Null Immunophenotype Research Articles

Comprehensive genomic profiling in multiple cancer types: A comparative analysis of the National Biobank Consortium of Taiwan and clinical practice cohorts

BackgroundThis retrospective study analyzed tumor tissue profiling data to assess the potential of comprehensive genomic profiling (CGP) for patient care across diverse solid tumors. Material and methodsPatients with newly diagnosed or recurrent stage IIIB or IV lung adenocarcinoma with a null immunophenotype and esophageal, gastric, pancreatic, or bile duct cancer between January 2020 and July 2023 at two medical centers in Taiwan were included. One cohort was a part of the National Biobank Consortium of Taiwan project, whereas the other consisted of patients undergoing routine clinical practice. Tumor samples were subjected to CGP using FoundationOne®CDx, with therapeutic implications determined using OncoKB classification. ResultsFoundationOne®CDx testing of 574 patients was successful in 456 (79.4%) patients. Clinically actionable genomic alterations were detected in 21.1% (96/456) of the patients, including 17.5%, 2.9%, and 0.7% of patients with evidence levels 1, 2, and 3, respectively. Lung adenocarcinoma accounted for the largest proportion of samples with at least one actionable gene alteration (63.2%), followed by bile duct (26.9%), gastric (17.6%), esophageal (4.0%), and pancreatic (3.1%) cancers. Based on CGP results, 43 patients (9.4%) received matched targeted therapy. The median overall survival of patients who received matched therapy or not was 26.1 months (95% confidence interval (CI), 16.7–35.5 months) and 10.6 months (95% CI, 8.1–13.1 months; hazard ratio, 0.28, 95% CI, 0.14–0.55, p < 0.001), respectively. ConclusionsThis study provides comprehensive insights into the genomic profiles of diverse cancers in Taiwan, highlighting the crucial role of CGP in identifying actionable genomic alterations and guiding effective therapeutic strategies in real-world practice.

Real-world insights from comprehensive genomic profiling across multiple cancer types.

106 Background: This retrospective study was conducted to analyze tumor tissue profiling data to assess the potential of applying comprehensive genomic profiling (CGP) in patient care across diverse solid tumors. Methods: Patients with newly diagnosed or recurrent stage IIIB or IV lung adenocarcinoma with the null immunophenotype, esophageal, gastric, pancreatic, or bile duct cancer between January 2020 and July 2023 at two medical centers in Taiwan were included in the National Biobank Consortium of Taiwan project. The tumor samples were subjected to CGP using FoundationOneCDx, with therapeutic implications determined using OncoKB classification. Results: FoundationOneCDx testing of 574 patients was successful in 456 (79.4%) patients. Clinically actionable genomic alterations were detected in 21.1% (96/456) of the patients, including 17.5%, 2.9%, and 0.7% of patients at evidence levels 1, 2, and 3, respectively. Lung adenocarcinoma accounted for the largest proportion of samples with at least one actionable gene alteration (63.2%), followed by bile duct (26.9%), gastric (17.6%), esophageal (4.0%), and pancreatic (3.1%) cancer. Based on the CGP results, 43 patients (9.4%) received matched targeted therapy. The median overall survival of patients who received matched therapy or not was 26.1 months (95% confidence interval (CI), 16.7–35.5 months) and 10.6 months (95% CI, 8.1–13.1 months; hazard ratio, 0.28, 95% CI, 0.14–0.55, p &lt; 0.001), respectively. Conclusions: This study provides comprehensive insights into genomic profiling across diverse cancers in Taiwan, highlighting the crucial role of CGP in identifying actionable genomic alterations and guiding effective therapeutic strategies in real-world practice.

Novel EWSR1::GFI1B gene fusion in angiofibroma of soft tissue.

Angiofibroma of soft tissue is a benign soft tissue tumour characterised by bland spindle cells and a distinct branching vascular network. The majority of soft tissue angiofibromas harbour AHRR::NCOA2 gene fusions. Here we present three cases of EWSR1::GFI1B-fused soft tissue tumours that are morphologically most reminiscent of soft tissue angiofibroma. All three cases presented in male patients with an age range of 35-78 years (median = 54 years). Two cases presented as subcutaneous nodules on the trunk (posterior neck and chest wall); one was an intramuscular foot mass. The tumours were unencapsulated nodules with infiltrative margins ranging from 2.2 to 3.4 cm in greatest dimension. Histologically, the tumours contained uniformly bland fibroblastic spindle cells with ovoid to fusiform nuclei and delicate cytoplasmic processes embedded in a myxoid to myxocollagenous stroma. All three cases were characterised by a thin-walled, branching vascular network evenly distributed throughout the tumour. Overt cytological atypia or conspicuous mitotic activity was absent. The spindle cells had an essentially null immunophenotype. By targeted RNA sequencing, an in-frame gene fusion between EWSR1 exons 1-7 and GFI1B exons 6-11 or 7-11 was detected in all three cases. The tumours were marginally excised. For all three cases, there were no documented local recurrence or distant metastases during a limited follow-up period of 6-10 months. We propose that EWSR1::GFI1B may represent a novel fusion variant of soft tissue angiofibroma.

