ALK Gene Translocation Research Articles

Long-term disease control in a patient with ALK-positive non-small cell lung cancer

Non-small cell lung cancer is a very heterogeneous group of diseases. When choosing an effective patient management strategy, an oncologist focuses on the stage of the disease, the morphological form of the tumor, as well as its molecular genetic markers. Most of the targeted mutations in lung cancer today are in adenocarcinoma. The standard for detecting this type of cancer in 2022 is the determination of mutations in the EGFR genes (18-21 exons) and BRAF (V600E), translocations of the ALK and ROS1 genes, and determination of PD-L1 status regardless of gender, age, and history of smoking. Often, lung cancer is detected in the advanced stages, but the detection of ALK gene translocation can give the patient a high chance of a longer life expectancy and long-term control of the disease. In this article, on the example of a clinical case of a patient with ALK-positive lung adenocarcinoma, a multidisciplinary approach to the management of cancer patients, long-term control of the disease with the use of the second-generation targeted medication alectinib, as well as treatment options for disease progression are demonstrated.

Inflammatory myofibroblastic tumors of the urinary bladder: a clinicopathological study of ten cases

0bjective To investigate the clinicopathological features,immunohistochemical phenotypes, molecular genetic alterations,diagnosis and differential diagnosis of inflammatory myofibroblastic tumor (IMT) of the urinary bladder. Methods: Ten cases of IMT of the urinary bladder (three cases at Ningbo Diagnostic Pathology Center from September 2011 to December 2020, five in-house diagnosed cases and two consultation cases at Shanghai Rui Jin Hospital from June 2011 to December 2020) were collected retrospectively. The clinicopathologic features and immunophenotypic profiles were studied by light microscopy and immunohistochemistry (EnVision method). The translocation of ALK gene was detected by fluorescence in situ hybridization (FISH). Results: Of the 10 patients, eight were male and two were female. The patients' age range was 16 to 62 years (median 36 years).The main clinical presentation was hematuria and urinary irritation. Three cases were located at the dome of the urinary bladder, four cases were in the left lateral wall and the remaining three cases were in the right lateral wall. The tumor size ranged from 1.5 cm to 8.5 cm. In eight cases, the tumors were mainly submucosal, and in some cases extending to the muscular layer of the urinary bladder. In two cases, the tumors were mainly located in the muscular layer and focally extended to the submucosa and adventitia. Histologically, four cases had the nodular fasciitis-like pattern, three cases had fibrohistiocytoma-like pattern, two cases had mixed histologic patterns and the remaining case showed leiomyosarcoma-like histologic features. Immunohistochemically, the tumor cells expressed SMA (10/10),calponin (9/10),desmin (6/10) and CKpan (9/10). Cytoplasmic staining for ALK1 and ALK (5A4) was detected in 7 of 10 cases and 8 of 10 cases, respectively. Nuclear and cytoplasmic staining for ALK (D5F3) was detected in 7 of 10 cases. Among eight cases with material available for FISH analysis, ALK rearrangement was present in five cases. Follow-up data were available in eight patients and none had local recurrence nor distant metastasis. Conclusion: IMT of the urinary bladder is an uncommon mesenchymal neoplasm with intermediate malignant potential.It has special clinicopathologic features, and a minority of cases have local tumor recurrence.

LENT score in prognostic assessment of malignant pleural effusion – the impact of target therapy

Introduction: Malignant pleural effusion (MPE) is a common manifestation in patients with advanced lung cancer. The LENT score was developed as a risk stratification system to predict the survival of these patients. However, following the discovery of molecular markers and a new era of personalized therapy, prognostic estimation became a challenging exercise. The aim of this study was to evaluate the performance of LENT score in predicting MPE survival in EGFR and ALK mutated lung adenocarcinoma. Methods: A retrospective single-center study of patients with MPE from lung adenocarcinoma followed between January 2008 to December 2018. Results: Forty-two patients were included in the study (mean age 76.4 ± 12.6 years, 52% female). Of these patients, 29% exhibited EGFR gene mutation or ALK gene translocation and received tyrosine kinase inhibitor therapy (TKI), in contrast to 71% of patients without identification of mutational factors and receiving conventional chemotherapy. Based on LENT score, in the sub-group treated with conventional chemotherapy, 67% had a moderate-risk category and 33% a high-risk category, with a median overall survival (OS) of 109 (31-406) and 36 (11-77) days, respectively. In the sub-group treated with targeted therapy, 75% were in a moderate-risk category and 25% in a high-risk category with a median OS of 1033 (245-1710) and 238 (27-not available) days, respectively. Patients receiving targeted therapy had a longer survival than patients receiving conventional chemotherapy in all LENT score risk categories (p<0.05). Conclusions: OS in patients with MPE due to lung adenocarcinoma was similar to that predicted by the LENT score, except for patients with EGFR mutation or ALK translocation. In this subgroup, the LENT score seems to underestimate the prognosis. Although this study has limitations regarding sample size, it does reveal, in the present time, some inaccuracy of the LENT score, demonstrating that it needs to be reviewed and revalidated in view of recent therapeutic advances.

