Dr Varsha Deepu

❌ Myoepithelioma: • Composed exclusively of myoepithelial cells in a nested or trabecular arrangement. • Lacks the true ductal or tubular epithelial structures required for a mixed tumor. • Frequently associated with EWSR1 fusions, especially in the syncytial subtype.

❌ Syringoma: • Features small, well-circumscribed ducts with characteristic 'tadpole' tails. • Stroma is characteristically sclerotic and hyalinized rather than myxochondroid. • Typically arises in the upper dermis and lacks the large, deep nodular silhouette.

❌ Hidradenoma: • Displays a solid-cystic architecture dominated by clear or eosinophilic polygonal cells. • Lacks the prominent mesenchymal-like chondroid or osseous matrix. • Characterized by CRTC1::MAML2 fusions in up to 75% of cases.

✅ Mixed tumor 🎯🍹 • Biphasic sweat gland neoplasm with epithelial and mesenchymal elements. • Features branched tubules or round ducts set in a myxoid, chondroid, or osseous stroma. • Most apocrine-pattern cases harbor a diagnostic PLAG1 rearrangement. • Also known as chondroid syringoma, it is the cutaneous analog of pleomorphic adenoma.

#PathQuiz 🔬 #DermPath A) Mixed tumor B) Myoepithelioma C) Syringoma D) Hidradenoma #Pathology #DermPath

Not every epithelial tumor with papillary structures on the digit is an adenocarcinoma 🤔 Immunohistochemistry can help establish the diagnosis of hidradenoma with papillary structures. doi: 10.1097/DAD.0000000000002291 by @JCandidoXavier #ISDPDenver2026 #Path #pathology

What is the cause of Death and prevalence?

Synovial lipomatosis (lipoma arborescens, Hoffa's disease) ➡️Mature unremarkable fat extending to the partly hyperplastic synovial lining, imparting a villiform/papillary architecture ➡️Scattered chronic inflammation ➡️M>F, usually knee joint #BSTPath #PathTwitter #pathoutpic

❌ Atypical polypoid adenomyoma: • This lesion is distinguished by its stroma, which consists of benign smooth muscle rather than endometrial stroma. • It almost always shows squamous morular metaplasia, which is not the primary feature in this case. • It typically presents as a discrete clinical polyp in younger, reproductive-aged women.

❌ Endometrial polyp: • While polyps are localized, they are characterized by a specialized fibrous stroma and thick-walled vessels. • The glands within a polyp are typically inactive or show benign changes, not the complex architectural crowding seen here. • Polyp stroma often has a different appearance from the surrounding functional endometrium.

✅ Endometrial atypical hyperplasia / EIN 🎯 • Defined as a geographical lesion where the glandular volume exceeds the stromal volume. • Shows significant cytological atypia (loss of polarity, rounded nuclei) distinct from background glands. • It is a clonal proliferation and a direct precursor to low-grade endometrioid adenocarcinoma. • Often associated with loss of PTEN or PAX2 expression.

❌ Endometrial hyperplasia without atypia: • This represents a field effect of branched or dilated glands across the whole specimen. • Crucially, it lacks the localized, geographical expansion seen in atypical hyperplasia. • The nuclei remain Cigar-shaped and pseudostratified, lacking the rounded, pleomorphic look of EIN.

#PathQuiz 🔬 A) Hyperplasia without atypia B) Hyperplasia with atypia C) Endometrial polyp D) Atypical polypoid adenomyoma #Pathology #GYNPath #Endometrium Clue in caption 🧐

Case of The Week, Contributed by Dr. Michel Kmeid, Medical Director of gross room and frozen section. A 55-year-old presents with nodular mass in the temporomandibular joint with erosion of the glenoid fossa. Histologic sections from this lesion are shown below.

New in #HumPathol: Osteosarcomas with H3F3A mutation a clinicopathological and molecular genetic study of 7 cases with review of the literature. sciencedirect.com/science/articl… #pathology #PathTwitter #PathX #BSTpath

☝🏼papillary renal cell carcinoma (not shown) ✌🏼papillary adenoma (left), papillary neoplasm reverse polarity (right) #gupath #pathtwitter #pathoutpic

#twoforoneseries radical nephrectomy☝🏼well-circumscribed, variegated yellow-orange to red-brown, hemorrhagic mass ✌🏼incidental, irregular gray to yellow to slightly orange lesions (>15) throughout the kidney, ranging from minute to 0.8 cm in size

Florid Verumontanum mucosal gland hyperplasia of #prostate. Note glands with 2 cell layers, corpora amylacea, and distinctive orange-gray concretions. #GUPath

#GUpath prostate bx #beautyinb9: 😍typical glandular🔬& secretions from verumontanum

#slidearchiveseries biphasic hyalinizing psammomatous renal cell carcinoma #gupath #pathtwitter #pathoutpic 🔬 biphasic pattern: smaller cells around basement membrane material within larger acini, forming a glomeruloid pattern 🧬 assoc with somatic mutations in NF2 gene