Charlie Herndon

✅ Myofibroblastoma 🎯🧬 • Composed of short, stubby spindle cells arranged in fascicles with broad bands of hyalinized collagen. • Often features a variable adipocytic component and scattered mast cells. • Characterized by 13q14 deletions involving the RB1 locus, resulting in loss of nuclear RB1 expression. • This benign tumor is closely related to spindle cell lipoma and cellular angiofibroma in its pathogenetic mechanism.

❌ Spindle Cell Lipoma: • Contains a triad of mature fat, bland spindle cells, and characteristically 'ropy' collagen bundles. • Myxoid matrix and mast cells are frequent, but it lacks the broad, hyalinized collagen bands of myofibroblastoma. • Belongs to the same 13q-deleted family but displays a different stromal collagen pattern.

#PathQuiz 🔬🧬 #SoftTissuePath A) Solitary Fibrous Tumor B) Cellular Angiofibroma C) Spindle Cell Lipoma D) Myofibroblastoma

✅ Prostatic Ductal Adenocarcinoma 🎯🧬 • Composed of tall pseudostratified columnar cells forming papillary or complex cribriform glands • Papillae characteristically contain fibrovascular cores and cells show elongated high-grade nuclei • Frequently harbors mutations in the WNT signaling pathway, including activating CTNNB1 or inactivating APC mutations • This aggressive subtype carries a higher risk of biochemical failure and unusual visceral metastases compared to acinar carcinoma

❌ Conventional Acinar Adenocarcinoma: • Typically composed of small, discrete glands lined by a single layer of cuboidal cells • Lacks the characteristic tall columnar epithelium and papillary fronds of the ductal subtype • While it shares ERG rearrangements, mutations in the WNT signaling pathway are significantly less common

#PathQuiz 🔬 A) High-grade prostatic intraepithelial neoplasia B) Intraductal Carcinoma of the Prostate C) Conventional Acinar Adenocarcinoma D) Prostatic Ductal Adenocarcinoma #Pathology #GUPath 🧬 #ProstatePath

✅ Lipoblastoma 🎯👶 • Benign embryonal white fat tumor demonstrating a distinct lobular architecture with myxoid matrix and variable lipoblasts. • Shows a spectrum of maturation often progressing toward mature fat at the center of lobules. • Characterized by PLAG1 gene rearrangements, often resulting from structural alterations of chromosome 8q11-q13. • Excellent prognosis after complete excision, though recurrence may occur if incompletely removed.

❌ Myxoid Liposarcoma: • Composed of uniform round-to-ovoid cells and small lipoblasts with a characteristic chicken-wire vascular pattern. • Exceptionally rare in infants and toddlers, typically occurring in adults, and lacks the overall lobular maturation seen here. • Defined by a FUS::DDIT3 or EWSR1::DDIT3 gene fusion.

#PathQuiz 🔬👶 #SoftTissuePath A) Lipoma B) Fibrous Hamartoma of Infancy C) Myxoid Liposarcoma D) Lipoblastoma #Pathology #SoftTissuePath #PediatricPath