Sensitivity and specificity of ALK immunohistochemistry in the identification of ALK gene fusions in bone and soft tissue sarcomas other than in inflammatory myofibroblastic tumours; expanding the spectrum of ALK gene translocations

Sensitivity and specificity of ALK immunohistochemistry in the identification of ALK gene fusions in bone and soft tissue sarcomas other than in inflammatory myofibroblastic tumours; expanding the spectrum of ALK gene translocations

Recent Topics on Primary Bone and Soft Tissue Tumors and Metastatic Bone Tumors

Abstract Background: Recently, some drugs such as Pazopanib, Eribulin and Trabectedin can be used for advanced soft tissue sarcoma in Japan, but there are still few drugs useful for primary bone and soft tissue tumors. In metastatic bone tumors, bone modifying agents such as Zoledronic acid and Denosumab reduce skeletal related events (SREs) and are used clinically. Methods: I summarize and comment on recent findings from meetings and papers on primary bone and soft tissue tumors and metastatic bone tumors. Results and Conclusion: A phase III study was conducted using Olaratumab in addition to Doxorubicin as a primary treatment for advanced soft tissue tumors. Olaratumab plus Doxorubicin therapy did not show any advantage in the primary end point of survival in comparison with Doxorubicin alone. Infantile fibrosarcoma with the NTRK gene translocation and inflammatory myofibroblastic tumors with the ALK gene translocation are expected to obtain benefit from use of molecular target drugs. TRK inhibitors and ALK inhibitors have been used in clinical trials and some good results have been reported. Molecular targeting drugs have been used for advanced osteosarcoma as a second line treatment, and the median disease-free survival was relatively good at 4.0 months with Sorafenib, 16.4 weeks with Regorafenib, and 6.2 months with Cabozantinib. In metastatic bone tumors, an attempt has been made to extend the administration interval of Zoledronic acid, and the noninferiority of 12 weeks' administration has been reported as compared with 4 weeks' administration for the occurrence of SREs in breast cancer.

Combined Cellular and Biochemical Profiling to Identify Predictive Drug Response Biomarkers for Kinase Inhibitors Approved for Clinical Use between 2013 and 2017

Kinase inhibitors form the largest class of precision medicine. From 2013 to 2017, 17 have been approved, with 8 different mechanisms. We present a comprehensive profiling study of all 17 inhibitors on a biochemical assay panel of 280 kinases and proliferation assays of 108 cancer cell lines. Drug responses of the cell lines were related to the presence of frequently recurring point mutations, insertions, deletions, and amplifications in 15 well-known oncogenes and tumor-suppressor genes. In addition, drug responses were correlated with basal gene expression levels with a focus on 383 clinically actionable genes. Cell lines harboring actionable mutations defined in the FDA labels, such as mutant BRAF(V600E) for cobimetinib, or ALK gene translocation for ALK inhibitors, are generally 10 times more sensitive compared with wild-type cell lines. This sensitivity window is more narrow for markers that failed to meet endpoints in clinical trials, for instance CDKN2A loss for CDK4/6 inhibitors (2.7-fold) and KRAS mutation for cobimetinib (2.3-fold). Our data underscore the rationale of a number of recently opened clinical trials, such as ibrutinib in ERBB2- or ERBB4-expressing cancers. We propose and validate new response biomarkers, such as mutation in FBXW7 or SMAD4 for EGFR and HER2 inhibitors, ETV4 and ETV5 expression for MEK inhibitors, and JAK3 expression for ALK inhibitors. Potentially, these new markers could be combined to improve response rates. This comprehensive overview of biochemical and cellular selectivities of approved kinase inhibitor drugs provides a rich resource for drug repurposing, basket trial design, and basic cancer research.

