Clinical characteristics, molecular aberrations, treatments, and outcomes of malignant histiocytosis.

Malignant histiocytosis (MH) is an extremely rare neoplasm of the macrophage-dendritic cell lineage. We report the clinical characteristics, molecular aberrations, treatments, and outcomes of patients with MH seen at two referral centers from January 2000 to May 2023. We identified 43 patients with MH, of which 26 had histiocytic sarcoma (MH-H), 9 interdigitating dendritic cell sarcoma (MH-IDC), and 8 Langerhans cell sarcoma (MH-LC).

Utility of end of induction bone marrow biopsy and survival outcomes in acute promyelocytic leukemia treated with fixed-dose induction regimen.

Significant variations exist related to the end of induction practices in the management of Acute Promyelocytic Leukemia (APL). These variations include all-trans retinoic acid (ATRA)-arsenic trioxide (ATO) in fixed doses versus continuation until hematologic complete remission (CR) and performance versus omission of post-induction bone marrow biopsy to confirm morphological CR. A retrospective chart review was conducted of 61 patients (42 low/intermediate-risk and 19 high-risk) aged ≥ 18 years with newly diagnosed APL treated with fixed duration ATRA-ATO +/- cytoreduction at a tertiary medical center from December 2012 through March 2020.

Spectrum of second primary malignancies and cause-specific mortality in pediatric and adult langerhans cell histiocytosis.

With the advent of targeted therapeutics in Langerhans cell histiocytosis (LCH), there is a growing survivor population that might be at risk for late mortality from non-LCH causes, including second primary malignancies (SPMs). We undertook a large study using the Surveillance, Epidemiology, and End Results (SEER) database to evaluate the patterns of SPMs and cause-specific mortality among individuals with LCH (2000-2016) from the US. We found an increased risk of SPMs in the cohort (standardized incidence ratio [SIR] 2.

Utility of Single-Gene Testing in Cancer Specimens.

Molecular testing is now considered the standard of care to screen for disease, confirm the diagnosis, guide management, and use target therapy. Currently, several testing strategies are being used. One of the most common strategies is single-gene testing, which is often conducted for known mutations, such as BRAF in melanoma and EGFR in lung cancer.

IDH1 inhibitor-induced neutrophilic dermatosis in a patient with acute myeloid leukemia.

Ivosidenib is an oral inhibitor of mutant Isocitrate dehydrogenase 1 (IDH1). It is approved for treatment of patients with relapsed or refractory IDH1-mutated acute myeloid leukemia (AML) and patients with newly diagnosed IDH1-mutated AML who are 75 years or older or those who are ineligible to receive intensive chemotherapy. While generally well tolerated, differentiation syndrome has been reported in 15-20% of patients.

The Interpretation of Sequence Variants in Myeloid Neoplasms.

Objectives: To provide an overview of the challenges encountered during the interpretation of sequence variants detected by next-generation sequencing (NGS) in myeloid neoplasms, as well as the limitations of the technology with the goal of preventing the over- or undercalling of alterations that may have a significant effect on patient management.

Methods: Review of the peer-reviewed literature on the interpretation, reporting, and technical challenges of NGS assays for myeloid neoplasms.

Results: NGS has been integrated widely and rapidly into the standard evaluating of myeloid neoplasms.

Diagnostic utility of one-stop fusion gene panel to detect TFE3/TFEB gene rearrangement and amplification in renal cell carcinomas.

MiT family translocation renal cell carcinoma (MiT-RCC) harbors translocations involving the TFE3 or TFEB genes. RCC with TFEB amplification is also identified and is associated with a more aggressive clinical course. Accurate diagnosis of MiT-RCC is crucial for patient management.

Poroid adnexal skin tumors with YAP1 fusions exhibit similar histopathologic features: A series of six YAP1-rearranged adnexal skin tumors.

Background: Adnexal skin tumors are diagnostically challenging with few known molecular signatures. Recently, however, YAP1-MAML2 and YAP1-NUTM1 fusions were identified in poroid adnexal skin tumors.

Methods: Herein, we subjected eight poroid adnexal skin tumors (three poromas and five porocarcinomas) to fusion gene analysis by whole transcriptome sequencing and next-generation DNA sequencing analysis.

Cerebral Invasive Aspergillosis in a Case of Chronic Lymphocytic Leukemia with Bruton Tyrosine Kinase Inhibitor.

Bruton tyrosine kinase (BTK) inhibitors have become an important therapy for untreated and previously treated patients with chronic lymphocytic leukemia (CLL). Despite improved outcomes, rare adverse events, such as invasive fungal infections, have been reported with the use of first-generation BTK inhibitors. Invasive fungal infections carry a high morbidity and mortality risk.

Acute Myeloid Leukemia Case Harboring Unusual FLT3 Variant: Somatic vs Germline?

FLT3 mutations are considered a prognostic and predictive marker. Here we report on a patient with a rare FLT3 germline variant in the context of relapsed acute myeloid leukemia (AML). A female patient aged 57 years presented with AML with mutations in the IDH2, ASXL1, and DNMT3A genes.

Molecular Pathology of Colorectal Cancer.

Colorectal cancer (CRC) is the third most commonly diagnosed cancer. This review gives an overview of the current knowledge of molecular mechanisms of colorectal carcinogenesis and the role of molecular testing in the management of CRC. The majority of CRCs arise from precursor lesions such as adenoma, transforming to adenocarcinoma.

