for in the context of patients with a family history of cancer, as their association with NSCLC familial cancer risk is not well established. Moreover, the predictive value of these mutations for response to EGFR tyrosine kinase inhibitors (TKIs) is not well known [3]. We report here two different heterozygous germ-line EGFR variants identified in two Caucasian NSCLC patients, who demonstrated different responses to EGFR-TKI. A 63-year-old Caucasian, male former smoker with no family history of cancer (fig. 1a), was admitted for dyspnoea in August 2011, leading to discovery of a lower left lobe lung tumour and pleural effusion. Trans-thoracic biopsy diagnosed an invasive, acinar-predominant adenocarcinoma, classified cT2a N3 M1a (stage IV). Molecular analyses of the tumour by direct sequencing identified two concomitant heterozygous EGFR exon 21 mutations, L858R and V843I, confirmed in two independent experiments (fig. 1b). The V843I variant, but not L858R, was also detected in DNA obtained from a blood sample, with written informed consent, confirming a germ-line mutation (fig. 1c). Following treatment with cisplatin and pemetrexed, the patient relapsed in December 2012 with vertebral metastasis. An EGFR-TKI (erlotinib) was initiated, resulting in a stable disease for 9 months. Figure 1. a–c) Case 1, with epidermal growth factor receptor ( EGFR ) exon 21 mutations (V843I and L858R). a) Pedigree chart. The black case corresponds to the index patient. b) DNA sequencing electrophoretograms for DNA obtained from lung tumour tissue identifying EGFR exon 21 mutations; both mutations are present. c) DNA sequencing electrophoretograms for DNA obtained from blood, identifying one EGFR exon 21 mutation, the V834I variant, is present and confirming …

Adequately defining tumor cell proportion in tissue samples for molecular testing improves interobserver reproducibility of its assessment

Gene mutation status assessment of tumors has become standard practice in diagnostic pathology. This is done using samples comprising tumor cells but also non-tumor cells, which may dramatically dilute the proportion of tumor DNA and induce false negative results. Increasing sensitivity of molecular tests presently allows detection of a targeted mutation in a sample with a small percentage of tumor cells, but assessment of tumor cellularity remains essential to adequately interpret the results of molecular tests. Comprehensive tumor cell counting would provide the most reliable approach but is time consuming, and therefore rough global estimations are used, the reliability of which has been questioned in view of their potential clinical impact. The French association for quality assurance in pathology (AFAQAP) conducted two external quality assurance schemes, partly in partnership with the French group of oncology cytogenomics (GFCO). The purpose of the schemes was to (1) evaluate how tumor cellularity is assessed on tissue samples, (2) identify reasons for discrepancies, and (3) provide recommendations for standardization and improvement. Tumor cell percentages in tissue samples of lung and colon cancer were estimated by 40–50 participants, on 10 H&E virtual slides and 20 H&E conventional slides. The average difference between lowest and highest estimated percentage was 66. This was largely due to inadequate definition of cellularity, reflecting confusion between the percentage of tumor cells and the percentage of the area occupied by tumor in the assessed region. The widest range of interobserver variation was observed for samples with dense or scattered lymphocytic infiltrates or with mucinous stroma. Estimations were more accurate in cases with a low percentage of tumor cells. Macrodissection of the most homogeneous area in the tissue reduced inter-laboratory variation. We developed a rating system indicating potential clinical impact of a discrepancy. Fewer discrepancies were clinically relevant since the study was conducted. Although semi-quantitative estimations remain somewhat subjective, their reliability improves when tumor cellularity is adequately defined and heterogeneous tissue samples are macrodissected for molecular analysis.

Correlation between MET protein expression and MET gene copy number in a Caucasian cohort of non-small cell lung cancers according to the new IASLC/ATS/ERS classification

Summary MET pathway is a promising target in non-small cell lung cancers (NSCLC) requiring companion tests. The aim of this study was to compare MET expression/gene copy number in a Caucasian population of NSCLC patients. We analysed 201 NSCLC, with 141 adenocarcinomas classified according to 2011 IASLC recommendations, for MET expression by immunohistochemistry (IHC) and gene copy number (GCN) by silver in situ hybridisation (SISH) on tissue microarrays. Mutations in EGFR, KRAS, BRAF, HER2, PIK3CA genes and ALK rearrangements were determined. MET overexpression was observed in 44% and a high MET GCN (≥5 copies) in 14%. MET CGN was correlated with MET expression, regardless of IHC scores (p < 0.001) but only 31% of MET overexpressed cases were SISH positive. MET overexpression/GCN number was more frequent in ADC than the other types (p < 0.001), the highest in high grade (74%/34%) and sarcomatoid ADC (86%/43%). Mutations of current genes or ALK rearrangements were identified in overexpressed or amplified MET cases. MET overexpression was an independent prognostic factor for overall survival in non-smoker NSCLC in univariate (p = 0.01) and multivariate (p = 0.01) analyses. MET overexpression is more frequent than MET high GCN, particularly in high grade ADC, regardless of EGFR, KRAS, BRAF, HER2, PIK3CA and ALK status in NSCLC.