Clinicopathologic features and immunophenotype of pseudosarcomatous myofibroblastic proliferation of urinary bladder

Objective: To investigate the clinicopathologic features, immunohistochemical phenotypes and biological behavior of pseudosarcomatous myofibroblastic proliferation (PMP) of the urinary bladder which may be misdiagnosed as a malignant neoplasm and undergo extensive treatment. Methods: Six cases of PMP of the urinary bladder were collected from 2001 to 2016 at Beijing Tiantan Hospital, Capital Medical University. The clinicopathologic features and immunophenotypic profile were studied by histopathological and immunohistochemical investigations with clinical follow-up. At the same time, the translocation of ALK gene was detected by fluorescence in situ hybridization (FISH). Immunohistochemistry was carried out using EnVision method for the expression of AE1/AE3, vimentin, EMA, SMA, Caldesmon, Calponin, desmin, ALK, Ki-67, MyoD1, myoglobin, CD34, S-100, CD117, CK7, CK20, GATA3, p63 and CK5/6. The related literature was reviewed. Results: There were two male and four female patients, significantly more common in women. The age of the patients was 27 to 53 years, and the median age was 35 years. The main clinical symptom was painless gross hematuria, one case with dysuria, and one case showed recurrent cystitis. There was no history of surgery and trauma. Follow-up ranged from 4 months to 13 years and showed five cases without recurrence and one case with recurrence. Microscopy showed submucosal lesion with inflammatory exudate and bleeding on the surface, in some cases extending to the superficial muscles of the bladder wall. The lesion was characterized by the proliferation of plump spindle cells, which were loose or dense in arrangement. There were varying degrees of acute and chronic inflammatory cells infiltration in the myxoid matrix. Spindle cells arranged in disorder, or a dense stranding, especially abundant in the cell region. The median mitotic rate was <2/10 HPF cells, but there were no pathological mitotic figures and without nuclear atypia in most spindle cells. Spindle cells with eosinophilic cytoplasm showed long tapering cytoplasmic projections. Oval or short spindle nuclei had vacuolization with prominent nucleoli, looking like ganglionic cells. There were scarce collagen fibers, and a few spindle cells degenerated with chromatin blurred. Some areas showed a granuloma-like pattern and neutrophils within vascular cavity. Immunohistochemically, the spindle cells were diffusely positive for vimentin, SMA and caldesmon. CKpan was strongly and diffusely positive. Desmin and calponin expression was varying. Ki-67 positive cells were about 35% to 55%, but the spindle cells were negative for myoglobin, S-100, CD117, CD34, p63 and CK5/6. FISH test showed that there was no ALK isolated signal in 6 cases of PMP, and so no positive cases were found. Conclusions: PMP of the urinary bladder is a benign non-neoplastic myofibroblastic proliferative lesion. Morphology is extremely easy to be misdiagnosed as malignant tumors, and therefore more attention should be paid to avoid this misdiagnosis.

P3.02-055 Detecting ALK, ROS1 and RET Gene Translocations in Non-Small Cell Lung Cancer (NSCLC) with the NanoString Platform

Identification of ALK, ROS1 and RET fusions is critical for guiding target therapy of lung cancers. In this study, we evaluated the transcript-based nanoString assay for detection of ALK fusions compared to immunohistochemistry (IHC) and FISH methods, and the simultaneous detection of ROS1 and RET transcripts in formalin-fixed and paraffin embedded tissues (FFPE).

Recurrent Cytogenetic Abnormalities in Non-Hodgkin's Lymphoma and Chronic Lymphocytic Leukemia.

