Just a nice example of a benign entity in the breast, collagenous spherulosis Find this case on Twitter: Just a nice example of this benign entity in the breast. What’s your diagnosis? #BreastPath pic.twitter.com/nSNeXqoSxg — Clarissa E. Jordan, MD (@pathcejmd) October 26, 2022

This is an example of ✨ usual ductal hyperplasia (UDH) ✨, a benign intraductal proliferation. Key points: 📌 Associated with a 1.5 - 2 times increase in risk for subsequent breast cancer 📌 Progenitor epithelial cells (CK5+ in a moisaic to diffuse pattern) Other features labeled in the photo Thanks for following along

This image shows the collision of two entities 1️⃣ Pigmented seborrheic keratosis (L) 2️⃣ Squamous cell carcinoma in situ (R) Note: While there is definitely atypia on both sides of the image in the collision of these two entities, the left side better shows the features of an SK, while

Key histologic features: 📌 Superficial subcorneal acantholysis 📌 Prominent granular layer with possible dyskeratosis 📌 Predominantly lymphocytic infiltrate in the dermis DIF shows intercellular IgG and C3 predominantly w/in superficial epidermis That's all, thanks for following along! Find this case on Twitter: 👋🏼 Quick #DermPath case-based #tweetorial (yes, I’m finally

FISH (specifically D-FISH) provides rapid genetic confirmation of APL (🔬: multiple Auer rods) Benefits: * Rapid TAT * Ability to detect PML::RARA fusion gene even with cryptic 🤐 rearrangements (those that aren’t readily apparent on conventional karyotyping) This next case has numerous blasts w monoblastic morphology, and I’ll give away that

This is AML w/ t(6;9). Can be a/w basophilia, but not always (couldn’t find in this case) AML with t(6;9) is strongly associated with another genetic abnormality.... AML w/ t(6;9) is strongly associated with FLT3-ITD FLT3-ITD can also be a/w other

AML with biallelic CEBPA has a favorable prognosis Interestingly, only cases with biallelic CEBPA have a favorable prognosis! This is because AML with biallelic mutations have a different mutational landscape than AML with monoallelic mutations, which tends to have more cooperating mutations ⬇️ https://ashpublications.org/blood/article/124/21/2385/

Key features: Typically a triphasic (or more) neoplasm, though one pattern and cell type often predominates * Patterns: solid/lobular⬇️, microcystic, papillary, cystic⬇️, follicular * Cell types: serous acinar, intercalated duct cells, vacuolated cells, clear cells * Typical low to intermediate grade Clinical considerations: * Generally has a good prognosis w 5yr survival rate

AML (megakaryoblastic) with t(1;22) occurs in infants and young children less than 3 years old 1991 paper with more information: https://pubmed.ncbi.nlm.nih.gov/1859887/ The blasts in AML with t(1;22) have megakaryoblastic: * morphology, e.g cytoplasmic blebbing -- apologies, this case did not

Key features: * CMV-infected cells are 2-4x larger than normal * May contain Cowdry bodies (basophilic intranulcear inclusions surrounded by a clear halo) * May contain smaller intracytoplasmic inclusions Features in background colon (non-specific): * Architectural distortion * Cryptitis * Lymphoplasmacytic cellular infiltrates * Reactive atypia 🦠 CMV has high prevalence in the general population (50-80% have abs

Inversion of chromosome 16 is associated with acute myeloid leukemia with abnormal eosinophils These abnormal eosinophils have mixed eosinophilic and basophilic granules How is the cytogenetic abnormality determined diagnostically? A brief introduction to cytogenetics… Cytogenetics is the microscopic investigation of the DNA structure/content at the chromosomal level using banding

Platelet crossmatch is an effective screening test for antibody-mediated platelet refractoriness At first I didn’t understand the testing methods for platelet refractoriness, so I drew these cartoons during/after KreuterMD’s interactive teaching session yesterday and learned a lot in the process! The first test at that should be

A single, thin, tapered Auer rod is classic for AML with t(8;21) Other key points: There is an association with systemic mastocytosis in approximately 10% of cases RUNX1::RUNX1T1 is associated with the 8;21 translocation This fusion protein blocks transcription of genes involved in hematopoietic differentiation The

This is an example of MYH9-related disorder Historically, these disorders had distinct eponyms (e.g. May-Hegglin), but with much phenotypic and genotypic overlap, these are now classified as MYH9-related disorder. MYH9-related disorders are associated with large platelets (and thrombocytopenia) This one I found is large, but some platelets can even