Metastatic Malignant Peripheral Nerve Sheath Tumor (MPNST) in Neurofibromatosis Type 1: Challenges in Diagnosis and Management.

Malignant peripheral nerve sheath tumors (MPNSTs) are growths that arise in conjunction with a peripheral nerve and are believed to originate from neural crest cells. These tumors can arise sporadically but are often associated with the cancer-predisposing genetic condition, neurofibromatosis type 1 (NF-1). The clinical presentation of an enlarging mass, pain, paresthesias, and neurologic deficits can mirror that of other soft tissue sarcomas.

Human Intestinal Spirochetosis: A Rare Case of Intermittent Bloating and Hematochezia.

Human intestinal spirochetosis (HIS) is a condition where spirochetes, a group of spiral-shaped bacteria, attach to the apical membrane of the human colorectal epithelium. Although most findings of HIS are simply incidental discoveries found during screening colonoscopies, the ability to mimic the presentation of inflammatory bowel diseases should prompt consideration of this condition as part of a working differential diagnosis. Herein, we present the case of a 57-year-old bisexual, African American male with a medical history of Human Immunodeficiency Virus (HIV) on antiretroviral therapy (ART) with an undetectable viral load that presented for an elective, outpatient colonoscopy after experiencing four months of intermittent bloating and hematochezia.

Monitoring of Dynamic Changes and Clonal Evolution in Circulating Tumor DNA From Patients With -Mutated Cholangiocarcinoma Treated With Isocitrate Dehydrogenase Inhibitors.

Purpose: mutations occur in about 30% of patients with cholangiocarcinoma. Analysis of mutations in circulating tumor DNA (ctDNA) can be performed by droplet digital polymerase chain reaction (ddPCR). The analysis of ctDNA is a feasible approach to detect mutations.

PIK3CA mutations in plasma circulating tumor DNA predict survival and treatment outcomes in patients with advanced cancers.

Background: Oncogenic mutations in PIK3CA are prevalent in diverse cancers and can be targeted with inhibitors of the phosphoinositide-3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) pathway. Analysis of circulating tumor DNA (ctDNA) provides a minimally invasive approach to detect clinically actionable PIK3CA mutations.

Patients And Methods: We analyzed PIK3CA hotspot mutation frequency by droplet digital PCR (QX 200; BioRad) using 16 ng of unamplified plasma-derived cell-free DNA from 68 patients with advanced solid tumors (breast cancer, n = 41; colorectal cancer, n = 13; other tumor types, n = 14).

Accurate Quantification of Monoclonal Immunoglobulins Migrating in the Beta Region on Protein Electrophoresis.

Background: The concentration of monoclonal immunoglobulins (Igs) in neoplastic monoclonal gammopathic manifestations is generally measured by densitometric scanning of the monoclonal peaks on gel or by measuring absorbance at 210 nm in capillary electrophoresis (CE). For monoclonal Igs migrating in the beta region, measurement is complicated by the major beta-region proteins, namely, transferrin and C3.

Methods: C3 interference in densitometry was eliminated by heat treatment of serum, and monoclonal Igs were quantified by densitometry of the residual band.