Publications by authors named "Joel Lefferts"

Article Synopsis
  • Poorly differentiated chordoma is a rare and aggressive type of tumor usually found in young patients, mainly at the skull base and cervical spine.
  • A case study of a 60-year-old patient initially misdiagnosed with osteoarthritis revealed complex tumor characteristics that led to reconsideration of its diagnosis.
  • The importance of accurate immunohistochemical testing, specifically for brachyury, is emphasized for correctly diagnosing this uncommon tumor and for understanding its unique molecular profile, which could aid in future analyses.
View Article and Find Full Text PDF
Article Synopsis
  • Mesenchymal neoplasms in the nasal cavity, such as angioleiomyoma (AL) and angiomyolipoma (AML), are rare tumors that involve vascular, smooth muscle, and adipocytic components, with unclear classifications as hamartomas or true neoplasms due to limited genetic research.
  • A multi-institutional retrospective study collected data on 15 nasal cavity lesions, primarily affecting older males with obstructive symptoms, and analyzed tissue samples for genetic features.
  • The study discovered that most cases had a high proportion of smooth muscle, with some showing additional components like blood vessels and fatty tissue, while all lesions were positive for smooth muscle markers, indicating their muscular origin.
View Article and Find Full Text PDF

Purpose: Mesenchymal neoplasms composed of vascular, smooth muscle, and adipocytic components are uncommon in the nasal cavity. While angioleiomyoma (AL) is a smooth muscle tumor in the Head & Neck WHO classification, it is considered of pericytic origin in the Skin as well as Soft Tissue and Bone classifications. For nasal AL with an adipocytic component, the terms AL with adipocytic differentiation and angiomyolipoma (AML) have been applied, among others.

View Article and Find Full Text PDF

Clear cell renal cell carcinoma (CCRCC) and papillary renal cell carcinoma (PRCC) are the two most frequently encountered subtypes of renal cell carcinoma (RCC). Rarely, these two entities are identified intermingled within the same mass and have been labeled either collision tumors juxtaposed by random chance or composite tumors that have arisen from a common tumorigenic precursor cell. Regarding this distinction, authors have commonly relied upon macroscopic, histologic, and clinicopathologic findings, which may be prone to subjectivity.

View Article and Find Full Text PDF

Wastewaterbased epidemiology (WBE) can be used to monitor the community presence of infectious disease pathogens of public health concern such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Viral nucleic acid has been detected in the stool of SARS-CoV-2-infected individuals. Asymptomatic SARS-CoV-2 infections make community monitoring difficult without extensive and continuous population screening.

View Article and Find Full Text PDF

Background: Digital polymerase chain reaction (dPCR) is an accurate and sensitive molecular method that can be used in clinical diagnostic, prognostic, and predictive tests. The key component of the dPCR method is the partitioning of a single reaction into many thousands of droplets, nanochannels or other nano- or picoliter-sized reactions. This results in high enough sensitivity to detect rare nucleic acid targets and provides an absolute quantification of target sequences or alleles compared to other PCR-based methods.

View Article and Find Full Text PDF

The molecular pathogenesis of breast fibroepithelial tumors continues to be elucidated. Recently, highly recurrent mutations arising in exon 2 at codon 44 were discovered in fibroadenomas and phyllodes tumors. In addition, a high prevalence of promoter mutations in two hotspots (124 and 126 bp upstream from the translation start site) was discovered in up to 65% of phyllodes tumors.

View Article and Find Full Text PDF

Pathologic complete response (pCR) to neoadjuvant chemoradiation for locally advanced esophageal adenocarcinoma (EAC) confers significantly improved survival. The ability to infer pCR may spare esophagectomy in some patients. Currently, there are no validated biomarkers of pCR.

View Article and Find Full Text PDF

SARS-CoV-2 viral RNA is shed in the stool of 55-70% of infected individuals and can be detected in community wastewater up to 7 days before people present with COVID-19 symptoms. The detection of SARS-CoV-2 RNA in wastewater may serve as a lead indicator of increased community transmission. Here, we monitored viral concentrations in samples collected from nine municipal wastewater facilities in New Hampshire (NH) and Vermont (VT).

View Article and Find Full Text PDF

Dedifferentiated liposarcoma is a nonlipogenic sarcoma of variable histological grade that frequently arises in association with a well-differentiated liposarcoma. Dedifferentiation occurs in approximately 10% of well-differentiated liposarcomas and is most commonly encountered in the retroperitoneum. Dedifferentiated liposarcoma of the upper respiratory tract is an extremely rare occurrence.