Characteristic chromosomal translocations are found to be associated with subtypes of B-cell non-Hodgkin lymphoma (NHL), for example t(8;14)(q24;q32) and Burkitt lymphoma, t(14;18)(q32;q21) and follicular lymphoma, and t(11;14)(q13;q32) in mantle cell lymphoma. Only few recurrent cytogenetic aberrations have been identified in the T-cell NHL and the best known is the ALK gene translocation t(2;5)(p23;q35) in anaplastic large cell lymphoma. Since lymph node or other tissue is seldom submitted for conventional cytogenetics study, alternative approaches for translocation detection are polymerase chain reaction (PCR) or fluorescence in situ hybridization (FISH). FISH is more sensitive than PCR in the detection of lymphoma translocations since directly labeled large FISH probes that span the translocation breakpoints are used. Although the recurrent chromosomal abnormalities in NHL are not completely sensitive and specific for disease entities, unlike the scenario in acute leukemia, cytogenetic and molecular genetic study is commonly used to aid lymphoma diagnosis and classification. Currently, the main clinical utility is in the employment of interphase FISH panels to predict disease aggressiveness to guide therapy, for example identification of double-hit lymphoma, or in prognostication, for example risk-stratification in chronic lymphocytic leukemia. The recent application of high-throughput sequencing to NHL not only advances the understanding of disease pathogenesis and classification, but allows the discovery of new drug targets, such as BRAF gene inhibition in hairy cell leukemia. Coupled with the increasing availability of novel molecular targeted therapeutic agents, the hope for the future is to translate the genetics and genomics information to achieve personalized medicine in NHL.

Abstract 4675: Detection of ALK, ROS1, and RET translocations in non-small cell lung cancer (NSCLC) patients by intragenic differential expression analysis

Abstract BACKGROUND: ALK, ROS1, and RET translocations are frequently detected in NSCLC patients. Crizotinib, a tyrosine kinase inhibitor (TKI), was approved by the FDA in 2011 to treat NSCLC in patients harboring ALK translocations as detected by an FDA-approved assay. However, the FDA-approved ALK FISH assay is technically challenging, with failures due to pre-analytic variables. Another approach, intragenic differential expression (IDE), detects translocations by comparing expression levels of the 5′ end with the 3′ end of target gene transcripts. In this study we developed and evaluated a rapid IDE assay to screen for ALK, ROS1, and RET translocations, independent of the fusion partner. METHODS: A total of 419 samples (408 randomly-selected NSCLC clinical samples, ALK positive and ROS1 positive cell lines (2 each), and 7 previously-tested RET-positive clinical samples) were used to develop and evaluate performance characteristics of the IDE assays. To determine IDE scores, levels of ALK, ROS1, and RET expression were first determined by quantitative RT-PCR measurement of the 5′- and 3′- ends of the respective transcripts. The differences in expression levels were calculated as ΔCt (Ct5′ - Ct3′). High ΔCt values indicate presumptive presence of gene translocations. 212/408 NSCLC samples were analyzed by ALK FISH and EML4-ALK RT-PCR, and 196/408 samples were analyzed by EML4-ALK RT-PCR. RESULTS: Thirty-one of the 408 (7.6%) clinical samples tested positive for ALK rearrangements by IDE. Among them, 20 were confirmed by FISH and/or EML4-ALK (true positive, 64.5%), while 11 were negative by FISH and/or EML4-ALK (false positive, 35.5%). One of 10 ALK FISH positive samples tested negative by both ALK IDE and EML4-ALK RT-PCR analysis (false negative), while one of 202 FISH-negative sample tested positive by both EML4-ALK and ALK IDE. ALK IDE exhibited 94.5% (189/200) concordance with ALK FISH and 96.0% (356/371) concordance with the EML4-ALK assay. For ROS1, both ROS1-positive cell lines and 4/408 (1.0%) NSCLC samples tested positive for ROS1 by IDE. Among the 4 IDE-positive NSCLC samples, 1 was confirmed by ROS1 FISH. For RET, all 7 known positives and 10/408 (2.5%) NSCLC samples tested positive by IDE. Three of six RET IDE positive NSCLC samples were confirmed by RET FISH. Overall, ALK, ROS1, and RET translocations were mutually exclusive in NSCLC patients. The lung IDE assay had a failure rate of 3.7%. CONCLUSION: These findings demonstrate the feasibility of using IDE to detect ALK, ROS1, and RET gene translocations. These assays may have potential as a screening tool to select patients for further confirmation by FISH for TKI-targeted therapy. The IDE concept can be applied to a wide range of somatic translocations. Citation Format: Shih-Min Cheng, Cindy Barlan, Feras Hantash, Heather R. Sanders, Patricia H. Chan, Vladimira Sulcova, Marc A. Sanidad, Kevin Qu, Joann C. Kelly, Fatih Z. Boyar, Anthony D. Sferruzza, Frederic M. Waldman. Detection of ALK, ROS1, and RET translocations in non-small cell lung cancer (NSCLC) patients by intragenic differential expression analysis. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4675. doi:10.1158/1538-7445.AM2014-4675

Molecular profiling of resected esophageal cancer and its correlation with clinical outcome.