Clear cell papillary renal cell carcinoma: molecular profile and virtual karyotype.

Clear cell papillary renal cell carcinoma (CCP-RCC) is a recently recognized tumor that shares morphologic features of both clear cell renal cell carcinoma and papillary renal cell carcinoma but behaves in a more indolent fashion. To date, there is little molecular information available on CCP-RCC. DNA was extracted from formalin-fixed, paraffin-embedded tissue blocks of 22 cases of CCP-RCC at the University of Alabama at Birmingham.

Effects of Improved DNA Integrity by Punch From Tissue Blocks as Compared to Pinpoint Extraction From Unstained Slides on Next-Generation Sequencing Quality Metrics.

Objectives: To compare the effects of two methods of formalin-fixed paraffin-embedded (FFPE) tissue harvesting on DNA quality and next-generation sequencing (NGS) quality metrics.

Methods: DNA integrity number (DIN) and NGS quality metrics resulting from DNA extraction and sequencing of 199 sequential samples harvested via the Pinpoint Slide DNA Isolation System and the punch method were compared.

Results: DNA extracted from FFPE tissue punches had higher DIN than that extracted from Pinpoint samples (mean ± SD, 6.

Adamantinoma-Like Ewing Sarcoma of the Thyroid: A Case Report and Review of the Literature.

Currently considered a variant of Ewing sarcoma, adamantinoma-like Ewing sarcoma is a rare malignancy that shows classic Ewing sarcoma-associated gene fusions but also epithelial differentiation. Here we present the 6th reported case of adamantinoma-like Ewing sarcoma involving the thyroid gland. Sections of the thyroid tumor from a 20-year old woman showed sheets, lobules and trabeculae of primitive, uniform, small round blue cells that diffusely expressed pankeratin, p40 and CD99.

NUTM1-rearranged neoplasia: a multi-institution experience yields novel fusion partners and expands the histologic spectrum.

Poorly differentiated neoplasms lacking characteristic histopathologic features represent a significant challenge to the pathologist for diagnostic classification. Classically, NUT carcinoma (previously NUT midline carcinoma) is poorly differentiated but typically exhibits variable degrees of squamous differentiation. Diagnosis is genetically defined by NUTM1 rearrangement, usually with BRD4 as the fusion partner.

Spindle Epithelial Tumor with Thymus-Like Differentiation (SETTLE): A Next-Generation Sequencing Study.

Spindle epithelial tumor with thymus-like differentiation (SETTLE) is a malignant biphasic neoplasm of the thyroid or neck with propensity for late metastasis. Unlike synovial sarcoma, its main morphologic mimic, SETTLE lacks synovial sarcoma-associated translocations. A single case of SETTLE has shown a KRAS mutation but to date no comprehensive next generation sequencing studies of this rare neoplasm have been undertaken.

Malignant Ewing-Like Neoplasm With an EWSR1-KLF15 Fusion: At the Crossroads of a Myoepithelial Carcinoma and a Ewing-Like Sarcoma. A Case Report With Treatment Options.

We present a case of a malignant Ewing-like neoplasm of the parotid gland in a 20-year-old woman with an EWSR1-KLF15 gene fusion that presented with pulmonary metastasis. Despite the fact that the tumor was essentially immunohistochemically negative for keratins, p63, and p40, we interpret this neoplasm as an unusual form of a high-grade myoepithelial carcinoma based on its focal plasmacytoid cytology, chondromyxoid matrix, SOX10, S100 protein, and calponin expression, and the knowledge that the EWSR1-KLF15 gene fusion has, to date, only been identified in 2 tumors, both myoepithelial carcinomas of the kidney. We also present a cytogenetic analysis of this unusual tumor.

An Occult Malignancy Behind a Demyelinating Disease: POEMS Syndrome.

We report a case of a 38-year-old man presenting with bilateral lower extremity weakness and paresthesias that progressed during a 4-month period to severe polyneuropathy forcing the patient to be bed bound. Throughout his multiple hospitalizations, he was treated erroneously for chronic inflammatory demyelinating polyneuropathy, without significant improvement in his symptoms. In addition, he developed hepatosplenomegaly (organomegaly); endocrinopathies such as diabetes mellitus, central hypogonadism, and hypothyroidism; monoclonal spike evidenced in the serum electrophoresis; and hyperpigmentation of skin, altogether consistent with POEMS syndrome.

Is the routine microscopic examination of proximal and distal resection margins in colorectal cancer surgery justified?

Microscopic examination of the proximal and distal resection margins is part of the routine pathologic evaluation of colorectal surgical specimens removed for adenocarcinoma. Anastomotic donuts are frequently received and microscopically examined. We examined 594 specimens received over a period of 10 years and found only 3 cases of definitive direct involvement of a longitudinal margin by carcinoma.

Scolecobasidium granulomatous pneumonia and abscess - an emerging opportunistic fungal pathogen: a case report.

Scolecobasidium sp. are commensal soil and water thermophilic dematiaceous fungi. They are commonly isolated as contaminants from respiratory secretions due to their abundant presence in water supplies, but they are also rare yet emerging culprits producing severe opportunistic infections in immunocompromised individuals.