Primary Effusion Lymphoma with Extracavitary Presentation and A T-Cell Immunophenotype: A Potential Diagnostic Pitfall

<p class=MsoListParagraph style=margin:0in;margin-bottom:.0001pt;mso-add-space: auto;text-align:justify;text-indent:0in;line-height:normal;mso-list:l0 level1 lfo1; mso-mirror-indents:yes> 1. Abstract <p class=MsoNormalCxSpMiddle style=margin-bottom:0in;margin-bottom:.0001pt; mso-add-space:auto;text-align:justify;line-height:normal;mso-mirror-indents: yes> Primary Effusion Lymphoma (PEL) is a unique immunodeficiency-associated malignancy that requires infection with Kaposi sarcoma herpesvirus/human herpesvirus 8 (KSHV/HHV8). Although thought to arise from mature B-lymphocytes, PEL typically has a null Immunophenotype but can very rarely show lineage specific aberrancies, including aberrant T-cell markers. Here we present one such case of PEL where aberrant T-cell markers led to a misdiagnosis of peripheral T-cell lymphoma. We performed a review of the literature to identify similar cases of PEL with strong T-cell antigen expression. Most cases occurred in men who were HIV positive or otherwise immunodeficient. Many were EBV positive. Rare cases demonstrated T-cell receptor gene rearrangements. Postulated theories for the cause of disordered differentiation include immunodeficiency and/or EBV infection. The expression of T-cell antigens on PELs may be a source for error in diagnosis and awareness of this correlation is of practical diagnostic relevance. <p class=MsoListParagraph style=margin:0in;margin-bottom:.0001pt;mso-add-space: auto;text-align:justify;text-indent:0in;line-height:normal;mso-list:l0 level1 lfo1; mso-mirror-indents:yes> 2. Keywords: <span style=font-size:10.0pt;font-family: times= new= roman,serif;color:black;mso-themecolor:text1=> Body Cavity Lymphoma; Effusion Lymphoma; Extracavitary Primary Effusion Lymphoma; KSHV/HHV8; PEL; Primary Effusion Lymphoma; T-Cell Primary Effusion Lymphoma

MTE02.01 Update on WHO Classification and Staging of Lung Cancer

The most significant changes in the 2015 WHO classification of the lung tumors include classification criteria for small biopsy and cytology specimens, use of immunohistochemistry, integration of molecular testing, adoption of the IASLC/ATS/ERS adenocarcinoma classification and a strict definition of large cell carcinoma limited to surgical resection specimens only. 1,2 Tumors that show unequivocal morphology of adenocarcinoma or squamous cell carcinoma on a small specimen should be diagnosed without immunohistochemistry. Immunohistochemical work up of poorly differentiated tumors should be limited to TTF-1and p40/p63, while neuroendocrine markers should be used only if morphologically indicated. This approach should reduce the diagnosis of NSCC, NOS to less than 5% and preserve tissue for molecular testing. 1,2 Major changes in the adenocarcinoma classification for resected specimens include addition of adenocarcinoma in situ (AIS) to preinvasive group that already includes atypical adenomatous hyperplasia. Minimally invasive adenocarcinoma (MIA) defined as a solitary, lepidic predominant adenocarcinoma presenting measuring in gross size 3 cm or less and with invasion of ≤ 5 mm was added as a new category. These tumors are also recognized by the 8th edition of the AJCC staging of lung cancer and include Tis(adenocarcinoma) and T1a-mi. T stage of non-mucinous lepidic predominant adenocarcinomas is based on the microscopic size of invasion, but gross size should be recorded in the pathology reports. Multifocal ground glass opacities/lung nodules most frequently present as MIAs and should be classified by the T category of the lesion with the highest T along with the number of lesions (#) or simply (m) for multiple indicated in parentheses, and with a single N and M category that applies to all of the multiple tumor foci. This approach should be applied to grossly or microscopically identified lesions occurring in the same or in different ipsilateral or contralateral lobes.3 For non-lepidic adenocarcinoma T stage is determined by gross size in 1.0 cm increments as each size subgroup carries prognostic significance. Former mucinous BAC are reclassified as invasive mucinous adenocarcinoma, excluding tumors that meet criteria for AIS or MIA. Signet ring and clear cell carcinomas are considered to represent cytologic variants rather than specific subtypes. Invasive adenocarcinomas should be subtyped by semi-quantitatively estimating the percentage of the various subtypes in 5% increments. 1,2 Reproducibility for lung adenocarcinoma predominant subtypes among pulmonary pathologists was good to moderate (κ-values 0.44 to 0.72).4 For untrained pathologists, κ-values were lower ranging from 0.38 to 0.47, but these improved after a training session and particularly for individual reviewer. 5 The 2015 WHO classification defines large cell carcinomas based on morphology, as carcinomas without morphologic evidence of glandular, squamous or neuroendocrine differentiation, and also based on null immunophenotype and genotype. 1This change in definition reflect what was already happening in the pathology practice. According to National Cancer Institute (NCI) Surveillance Epidemiology and End Results registry the diagnosis of large cell carcinoma started to decline about the time that TTF-1 was introduced into clinical diagnosis. 6 Travis WD, Brambilla E, Burke AP, Marx A, Nicholson AG. WHO Classification of Tumours of the Lung, Pleura, Thymus and Heart. Lyon: International Agency for Research on Cancer, 2015. Travis WD. Et al. The 2015 World Health Organization Classification of Lung Tumors Impact of Genetic, Clinical and Radiologic Advances Since the 2004 Classification. J Thorac Oncol 2015; 10 (9); 1243-1260 Frank C. Detterbeck, MD et al. The IASLC Lung Cancer Staging Project: Summary of Proposals for Revisions of the Classification of Lung Cancers with Multiple Pulmonary Sites of Involvement in the Forthcoming Eighth Edition of the TNM Classification . J Thorac Oncol 2016;11(5): 639-650 Thunnissen E, Beasley MB, Borczuk AC, et al. Reproducibility of histopathological subtypes and invasion in pulmonary adenocarcinoma. An international interobserver study. Mod Pathol 2012;25:1574–1583. Warth A, Cortis J, Fink L, et al.; Pulmonary Pathology Working Group of the German Society of Pathology. Training increases concordance in classifying pulmonary adenocarcinomas according to the novel IASLC/ ATS/ERS classification. Virchows Arch 2012;461:185–193. Lewis DR, Check DP, Caporaso NE, Travis WD, Devesa SS. US lung cancer trends by histologic type. Cancer 2014;120:2883–2892. lung carcinoma- WHO classification- staging

