Clinical implications of additional chromosomal abnormalities in adult acute myeloid leukemia with inv (16)/t(16;16)/CBFB::MYH11.

OBJECTIVES: This study assesses the clinical significance of additional cytogenetic abnormalities (ACAs) and/or the deletion of 3'CBFB (3'CBFBdel) resulting in unbalanced CBFB::MYH11 fusion in acute myeloid leukemia (AML) with inv (16)/t(16;16)/CBFB::MYH11. METHODS: We retrospectively evaluated the clinicopathologic features of 47 adult de novo AML with inv (16)/t(16;16)/CBFB::MYH11 fusion. There were 44 balanced and 3 unbalanced CBFB::MYH11 fusions. Given the low frequency of unbalanced cases, the latter group was combined with 19 published cases (N = 22) for statistic and meta-analysis. RESULTS: Both balanced and unbalanced cases were characterized by frequent ACAs (56.5% and 72.7%, respectively), with +8, +22, and del(7q) as the most frequent abnormalities. The unbalanced group tends to be younger individuals (p = .04) and is associated with a lower remission rate (p = .02), although the median overall survival (OS) was not statistically different (p = .2868). In the balanced group, "ACA" subgroup had higher mortality (p = .013) and shorter OS (p = .011), and patients with relapsed disease had a significantly shorter OS (p = .0011). Cox multivariate regression analysis confirmed that ACAs and history of disease relapse are independent risk factors, irrespective of disease relapse status. In the combined cohort, cases with ACAs had shorter OS than those with "Sole" abnormality (p = .0109). CONCLUSIONS: ACAs are independent high-risk factors in adult AML with inv (16)/t(16;16)/CBFB::MYH11 fusion and should be integrated for risk stratification in this disease. Larger studies are needed to assess the clinical significance of the unbalanced CBFB::MYH11 fusion resulting from the 3'CBFBdel.

Poorly differentiated thyroid carcinoma of childhood and adolescence: a distinct entity characterized by DICER1 mutations.

Poorly differentiated thyroid carcinomas (PDTC) in young individuals are rare and their clinical and histopathologic features, genetic mechanisms, and outcomes remain largely unknown. Here, we report a detailed characterization of a series of six PDTC in patients ≤21 years old defined by Turin diagnostic criteria studied for mutations and gene fusions characteristic of thyroid cancer using targeted next-generation sequencing (NGS) and whole-exome sequencing (WES). All tumors had solid, insular, or trabecular growth pattern and high mitotic rate, and five out of six tumors showed tumor necrosis. Targeted NGS assay identified somatic mutations in the DICER1 gene in five of six (83%) tumors, all of which were "hotspot" mutations encoding the metal-ion binding sites of the RNase IIIb domain of DICER1. WES was performed in five cases which confirmed all hotspot mutations and detected two tumors with additional inactivating DICER1 alterations. Of these two, one was a germline pathogenic DICER1 variant and the other had loss of heterozygosity for DICER1. No other mutations or gene fusions characteristic of adult well-differentiated thyroid cancer and PDTC (BRAF, RAS, TERT, RET/PTC, and other) were detected. On follow-up, available for five patients, three patients died of disease 8-24 months after diagnosis, whereas two were alive with no disease. The results of our study demonstrate that childhood- and adolescent-onset PDTC are genetically distinct from adult-onset PDTC in that they are strongly associated with DICER1 mutations and may herald DICER1 syndrome in a minority. As such, all young persons with PDTC may benefit from genetic counseling. Furthermore, their clinically aggressive behavior contrasts sharply with the indolent nature of the great majority of thyroid tumors with DICER1 mutations reported to date.

Prognostic significance of copy number gains of MYC detected by fluorescence in situ hybridization in large B-cell lymphoma.

The MYC protooncogene plays a critical role in many cellular processes. MYC translocations are recurrent in large B-cell lymphomas (LBCLs) where they exhibit a negative effect on survival. Gain of MYC copies is also frequently identified; however, there is no consensus on the frequency and prognostic significance of MYC copy gains. We collected FISH data for MYC with reflex testing for BCL2 and BCL6 and IHC results at diagnosis for a cohort of 396 de novo and transformed LBCL cases and compared progression-free (PFS) and overall survival (OS) to determine the prognostic impact of extra MYC copies. The prevalence of cases with MYC copy number gain was 20.9%. PFS was shorter for patients with ≥5 MYC copies compared to controls (p = 0.0005, HR = 2.25). .MYC gain trended towards worse OS; patients with ≥7MYC copies had worse OS (p = 0.013), similar to patients with MYC translocations. We propose that MYC gain represents a dose-dependent prognostic factor for LBCLs.

