Lipoblastoma-Related Volvulus in a Nine-Year-Old Female.

Lipoblastomas are benign neoplasms that arise from embryonal adipocytes. They predominantly impact the pediatric population, with most cases occurring in the first few years of life. These tumors typically present as a soft, palpable, painless mass and tend to involve the mesenchymal tissues of the extremities and trunk. Intraabdominal involvement and intraabdominal complications secondary to lipoblastoma are incredibly rare. Here, we present the case of a nine-year-old female who presented to the emergency department (ED) with one week of intermittent lower abdominal pain. The CT abdomen/pelvis demonstrated a well-circumscribed hypodense omental mass measuring 10.1 cm x 4.7 cm x 13.4 cm with minimal mass effect or bowel displacement. At that time, the patient's abdomen was soft without tenderness, distention, or rigidity. Her initial laboratory studies and vital signs were within normal limits. She was evaluated by pediatric surgery, who, given her clinical stability, planned for an anticipated elective resection. Thirteen days after her initial ED visit, the patient returned to the ED with nausea, vomiting, and diffuse abdominal pain. Repeat CT abdomen/pelvis revealed shifting of the omental mass from the left hemi-abdomen to the right hemi-abdomen with associated mesenteric 'swirl sign' and dilated loops of small bowel consistent with small bowel obstruction. Given the patient's CT findings and signs of peritonitis on a physical exam, she was emergently taken to the operating room, where the mass along with 20 cm of small bowel intimately associated with the mass was resected. The proximal end of the involved bowel was found to be twisted and necrotic, consistent with volvulus. A specimen was sent for cytogenetics and found to be positive for FLAG1, ultimately revealing a diagnosis of lipoblastoma. The majority of lipoblastoma development is underpinned by gene rearrangements in the zinc-finger transcription factor PLAG1. Although benign, these tumors can exhibit rapid proliferation and have high recurrence rates. Patients should be monitored long-term with ultrasound (US) or MRI following surgery to assess for recurrence.

Characterizing the Immature Immunophenotype of Sickle Cell Disease Monocytes.

Sickle cell disease (SCD) is marked by episodic vaso-occlusive crisis (VOC). Recurrent VOC creates a pro-inflammatory state that induces phenotypic alterations in innate immune cells. Monocytes are of particular interest to VOC pathophysiology because they are especially malleable to inflammatory signaling. Indeed, inflammatory disease states such as chronic obstructive pulmonary disease (COPD), obesity and atherosclerosis are known to influence monocyte development and alter monocyte subpopulations. In this study, we describe SCD monocyte subsets by performing immunophenotypic flow cytometric, enzymatic, and morphologic analysis on peripheral blood. Herein, we add to the growing body of evidence suggesting aberrant monocyte populations underpin VOC pathophysiology. We found that SCD monocytes possess an immature phenotype as demonstrated by 1) decreased CD4 positivity (p < .01), 2) low α-naphthyl butyrate esterase (ANBE) expression, and 3) naïve morphologic features. We additionally found an increase in CD14+CD16-CD4- monocytes (p < .01), a subset associated with the impaired immune response of post-trauma patients. Interestingly, we also found a large proportion of CD14+CD4-HLA-DR- monocytes which, under normal circumstances, are exclusively found in neonates (p < .01). Finally, we report an increase in nonclassical monocytes (CD14dimCD16+), a subset recently shown to have a critical role in prevention and recovery from VOC.

Placental and Breast Metastasis of Squamous Cell Carcinoma in a Patient With Recurrent Respiratory Papillomatosis.

Recurrent respiratory papillomatosis (RRP), which is usually benign, is an intractable disease characterized by recurrent papillomas (wart-like lesions). Although it most commonly involves the mucosal epithelial lining of the upper respiratory tract, on rare occasions, it can also involve lung parenchyma. RRP carries the risk of malignant transformation, most often to non-small-cell squamous lung cancer. Here, we present the case of a 32-year-old pregnant female with a past medical history of RRP who developed mild respiratory distress during her immediate postpartum period. This prompted imaging of the chest which revealed right lower lobe hypodensities with extensive hilar and perihilar lymphadenopathy. Histopathology of the bronchial specimen showed squamous cell carcinoma with 100% programmed death-ligand 1 (PD-L1) expression. Gross examination of the patient's placenta showed multiple tan-colored nodules which was confirmed on histopathological examination as multifocal regions of squamous cell carcinoma metastatic from the lung. The patient underwent a staging positron emission tomography (PET) scan which showed hypermetabolic regions in the right middle and lower lobes of the lung, with avidity in the right paratracheal region and an enhancing lesion in the left breast. Biopsy from the breast lesion was also positive for squamous cell carcinoma and PD-L1. She was diagnosed with Stage IVB (T1c, N3, M1c) non-small-cell squamous lung cancer and was started on pembrolizumab. Carboplatin and paclitaxel were added after an initial mixed response to therapy. The patient was non-compliant with her updated treatment regimen as well as with outpatient follow-up visits. A restaging PET scan demonstrated an inadequate response to the amended immunotherapy/chemotherapy regimen. Ultimately, she passed away within one and a half years of her initial diagnosis. Malignant transformation of papillomatous lesions into squamous cell cancer is infrequent, and the occurrence of metastasis to the breast and/or placenta is exceptionally rare. To our knowledge, this is the first reported case of placental and breast metastasis of squamous cell lung cancer in a patient with RRP.

A Protamine Knockdown Mimics the Function of Sd in Drosophila melanogaster.

Segregation Distorter (SD) is an autosomal meiotic drive system found worldwide in natural populations of Drosophila melanogaster This gene complex induces the preferential and nearly exclusive transmission of the SD chromosome in SD/SD+ males. This selfish propagation occurs through the interplay of the Sd locus, its enhancers and the Rsps locus during spermatid development. The key distorter locus, Sd, encodes a truncated but enzymatically active RanGAP (RanGTPase-activating protein), a key nuclear transport factor in the Ran signaling pathway. When encoded by Sd, RanGAP is mislocalized to the nucleus interior, which then traps Ran inside the nucleus and disrupts nuclear import. As a result of this aberrant nuclear transport, a process known as the histone-to-protamine transition that is required for proper spermatid condensation fails to occur in SD/SD+ males. In this process, sperm-specific protamine proteins enter the spermatid nucleus and replace the formerly chromatin-complexed histones. Previously, we have shown that mutations affecting nuclear import and export can enhance distortion in an SD background, thus verifying that a defect in nuclear transport is responsible for the unequal transmission of chromosomes. Herein, we show that specifically reducing protamines induces distortion in an SD background, verifying that protamines are transported via the RanGAP/GEF pathway and indicating that E(SD) plays a significant and unique role in the process of distortion.