Clinical usefulness of 18F–FDG PET/CT for initial staging and assessment of treatment efficacy in patients with lymph node tuberculosis

INTRODUCTION Few studies have evaluated the promising role of 18F-fluoro-2-deoxy-D-glucose positron emission tomography (PET) and PET/computed tomography FDG PET/CT in evaluating and monitoring treatment response in patients with lymph node tuberculosis (LNTB). The aim of this clinical investigation was to assess the clinical usefulness of FDG PET/CT for initial tuberculosis staging and to determine the prognostic value of the decrease of 18F-FDG uptake during antibiotic treatment in LNTB patients. METHODS We retrospectively reviewed 18 cases of LNTB admitted at a single center from 2004 to 2014. Medical records of patients who underwent two FDG PET/CT (>6 months interval), at initial staging and at the end of therapy were reviewed to determine the impact of FDG PET/CT on initial management of LNTB and response to therapy. Statistical analysis was performed using linear mixed-effects model. RESULTS Thirteen cases of disseminated LNTB and five cases of localized LNTB were included in the study. Initial FDG PET/CT allowed guided biopsy for initial diagnosis in 5 patients and identified unknown extra-LN TB sites in 9 patients. Visual analysis follow-up of FDG PET/CT showed a complete metabolic response in 9/18 patients (all of whom were cured), a partial response in 7/18 (5 of whom were cured) and no response in 2/18 (all of whom were not cured). The semi-quantitative evaluation of 18F-FDG intensity decrease based on the maximum standardized uptake value (SUVmax), compared to targeted estimated decrease allowed to predict correctly a complete response to treatment in 14/18 cases. CONCLUSION FDG PET/CT allows an accurate pre-therapeutic mapping of LNTB and helps for early TB confirmation. The SUVmax follow up is a potential tool for monitoring the treatment response.

Aggressive digital papillary adenocarcinoma: A clinicopathological study of 19 cases

Background: Aggressive digital papillary adenocarcinomas (ADPA) are malignant tumors of sweat glands having recurrence/metastatic potential. Objective: We sought to describe the clinical/histopathological characteristics of a series of ADPA. Methods: This is a retrospective case series of 19 ADPA. Results: The tumors occurred in 17 men and 2 women (mean age: 47 years). They involved digits (15), big toe (3), and palm (1), and measured from 3 to 30 mm. They were mostly solid and cystic, with papillary projections and tubular structures. Atypia was mostly mild to moderate. Tumors tested positive for p63, keratin 7, keratin 77 (eccrine duct‐specific), PHLDA1, and epithelial membrane antigen in most cases, and for carcinoembryonic antigen, smooth muscle actin, S100 protein, estrogen, progesterone, and androgen receptors in 50%. Mean Ki67 proliferation index was 15%. Local recurrence was observed in 4 cases. One patient had axillary lymph node metastasis. Histopathologic parameters were not predictive of evolution. Conservative surgical treatment, performed in 7 of 19 cases, did not result in more recurrences than amputation. Limitations: The study was retrospective and the number of cases is small. Conclusion: ADPA are histologically variable, but papillary projections are always present. Keratin 77 expression suggests an eccrine origin. P63 is helpful to exclude metastasis. Conservative surgery may be sufficient in some cases.

Intralymphatic CD30+ T‐cell proliferation during DRESS: a mimic of intravascular lymphoma

We describe the case of a patient presenting with drug rash with eosinophilia and systemic symptoms (DRESS), where cutaneous biopsy revealed intravascular atypical lymphocytes suggestive of lymphoma.