Real world predictors of response and 24-month survival in high-grade TP53-mutated myeloid neoplasms.

Current therapies for high-grade TP53-mutated myeloid neoplasms (≥10% blasts) do not offer a meaningful survival benefit except allogeneic stem cell transplantation in the minority who achieve a complete response to first line therapy (CR1). To identify reliable pre-therapy predictors of complete response to first-line therapy (CR1) and outcomes, we assembled a cohort of 242 individuals with TP53-mutated myeloid neoplasms and ≥10% blasts with well-annotated clinical, molecular and pathology data. Key outcomes examined were CR1 & 24-month survival (OS24). In this elderly cohort (median age 68.2 years) with 74.0% receiving frontline non-intensive regimens (hypomethylating agents +/- venetoclax), the overall cohort CR1 rate was 25.6% (50/195). We additionally identified several pre-therapy factors predictive of inferior CR1 including male gender (P = 0.026), ≥2 autosomal monosomies (P < 0.001), -17/17p (P = 0.011), multi-hit TP53 allelic state (P < 0.001) and CUX1 co-alterations (P = 0.010). In univariable analysis of the entire cohort, inferior OS24 was predicated by ≥2 monosomies (P = 0.004), TP53 VAF > 25% (P = 0.002), TP53 splice junction mutations (P = 0.007) and antecedent treated myeloid neoplasm (P = 0.001). In addition, mutations/deletions in CUX1, U2AF1, EZH2, TET2, CBL, or KRAS ('EPI6' signature) predicted inferior OS24 (HR = 2.0 [1.5-2.8]; P < 0.0001). In a subgroup analysis of HMA +/-Ven treated individuals (N = 144), TP53 VAF and monosomies did not impact OS24. A risk score for HMA +/-Ven treated individuals incorporating three pre-therapy predictors including TP53 splice junction mutations, EPI6 and antecedent treated myeloid neoplasm stratified 3 prognostic distinct groups: intermediate, intermediate-poor, and poor with significantly different median (12.8, 6.0, 4.3 months) and 24-month (20.9%, 5.7%, 0.5%) survival (P < 0.0001). For the first time, in a seemingly monolithic high-risk cohort, our data identifies several baseline factors that predict response and 24-month survival.

Many faces of SF3B1-mutated myeloid neoplasms: concurrent mutational profiles contribute to the diverse clinical and morphologic features.

Splicing factor SF3B1 mutation occurs in 20-30% of myelodysplastic syndrome (MDS) and myelodysplasia/myeloproliferative neoplasm (MDS/MPN), particularly those with ring sideroblasts (RS), and rarely in acute myeloid leukemia (AML). In this study, we performed a comprehensive evaluation of 77 SF3B1-mutated myeloid neoplasms (45 MDS, 18 MDS/MPN, 13 AML, and 1 MPN), including their clinical presentations, morphologic features, cytogenetic studies, and targeted next-generation sequencing. Our study demonstrated that concurrent gene mutations were very different in SF3B1-mutated MDS, MDS/MPN, and AML. MDS cases were frequently characterized by either sole SF3B1 mutation or in combination with TET2 mutation. Acquiring additional mutations in transcription factors, such as RUNX1 and GATA2, were associated with increased blasts and progression to AML in patients with MDS or MDS/MPN. Our study also demonstrated that SF3B1-mutated MDS/MPN was not only associated with thrombocytosis (5/18, 27.7%), defined by the current WHO classification as MDS/MPN-RS-T, but also associated with neutrophilia (6/18, 33.3%), monocytosis (6/18, 33.3%), and mastocytosis (1/18, 5.6%). Our results indicate that although SF3B1-mutated myeloid neoplasms in general have a good prognosis, evaluation of the concurrent gene mutational profile is important for risk stratification. In addition, our study, in combination with other published data, suggests that the category of MDS/MPN-RS-T in the current WHO classification could be expanded to include SF3B1-mutated MDS/MPN-RS with peripheral leukocytosis such as neutrophilia and monocytosis.

Distinctive Flow Cytometric and Mutational Profile of Acute Myeloid Leukemia With t(8;16)(p11;p13) Translocation.