Molecular dissection of large cell carcinomas of the lung with null immunophenotype

The aim of this study was to subcategorise large cell carcinoma (LCC) with null immunophenotype according to the World Health Organization (WHO) Classification of 2015 into the existing groups of adenocarcinoma and squamous cell carcinoma by further molecular genetic analysis. Lineage-specific molecular alterations of these tumours could depict additional therapeutic approaches. We analysed a cohort of 35 LCC diagnosed according to the 2004 WHO classification and reclassified them according to the criteria of the 2015 WHO classification. Subsequently, tumours with a null immunophenotype were analysed by targeted next generation sequencing (42 marker genes including TP53, EGFR, KRAS, STK11 and SMARC4A) and fluorescence in situ hybridisation (ROS1, ALK). By applying the criteria of the 2015 WHO classification and subsequent molecular subtyping we could show that out of 35 previously diagnosed LCC, 16 cases could be reclassified into specific NSCLC subtypes using immunohistochemistry. Additionally, based on their mutational pattern, eight of the remaining 19 cases with null immunophenotype could be assigned as 'favour adenocarcinoma'. We demonstrate that molecular subtyping is helpful to further categorise LCC with null immunophenotype. Our findings argue for an algorithm including stratified molecular analysis of all respective cases.

Anaplastic Large Cell Lymphomas: A Study of 75 Pediatric Patients

In this article, we describe the morphologic and immunophenotypic features of 75 cases of pediatric anaplastic large cell lymphoma (ALCL). According to the World Health Organization classification, 49 cases were common subtype ALCL, and respectively, 3, 6, and 17 cases were small cell, lymphohistiocytic, or mixed histologic variants. Anaplastic lymphoma kinase positivity was detected in 90.7% of the tumors and, using a panel of 9 T-cell surface markers, 88% could be assigned to the T-cell lineage. A molecular analysis for the T-cell receptor gamma (TCR- gamma) and the heavy chain of the immunoglobulin H rearrangements was performed on 6/9 ALCLs with a null immunophenotype, and a TCR clonal pattern was detected in 5/6 cases. In addition, 94.1% were immunoreactive for 1 or more cytotoxic proteins (Tia1, granzyme B, or perforin), and 15% expressed CD56. Clusterin, CD83, and Pax5, respectively, expressed in 91.3%, 1.7%, and 0% of the ALCLs, were useful biomarkers for the differential diagnosis with Hodgkin's lymphomas.