Lung Adenocarcinoma with Pulmonary Miliary Metastases and Complex Somatic Heterozygous EGFR Mutation

The pretreatment detection of an activating mutation of EGFR is now routinely performed in metastatic nonsquamous non-small cell lung cancer (NSCLC). The therapeutic impact of such a detection is major, as patients with advanced NSCLC exhibiting a mutation of exon 19 or 21 will benefit from EGFR-tyrosine kinase inhibitors (TKI). The presence of an EGFR resistance mutation, such as T790M in EGFR-TKI-naïve patients, is seldom looked for and is related either to a germinal mutation or to somatically mutated subclones. It has a negative predictive impact. We present the case of a patient with a lung papillary adenocarcinoma and miliary intrapulmonary metastases whose tumor displays a somatic complex heterozygous EGFR mutation, combining L858R (exon 21) and a primary resistance mutation T790M (exon 20), both detected by direct sequencing.

Characterization of the transcriptional and metabolic responses of pediatric high grade gliomas to mTOR-HIF-1α axis inhibition

Pediatric high grade glioma (pHGGs), including sus-tentorial and diffuse intrinsic pontine gliomas, are known to have a very dismal prognosis. For instance, even an increased knowledge on molecular biology driving this brain tumor entity, there is no treatment able to cure those patients. Therefore, we were focusing on a translational pathway able to increase the cell resistance to treatment and to reprogram metabolically tumor cells, which are, then, adapting easily to a hypoxic microenvironment. To establish, the crucial role of the hypoxic pathways in pHGGs, we, first, assessed their protein and transcriptomic deregulations in a pediatric cohort of pHGGs and in pHGGs cell lines, cultured in both normoxic and hypoxic conditions. Secondly, based on the concept of a bi-therapy targeting in pHGGs mTORC1 (rapamycin) and HIF-1α (irinotecan), we hypothesized that the balanced expressions between RAS/ERK, PI3K/AKT and HIF-1α/HIF-2α/MYC proteins or genes may provide a modulation of the cell response to this double targeting. Finally, we could evidence three protein, genomic and metabolomic profiles of response to rapamycin combined with irinotecan. The pattern of highly sensitive cells to mTOR/HIF-1α targeting was linked to a MYC/ERK/HIF-1α over-expression and the cell resistance to a major hyper-expression of HIF-2α.Pediatric high grade glioma (pHGGs), including sus-tentorial and diffuse intrinsic pontine gliomas, are known to have a very dismal prognosis. For instance, even an increased knowledge on molecular biology driving this brain tumor entity, there is no treatment able to cure those patients. Therefore, we were focusing on a translational pathway able to increase the cell resistance to treatment and to reprogram metabolically tumor cells, which are, then, adapting easily to a hypoxic microenvironment. To establish, the crucial role of the hypoxic pathways in pHGGs, we, first, assessed their protein and transcriptomic deregulations in a pediatric cohort of pHGGs and in pHGGs cell lines, cultured in both normoxic and hypoxic conditions. Secondly, based on the concept of a bi-therapy targeting in pHGGs mTORC1 (rapamycin) and HIF-1α (irinotecan), we hypothesized that the balanced expressions between RAS/ERK, PI3K/AKT and HIF-1α/HIF-2α/MYC proteins or genes may provide a modulation of the cell response to this double targeting. Finally, we could evidence three protein, genomic and metabolomic profiles of response to rapamycin combined with irinotecan. The pattern of highly sensitive cells to mTOR/HIF-1α targeting was linked to a MYC/ERK/HIF-1α over-expression and the cell resistance to a major hyper-expression of HIF-2α.

Myxoid liposarcoma with heterologous components: dedifferentiation or metaplasia? A FISH-documented and CGH-documented case report.

Heterologous differentiation in myxoid liposarcoma is a rare phenomenon. Few cases have been reported thus far, often without molecular assays, and the concept of “dedifferentiated” myxoid liposarcoma remains controversial. We describe a primary myxoid liposarcoma with chondroid and osseous components affecting the right thigh of a 27-year-old woman. We wondered whether these areas represented dedifferentiated components or simply metaplasia, and performed fluorescent in situ hybridization and array comparative genomic hybridization assays in the myxoid liposarcoma component and chondroid component. Fluorescent in situ hybridization analysis demonstrated a DDIT3 gene rearrangement in both components; array comparative genomic hybridization analysis did not detect any gain or loss of DNA regions in both components. Our results, demonstrating that both components have the same molecular alterations, suggest that heterologous components seen in some myxoid liposarcomas reflect a metaplastic phenomenon and not a real dedifferentiation phenomenon, challenging the concept of “dedifferentiated” myxoid liposarcoma.