OBJECTIVES: Acute myeloid leukemia (AML) with t(8;16)(p11;p13) abnormalities is a rare, aggressive, and diagnostically challenging subtype that results in KAT6A-CREBBP gene fusion. METHODS: To investigate their immunophenotype and genomic features, we identified 5 cases of AML with t(8;16) through a retrospective review of the databases at Northwestern Memorial Hospital in Chicago, IL, and Washington University Medical Center, in St Louis, MO. RESULTS: In all, 4 of 5 cases were therapy related and 1 was possibly therapy related. The leukemic blasts showed distinctive features, including bright CD45 expression and remarkably high side scatter that overlapped with maturing myeloid elements, making the blasts difficult to identify on initial examination. They were positive for CD13, CD33, and CD64 and negative for CD34 and CD117. Next-generation sequencing profiling of 4 cases revealed pathogenic ASXL1 (2 cases), FLT3-tyrosine kinase domain (TKD) mutations (2 cases), and other pathogenic mutations. In 3 patients, t(8;16) was the sole cytogenetic abnormality; additional aberrations were found in 2 patients. Single nucleotide polymorphism microarray revealed 1 case with 7q deletion as a secondary clone. CONCLUSIONS: Our data highlight the distinctive immunophenotypic profile of AML with t(8;16), which, along with its unique morphology, often presents a diagnostic challenge. We showed that mutations of either ASXL1 or FLT3-TKD are seen in most cases of this leukemia.

Utility of Flow Cytometry of Bronchoalveolar Lavage in the Diagnosis of T and NK Cell Malignancies in Critically Ill Patients.

OBJECTIVE: The value of bronchoalveolar lavage (BAL) in the diagnosis of pulmonary diseases of diverse etiologies is widely accepted. Cytospin and cell-block preparations for cytomorphological (CM) evaluation and for immunohistochemical studies are the standard method to evaluate BAL, though it may be time-consuming. Flow cytometric (FC) evaluation, on the other hand, has a short turnaround time, and is a useful methodology to differentiate reactive processes from hematological neoplasms, or detect a small aberrant population in an inflammatory background. BAL specimens provide an excellent source for FC studies. CASE REPORTS: We describe two cases of critically ill patients with no history of hematolymphoid neoplasms, who presented with non-specific symptoms. Abnormal pulmonary imaging studies prompted bronchoscopic evaluation and collection of BAL during the initial evaluation. FC analysis of the BAL fluid aided to the early diagnosis of aggressive NK cell leukemia and adult T cell leukemia/lymphoma, respectively. CONCLUSIONS: Flow cytometric immunophenotyping in addition to the CM assessment increases the diagnostic value and provides timely diagnosis from BAL specimens, which is especially important for critically ill patients.

Tryptase Positivity in Chronic Myeloid Leukemia With Marked Basophilia.

Chronic myeloid leukemia (CML) is the most common chronic myeloproliferative disorder, which was the first to be described and understood at a molecular level. Marked basophilia can be seen in CML and other neoplastic and reactive processes. Tryptase is a serine protease that is mainly expressed in mast cells, whereas basophils express only trace amounts of the enzyme. Therefore, it has always been regarded as a specific marker for mast cells. We report a case of a 41-year-old male who had been diagnosed with CML eight years ago, and, interestingly, his most recent bone marrow biopsy demonstrated an accelerated phase of the disease with a significant increase of basophils count. These basophils were immunoreactive with tryptase along with CD123. In the literature, this phenomenon of tryptase immunoreactivity by basophils has been described in association with CML, primary myelofibrosis, and myelodysplastic syndrome. Therefore, our finding supports these data and suggests that tryptase should not be regarded as a specific marker for mast cells when approaching various myeloid neoplasms including CML.

Immunophenotypic Variations in Mantle Cell Lymphoma and Their Impact on Clinical Behavior and Outcome.

CONTEXT.­: Immunophenotypic variations in mantle cell lymphoma (MCL) from the classic CD5+/CD10-/CD23-/FMC-7+ immunophenotype have been reported in the literature, but correlation with clinical behavior and outcome has not been fully studied. OBJECTIVE.­: To investigate clinicopathologic and prognostic differences between immunophenotypically aberrant MCL and immunophenotypically typical MCL. DESIGN.­: We evaluated differences in clinical presentation, laboratory parameters, prognostic indices, response to initial treatment, and progression-free and overall survival between patients with aberrant MCL and patients with immunophenotypically typical MCL. RESULTS.­: There were 158 patients with newly diagnosed cyclin D1 or t(11;14)(q13;q32)+ MCL identified in the original search, of which, 29 patients (18%) showed immunophenotypic aberrancies, with CD23 coexpression being the most common. When compared with 33 randomly selected patients with immunophenotypically typical MCL, statistically significant differences were seen in white blood cell counts ( P = .02), in the presence of absolute lymphocytosis ( P = .03), in the MCL International Prognostic Index score ( P = .02), and in response to initial treatment ( P = .04). The "immunophenotypic status" of the MCL was the only independent factor associated with response to treatment ( P = .05), but not with the MCL International Prognostic Index score, absolute lymphocytosis, or white blood cell count. No significant differences were seen for progression-free or overall survival. CONCLUSIONS.­: Immunophenotypic variations in MCL are associated with differences in clinical presentation and response to therapy when compared with immunophenotypically typical MCL. However, with current intensive frontline immunochemotherapy, immunophenotypic aberrations do not appear to affect progression-free or overall survival.