High-Risk Human Papillomavirus Affects Prognosis in Patients With Surgically Treated Oropharyngeal Squamous Cell Carcinoma

Human papillomavirus (HPV) DNA tumors actively integrating the E6 and E7 oncogenes have a distinct biologic behavior resulting in a more favorable prognosis. To which extent the viral integration by itself, and/or the associated wild-type (wt) TP53 status, and/or a functional p16 contribute to prognosis is unclear. To clarify how the presence of high-risk (HR) -HPV, TP53, and p16INK4a status interact with clinical outcome, we considered a retrospective series of 90 consecutive oropharyngeal cancer patients treated primarily with surgery. Seventeen (19%) patients showed integrated HPV 16 DNA (HPV positive), wt TP53 in all but two patients, normal p16INK4a in 15 assessable patients, and p16 expression in all 17 patients. Thirty-five patients (39%), two of whom were HPV positive, harbored TP53 mutations. p16INK4a deletion and p16 null immunophenotype occurred in 28 and 58 patients, respectively, and was similarly distributed in both patients with mutated TP53 (48% and 82%, respectively) and in patients with wt TP53 (46% and 77%, respectively). Statistical analysis showed that HPV-positive status significantly affects all investigated end points: overall survival (P = .0018), incidence of tumor relapse (P = .0371), and second tumor (P = .0152), whereas TP53 and p16INK4a status and p16 expression were not prognostic by themselves. Our molecular and clinical results are in agreement with previous findings but provide additional information into the biologic mechanisms involved in HR-HPV oropharyngeal cancer in comparison to HPV-negative tumors. According to the reduced risk of relapse and second tumors associated with HR-HPV positivity of oropharyngeal cancer, the therapeutic strategy and follow-up procedures should be reviewed.

An immunohistochemical analysis of reedsternberg-like cells in posttransplantation lymphoproliferative disorders: The possible pathogenetic relationship to Reed-Sternberg cells in Hodgkin's disease and reedsternberg-like cells in non-Hodgkin's lymphomas and reactive conditions

The aim of this study was to assess the incidence and immunophenotype of Reed-Sternberg-like (R-S-like) cells in the setting of posttransplantation lymphoproliferative disorders (PTLD). Twenty-eight formalin-fixed, paraffin-embedded cases (17 renal and 11 heart/heart-lung PTLDS) were analyzed for the presence of typical binucleate cells with inclusionlike nucleoli—the Reed-Sternberg phenotype. An immunohistochemical evaluation for the following markers was performed: CD3, CD20, CD79a, CD15, CD30, CD45, EBVLMP-1, and vimentin. Monoclonality was assessed by staining for light chain restriction. Eleven cases contained R-S-like cells (9 renal and 2 heart/heart-lung PTLD). All 11 cases were positive for CD45 (LCA), EBV-LMP-1, and vimentin. Ten of 11 cases were CD20/CD79a positive, one case being of a null immunophenotype. Nine cases expressed CD30, whereas 0 of 11 were positive for CD15. In nine cases, expression of both kappa and lambda light chains was present; the remaining two cases failed to express either light chain. This study shows that the R-S-like cells encountered in PTLD have an activated B cell immunophenotype, are invariably EBV-LMP-1 positive, are often CD30 positive, and are CD15 negative. This latter immunophenotypic feature separates R-S-like cells from the R-S cells seen in Hodgkin's disease. The strong staining for EBV-LMP-1 in R-S-like cells also indicates a strong association between EBV-LMP and the R-S morphological phenotype in the context of PTLDs.

Cytogenetics adds independent prognostic information in adults with acute lymphoblastic leukaemia on MRC trial UKALL XA. MRC Adult Leukaemia Working Party.

Cytogenetic classification of 350 adults with acute lymphoblastic leukaemia on MRC UKALL XA trial showed the following statistically significant associations: t(9;22) (11%) increased with increasing age and leucocyte counts (WBC) and most had a C/pre-B immunophenotype. t(4;11) (3%) was associated with higher WBCs, increasing age and null immunophenotype. Other abnormalities of 11q (abn11q) (4%) were associated with male sex and T-cell ALL. High hyperdiploidy (7%) and abn9p (5%) decreased with increasing WBC. High hyperdiploid patients were younger and tended to have C/pre-B ALL. Triploidy/tetraploidy (3%) decreased and pseudodiploidy (11%) increased with increasing WBC. Cytogenetic classification was prognostically important (chi-square for heterogeneity of classification = 53.56; P < 0.0001) and added significance to age, sex and WBC. A poor prognosis for patients classed as t(9;22) (13% disease-free survival at 3 years), as t(4;11) 24% at 3 years) and hypodiploid (11% at 3 years), and good prognosis for abn12p (4% of subjects) and high hyperdiploidy (74% and 59% at 3 years respectively) were statistically significant, but the 54% 3-year disease-free survival for patients with t(1;19) was not. The prognosis of patients classed as t(9;22) was independent of other single variables. Abn12p, abnormalities of 11q (including t(4;11) cases) and hypodiploidy added prognostic significance to all other variables combined.