View Article and Find Full Text PDF

The most recent World Health Organization classification for skin tumors (2018) categorizes melanomas and their precursor lesions, benign or intermediate, into nine pathways based not only on their clinical and histomorphologic characteristics but also on their molecular profile and genetic fingerprint. In an index case of a partially sampled atypical spitzoid lesion, which proved to be an 11p-amplified Spitz nevus with HRASQ61R mutation, we observed cross-reactivity with the NRASQ61R antibody (clone SP174). Overall, we assessed the status of HRAS and NRAS genes and their immunoreaction to NRASQ61R antibody in 16 cases of 11p-amplified Spitz nevi/atypical Spitz tumors.

View Article and Find Full Text PDF

As the landscape of melanomagenesis becomes better refined through increasingly detailed schema grounded in distinct clinicopathologic-molecular pathways, the stepwise process and variations of molecular nevogenesis have largely remained elusive. Herein, we present a series of 8 melanocytic nevi in patients ranging from 40 to 74 years of age (median: 59.5 y), which demonstrated a reproducible constellation of histomorphologic features as well as a copy number gain of the long arm of chromosome 15 (15q).

View Article and Find Full Text PDF

A small subset of cutaneous melanomas harbor oncogenic gene fusions, which could potentially serve as therapeutic targets for patients with advanced disease as novel therapies are developed. Fusions involving RAF1 are exceedingly rare in melanocytic neoplasms, occurring in less than 1% of melanomas, and usually arise in tumors that are wild type for BRAF, NRAS, and NF1. We describe herein a case of acral melanoma with two satellite metastases and sentinel lymph node involvement.

View Article and Find Full Text PDF

Background: Fluorescence in situ hybridization (FISH) and single nucleotide polymorphism (SNP) arrays are well-established molecular tests for the analysis of challenging melanocytic lesions. A 23-gene expression signature (GES), marketed as myPath Melanoma, is a recently introduced molecular test that categorizes melanocytic lesions as "benign," "malignant," and "indeterminate." There are few studies on the concordance between FISH, SNP, and GES in the analysis of melanocytic lesions.

View Article and Find Full Text PDF
Article Synopsis
  • Scientists studied gliomas, which are types of brain tumors, to see how changes in genes can affect how long patients live and how likely their cancer is to come back.
  • They looked at tissue samples from 293 patients to find specific gene mutations and other changes that might predict patient outcomes.
  • The findings showed that some gene mutations, like IDH1 and MGMT, were linked to better survival rates, while others, like FLT3 and TP53, were linked to worse outcomes.
View Article and Find Full Text PDF

The laboratory response to the current severe acute respiratory syndrome coronavirus 2 pandemic may be termed heroic. From the identification of the novel coronavirus to implementation of routine laboratory testing around the world to the development of potential vaccines, laboratories have played a critical role in the efforts to curtail this pandemic. In this brief report, we review our own effort at a midsized, rural, academic medical center to implement a molecular test for the virus; and we share insights and lessons learned from that process, which might be helpful in similar situations in the future.

View Article and Find Full Text PDF

The number of companies offering direct-to-consumer genetic tests is increasing. There is growing concern over whether direct-to-consumer genetic companies should be allowed to offer clinically relevant testing that has only been possible under medical care. Direct-to-consumer genetic testing can be incomplete, inaccurate, and inappropriate.

View Article and Find Full Text PDF

Undifferentiated melanoma should be considered in the differential diagnosis of sarcomatoid cutaneous malignancies to ensure that patients receive the correct treatment. Dermatopathologists should recognize the pitfalls of relying too heavily on immunohistochemistry to establish this diagnosis and consider ancillary tests, including single-nucleotide polymorphism (SNP) copy number arrays and targeted next-generation sequencing (NGS), when a definitive diagnosis cannot be rendered on a primary or metastatic tumor. This technology can also help to exclude a collision of melanoma and sarcoma when both differentiated and undifferentiated components are juxtaposed.

View Article and Find Full Text PDF

BRCA1-associated Protein 1 (BAP1)-inactivated melanocytic nevi/tumors (BIMT) have distinct morphologic features. A typical case exhibits a biphasic population of cytologically bland conventional melanocytes and a second proliferation of larger epithelioid melanocytes with abundant eosinophilic cytoplasm. The vast majority of cases harbor BRAF V600E in both components with bi-allelic inactivation of BAP1 in the epithelioid component by various molecular mechanisms resulting in loss of nuclear protein expression, which can be demonstrated by immunohistochemistry.

View Article and Find Full Text PDF

. The aim of this study was to identify potential driver genetic alterations in a dedifferentiated liposarcoma (DDLPS) with rhabdomyosarcomatous differentiation. .

View Article and Find Full Text PDF