Lambda Immunoglobulin Light Chain Restricted B Cells in the Ascitic Fluid in Association with Terminal Ileal Florid Follicular Hyperplasia.

Distinguishing reactive changes from neoplastic processes during lymphoid tissue evaluation is oftentimes difficult. Ancillary studies, such as flow cytometry, may aid the diagnosis by demonstrating monotypic or polytypic light chain expression on the B cells. The detection of immunoglobulin light chain restricted B cell population is considered a surrogate marker of clonality, which can be confirmed by molecular assays. In general, the presence of a monotypic B cell population in the ascitic fluid is considered lymphomatous involvement rather than a reactive condition. We describe a young, previously healthy male patient who developed ascites with a lambda light chain restricted B cell population. Further investigation revealed florid follicular hyperplasia, histologically mimicking diffuse large B cell lymphoma, in the terminal ileum. Follicular hyperplasia in the gastrointestinal tract with lambda light chain restricted B cells has been recently described in the pediatric population. Importantly, our case demonstrates that such entity can occur in older age groups. This recognition could prevent misdiagnosis and unnecessary treatment in similar cases.

Are micromegakaryocytes specific for refractory cytopenia of childhood (RCC)? A study of 38 pediatric patients with thrombocytopenia unrelated to RCC.

BACKGROUND: Micromegakaryocytes (microMKs) are considered the most reliable dysplastic feature for myelodysplastic syndrome (MDS), particularly refractory cytopenia of childhood (RCC); there is no minimal threshold for the diagnosis of RCC. Since most RCC patients present with thrombocytopenia, the presence of microMKs should raise concern for MDS/RCC. This study attempted to investigate the prevalence of microMKs and associated marrow fibrosis in patients with thrombocytopenia unrelated to MDS/RCC and the need for establishing a threshold for microMKs for the diagnosis of MDS/RCC. DESIGN: Bone marrow biopsies of pediatric patients with thrombocytopenia unrelated to RCC were examined for microMKs and fibrosis by CD61 immunohistochemical and reticulin stains respectively. RESULT: Thirty eight patients (1-18 years old) were included: 33 immune thrombocytopenia (ITP), 3 chronic thrombocytopenia, and 2 inherited macrothrombocytopenia. Fourteen cases (37%) had microMKs; four cases showed increased marrow fibrosis associated with microMKs (two had ITP and two had macrothrombocytopenia). All patients are alive and none developed MDS (follow up: 3months to 4 years). CONCLUSION: MicroMKs can be seen in pediatric patients with thrombocytopenia unrelated to RCC. Hence the mere presence of microMKs is insufficient for the diagnosis of RCC in the pediatric population, and a quantitative threshold needs to be established.

Childhood nodal marginal zone lymphoma with unusual clinicopathologic and cytogenetic features for the pediatric variant: a case report.

Nodal marginal zone lymphoma (NMZL) is a B-cell lymphoma that shares morphologic and immunophenotypic features with extranodal and splenic marginal zone lymphomas but lacks extranodal or splenic involvement at presentation. NMZL occurs mostly in adults with no sex predilection, at advanced stage (III or IV), with frequent relapses and a high incidence of tumoral genetic abnormalities including trisomies 3 and 18 and gain of 7q. Pediatric NMZL, however, is a rare but distinct variant of NMZL with characteristic features including male predominance, asymptomatic and localized (stage I) disease, low relapse rates with excellent outcomes, and a lower incidence of essentially similar genetic aberrations compared to adult NMZL. Here we describe a unique case of childhood NMZL with unusual clinicopathologic features for the pediatric variant including generalized lymphadenopathy, high-stage disease with persistence after therapy, unusual immunophenotype (CD5, CD23, and BCL6 positive), and unique chromosomal abnormalities including monosomy 20 and add(10)(p11.2).

Primary splenic angiosarcoma associated with anemia, leukocytosis and thrombocytopenia.