4046 Background: The tumor related gene profiling in esophageal cancer remains unknown and requires further investigation in order to promote efficient and rapid development of molecular-target agents. The aim of this study was to evaluate the expression level and mutations of tumor related genes in resected esophageal cancer and to assess correlation of the profiling with clinical outcome. Methods: 135 consecutive patients with esophageal cancer who underwent esophagectomy at Shizuoka Cancer Center and Toyama University between October 2002 and November 2011 were analyzed. Protein expression of MET, EGFR, ALK and HGF was determined by Automated QUantification Analysis. Copy number of EGFR, PIK3CA, MET and FGFR1/2 was analyzed by real time PCR. The translocation of ALK gene and mutations of tumor related genes were evaluated by fluorescence in situ hybridisation and TruSeq Amplicon Cancer Panel, respectively. Prognostic factors associated with survival were identified by multivariate analyses using the Co...

CD30 expression in non-small cell lung cancer with and without ALK gene rearrangement.

e22146 Background: 3-5% Non-Small Cell Lung Cancer (NSCLC) harbors ALK gene translocation (ALK(+)) for which targeted ALK inhibitor has greater efficacy and tolerance than cytotoxic chemotherapy. H...

Large cell carcinoma of the lung: clinically oriented classification integrating immunohistochemistry and molecular biology

This study aimed at challenging pulmonary large cell carcinoma (LLC) as tumor entity and defining different subgroups according to immunohistochemical and molecular features. Expression of markers specific for glandular (TTF-1, napsin A, cytokeratin 7), squamous cell (p40, p63, cytokeratins 5/6, desmocollin-3), and neuroendocrine (chromogranin, synaptophysin, CD56) differentiation was studied in 121 LCC across their entire histological spectrum also using direct sequencing for epidermal growth factor receptor (EGFR) and v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations and FISH analysis for ALK gene translocation. Survival was not investigated. All 47 large cell neuroendocrine carcinomas demonstrated a true neuroendocrine cell lineage, whereas all 24 basaloid and both 2 lymphoepithelioma-like carcinomas showed squamous cell markers. Eighteen out of 22 clear cell carcinomas had glandular differentiation, with KRAS mutations being present in 39 % of cases, whereas squamous cell differentiation was present in four cases. Eighteen out of 20 large cell carcinomas, not otherwise specified, had glandular differentiation upon immunohistochemistry, with an exon 21 L858R EGFR mutation in one (5 %) tumor, an exon 2 KRAS mutation in eight (40 %) tumors, and an ALK translocation in one (5 %) tumor, whereas two tumors positive for CK7 and CK5/6 and negative for all other markers were considered adenocarcinoma. All six LCC of rhabdoid type expressed TTF-1 and/or CK7, three of which also harbored KRAS mutations. When positive and negative immunohistochemical staining for these markers was combined, three subsets of LCC emerged exhibiting glandular, squamous, and neuroendocrine differentiation. Molecular alterations were restricted to tumors classified as adenocarcinoma. Stratifying LCC into specific categories using immunohistochemistry and molecular analysis may significantly impact on the choice of therapy.

Primary non-small cell lung cancer response upon treatment with denosumab

Here we report the case of a patient with metastatic adenocarcinoma of the lung harboring an ALK gene translocation. In this patient a response of the primary tumor and metastases has been detected upon treatment with denosumab. A possible link between ALK and RANK is postulated.

Safety and activity of crizotinib for paediatric patients with refractory solid tumours or anaplastic large-cell lymphoma: a Children's Oncology Group phase 1 consortium study

Various human cancers have ALK gene translocations, amplifications, or oncogenic mutations, such as anaplastic large-cell lymphoma, inflammatory myofibroblastic tumours, non-small-cell lung cancer (NSCLC), and neuroblastoma. Therefore, ALK inhibition could be a useful therapeutic strategy in children. We aimed to determine the safety, recommended phase 2 dose, and antitumour activity of crizotinib in children with refractory solid tumours and anaplastic large-cell lymphoma. In this open-label, phase 1 dose-escalation trial, patients older than 12 months and younger than 22 years with measurable or evaluable solid or CNS tumours, or anaplastic large-cell lymphoma, refractory to therapy and for whom there was no known curative treatment were eligible. Crizotinib was given twice daily without interruption. Six dose levels (100, 130, 165, 215, 280, 365 mg/m(2) per dose) were assessed in the dose-finding phase of the study (part A1), which is now completed. The primary endpoint was to estimate the maximum tolerated dose, to define the toxic effects of crizotinib, and to characterise the pharmacokinetics of crizotinib in children with refractory cancer. Additionally, patients with confirmed ALK translocations, mutations, or amplification (part A2 of the study) or neuroblastoma (part A3) could enrol at one dose level lower than was currently given in part A1. We assessed ALK genomic status in tumour tissue and used quantitative RT-PCR to measure NPM-ALK fusion transcript in bone marrow and blood samples of patients with anaplastic large-cell lymphoma. All patients who received at least one dose of crizotinib were evaluable for response; patients completing at least one cycle of therapy or experiencing dose limiting toxicity before that were considered fully evaluable for toxicity. This study is registered with ClinicalTrials.gov, NCT00939770. 79 patients were enrolled in the study from Oct 2, 2009, to May 31, 2012. The median age was 10.1 years (range 1.1-21.4); 43 patients were included in the dose escalation phase (A1), 25 patients in part A2, and 11 patients in part A3. Crizotinib was well tolerated with a recommended phase 2 dose of 280 mg/m(2) twice daily. Grade 4 adverse events in cycle 1 were neutropenia (two) and liver enzyme elevation (one). Grade 3 adverse events that occurred in more than one patient in cycle 1 were lymphopenia (two), and neutropenia (eight). The mean steady state peak concentration of crizotinib was 630 ng/mL and the time to reach this peak was 4 h (range 1-6). Objective tumour responses were documented in 14 of 79 patients (nine complete responses, five partial responses); and the anti-tumour activity was enriched in patients with known activating ALK aberrations (eight of nine with anaplastic large-cell lymphoma, one of 11 with neuroblastoma, three of seven with inflammatory myofibroblastic tumour, and one of two with NSCLC). The findings suggest that a targeted inhibitor of ALK has antitumour activity in childhood malignancies harbouring ALK translocations, particularly anaplastic large-cell lymphoma and inflammatory myofibroblastic tumours, and that further investigation in the subset of neuroblastoma harbouring known ALK oncogenic mutations is warranted. Pfizer and National Cancer Institute grant to the Children's Oncology Group.

ALK gene translocations and amplifications in brain metastases of non-small cell lung cancer

BackgroundIncreased incidence of brain metastases (BM) in non-small cell lung cancer (NSCLC) with ALK translocations was postulated, however, ALK gene aberrations in NSCLC-BM have not been investigated so far. MethodsWe investigated ALK and EML4 gene aberrations (amplifications, translocations, inversions) by fluorescent in situ hybridization (FISH) (n=175) and ALK and EML4 protein expression by immunohistochemistry (n=221) in NSCLC BM and corresponding primary tumors. ResultsALK translocations were found in 4/151 (2.6%; 3 of them involving EML4) of BM of adenocarcinomas (AC), 1/9 (11.1%) of adenosquamous carcinomas (ASC), 0/5 of squamous cell carcinomas (SCC) and 0/10 of large cell carcinomas (LCC). Rearrangement of ALK without involvement of EML4 was seen in 1 AC-BM and rearrangement of EML4 without involvement of ALK in 3 AC-BM, 1 ASC-BM and 1 LCC. ALK amplifications without gene rearrangements were found in BM of 16/151 (10.6%) AC, 2/5 (40%) SCC, 0/9 ASC and one LCC. ALK translocation status was constant between BM and primary tumors in 16 evaluable cases including two cases with ALK–EML4 translocations Among these 16 cases ALK amplification was seen in two BM and none of the primary tumors. All cases with translocations but not with amplifications of ALK showed protein expression. We found no association of ALK gene status with patient age, gender or overall survival time. ConclusionsALK translocations and amplifications are found in approximately 3% and 11% of NSCLC-BM, respectively. While ALK translocations appear to be constant between primary tumors and BM, amplifications seem to be more prevalent in BM. ALK translocation, but not ALK amplification is associated with ALK protein overexpression. Further studies are needed to determine whether NSCLC-BM patients with ALK gene aberrations may benefit from specific inhibitor therapy.