Primary angiosarcoma of the spleen is a rare neoplasm arising from endothelial cells. It is an aggressive neoplasm with a poor prognosis. We report a case of 61-year-old Caucasian man who presented with shortness of breath, anemia, leukocytosis, and thrombocytopenia. Ultrasound Sonogram (US) and Computed Tomography (CT) scans revealed a massively enlarged spleen with numerous enhancing hypodense lesions. The spleen was adherent to the omentum, retroperitoneum, and tail of the pancreas. Image-guided Fine Needle Aspiration (FNA) revealed an atypical spindle cell lesion. Resection of the spleen and attached tail of pancreas was performed. Histological examination and immunohistochemical studies revealed a diffuse vascular malignant neoplasm with features of angiosarcoma. The patient appeared disease free after resection. He died within 5 months of unknown etiology.

Implementation of a quality improvement program to improve sweat test performance in a pediatric hospital.

CONTEXT: All positive screening of newborns for cystic fibrosis using the dried blood spot 2-tiered immunoreactive trypsinogen/DNA method requires subsequent sweat chloride testing for confirmation. Obtaining an adequate volume of sweat to measure chloride is a challenge for many cystic fibrosis centers across the nation. The standard for patients older than 3 months is less than 5% quantity not sufficient (QNS) and for patients 3 months or younger is less than 10% QNS. OBJECTIVE: To set up a quality improvement (QI) program for sweat testing to improve QNS rates using the Wescor Macroduct (Wescor, Inc, Logan, Utah) method at Texas Children's Hospital's laboratory, Houston, Texas. DESIGN: Single-center study. RESULTS: Quantity not sufficient rates were evaluated for 4 months before and 8 months after implementation of the QI program for patients aged 3 months or younger and those older than 3 months. The QI program included changes in technician training, service, site of collection, mode of collection, weekly review, and forms to screen patients for medications that may alter sweat production. A marked improvement was observed in the rates of QNS, which declined considerably from 16.7% to 8.5% (≤3 months old) and from 9.3% to 2.2% (>3 months old) after implementation of the QI initiative in both age categories. CONCLUSION: This report demonstrates the effectiveness of the QI program in significantly improving QNS rates in sweat chloride testing in a pediatric hospital.

Post cardiac transplantation T-cell lymphoproliferative disorder presenting as a solitary lung nodule.

Post-transplantation lymphoproliferative disorder (PTLD) is an infrequent, but serious complication of solid organ and bone marrow transplantations. The vast majority of the cases are of B-cell origin and usually associated with Epstein-Barr virus (EBV) infection. The non-B (T and NK cell) PTLDs account for up to 14% of the PTLD cases in Western countries. We report a case of a 66-year-old man who received an orthotopic heart transplant for cardiomyopathy 7 years prior to presentation. He was referred to our institution with a hypermetabolic solitary right lower lobe lung nodule with an SUV of 9.2 on PET scan. The combined histomorphological and immunohistochemical pattern was most consistent with monomorphic PTLD, peripheral T-cell lymphoma with angioimmunoblastic features. Molecular studies showed clonal T-cell gamma receptor gene rearrangement. Primary pulmonary involvement of T-cell PTLD is extremely rare. This is the third reported case of T-cell PTLD after cardiac transplantation, primarily involving the lung. Further, studies will be required to determine the appropriate treatment and prognosis of this rare entity.

Neoplastic and nonneoplastic ovarian masses: Diagnosis on cytology.

OBJECTIVE: To evaluate the role of fine needle aspiration cytology (FNAC) in the distinction between neoplastic and nonneoplastic ovarian masses. MATERIALS AND METHODS: One hundred and twenty patients with ovarian masses were studied. After detailed history and clinical examination, ultrasound (USG)-guided FNAC was performed in 92 clinical benign cases while FNAC and/or imprints of surgically resected ovarian masses was performed in 28 clinically suspected malignant cases. The smears were stained with Papanicolaou stain and histopathological sections were stained with hematoxylin and eosin stain with inclusion of special stain whenever required. Serum ß-human chorionic gonadotrophin and α-fetoprotein estimations were carried out in cytologically diagnosed germ cell tumors. RESULTS: The overall sensitivity, specificity and diagnostic accuracy of FNAC in diagnosing various ovarian masses were 79.2%, 90.6% and 89.9%, respectively. CONCLUSIONS: The clinical examination, pelvic ultrasound and FNAC were complementary and none of the methods was, in itself, diagnostic. However, USG-guided FNAC was found to be a fairly specific and accurate technique and should be employed as a routine, especially in young females with clinically benign ovarian lesions. The reasons for false diagnosis and limitations of USG and FNAC have been analyzed.