Abstract IA5: Genetic and genomic difference in lung cancer based on ethnicity

Abstract Since the discovery of somatic mutation of the gene for the epidermal growth factor receptor (EGFR) in the non-small cell lung cancer (NSCLC), it has been known that EGFR mutation tends to occur in a certain subset of patients with a distinct clinical-pathologic feature. Namely, EGFR mutations are predominantly found in female, non-smoking patients with adenocarcinoma of East Asian origin. According to the data of 2880 patients complied from the literature, EGFR mutations are highly dependent on ethnicity (East Asians, 32% compared with Caucasians, 7%), sex (male, 10% compared with female, 38%), smoking history (never smoked, 47% compared with smoked, 7%), and histologic type (adenocarcinoma, 30% compared with other types of lung cancer, 2%) (1). In contrast, KRAS mutations predominantly occur in Caucasian patients with smoke exposure. KRAS mutation is present ∼30% of adenocarcinoma of Caucasian patients, while it is present in ∼10% of Asian patients (2). There appears to be no ethnic difference for incidence of ALK gene translocation although it is more frequent in non-smoking population similar to EGFR mutation. According to Shigematsu and Gazdar, incidence of EGFR mutations is significantly different between East Asian patients (33%) and non-Asian patients (6%) (P &amp;lt; 0.001) in their analysis of 2,347 cases (3). When limited to adenocarcinoma, this difference is also present (48% vs. 12%). They also reported that 4 of 5 Asian patients with lung cancer in the United States and Australia had EGFR mutations, suggesting that genetics may be more important than geographic factors for affecting EGFR mutations (3). The remarkable difference in prevalence of EGFR mutation in NSCLC patients between East Asian and Western population suggests that there may be differences in background risk/protective factors between these two populations. Several polymorphic variations in EGFR gene including a CA repeat in intron 1 (CA simple sequence repeat 1 (CA-SSR1) (lower number of repeats) or single nucleotide polymorphisms in the promoter region (-216(G/T or T/T) and -191 (C/A or A/A) have been identified. All these polymorphisms are associated with increased expression of the EGFR protein and are less frequent in East Asians (4). Therefore, East Asians in general make less EGFR protein. To make lung cancer to occur, EGFR gene should be mutated and amplified because mutation of the EGFR gene is a prerequisite for amplification, if a certain amount of mutated EGFR protein is necessary to activate EGFR pathway signaling. This may partly explain ethnic difference in incidence of EGFR gene mutation described above (4). We are now conducting Genome-Wide Association Study in Japanese to identify genetic locus associated with the risk of EGFR mutated and non-mutated NSCLC. In a part of the phase I study at Aichi Cancer Center [341 lung cancer cases (125 EGFR mutated and 216 EGFR wild-type) and 972 non-cancer controls] using Illumina platform-based genome scanning data, we have identified two loci showing genome-wide significance (p&amp;lt;10−8) and two loci suggestive significance (10−8∼−5) loci for the risk of EGFR mutation. For EGFR wild-type NSCLC, three loci showed genome-wide significance and four loci showed suggestive significance. Some of the loci partly explain difference in the prevalence of EGFR mutation. A risk-allele frequency of one of the loci showing association with EGFR mutated NSCLC was high in HapMap JPT (0.972) and low in HapMap CEU (0.438). We are now validating our finding in other Japanese cohorts. We believe that difference in EGFR mutation among NSCLC patients between East Asian and Western population can be explained by genetic difference.

Pathobiology and Molecular Profiling of Peripheral T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of rare diseases, usually manifesting clinical aggressiveness. Although important novel insights into the pathobiology of nodal PTCL have been gained recently from molecular profiling studies and clinico-pathological analyses, the pathogenetic molecular lesions remain to be deciphered for most entities. Angioimmunoblastic T-cell lymphoma (AITL) comprises CD4+ CXCL13+ neoplastic cells displaying overlapping immunophenotypical and molecular features with normal follicular helper T cells. This derivation might account for the presence of a prominent non-neoplastic component in AITL tissues and the clinical manifestations of the disease reflective of an immunological dysfunction. ALK+ anaplastic large cell lymphoma (ALCL), defined by ALK gene translocation with various gene partners, is composed of CD30+ ALK+ cells with a cytotoxic phenotype and usually carries a good prognosis. ALK- ALCL, now considered as a distinct disease entity, is morphologically and immunophenotypically similar to ALK+ ALCL, except for ALK expression, but has distinctive molecular features. PTCL, not otherwise specified (PTCL, NOS), the largest PTCL category, which is derived from activated CD4+ (or CD8+) T cells, is markedly heterogeneous, including at the molecular level. Gene expression profiling approaches have identified novel biomarkers of potential therapeutic interest, and suggest the existence of molecularly distinct PTCL, NOS subgroups.

Pathobiology and Molecular Profiling of Peripheral T-Cell Lymphomas

Peripheral T-cell lymphomas (PTCLs) are a heterogeneous group of rare diseases, usually manifesting clinical aggressiveness. Although important novel insights into the pathobiology of nodal PTCL have been gained recently from molecular profiling studies and clinico-pathological analyses, the pathogenetic molecular lesions remain to be deciphered for most entities. Angioimmunoblastic T-cell lymphoma (AITL) comprises CD4+ CXCL13+ neoplastic cells displaying overlapping immunophenotypical and molecular features with normal follicular helper T cells. This derivation might account for the presence of a prominent non-neoplastic component in AITL tissues and the clinical manifestations of the disease reflective of an immunological dysfunction. ALK+ anaplastic large cell lymphoma (ALCL), defined by ALK gene translocation with various gene partners, is composed of CD30+ ALK+ cells with a cytotoxic phenotype and usually carries a good prognosis. ALK– ALCL, now considered as a distinct disease entity, is morphologically and immunophenotypically similar to ALK+ ALCL, except for ALK expression, but has distinctive molecular features. PTCL, not otherwise specified (PTCL, NOS), the largest PTCL category, which is derived from activated CD4+ (or CD8+) T cells, is markedly heterogeneous, including at the molecular level. Gene expression profiling approaches have identified novel biomarkers of potential therapeutic interest, and suggest the existence of molecularly distinct PTCL, NOS subgroups.

Anaplastic lymphoma kinase (ALK 1) staining and molecular analysis in inflammatory myofibroblastic tumours of the bladder: a preliminary clinicopathological study of nine cases and review of the literature

Inflammatory myofibroblastic tumours (IMFT) may arise at any anatomical site, including lung, soft tissues, retroperitoneum and bladder. Although morphologically similar, these lesions encompass a spectrum of entities with differing aetiology, ranging from reactive/regenerative proliferations to low-grade neoplasms with a risk of local recurrence, but no significant metastatic potential. Vesical IMFT usually presents as a polypoid mass with a pale firm cut surface and can be of considerable size, mimicking a malignant tumour clinically and radiologically. Its good outcome, however, warrants conservative surgical excision, emphasising the importance of identification and distinction from malignant tumours of the bladder that may require more radical surgery and/or adjuvant therapy. We conducted a preliminary retrospective, comparative immunocytochemical study of 20 bladder tumours, including nine IMFTs, five spindle cell (sarcomatoid) carcinomas, two rhabdomyosarcomas, two leiomyosarcomas and two neurofibromas. The results confirmed IMFT positivity for smooth muscle actin, desmin and cytokeratin in 78–89% cases, resulting in potential confusion with sarcomatoid carcinoma or leiomyosarcoma. In contrast, cytoplasmic anaplastic lymphoma kinase (ALK 1) staining was present in eight IMFT (89%), but was not seen in any other lesion examined. The ALK 1 staining was confirmed by fluorescence in situ hybridisation, with translocation of the ALK gene present in 15–60% tumour cells in four of six IMFT examined, but not in four cases of sarcomatoid carcinoma or three of leiomyosarcoma. In conclusion, ALK 1 staining may be of value in the distinction of vesical IMFT from morphologically similar entities, and often reflects ALK gene translocations in these lesions.